e11e3f187d
be careful not to fix anything that was already broken; the NFSv4 code is particularly bad in this respect.
4629 lines
107 KiB
C
4629 lines
107 KiB
C
/*-
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* Copyright (c) 2003-2008 Joseph Koshy
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* Copyright (c) 2007 The FreeBSD Foundation
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* All rights reserved.
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*
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* Portions of this software were developed by A. Joseph Koshy under
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* sponsorship from the FreeBSD Foundation and Google, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/eventhandler.h>
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#include <sys/jail.h>
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#include <sys/kernel.h>
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#include <sys/kthread.h>
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#include <sys/limits.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#include <sys/module.h>
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#include <sys/mutex.h>
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#include <sys/pmc.h>
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#include <sys/pmckern.h>
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#include <sys/pmclog.h>
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#include <sys/priv.h>
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#include <sys/proc.h>
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#include <sys/queue.h>
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#include <sys/resourcevar.h>
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#include <sys/sched.h>
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#include <sys/signalvar.h>
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#include <sys/smp.h>
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#include <sys/sx.h>
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#include <sys/sysctl.h>
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#include <sys/sysent.h>
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#include <sys/systm.h>
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#include <sys/vnode.h>
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#include <sys/linker.h> /* needs to be after <sys/malloc.h> */
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#include <machine/atomic.h>
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#include <machine/md_var.h>
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|
|
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/*
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* Types
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*/
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enum pmc_flags {
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PMC_FLAG_NONE = 0x00, /* do nothing */
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PMC_FLAG_REMOVE = 0x01, /* atomically remove entry from hash */
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PMC_FLAG_ALLOCATE = 0x02, /* add entry to hash if not found */
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};
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/*
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* The offset in sysent where the syscall is allocated.
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*/
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static int pmc_syscall_num = NO_SYSCALL;
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struct pmc_cpu **pmc_pcpu; /* per-cpu state */
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pmc_value_t *pmc_pcpu_saved; /* saved PMC values: CSW handling */
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#define PMC_PCPU_SAVED(C,R) pmc_pcpu_saved[(R) + md->pmd_npmc*(C)]
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struct mtx_pool *pmc_mtxpool;
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static int *pmc_pmcdisp; /* PMC row dispositions */
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#define PMC_ROW_DISP_IS_FREE(R) (pmc_pmcdisp[(R)] == 0)
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#define PMC_ROW_DISP_IS_THREAD(R) (pmc_pmcdisp[(R)] > 0)
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#define PMC_ROW_DISP_IS_STANDALONE(R) (pmc_pmcdisp[(R)] < 0)
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#define PMC_MARK_ROW_FREE(R) do { \
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pmc_pmcdisp[(R)] = 0; \
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} while (0)
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#define PMC_MARK_ROW_STANDALONE(R) do { \
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KASSERT(pmc_pmcdisp[(R)] <= 0, ("[pmc,%d] row disposition error", \
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__LINE__)); \
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atomic_add_int(&pmc_pmcdisp[(R)], -1); \
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KASSERT(pmc_pmcdisp[(R)] >= (-pmc_cpu_max_active()), \
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("[pmc,%d] row disposition error", __LINE__)); \
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} while (0)
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#define PMC_UNMARK_ROW_STANDALONE(R) do { \
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atomic_add_int(&pmc_pmcdisp[(R)], 1); \
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KASSERT(pmc_pmcdisp[(R)] <= 0, ("[pmc,%d] row disposition error", \
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__LINE__)); \
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} while (0)
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#define PMC_MARK_ROW_THREAD(R) do { \
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KASSERT(pmc_pmcdisp[(R)] >= 0, ("[pmc,%d] row disposition error", \
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__LINE__)); \
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atomic_add_int(&pmc_pmcdisp[(R)], 1); \
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} while (0)
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#define PMC_UNMARK_ROW_THREAD(R) do { \
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atomic_add_int(&pmc_pmcdisp[(R)], -1); \
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KASSERT(pmc_pmcdisp[(R)] >= 0, ("[pmc,%d] row disposition error", \
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__LINE__)); \
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} while (0)
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|
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/* various event handlers */
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static eventhandler_tag pmc_exit_tag, pmc_fork_tag;
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/* Module statistics */
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struct pmc_op_getdriverstats pmc_stats;
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/* Machine/processor dependent operations */
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struct pmc_mdep *md;
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/*
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* Hash tables mapping owner processes and target threads to PMCs.
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*/
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struct mtx pmc_processhash_mtx; /* spin mutex */
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static u_long pmc_processhashmask;
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static LIST_HEAD(pmc_processhash, pmc_process) *pmc_processhash;
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/*
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* Hash table of PMC owner descriptors. This table is protected by
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* the shared PMC "sx" lock.
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*/
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static u_long pmc_ownerhashmask;
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static LIST_HEAD(pmc_ownerhash, pmc_owner) *pmc_ownerhash;
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/*
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* List of PMC owners with system-wide sampling PMCs.
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*/
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static LIST_HEAD(, pmc_owner) pmc_ss_owners;
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/*
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* Prototypes
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*/
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#ifdef DEBUG
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static int pmc_debugflags_sysctl_handler(SYSCTL_HANDLER_ARGS);
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static int pmc_debugflags_parse(char *newstr, char *fence);
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#endif
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static int load(struct module *module, int cmd, void *arg);
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static int pmc_attach_process(struct proc *p, struct pmc *pm);
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static struct pmc *pmc_allocate_pmc_descriptor(void);
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static struct pmc_owner *pmc_allocate_owner_descriptor(struct proc *p);
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static int pmc_attach_one_process(struct proc *p, struct pmc *pm);
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static int pmc_can_allocate_rowindex(struct proc *p, unsigned int ri,
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int cpu);
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static int pmc_can_attach(struct pmc *pm, struct proc *p);
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static void pmc_capture_user_callchain(int cpu, struct trapframe *tf);
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static void pmc_cleanup(void);
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static int pmc_detach_process(struct proc *p, struct pmc *pm);
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static int pmc_detach_one_process(struct proc *p, struct pmc *pm,
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int flags);
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static void pmc_destroy_owner_descriptor(struct pmc_owner *po);
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static struct pmc_owner *pmc_find_owner_descriptor(struct proc *p);
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static int pmc_find_pmc(pmc_id_t pmcid, struct pmc **pm);
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static struct pmc *pmc_find_pmc_descriptor_in_process(struct pmc_owner *po,
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pmc_id_t pmc);
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static struct pmc_process *pmc_find_process_descriptor(struct proc *p,
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uint32_t mode);
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static void pmc_force_context_switch(void);
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static void pmc_link_target_process(struct pmc *pm,
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struct pmc_process *pp);
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static void pmc_log_all_process_mappings(struct pmc_owner *po);
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static void pmc_log_kernel_mappings(struct pmc *pm);
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static void pmc_log_process_mappings(struct pmc_owner *po, struct proc *p);
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static void pmc_maybe_remove_owner(struct pmc_owner *po);
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static void pmc_process_csw_in(struct thread *td);
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static void pmc_process_csw_out(struct thread *td);
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static void pmc_process_exit(void *arg, struct proc *p);
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static void pmc_process_fork(void *arg, struct proc *p1,
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struct proc *p2, int n);
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static void pmc_process_samples(int cpu);
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static void pmc_release_pmc_descriptor(struct pmc *pmc);
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static void pmc_remove_owner(struct pmc_owner *po);
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static void pmc_remove_process_descriptor(struct pmc_process *pp);
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static void pmc_restore_cpu_binding(struct pmc_binding *pb);
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static void pmc_save_cpu_binding(struct pmc_binding *pb);
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static void pmc_select_cpu(int cpu);
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static int pmc_start(struct pmc *pm);
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static int pmc_stop(struct pmc *pm);
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static int pmc_syscall_handler(struct thread *td, void *syscall_args);
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static void pmc_unlink_target_process(struct pmc *pmc,
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struct pmc_process *pp);
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/*
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* Kernel tunables and sysctl(8) interface.
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*/
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SYSCTL_NODE(_kern, OID_AUTO, hwpmc, CTLFLAG_RW, 0, "HWPMC parameters");
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static int pmc_callchaindepth = PMC_CALLCHAIN_DEPTH;
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TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "callchaindepth", &pmc_callchaindepth);
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SYSCTL_INT(_kern_hwpmc, OID_AUTO, callchaindepth, CTLFLAG_TUN|CTLFLAG_RD,
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&pmc_callchaindepth, 0, "depth of call chain records");
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#ifdef DEBUG
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struct pmc_debugflags pmc_debugflags = PMC_DEBUG_DEFAULT_FLAGS;
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char pmc_debugstr[PMC_DEBUG_STRSIZE];
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TUNABLE_STR(PMC_SYSCTL_NAME_PREFIX "debugflags", pmc_debugstr,
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sizeof(pmc_debugstr));
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SYSCTL_PROC(_kern_hwpmc, OID_AUTO, debugflags,
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CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_TUN,
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0, 0, pmc_debugflags_sysctl_handler, "A", "debug flags");
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#endif
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/*
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* kern.hwpmc.hashrows -- determines the number of rows in the
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* of the hash table used to look up threads
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*/
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static int pmc_hashsize = PMC_HASH_SIZE;
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TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "hashsize", &pmc_hashsize);
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SYSCTL_INT(_kern_hwpmc, OID_AUTO, hashsize, CTLFLAG_TUN|CTLFLAG_RD,
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&pmc_hashsize, 0, "rows in hash tables");
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/*
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* kern.hwpmc.nsamples --- number of PC samples/callchain stacks per CPU
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*/
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static int pmc_nsamples = PMC_NSAMPLES;
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TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "nsamples", &pmc_nsamples);
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SYSCTL_INT(_kern_hwpmc, OID_AUTO, nsamples, CTLFLAG_TUN|CTLFLAG_RD,
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&pmc_nsamples, 0, "number of PC samples per CPU");
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|
|
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/*
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* kern.hwpmc.mtxpoolsize -- number of mutexes in the mutex pool.
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*/
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static int pmc_mtxpool_size = PMC_MTXPOOL_SIZE;
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TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "mtxpoolsize", &pmc_mtxpool_size);
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SYSCTL_INT(_kern_hwpmc, OID_AUTO, mtxpoolsize, CTLFLAG_TUN|CTLFLAG_RD,
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&pmc_mtxpool_size, 0, "size of spin mutex pool");
|
|
|
|
|
|
/*
|
|
* security.bsd.unprivileged_syspmcs -- allow non-root processes to
|
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* allocate system-wide PMCs.
|
|
*
|
|
* Allowing unprivileged processes to allocate system PMCs is convenient
|
|
* if system-wide measurements need to be taken concurrently with other
|
|
* per-process measurements. This feature is turned off by default.
|
|
*/
|
|
|
|
static int pmc_unprivileged_syspmcs = 0;
|
|
TUNABLE_INT("security.bsd.unprivileged_syspmcs", &pmc_unprivileged_syspmcs);
|
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SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_syspmcs, CTLFLAG_RW,
|
|
&pmc_unprivileged_syspmcs, 0,
|
|
"allow unprivileged process to allocate system PMCs");
|
|
|
|
/*
|
|
* Hash function. Discard the lower 2 bits of the pointer since
|
|
* these are always zero for our uses. The hash multiplier is
|
|
* round((2^LONG_BIT) * ((sqrt(5)-1)/2)).
|
|
*/
|
|
|
|
#if LONG_BIT == 64
|
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#define _PMC_HM 11400714819323198486u
|
|
#elif LONG_BIT == 32
|
|
#define _PMC_HM 2654435769u
|
|
#else
|
|
#error Must know the size of 'long' to compile
|
|
#endif
|
|
|
|
#define PMC_HASH_PTR(P,M) ((((unsigned long) (P) >> 2) * _PMC_HM) & (M))
|
|
|
|
/*
|
|
* Syscall structures
|
|
*/
|
|
|
|
/* The `sysent' for the new syscall */
|
|
static struct sysent pmc_sysent = {
|
|
2, /* sy_narg */
|
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pmc_syscall_handler /* sy_call */
|
|
};
|
|
|
|
static struct syscall_module_data pmc_syscall_mod = {
|
|
load,
|
|
NULL,
|
|
&pmc_syscall_num,
|
|
&pmc_sysent,
|
|
{ 0, NULL }
|
|
};
|
|
|
|
static moduledata_t pmc_mod = {
|
|
PMC_MODULE_NAME,
|
|
syscall_module_handler,
|
|
&pmc_syscall_mod
|
|
};
|
|
|
|
DECLARE_MODULE(pmc, pmc_mod, SI_SUB_SMP, SI_ORDER_ANY);
|
|
MODULE_VERSION(pmc, PMC_VERSION);
|
|
|
|
#ifdef DEBUG
|
|
enum pmc_dbgparse_state {
|
|
PMCDS_WS, /* in whitespace */
|
|
PMCDS_MAJOR, /* seen a major keyword */
|
|
PMCDS_MINOR
|
|
};
|
|
|
|
static int
|
|
pmc_debugflags_parse(char *newstr, char *fence)
|
|
{
|
|
char c, *p, *q;
|
|
struct pmc_debugflags *tmpflags;
|
|
int error, found, *newbits, tmp;
|
|
size_t kwlen;
|
|
|
|
tmpflags = malloc(sizeof(*tmpflags), M_PMC, M_WAITOK|M_ZERO);
|
|
|
|
p = newstr;
|
|
error = 0;
|
|
|
|
for (; p < fence && (c = *p); p++) {
|
|
|
|
/* skip white space */
|
|
if (c == ' ' || c == '\t')
|
|
continue;
|
|
|
|
/* look for a keyword followed by "=" */
|
|
for (q = p; p < fence && (c = *p) && c != '='; p++)
|
|
;
|
|
if (c != '=') {
|
|
error = EINVAL;
|
|
goto done;
|
|
}
|
|
|
|
kwlen = p - q;
|
|
newbits = NULL;
|
|
|
|
/* lookup flag group name */
|
|
#define DBG_SET_FLAG_MAJ(S,F) \
|
|
if (kwlen == sizeof(S)-1 && strncmp(q, S, kwlen) == 0) \
|
|
newbits = &tmpflags->pdb_ ## F;
|
|
|
|
DBG_SET_FLAG_MAJ("cpu", CPU);
|
|
DBG_SET_FLAG_MAJ("csw", CSW);
|
|
DBG_SET_FLAG_MAJ("logging", LOG);
|
|
DBG_SET_FLAG_MAJ("module", MOD);
|
|
DBG_SET_FLAG_MAJ("md", MDP);
|
|
DBG_SET_FLAG_MAJ("owner", OWN);
|
|
DBG_SET_FLAG_MAJ("pmc", PMC);
|
|
DBG_SET_FLAG_MAJ("process", PRC);
|
|
DBG_SET_FLAG_MAJ("sampling", SAM);
|
|
|
|
if (newbits == NULL) {
|
|
error = EINVAL;
|
|
goto done;
|
|
}
|
|
|
|
p++; /* skip the '=' */
|
|
|
|
/* Now parse the individual flags */
|
|
tmp = 0;
|
|
newflag:
|
|
for (q = p; p < fence && (c = *p); p++)
|
|
if (c == ' ' || c == '\t' || c == ',')
|
|
break;
|
|
|
|
/* p == fence or c == ws or c == "," or c == 0 */
|
|
|
|
if ((kwlen = p - q) == 0) {
|
|
*newbits = tmp;
|
|
continue;
|
|
}
|
|
|
|
found = 0;
|
|
#define DBG_SET_FLAG_MIN(S,F) \
|
|
if (kwlen == sizeof(S)-1 && strncmp(q, S, kwlen) == 0) \
|
|
tmp |= found = (1 << PMC_DEBUG_MIN_ ## F)
|
|
|
|
/* a '*' denotes all possible flags in the group */
|
|
if (kwlen == 1 && *q == '*')
|
|
tmp = found = ~0;
|
|
/* look for individual flag names */
|
|
DBG_SET_FLAG_MIN("allocaterow", ALR);
|
|
DBG_SET_FLAG_MIN("allocate", ALL);
|
|
DBG_SET_FLAG_MIN("attach", ATT);
|
|
DBG_SET_FLAG_MIN("bind", BND);
|
|
DBG_SET_FLAG_MIN("config", CFG);
|
|
DBG_SET_FLAG_MIN("exec", EXC);
|
|
DBG_SET_FLAG_MIN("exit", EXT);
|
|
DBG_SET_FLAG_MIN("find", FND);
|
|
DBG_SET_FLAG_MIN("flush", FLS);
|
|
DBG_SET_FLAG_MIN("fork", FRK);
|
|
DBG_SET_FLAG_MIN("getbuf", GTB);
|
|
DBG_SET_FLAG_MIN("hook", PMH);
|
|
DBG_SET_FLAG_MIN("init", INI);
|
|
DBG_SET_FLAG_MIN("intr", INT);
|
|
DBG_SET_FLAG_MIN("linktarget", TLK);
|
|
DBG_SET_FLAG_MIN("mayberemove", OMR);
|
|
DBG_SET_FLAG_MIN("ops", OPS);
|
|
DBG_SET_FLAG_MIN("read", REA);
|
|
DBG_SET_FLAG_MIN("register", REG);
|
|
DBG_SET_FLAG_MIN("release", REL);
|
|
DBG_SET_FLAG_MIN("remove", ORM);
|
|
DBG_SET_FLAG_MIN("sample", SAM);
|
|
DBG_SET_FLAG_MIN("scheduleio", SIO);
|
|
DBG_SET_FLAG_MIN("select", SEL);
|
|
DBG_SET_FLAG_MIN("signal", SIG);
|
|
DBG_SET_FLAG_MIN("swi", SWI);
|
|
DBG_SET_FLAG_MIN("swo", SWO);
|
|
DBG_SET_FLAG_MIN("start", STA);
|
|
DBG_SET_FLAG_MIN("stop", STO);
|
|
DBG_SET_FLAG_MIN("syscall", PMS);
|
|
DBG_SET_FLAG_MIN("unlinktarget", TUL);
|
|
DBG_SET_FLAG_MIN("write", WRI);
|
|
if (found == 0) {
|
|
/* unrecognized flag name */
|
|
error = EINVAL;
|
|
goto done;
|
|
}
|
|
|
|
if (c == 0 || c == ' ' || c == '\t') { /* end of flag group */
|
|
*newbits = tmp;
|
|
continue;
|
|
}
|
|
|
|
p++;
|
|
goto newflag;
|
|
}
|
|
|
|
/* save the new flag set */
|
|
bcopy(tmpflags, &pmc_debugflags, sizeof(pmc_debugflags));
|
|
|
|
done:
|
|
free(tmpflags, M_PMC);
|
|
return error;
|
|
}
|
|
|
|
static int
|
|
pmc_debugflags_sysctl_handler(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
char *fence, *newstr;
|
|
int error;
|
|
unsigned int n;
|
|
|
|
(void) arg1; (void) arg2; /* unused parameters */
|
|
|
|
n = sizeof(pmc_debugstr);
|
|
newstr = malloc(n, M_PMC, M_ZERO|M_WAITOK);
|
|
(void) strlcpy(newstr, pmc_debugstr, n);
|
|
|
|
error = sysctl_handle_string(oidp, newstr, n, req);
|
|
|
|
/* if there is a new string, parse and copy it */
|
|
if (error == 0 && req->newptr != NULL) {
|
|
fence = newstr + (n < req->newlen ? n : req->newlen + 1);
|
|
if ((error = pmc_debugflags_parse(newstr, fence)) == 0)
|
|
(void) strlcpy(pmc_debugstr, newstr,
|
|
sizeof(pmc_debugstr));
|
|
}
|
|
|
|
free(newstr, M_PMC);
|
|
|
|
return error;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Concurrency Control
|
|
*
|
|
* The driver manages the following data structures:
|
|
*
|
|
* - target process descriptors, one per target process
|
|
* - owner process descriptors (and attached lists), one per owner process
|
|
* - lookup hash tables for owner and target processes
|
|
* - PMC descriptors (and attached lists)
|
|
* - per-cpu hardware state
|
|
* - the 'hook' variable through which the kernel calls into
|
|
* this module
|
|
* - the machine hardware state (managed by the MD layer)
|
|
*
|
|
* These data structures are accessed from:
|
|
*
|
|
* - thread context-switch code
|
|
* - interrupt handlers (possibly on multiple cpus)
|
|
* - kernel threads on multiple cpus running on behalf of user
|
|
* processes doing system calls
|
|
* - this driver's private kernel threads
|
|
*
|
|
* = Locks and Locking strategy =
|
|
*
|
|
* The driver uses four locking strategies for its operation:
|
|
*
|
|
* - The global SX lock "pmc_sx" is used to protect internal
|
|
* data structures.
|
|
*
|
|
* Calls into the module by syscall() start with this lock being
|
|
* held in exclusive mode. Depending on the requested operation,
|
|
* the lock may be downgraded to 'shared' mode to allow more
|
|
* concurrent readers into the module. Calls into the module from
|
|
* other parts of the kernel acquire the lock in shared mode.
|
|
*
|
|
* This SX lock is held in exclusive mode for any operations that
|
|
* modify the linkages between the driver's internal data structures.
|
|
*
|
|
* The 'pmc_hook' function pointer is also protected by this lock.
|
|
* It is only examined with the sx lock held in exclusive mode. The
|
|
* kernel module is allowed to be unloaded only with the sx lock held
|
|
* in exclusive mode. In normal syscall handling, after acquiring the
|
|
* pmc_sx lock we first check that 'pmc_hook' is non-null before
|
|
* proceeding. This prevents races between the thread unloading the module
|
|
* and other threads seeking to use the module.
|
|
*
|
|
* - Lookups of target process structures and owner process structures
|
|
* cannot use the global "pmc_sx" SX lock because these lookups need
|
|
* to happen during context switches and in other critical sections
|
|
* where sleeping is not allowed. We protect these lookup tables
|
|
* with their own private spin-mutexes, "pmc_processhash_mtx" and
|
|
* "pmc_ownerhash_mtx".
|
|
*
|
|
* - Interrupt handlers work in a lock free manner. At interrupt
|
|
* time, handlers look at the PMC pointer (phw->phw_pmc) configured
|
|
* when the PMC was started. If this pointer is NULL, the interrupt
|
|
* is ignored after updating driver statistics. We ensure that this
|
|
* pointer is set (using an atomic operation if necessary) before the
|
|
* PMC hardware is started. Conversely, this pointer is unset atomically
|
|
* only after the PMC hardware is stopped.
|
|
*
|
|
* We ensure that everything needed for the operation of an
|
|
* interrupt handler is available without it needing to acquire any
|
|
* locks. We also ensure that a PMC's software state is destroyed only
|
|
* after the PMC is taken off hardware (on all CPUs).
|
|
*
|
|
* - Context-switch handling with process-private PMCs needs more
|
|
* care.
|
|
*
|
|
* A given process may be the target of multiple PMCs. For example,
|
|
* PMCATTACH and PMCDETACH may be requested by a process on one CPU
|
|
* while the target process is running on another. A PMC could also
|
|
* be getting released because its owner is exiting. We tackle
|
|
* these situations in the following manner:
|
|
*
|
|
* - each target process structure 'pmc_process' has an array
|
|
* of 'struct pmc *' pointers, one for each hardware PMC.
|
|
*
|
|
* - At context switch IN time, each "target" PMC in RUNNING state
|
|
* gets started on hardware and a pointer to each PMC is copied into
|
|
* the per-cpu phw array. The 'runcount' for the PMC is
|
|
* incremented.
|
|
*
|
|
* - At context switch OUT time, all process-virtual PMCs are stopped
|
|
* on hardware. The saved value is added to the PMCs value field
|
|
* only if the PMC is in a non-deleted state (the PMCs state could
|
|
* have changed during the current time slice).
|
|
*
|
|
* Note that since in-between a switch IN on a processor and a switch
|
|
* OUT, the PMC could have been released on another CPU. Therefore
|
|
* context switch OUT always looks at the hardware state to turn
|
|
* OFF PMCs and will update a PMC's saved value only if reachable
|
|
* from the target process record.
|
|
*
|
|
* - OP PMCRELEASE could be called on a PMC at any time (the PMC could
|
|
* be attached to many processes at the time of the call and could
|
|
* be active on multiple CPUs).
|
|
*
|
|
* We prevent further scheduling of the PMC by marking it as in
|
|
* state 'DELETED'. If the runcount of the PMC is non-zero then
|
|
* this PMC is currently running on a CPU somewhere. The thread
|
|
* doing the PMCRELEASE operation waits by repeatedly doing a
|
|
* pause() till the runcount comes to zero.
|
|
*
|
|
* The contents of a PMC descriptor (struct pmc) are protected using
|
|
* a spin-mutex. In order to save space, we use a mutex pool.
|
|
*
|
|
* In terms of lock types used by witness(4), we use:
|
|
* - Type "pmc-sx", used by the global SX lock.
|
|
* - Type "pmc-sleep", for sleep mutexes used by logger threads.
|
|
* - Type "pmc-per-proc", for protecting PMC owner descriptors.
|
|
* - Type "pmc-leaf", used for all other spin mutexes.
|
|
*/
|
|
|
|
/*
|
|
* save the cpu binding of the current kthread
|
|
*/
|
|
|
|
static void
|
|
pmc_save_cpu_binding(struct pmc_binding *pb)
|
|
{
|
|
PMCDBG(CPU,BND,2, "%s", "save-cpu");
|
|
thread_lock(curthread);
|
|
pb->pb_bound = sched_is_bound(curthread);
|
|
pb->pb_cpu = curthread->td_oncpu;
|
|
thread_unlock(curthread);
|
|
PMCDBG(CPU,BND,2, "save-cpu cpu=%d", pb->pb_cpu);
|
|
}
|
|
|
|
/*
|
|
* restore the cpu binding of the current thread
|
|
*/
|
|
|
|
static void
|
|
pmc_restore_cpu_binding(struct pmc_binding *pb)
|
|
{
|
|
PMCDBG(CPU,BND,2, "restore-cpu curcpu=%d restore=%d",
|
|
curthread->td_oncpu, pb->pb_cpu);
|
|
thread_lock(curthread);
|
|
if (pb->pb_bound)
|
|
sched_bind(curthread, pb->pb_cpu);
|
|
else
|
|
sched_unbind(curthread);
|
|
thread_unlock(curthread);
|
|
PMCDBG(CPU,BND,2, "%s", "restore-cpu done");
|
|
}
|
|
|
|
/*
|
|
* move execution over the specified cpu and bind it there.
|
|
*/
|
|
|
|
static void
|
|
pmc_select_cpu(int cpu)
|
|
{
|
|
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
|
|
("[pmc,%d] bad cpu number %d", __LINE__, cpu));
|
|
|
|
/* Never move to an inactive CPU. */
|
|
KASSERT(pmc_cpu_is_active(cpu), ("[pmc,%d] selecting inactive "
|
|
"CPU %d", __LINE__, cpu));
|
|
|
|
PMCDBG(CPU,SEL,2, "select-cpu cpu=%d", cpu);
|
|
thread_lock(curthread);
|
|
sched_bind(curthread, cpu);
|
|
thread_unlock(curthread);
|
|
|
|
KASSERT(curthread->td_oncpu == cpu,
|
|
("[pmc,%d] CPU not bound [cpu=%d, curr=%d]", __LINE__,
|
|
cpu, curthread->td_oncpu));
|
|
|
|
PMCDBG(CPU,SEL,2, "select-cpu cpu=%d ok", cpu);
|
|
}
|
|
|
|
/*
|
|
* Force a context switch.
|
|
*
|
|
* We do this by pause'ing for 1 tick -- invoking mi_switch() is not
|
|
* guaranteed to force a context switch.
|
|
*/
|
|
|
|
static void
|
|
pmc_force_context_switch(void)
|
|
{
|
|
|
|
pause("pmcctx", 1);
|
|
}
|
|
|
|
/*
|
|
* Get the file name for an executable. This is a simple wrapper
|
|
* around vn_fullpath(9).
|
|
*/
|
|
|
|
static void
|
|
pmc_getfilename(struct vnode *v, char **fullpath, char **freepath)
|
|
{
|
|
|
|
*fullpath = "unknown";
|
|
*freepath = NULL;
|
|
vn_lock(v, LK_CANRECURSE | LK_EXCLUSIVE | LK_RETRY);
|
|
vn_fullpath(curthread, v, fullpath, freepath);
|
|
VOP_UNLOCK(v, 0);
|
|
}
|
|
|
|
/*
|
|
* remove an process owning PMCs
|
|
*/
|
|
|
|
void
|
|
pmc_remove_owner(struct pmc_owner *po)
|
|
{
|
|
struct pmc *pm, *tmp;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
PMCDBG(OWN,ORM,1, "remove-owner po=%p", po);
|
|
|
|
/* Remove descriptor from the owner hash table */
|
|
LIST_REMOVE(po, po_next);
|
|
|
|
/* release all owned PMC descriptors */
|
|
LIST_FOREACH_SAFE(pm, &po->po_pmcs, pm_next, tmp) {
|
|
PMCDBG(OWN,ORM,2, "pmc=%p", pm);
|
|
KASSERT(pm->pm_owner == po,
|
|
("[pmc,%d] owner %p != po %p", __LINE__, pm->pm_owner, po));
|
|
|
|
pmc_release_pmc_descriptor(pm); /* will unlink from the list */
|
|
}
|
|
|
|
KASSERT(po->po_sscount == 0,
|
|
("[pmc,%d] SS count not zero", __LINE__));
|
|
KASSERT(LIST_EMPTY(&po->po_pmcs),
|
|
("[pmc,%d] PMC list not empty", __LINE__));
|
|
|
|
/* de-configure the log file if present */
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_deconfigure_log(po);
|
|
}
|
|
|
|
/*
|
|
* remove an owner process record if all conditions are met.
|
|
*/
|
|
|
|
static void
|
|
pmc_maybe_remove_owner(struct pmc_owner *po)
|
|
{
|
|
|
|
PMCDBG(OWN,OMR,1, "maybe-remove-owner po=%p", po);
|
|
|
|
/*
|
|
* Remove owner record if
|
|
* - this process does not own any PMCs
|
|
* - this process has not allocated a system-wide sampling buffer
|
|
*/
|
|
|
|
if (LIST_EMPTY(&po->po_pmcs) &&
|
|
((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)) {
|
|
pmc_remove_owner(po);
|
|
pmc_destroy_owner_descriptor(po);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Add an association between a target process and a PMC.
|
|
*/
|
|
|
|
static void
|
|
pmc_link_target_process(struct pmc *pm, struct pmc_process *pp)
|
|
{
|
|
int ri;
|
|
struct pmc_target *pt;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
KASSERT(pm != NULL && pp != NULL,
|
|
("[pmc,%d] Null pm %p or pp %p", __LINE__, pm, pp));
|
|
KASSERT(PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)),
|
|
("[pmc,%d] Attaching a non-process-virtual pmc=%p to pid=%d",
|
|
__LINE__, pm, pp->pp_proc->p_pid));
|
|
KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt < ((int) md->pmd_npmc - 1),
|
|
("[pmc,%d] Illegal reference count %d for process record %p",
|
|
__LINE__, pp->pp_refcnt, (void *) pp));
|
|
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
PMCDBG(PRC,TLK,1, "link-target pmc=%p ri=%d pmc-process=%p",
|
|
pm, ri, pp);
|
|
|
|
#ifdef DEBUG
|
|
LIST_FOREACH(pt, &pm->pm_targets, pt_next)
|
|
if (pt->pt_process == pp)
|
|
KASSERT(0, ("[pmc,%d] pp %p already in pmc %p targets",
|
|
__LINE__, pp, pm));
|
|
#endif
|
|
|
|
pt = malloc(sizeof(struct pmc_target), M_PMC, M_ZERO|M_WAITOK);
|
|
|
|
pt->pt_process = pp;
|
|
|
|
LIST_INSERT_HEAD(&pm->pm_targets, pt, pt_next);
|
|
|
|
atomic_store_rel_ptr((uintptr_t *)&pp->pp_pmcs[ri].pp_pmc,
|
|
(uintptr_t)pm);
|
|
|
|
if (pm->pm_owner->po_owner == pp->pp_proc)
|
|
pm->pm_flags |= PMC_F_ATTACHED_TO_OWNER;
|
|
|
|
/*
|
|
* Initialize the per-process values at this row index.
|
|
*/
|
|
pp->pp_pmcs[ri].pp_pmcval = PMC_TO_MODE(pm) == PMC_MODE_TS ?
|
|
pm->pm_sc.pm_reloadcount : 0;
|
|
|
|
pp->pp_refcnt++;
|
|
|
|
}
|
|
|
|
/*
|
|
* Removes the association between a target process and a PMC.
|
|
*/
|
|
|
|
static void
|
|
pmc_unlink_target_process(struct pmc *pm, struct pmc_process *pp)
|
|
{
|
|
int ri;
|
|
struct proc *p;
|
|
struct pmc_target *ptgt;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
KASSERT(pm != NULL && pp != NULL,
|
|
("[pmc,%d] Null pm %p or pp %p", __LINE__, pm, pp));
|
|
|
|
KASSERT(pp->pp_refcnt >= 1 && pp->pp_refcnt < (int) md->pmd_npmc,
|
|
("[pmc,%d] Illegal ref count %d on process record %p",
|
|
__LINE__, pp->pp_refcnt, (void *) pp));
|
|
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
PMCDBG(PRC,TUL,1, "unlink-target pmc=%p ri=%d pmc-process=%p",
|
|
pm, ri, pp);
|
|
|
|
KASSERT(pp->pp_pmcs[ri].pp_pmc == pm,
|
|
("[pmc,%d] PMC ri %d mismatch pmc %p pp->[ri] %p", __LINE__,
|
|
ri, pm, pp->pp_pmcs[ri].pp_pmc));
|
|
|
|
pp->pp_pmcs[ri].pp_pmc = NULL;
|
|
pp->pp_pmcs[ri].pp_pmcval = (pmc_value_t) 0;
|
|
|
|
/* Remove owner-specific flags */
|
|
if (pm->pm_owner->po_owner == pp->pp_proc) {
|
|
pp->pp_flags &= ~PMC_PP_ENABLE_MSR_ACCESS;
|
|
pm->pm_flags &= ~PMC_F_ATTACHED_TO_OWNER;
|
|
}
|
|
|
|
pp->pp_refcnt--;
|
|
|
|
/* Remove the target process from the PMC structure */
|
|
LIST_FOREACH(ptgt, &pm->pm_targets, pt_next)
|
|
if (ptgt->pt_process == pp)
|
|
break;
|
|
|
|
KASSERT(ptgt != NULL, ("[pmc,%d] process %p (pp: %p) not found "
|
|
"in pmc %p", __LINE__, pp->pp_proc, pp, pm));
|
|
|
|
LIST_REMOVE(ptgt, pt_next);
|
|
free(ptgt, M_PMC);
|
|
|
|
/* if the PMC now lacks targets, send the owner a SIGIO */
|
|
if (LIST_EMPTY(&pm->pm_targets)) {
|
|
p = pm->pm_owner->po_owner;
|
|
PROC_LOCK(p);
|
|
psignal(p, SIGIO);
|
|
PROC_UNLOCK(p);
|
|
|
|
PMCDBG(PRC,SIG,2, "signalling proc=%p signal=%d", p,
|
|
SIGIO);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check if PMC 'pm' may be attached to target process 't'.
|
|
*/
|
|
|
|
static int
|
|
pmc_can_attach(struct pmc *pm, struct proc *t)
|
|
{
|
|
struct proc *o; /* pmc owner */
|
|
struct ucred *oc, *tc; /* owner, target credentials */
|
|
int decline_attach, i;
|
|
|
|
/*
|
|
* A PMC's owner can always attach that PMC to itself.
|
|
*/
|
|
|
|
if ((o = pm->pm_owner->po_owner) == t)
|
|
return 0;
|
|
|
|
PROC_LOCK(o);
|
|
oc = o->p_ucred;
|
|
crhold(oc);
|
|
PROC_UNLOCK(o);
|
|
|
|
PROC_LOCK(t);
|
|
tc = t->p_ucred;
|
|
crhold(tc);
|
|
PROC_UNLOCK(t);
|
|
|
|
/*
|
|
* The effective uid of the PMC owner should match at least one
|
|
* of the {effective,real,saved} uids of the target process.
|
|
*/
|
|
|
|
decline_attach = oc->cr_uid != tc->cr_uid &&
|
|
oc->cr_uid != tc->cr_svuid &&
|
|
oc->cr_uid != tc->cr_ruid;
|
|
|
|
/*
|
|
* Every one of the target's group ids, must be in the owner's
|
|
* group list.
|
|
*/
|
|
for (i = 0; !decline_attach && i < tc->cr_ngroups; i++)
|
|
decline_attach = !groupmember(tc->cr_groups[i], oc);
|
|
|
|
/* check the read and saved gids too */
|
|
if (decline_attach == 0)
|
|
decline_attach = !groupmember(tc->cr_rgid, oc) ||
|
|
!groupmember(tc->cr_svgid, oc);
|
|
|
|
crfree(tc);
|
|
crfree(oc);
|
|
|
|
return !decline_attach;
|
|
}
|
|
|
|
/*
|
|
* Attach a process to a PMC.
|
|
*/
|
|
|
|
static int
|
|
pmc_attach_one_process(struct proc *p, struct pmc *pm)
|
|
{
|
|
int ri;
|
|
char *fullpath, *freepath;
|
|
struct pmc_process *pp;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
PMCDBG(PRC,ATT,2, "attach-one pm=%p ri=%d proc=%p (%d, %s)", pm,
|
|
PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm);
|
|
|
|
/*
|
|
* Locate the process descriptor corresponding to process 'p',
|
|
* allocating space as needed.
|
|
*
|
|
* Verify that rowindex 'pm_rowindex' is free in the process
|
|
* descriptor.
|
|
*
|
|
* If not, allocate space for a descriptor and link the
|
|
* process descriptor and PMC.
|
|
*/
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
if ((pp = pmc_find_process_descriptor(p, PMC_FLAG_ALLOCATE)) == NULL)
|
|
return ENOMEM;
|
|
|
|
if (pp->pp_pmcs[ri].pp_pmc == pm) /* already present at slot [ri] */
|
|
return EEXIST;
|
|
|
|
if (pp->pp_pmcs[ri].pp_pmc != NULL)
|
|
return EBUSY;
|
|
|
|
pmc_link_target_process(pm, pp);
|
|
|
|
if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)) &&
|
|
(pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) == 0)
|
|
pm->pm_flags |= PMC_F_NEEDS_LOGFILE;
|
|
|
|
pm->pm_flags |= PMC_F_ATTACH_DONE; /* mark as attached */
|
|
|
|
/* issue an attach event to a configured log file */
|
|
if (pm->pm_owner->po_flags & PMC_PO_OWNS_LOGFILE) {
|
|
pmc_getfilename(p->p_textvp, &fullpath, &freepath);
|
|
if (p->p_flag & P_KTHREAD) {
|
|
fullpath = kernelname;
|
|
freepath = NULL;
|
|
} else
|
|
pmclog_process_pmcattach(pm, p->p_pid, fullpath);
|
|
if (freepath)
|
|
free(freepath, M_TEMP);
|
|
if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
|
|
pmc_log_process_mappings(pm->pm_owner, p);
|
|
}
|
|
/* mark process as using HWPMCs */
|
|
PROC_LOCK(p);
|
|
p->p_flag |= P_HWPMC;
|
|
PROC_UNLOCK(p);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Attach a process and optionally its children
|
|
*/
|
|
|
|
static int
|
|
pmc_attach_process(struct proc *p, struct pmc *pm)
|
|
{
|
|
int error;
|
|
struct proc *top;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
PMCDBG(PRC,ATT,1, "attach pm=%p ri=%d proc=%p (%d, %s)", pm,
|
|
PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm);
|
|
|
|
|
|
/*
|
|
* If this PMC successfully allowed a GETMSR operation
|
|
* in the past, disallow further ATTACHes.
|
|
*/
|
|
|
|
if ((pm->pm_flags & PMC_PP_ENABLE_MSR_ACCESS) != 0)
|
|
return EPERM;
|
|
|
|
if ((pm->pm_flags & PMC_F_DESCENDANTS) == 0)
|
|
return pmc_attach_one_process(p, pm);
|
|
|
|
/*
|
|
* Traverse all child processes, attaching them to
|
|
* this PMC.
|
|
*/
|
|
|
|
sx_slock(&proctree_lock);
|
|
|
|
top = p;
|
|
|
|
for (;;) {
|
|
if ((error = pmc_attach_one_process(p, pm)) != 0)
|
|
break;
|
|
if (!LIST_EMPTY(&p->p_children))
|
|
p = LIST_FIRST(&p->p_children);
|
|
else for (;;) {
|
|
if (p == top)
|
|
goto done;
|
|
if (LIST_NEXT(p, p_sibling)) {
|
|
p = LIST_NEXT(p, p_sibling);
|
|
break;
|
|
}
|
|
p = p->p_pptr;
|
|
}
|
|
}
|
|
|
|
if (error)
|
|
(void) pmc_detach_process(top, pm);
|
|
|
|
done:
|
|
sx_sunlock(&proctree_lock);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Detach a process from a PMC. If there are no other PMCs tracking
|
|
* this process, remove the process structure from its hash table. If
|
|
* 'flags' contains PMC_FLAG_REMOVE, then free the process structure.
|
|
*/
|
|
|
|
static int
|
|
pmc_detach_one_process(struct proc *p, struct pmc *pm, int flags)
|
|
{
|
|
int ri;
|
|
struct pmc_process *pp;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
KASSERT(pm != NULL,
|
|
("[pmc,%d] null pm pointer", __LINE__));
|
|
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
PMCDBG(PRC,ATT,2, "detach-one pm=%p ri=%d proc=%p (%d, %s) flags=0x%x",
|
|
pm, ri, p, p->p_pid, p->p_comm, flags);
|
|
|
|
if ((pp = pmc_find_process_descriptor(p, 0)) == NULL)
|
|
return ESRCH;
|
|
|
|
if (pp->pp_pmcs[ri].pp_pmc != pm)
|
|
return EINVAL;
|
|
|
|
pmc_unlink_target_process(pm, pp);
|
|
|
|
/* Issue a detach entry if a log file is configured */
|
|
if (pm->pm_owner->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_pmcdetach(pm, p->p_pid);
|
|
|
|
/*
|
|
* If there are no PMCs targetting this process, we remove its
|
|
* descriptor from the target hash table and unset the P_HWPMC
|
|
* flag in the struct proc.
|
|
*/
|
|
KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt < (int) md->pmd_npmc,
|
|
("[pmc,%d] Illegal refcnt %d for process struct %p",
|
|
__LINE__, pp->pp_refcnt, pp));
|
|
|
|
if (pp->pp_refcnt != 0) /* still a target of some PMC */
|
|
return 0;
|
|
|
|
pmc_remove_process_descriptor(pp);
|
|
|
|
if (flags & PMC_FLAG_REMOVE)
|
|
free(pp, M_PMC);
|
|
|
|
PROC_LOCK(p);
|
|
p->p_flag &= ~P_HWPMC;
|
|
PROC_UNLOCK(p);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Detach a process and optionally its descendants from a PMC.
|
|
*/
|
|
|
|
static int
|
|
pmc_detach_process(struct proc *p, struct pmc *pm)
|
|
{
|
|
struct proc *top;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
PMCDBG(PRC,ATT,1, "detach pm=%p ri=%d proc=%p (%d, %s)", pm,
|
|
PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm);
|
|
|
|
if ((pm->pm_flags & PMC_F_DESCENDANTS) == 0)
|
|
return pmc_detach_one_process(p, pm, PMC_FLAG_REMOVE);
|
|
|
|
/*
|
|
* Traverse all children, detaching them from this PMC. We
|
|
* ignore errors since we could be detaching a PMC from a
|
|
* partially attached proc tree.
|
|
*/
|
|
|
|
sx_slock(&proctree_lock);
|
|
|
|
top = p;
|
|
|
|
for (;;) {
|
|
(void) pmc_detach_one_process(p, pm, PMC_FLAG_REMOVE);
|
|
|
|
if (!LIST_EMPTY(&p->p_children))
|
|
p = LIST_FIRST(&p->p_children);
|
|
else for (;;) {
|
|
if (p == top)
|
|
goto done;
|
|
if (LIST_NEXT(p, p_sibling)) {
|
|
p = LIST_NEXT(p, p_sibling);
|
|
break;
|
|
}
|
|
p = p->p_pptr;
|
|
}
|
|
}
|
|
|
|
done:
|
|
sx_sunlock(&proctree_lock);
|
|
|
|
if (LIST_EMPTY(&pm->pm_targets))
|
|
pm->pm_flags &= ~PMC_F_ATTACH_DONE;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* Thread context switch IN
|
|
*/
|
|
|
|
static void
|
|
pmc_process_csw_in(struct thread *td)
|
|
{
|
|
int cpu;
|
|
unsigned int ri;
|
|
struct pmc *pm;
|
|
struct proc *p;
|
|
struct pmc_cpu *pc;
|
|
struct pmc_hw *phw;
|
|
struct pmc_process *pp;
|
|
pmc_value_t newvalue;
|
|
|
|
p = td->td_proc;
|
|
|
|
if ((pp = pmc_find_process_descriptor(p, PMC_FLAG_NONE)) == NULL)
|
|
return;
|
|
|
|
KASSERT(pp->pp_proc == td->td_proc,
|
|
("[pmc,%d] not my thread state", __LINE__));
|
|
|
|
critical_enter(); /* no preemption from this point */
|
|
|
|
cpu = PCPU_GET(cpuid); /* td->td_oncpu is invalid */
|
|
|
|
PMCDBG(CSW,SWI,1, "cpu=%d proc=%p (%d, %s) pp=%p", cpu, p,
|
|
p->p_pid, p->p_comm, pp);
|
|
|
|
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
|
|
("[pmc,%d] wierd CPU id %d", __LINE__, cpu));
|
|
|
|
pc = pmc_pcpu[cpu];
|
|
|
|
for (ri = 0; ri < md->pmd_npmc; ri++) {
|
|
|
|
if ((pm = pp->pp_pmcs[ri].pp_pmc) == NULL)
|
|
continue;
|
|
|
|
KASSERT(PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)),
|
|
("[pmc,%d] Target PMC in non-virtual mode (%d)",
|
|
__LINE__, PMC_TO_MODE(pm)));
|
|
|
|
KASSERT(PMC_TO_ROWINDEX(pm) == ri,
|
|
("[pmc,%d] Row index mismatch pmc %d != ri %d",
|
|
__LINE__, PMC_TO_ROWINDEX(pm), ri));
|
|
|
|
/*
|
|
* Only PMCs that are marked as 'RUNNING' need
|
|
* be placed on hardware.
|
|
*/
|
|
|
|
if (pm->pm_state != PMC_STATE_RUNNING)
|
|
continue;
|
|
|
|
/* increment PMC runcount */
|
|
atomic_add_rel_32(&pm->pm_runcount, 1);
|
|
|
|
/* configure the HWPMC we are going to use. */
|
|
md->pmd_config_pmc(cpu, ri, pm);
|
|
|
|
phw = pc->pc_hwpmcs[ri];
|
|
|
|
KASSERT(phw != NULL,
|
|
("[pmc,%d] null hw pointer", __LINE__));
|
|
|
|
KASSERT(phw->phw_pmc == pm,
|
|
("[pmc,%d] hw->pmc %p != pmc %p", __LINE__,
|
|
phw->phw_pmc, pm));
|
|
|
|
/*
|
|
* Write out saved value and start the PMC.
|
|
*
|
|
* Sampling PMCs use a per-process value, while
|
|
* counting mode PMCs use a per-pmc value that is
|
|
* inherited across descendants.
|
|
*/
|
|
if (PMC_TO_MODE(pm) == PMC_MODE_TS) {
|
|
mtx_pool_lock_spin(pmc_mtxpool, pm);
|
|
newvalue = PMC_PCPU_SAVED(cpu,ri) =
|
|
pp->pp_pmcs[ri].pp_pmcval;
|
|
mtx_pool_unlock_spin(pmc_mtxpool, pm);
|
|
} else {
|
|
KASSERT(PMC_TO_MODE(pm) == PMC_MODE_TC,
|
|
("[pmc,%d] illegal mode=%d", __LINE__,
|
|
PMC_TO_MODE(pm)));
|
|
mtx_pool_lock_spin(pmc_mtxpool, pm);
|
|
newvalue = PMC_PCPU_SAVED(cpu, ri) =
|
|
pm->pm_gv.pm_savedvalue;
|
|
mtx_pool_unlock_spin(pmc_mtxpool, pm);
|
|
}
|
|
|
|
PMCDBG(CSW,SWI,1,"cpu=%d ri=%d new=%jd", cpu, ri, newvalue);
|
|
|
|
md->pmd_write_pmc(cpu, ri, newvalue);
|
|
md->pmd_start_pmc(cpu, ri);
|
|
}
|
|
|
|
/*
|
|
* perform any other architecture/cpu dependent thread
|
|
* switch-in actions.
|
|
*/
|
|
|
|
(void) (*md->pmd_switch_in)(pc, pp);
|
|
|
|
critical_exit();
|
|
|
|
}
|
|
|
|
/*
|
|
* Thread context switch OUT.
|
|
*/
|
|
|
|
static void
|
|
pmc_process_csw_out(struct thread *td)
|
|
{
|
|
int cpu;
|
|
enum pmc_mode mode;
|
|
unsigned int ri;
|
|
struct pmc *pm;
|
|
struct proc *p;
|
|
struct pmc_cpu *pc;
|
|
struct pmc_process *pp;
|
|
int64_t tmp;
|
|
pmc_value_t newvalue;
|
|
|
|
/*
|
|
* Locate our process descriptor; this may be NULL if
|
|
* this process is exiting and we have already removed
|
|
* the process from the target process table.
|
|
*
|
|
* Note that due to kernel preemption, multiple
|
|
* context switches may happen while the process is
|
|
* exiting.
|
|
*
|
|
* Note also that if the target process cannot be
|
|
* found we still need to deconfigure any PMCs that
|
|
* are currently running on hardware.
|
|
*/
|
|
|
|
p = td->td_proc;
|
|
pp = pmc_find_process_descriptor(p, PMC_FLAG_NONE);
|
|
|
|
/*
|
|
* save PMCs
|
|
*/
|
|
|
|
critical_enter();
|
|
|
|
cpu = PCPU_GET(cpuid); /* td->td_oncpu is invalid */
|
|
|
|
PMCDBG(CSW,SWO,1, "cpu=%d proc=%p (%d, %s) pp=%p", cpu, p,
|
|
p->p_pid, p->p_comm, pp);
|
|
|
|
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
|
|
("[pmc,%d wierd CPU id %d", __LINE__, cpu));
|
|
|
|
pc = pmc_pcpu[cpu];
|
|
|
|
/*
|
|
* When a PMC gets unlinked from a target PMC, it will
|
|
* be removed from the target's pp_pmc[] array.
|
|
*
|
|
* However, on a MP system, the target could have been
|
|
* executing on another CPU at the time of the unlink.
|
|
* So, at context switch OUT time, we need to look at
|
|
* the hardware to determine if a PMC is scheduled on
|
|
* it.
|
|
*/
|
|
|
|
for (ri = 0; ri < md->pmd_npmc; ri++) {
|
|
|
|
pm = NULL;
|
|
(void) (*md->pmd_get_config)(cpu, ri, &pm);
|
|
|
|
if (pm == NULL) /* nothing at this row index */
|
|
continue;
|
|
|
|
mode = PMC_TO_MODE(pm);
|
|
if (!PMC_IS_VIRTUAL_MODE(mode))
|
|
continue; /* not a process virtual PMC */
|
|
|
|
KASSERT(PMC_TO_ROWINDEX(pm) == ri,
|
|
("[pmc,%d] ri mismatch pmc(%d) ri(%d)",
|
|
__LINE__, PMC_TO_ROWINDEX(pm), ri));
|
|
|
|
/* Stop hardware if not already stopped */
|
|
if (pm->pm_stalled == 0)
|
|
md->pmd_stop_pmc(cpu, ri);
|
|
|
|
/* reduce this PMC's runcount */
|
|
atomic_subtract_rel_32(&pm->pm_runcount, 1);
|
|
|
|
/*
|
|
* If this PMC is associated with this process,
|
|
* save the reading.
|
|
*/
|
|
|
|
if (pp != NULL && pp->pp_pmcs[ri].pp_pmc != NULL) {
|
|
|
|
KASSERT(pm == pp->pp_pmcs[ri].pp_pmc,
|
|
("[pmc,%d] pm %p != pp_pmcs[%d] %p", __LINE__,
|
|
pm, ri, pp->pp_pmcs[ri].pp_pmc));
|
|
|
|
KASSERT(pp->pp_refcnt > 0,
|
|
("[pmc,%d] pp refcnt = %d", __LINE__,
|
|
pp->pp_refcnt));
|
|
|
|
md->pmd_read_pmc(cpu, ri, &newvalue);
|
|
|
|
tmp = newvalue - PMC_PCPU_SAVED(cpu,ri);
|
|
|
|
PMCDBG(CSW,SWI,1,"cpu=%d ri=%d tmp=%jd", cpu, ri,
|
|
tmp);
|
|
|
|
if (mode == PMC_MODE_TS) {
|
|
|
|
/*
|
|
* For sampling process-virtual PMCs,
|
|
* we expect the count to be
|
|
* decreasing as the 'value'
|
|
* programmed into the PMC is the
|
|
* number of events to be seen till
|
|
* the next sampling interrupt.
|
|
*/
|
|
if (tmp < 0)
|
|
tmp += pm->pm_sc.pm_reloadcount;
|
|
mtx_pool_lock_spin(pmc_mtxpool, pm);
|
|
pp->pp_pmcs[ri].pp_pmcval -= tmp;
|
|
if ((int64_t) pp->pp_pmcs[ri].pp_pmcval < 0)
|
|
pp->pp_pmcs[ri].pp_pmcval +=
|
|
pm->pm_sc.pm_reloadcount;
|
|
mtx_pool_unlock_spin(pmc_mtxpool, pm);
|
|
|
|
} else {
|
|
|
|
/*
|
|
* For counting process-virtual PMCs,
|
|
* we expect the count to be
|
|
* increasing monotonically, modulo a 64
|
|
* bit wraparound.
|
|
*/
|
|
KASSERT((int64_t) tmp >= 0,
|
|
("[pmc,%d] negative increment cpu=%d "
|
|
"ri=%d newvalue=%jx saved=%jx "
|
|
"incr=%jx", __LINE__, cpu, ri,
|
|
newvalue, PMC_PCPU_SAVED(cpu,ri), tmp));
|
|
|
|
mtx_pool_lock_spin(pmc_mtxpool, pm);
|
|
pm->pm_gv.pm_savedvalue += tmp;
|
|
pp->pp_pmcs[ri].pp_pmcval += tmp;
|
|
mtx_pool_unlock_spin(pmc_mtxpool, pm);
|
|
|
|
if (pm->pm_flags & PMC_F_LOG_PROCCSW)
|
|
pmclog_process_proccsw(pm, pp, tmp);
|
|
}
|
|
}
|
|
|
|
/* mark hardware as free */
|
|
md->pmd_config_pmc(cpu, ri, NULL);
|
|
}
|
|
|
|
/*
|
|
* perform any other architecture/cpu dependent thread
|
|
* switch out functions.
|
|
*/
|
|
|
|
(void) (*md->pmd_switch_out)(pc, pp);
|
|
|
|
critical_exit();
|
|
}
|
|
|
|
/*
|
|
* Log a KLD operation.
|
|
*/
|
|
|
|
static void
|
|
pmc_process_kld_load(struct pmckern_map_in *pkm)
|
|
{
|
|
struct pmc_owner *po;
|
|
|
|
sx_assert(&pmc_sx, SX_LOCKED);
|
|
|
|
/*
|
|
* Notify owners of system sampling PMCs about KLD operations.
|
|
*/
|
|
|
|
LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_map_in(po, (pid_t) -1, pkm->pm_address,
|
|
(char *) pkm->pm_file);
|
|
|
|
/*
|
|
* TODO: Notify owners of (all) process-sampling PMCs too.
|
|
*/
|
|
|
|
return;
|
|
}
|
|
|
|
static void
|
|
pmc_process_kld_unload(struct pmckern_map_out *pkm)
|
|
{
|
|
struct pmc_owner *po;
|
|
|
|
sx_assert(&pmc_sx, SX_LOCKED);
|
|
|
|
LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_map_out(po, (pid_t) -1,
|
|
pkm->pm_address, pkm->pm_address + pkm->pm_size);
|
|
|
|
/*
|
|
* TODO: Notify owners of process-sampling PMCs.
|
|
*/
|
|
}
|
|
|
|
/*
|
|
* A mapping change for a process.
|
|
*/
|
|
|
|
static void
|
|
pmc_process_mmap(struct thread *td, struct pmckern_map_in *pkm)
|
|
{
|
|
int ri;
|
|
pid_t pid;
|
|
char *fullpath, *freepath;
|
|
const struct pmc *pm;
|
|
struct pmc_owner *po;
|
|
const struct pmc_process *pp;
|
|
|
|
freepath = fullpath = NULL;
|
|
pmc_getfilename((struct vnode *) pkm->pm_file, &fullpath, &freepath);
|
|
|
|
pid = td->td_proc->p_pid;
|
|
|
|
/* Inform owners of all system-wide sampling PMCs. */
|
|
LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_map_in(po, pid, pkm->pm_address, fullpath);
|
|
|
|
if ((pp = pmc_find_process_descriptor(td->td_proc, 0)) == NULL)
|
|
goto done;
|
|
|
|
/*
|
|
* Inform sampling PMC owners tracking this process.
|
|
*/
|
|
for (ri = 0; ri < md->pmd_npmc; ri++)
|
|
if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL &&
|
|
PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
|
|
pmclog_process_map_in(pm->pm_owner,
|
|
pid, pkm->pm_address, fullpath);
|
|
|
|
done:
|
|
if (freepath)
|
|
free(freepath, M_TEMP);
|
|
}
|
|
|
|
|
|
/*
|
|
* Log an munmap request.
|
|
*/
|
|
|
|
static void
|
|
pmc_process_munmap(struct thread *td, struct pmckern_map_out *pkm)
|
|
{
|
|
int ri;
|
|
pid_t pid;
|
|
struct pmc_owner *po;
|
|
const struct pmc *pm;
|
|
const struct pmc_process *pp;
|
|
|
|
pid = td->td_proc->p_pid;
|
|
|
|
LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_map_out(po, pid, pkm->pm_address,
|
|
pkm->pm_address + pkm->pm_size);
|
|
|
|
if ((pp = pmc_find_process_descriptor(td->td_proc, 0)) == NULL)
|
|
return;
|
|
|
|
for (ri = 0; ri < md->pmd_npmc; ri++)
|
|
if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL &&
|
|
PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
|
|
pmclog_process_map_out(pm->pm_owner, pid,
|
|
pkm->pm_address, pkm->pm_address + pkm->pm_size);
|
|
}
|
|
|
|
/*
|
|
* Log mapping information about the kernel.
|
|
*/
|
|
|
|
static void
|
|
pmc_log_kernel_mappings(struct pmc *pm)
|
|
{
|
|
struct pmc_owner *po;
|
|
struct pmckern_map_in *km, *kmbase;
|
|
|
|
sx_assert(&pmc_sx, SX_LOCKED);
|
|
KASSERT(PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)),
|
|
("[pmc,%d] non-sampling PMC (%p) desires mapping information",
|
|
__LINE__, (void *) pm));
|
|
|
|
po = pm->pm_owner;
|
|
|
|
if (po->po_flags & PMC_PO_INITIAL_MAPPINGS_DONE)
|
|
return;
|
|
|
|
/*
|
|
* Log the current set of kernel modules.
|
|
*/
|
|
kmbase = linker_hwpmc_list_objects();
|
|
for (km = kmbase; km->pm_file != NULL; km++) {
|
|
PMCDBG(LOG,REG,1,"%s %p", (char *) km->pm_file,
|
|
(void *) km->pm_address);
|
|
pmclog_process_map_in(po, (pid_t) -1, km->pm_address,
|
|
km->pm_file);
|
|
}
|
|
free(kmbase, M_LINKER);
|
|
|
|
po->po_flags |= PMC_PO_INITIAL_MAPPINGS_DONE;
|
|
}
|
|
|
|
/*
|
|
* Log the mappings for a single process.
|
|
*/
|
|
|
|
static void
|
|
pmc_log_process_mappings(struct pmc_owner *po, struct proc *p)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* Log mappings for all processes in the system.
|
|
*/
|
|
|
|
static void
|
|
pmc_log_all_process_mappings(struct pmc_owner *po)
|
|
{
|
|
struct proc *p, *top;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
if ((p = pfind(1)) == NULL)
|
|
panic("[pmc,%d] Cannot find init", __LINE__);
|
|
|
|
PROC_UNLOCK(p);
|
|
|
|
sx_slock(&proctree_lock);
|
|
|
|
top = p;
|
|
|
|
for (;;) {
|
|
pmc_log_process_mappings(po, p);
|
|
if (!LIST_EMPTY(&p->p_children))
|
|
p = LIST_FIRST(&p->p_children);
|
|
else for (;;) {
|
|
if (p == top)
|
|
goto done;
|
|
if (LIST_NEXT(p, p_sibling)) {
|
|
p = LIST_NEXT(p, p_sibling);
|
|
break;
|
|
}
|
|
p = p->p_pptr;
|
|
}
|
|
}
|
|
done:
|
|
sx_sunlock(&proctree_lock);
|
|
}
|
|
|
|
/*
|
|
* The 'hook' invoked from the kernel proper
|
|
*/
|
|
|
|
|
|
#ifdef DEBUG
|
|
const char *pmc_hooknames[] = {
|
|
/* these strings correspond to PMC_FN_* in <sys/pmckern.h> */
|
|
"",
|
|
"EXEC",
|
|
"CSW-IN",
|
|
"CSW-OUT",
|
|
"SAMPLE",
|
|
"KLDLOAD",
|
|
"KLDUNLOAD",
|
|
"MMAP",
|
|
"MUNMAP",
|
|
"CALLCHAIN"
|
|
};
|
|
#endif
|
|
|
|
static int
|
|
pmc_hook_handler(struct thread *td, int function, void *arg)
|
|
{
|
|
|
|
PMCDBG(MOD,PMH,1, "hook td=%p func=%d \"%s\" arg=%p", td, function,
|
|
pmc_hooknames[function], arg);
|
|
|
|
switch (function)
|
|
{
|
|
|
|
/*
|
|
* Process exec()
|
|
*/
|
|
|
|
case PMC_FN_PROCESS_EXEC:
|
|
{
|
|
char *fullpath, *freepath;
|
|
unsigned int ri;
|
|
int is_using_hwpmcs;
|
|
struct pmc *pm;
|
|
struct proc *p;
|
|
struct pmc_owner *po;
|
|
struct pmc_process *pp;
|
|
struct pmckern_procexec *pk;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
p = td->td_proc;
|
|
pmc_getfilename(p->p_textvp, &fullpath, &freepath);
|
|
|
|
pk = (struct pmckern_procexec *) arg;
|
|
|
|
/* Inform owners of SS mode PMCs of the exec event. */
|
|
LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_procexec(po, PMC_ID_INVALID,
|
|
p->p_pid, pk->pm_entryaddr, fullpath);
|
|
|
|
PROC_LOCK(p);
|
|
is_using_hwpmcs = p->p_flag & P_HWPMC;
|
|
PROC_UNLOCK(p);
|
|
|
|
if (!is_using_hwpmcs) {
|
|
if (freepath)
|
|
free(freepath, M_TEMP);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* PMCs are not inherited across an exec(): remove any
|
|
* PMCs that this process is the owner of.
|
|
*/
|
|
|
|
if ((po = pmc_find_owner_descriptor(p)) != NULL) {
|
|
pmc_remove_owner(po);
|
|
pmc_destroy_owner_descriptor(po);
|
|
}
|
|
|
|
/*
|
|
* If the process being exec'ed is not the target of any
|
|
* PMC, we are done.
|
|
*/
|
|
if ((pp = pmc_find_process_descriptor(p, 0)) == NULL) {
|
|
if (freepath)
|
|
free(freepath, M_TEMP);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Log the exec event to all monitoring owners. Skip
|
|
* owners who have already recieved the event because
|
|
* they had system sampling PMCs active.
|
|
*/
|
|
for (ri = 0; ri < md->pmd_npmc; ri++)
|
|
if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) {
|
|
po = pm->pm_owner;
|
|
if (po->po_sscount == 0 &&
|
|
po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_procexec(po, pm->pm_id,
|
|
p->p_pid, pk->pm_entryaddr,
|
|
fullpath);
|
|
}
|
|
|
|
if (freepath)
|
|
free(freepath, M_TEMP);
|
|
|
|
|
|
PMCDBG(PRC,EXC,1, "exec proc=%p (%d, %s) cred-changed=%d",
|
|
p, p->p_pid, p->p_comm, pk->pm_credentialschanged);
|
|
|
|
if (pk->pm_credentialschanged == 0) /* no change */
|
|
break;
|
|
|
|
/*
|
|
* If the newly exec()'ed process has a different credential
|
|
* than before, allow it to be the target of a PMC only if
|
|
* the PMC's owner has sufficient priviledge.
|
|
*/
|
|
|
|
for (ri = 0; ri < md->pmd_npmc; ri++)
|
|
if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL)
|
|
if (pmc_can_attach(pm, td->td_proc) != 0)
|
|
pmc_detach_one_process(td->td_proc,
|
|
pm, PMC_FLAG_NONE);
|
|
|
|
KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt < (int) md->pmd_npmc,
|
|
("[pmc,%d] Illegal ref count %d on pp %p", __LINE__,
|
|
pp->pp_refcnt, pp));
|
|
|
|
/*
|
|
* If this process is no longer the target of any
|
|
* PMCs, we can remove the process entry and free
|
|
* up space.
|
|
*/
|
|
|
|
if (pp->pp_refcnt == 0) {
|
|
pmc_remove_process_descriptor(pp);
|
|
free(pp, M_PMC);
|
|
break;
|
|
}
|
|
|
|
}
|
|
break;
|
|
|
|
case PMC_FN_CSW_IN:
|
|
pmc_process_csw_in(td);
|
|
break;
|
|
|
|
case PMC_FN_CSW_OUT:
|
|
pmc_process_csw_out(td);
|
|
break;
|
|
|
|
/*
|
|
* Process accumulated PC samples.
|
|
*
|
|
* This function is expected to be called by hardclock() for
|
|
* each CPU that has accumulated PC samples.
|
|
*
|
|
* This function is to be executed on the CPU whose samples
|
|
* are being processed.
|
|
*/
|
|
case PMC_FN_DO_SAMPLES:
|
|
|
|
/*
|
|
* Clear the cpu specific bit in the CPU mask before
|
|
* do the rest of the processing. If the NMI handler
|
|
* gets invoked after the "atomic_clear_int()" call
|
|
* below but before "pmc_process_samples()" gets
|
|
* around to processing the interrupt, then we will
|
|
* come back here at the next hardclock() tick (and
|
|
* may find nothing to do if "pmc_process_samples()"
|
|
* had already processed the interrupt). We don't
|
|
* lose the interrupt sample.
|
|
*/
|
|
atomic_clear_int(&pmc_cpumask, (1 << PCPU_GET(cpuid)));
|
|
pmc_process_samples(PCPU_GET(cpuid));
|
|
break;
|
|
|
|
|
|
case PMC_FN_KLD_LOAD:
|
|
sx_assert(&pmc_sx, SX_LOCKED);
|
|
pmc_process_kld_load((struct pmckern_map_in *) arg);
|
|
break;
|
|
|
|
case PMC_FN_KLD_UNLOAD:
|
|
sx_assert(&pmc_sx, SX_LOCKED);
|
|
pmc_process_kld_unload((struct pmckern_map_out *) arg);
|
|
break;
|
|
|
|
case PMC_FN_MMAP:
|
|
sx_assert(&pmc_sx, SX_LOCKED);
|
|
pmc_process_mmap(td, (struct pmckern_map_in *) arg);
|
|
break;
|
|
|
|
case PMC_FN_MUNMAP:
|
|
sx_assert(&pmc_sx, SX_LOCKED);
|
|
pmc_process_munmap(td, (struct pmckern_map_out *) arg);
|
|
break;
|
|
|
|
case PMC_FN_USER_CALLCHAIN:
|
|
/*
|
|
* Record a call chain.
|
|
*/
|
|
pmc_capture_user_callchain(PCPU_GET(cpuid),
|
|
(struct trapframe *) arg);
|
|
break;
|
|
|
|
default:
|
|
#ifdef DEBUG
|
|
KASSERT(0, ("[pmc,%d] unknown hook %d\n", __LINE__, function));
|
|
#endif
|
|
break;
|
|
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* allocate a 'struct pmc_owner' descriptor in the owner hash table.
|
|
*/
|
|
|
|
static struct pmc_owner *
|
|
pmc_allocate_owner_descriptor(struct proc *p)
|
|
{
|
|
uint32_t hindex;
|
|
struct pmc_owner *po;
|
|
struct pmc_ownerhash *poh;
|
|
|
|
hindex = PMC_HASH_PTR(p, pmc_ownerhashmask);
|
|
poh = &pmc_ownerhash[hindex];
|
|
|
|
/* allocate space for N pointers and one descriptor struct */
|
|
po = malloc(sizeof(struct pmc_owner), M_PMC, M_ZERO|M_WAITOK);
|
|
|
|
po->po_sscount = po->po_error = po->po_flags = 0;
|
|
po->po_file = NULL;
|
|
po->po_owner = p;
|
|
po->po_kthread = NULL;
|
|
LIST_INIT(&po->po_pmcs);
|
|
LIST_INSERT_HEAD(poh, po, po_next); /* insert into hash table */
|
|
|
|
TAILQ_INIT(&po->po_logbuffers);
|
|
mtx_init(&po->po_mtx, "pmc-owner-mtx", "pmc-per-proc", MTX_SPIN);
|
|
|
|
PMCDBG(OWN,ALL,1, "allocate-owner proc=%p (%d, %s) pmc-owner=%p",
|
|
p, p->p_pid, p->p_comm, po);
|
|
|
|
return po;
|
|
}
|
|
|
|
static void
|
|
pmc_destroy_owner_descriptor(struct pmc_owner *po)
|
|
{
|
|
|
|
PMCDBG(OWN,REL,1, "destroy-owner po=%p proc=%p (%d, %s)",
|
|
po, po->po_owner, po->po_owner->p_pid, po->po_owner->p_comm);
|
|
|
|
mtx_destroy(&po->po_mtx);
|
|
free(po, M_PMC);
|
|
}
|
|
|
|
/*
|
|
* find the descriptor corresponding to process 'p', adding or removing it
|
|
* as specified by 'mode'.
|
|
*/
|
|
|
|
static struct pmc_process *
|
|
pmc_find_process_descriptor(struct proc *p, uint32_t mode)
|
|
{
|
|
uint32_t hindex;
|
|
struct pmc_process *pp, *ppnew;
|
|
struct pmc_processhash *pph;
|
|
|
|
hindex = PMC_HASH_PTR(p, pmc_processhashmask);
|
|
pph = &pmc_processhash[hindex];
|
|
|
|
ppnew = NULL;
|
|
|
|
/*
|
|
* Pre-allocate memory in the FIND_ALLOCATE case since we
|
|
* cannot call malloc(9) once we hold a spin lock.
|
|
*/
|
|
|
|
if (mode & PMC_FLAG_ALLOCATE) {
|
|
/* allocate additional space for 'n' pmc pointers */
|
|
ppnew = malloc(sizeof(struct pmc_process) + md->pmd_npmc *
|
|
sizeof(struct pmc_targetstate), M_PMC, M_ZERO|M_WAITOK);
|
|
}
|
|
|
|
mtx_lock_spin(&pmc_processhash_mtx);
|
|
LIST_FOREACH(pp, pph, pp_next)
|
|
if (pp->pp_proc == p)
|
|
break;
|
|
|
|
if ((mode & PMC_FLAG_REMOVE) && pp != NULL)
|
|
LIST_REMOVE(pp, pp_next);
|
|
|
|
if ((mode & PMC_FLAG_ALLOCATE) && pp == NULL &&
|
|
ppnew != NULL) {
|
|
ppnew->pp_proc = p;
|
|
LIST_INSERT_HEAD(pph, ppnew, pp_next);
|
|
pp = ppnew;
|
|
ppnew = NULL;
|
|
}
|
|
mtx_unlock_spin(&pmc_processhash_mtx);
|
|
|
|
if (pp != NULL && ppnew != NULL)
|
|
free(ppnew, M_PMC);
|
|
|
|
return pp;
|
|
}
|
|
|
|
/*
|
|
* remove a process descriptor from the process hash table.
|
|
*/
|
|
|
|
static void
|
|
pmc_remove_process_descriptor(struct pmc_process *pp)
|
|
{
|
|
KASSERT(pp->pp_refcnt == 0,
|
|
("[pmc,%d] Removing process descriptor %p with count %d",
|
|
__LINE__, pp, pp->pp_refcnt));
|
|
|
|
mtx_lock_spin(&pmc_processhash_mtx);
|
|
LIST_REMOVE(pp, pp_next);
|
|
mtx_unlock_spin(&pmc_processhash_mtx);
|
|
}
|
|
|
|
|
|
/*
|
|
* find an owner descriptor corresponding to proc 'p'
|
|
*/
|
|
|
|
static struct pmc_owner *
|
|
pmc_find_owner_descriptor(struct proc *p)
|
|
{
|
|
uint32_t hindex;
|
|
struct pmc_owner *po;
|
|
struct pmc_ownerhash *poh;
|
|
|
|
hindex = PMC_HASH_PTR(p, pmc_ownerhashmask);
|
|
poh = &pmc_ownerhash[hindex];
|
|
|
|
po = NULL;
|
|
LIST_FOREACH(po, poh, po_next)
|
|
if (po->po_owner == p)
|
|
break;
|
|
|
|
PMCDBG(OWN,FND,1, "find-owner proc=%p (%d, %s) hindex=0x%x -> "
|
|
"pmc-owner=%p", p, p->p_pid, p->p_comm, hindex, po);
|
|
|
|
return po;
|
|
}
|
|
|
|
/*
|
|
* pmc_allocate_pmc_descriptor
|
|
*
|
|
* Allocate a pmc descriptor and initialize its
|
|
* fields.
|
|
*/
|
|
|
|
static struct pmc *
|
|
pmc_allocate_pmc_descriptor(void)
|
|
{
|
|
struct pmc *pmc;
|
|
|
|
pmc = malloc(sizeof(struct pmc), M_PMC, M_ZERO|M_WAITOK);
|
|
|
|
if (pmc != NULL) {
|
|
pmc->pm_owner = NULL;
|
|
LIST_INIT(&pmc->pm_targets);
|
|
}
|
|
|
|
PMCDBG(PMC,ALL,1, "allocate-pmc -> pmc=%p", pmc);
|
|
|
|
return pmc;
|
|
}
|
|
|
|
/*
|
|
* Destroy a pmc descriptor.
|
|
*/
|
|
|
|
static void
|
|
pmc_destroy_pmc_descriptor(struct pmc *pm)
|
|
{
|
|
(void) pm;
|
|
|
|
#ifdef DEBUG
|
|
KASSERT(pm->pm_state == PMC_STATE_DELETED ||
|
|
pm->pm_state == PMC_STATE_FREE,
|
|
("[pmc,%d] destroying non-deleted PMC", __LINE__));
|
|
KASSERT(LIST_EMPTY(&pm->pm_targets),
|
|
("[pmc,%d] destroying pmc with targets", __LINE__));
|
|
KASSERT(pm->pm_owner == NULL,
|
|
("[pmc,%d] destroying pmc attached to an owner", __LINE__));
|
|
KASSERT(pm->pm_runcount == 0,
|
|
("[pmc,%d] pmc has non-zero run count %d", __LINE__,
|
|
pm->pm_runcount));
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
pmc_wait_for_pmc_idle(struct pmc *pm)
|
|
{
|
|
#ifdef DEBUG
|
|
volatile int maxloop;
|
|
|
|
maxloop = 100 * pmc_cpu_max();
|
|
#endif
|
|
|
|
/*
|
|
* Loop (with a forced context switch) till the PMC's runcount
|
|
* comes down to zero.
|
|
*/
|
|
while (atomic_load_acq_32(&pm->pm_runcount) > 0) {
|
|
#ifdef DEBUG
|
|
maxloop--;
|
|
KASSERT(maxloop > 0,
|
|
("[pmc,%d] (ri%d, rc%d) waiting too long for "
|
|
"pmc to be free", __LINE__,
|
|
PMC_TO_ROWINDEX(pm), pm->pm_runcount));
|
|
#endif
|
|
pmc_force_context_switch();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This function does the following things:
|
|
*
|
|
* - detaches the PMC from hardware
|
|
* - unlinks all target threads that were attached to it
|
|
* - removes the PMC from its owner's list
|
|
* - destroy's the PMC private mutex
|
|
*
|
|
* Once this function completes, the given pmc pointer can be safely
|
|
* FREE'd by the caller.
|
|
*/
|
|
|
|
static void
|
|
pmc_release_pmc_descriptor(struct pmc *pm)
|
|
{
|
|
u_int ri, cpu;
|
|
enum pmc_mode mode;
|
|
struct pmc_hw *phw;
|
|
struct pmc_owner *po;
|
|
struct pmc_process *pp;
|
|
struct pmc_target *ptgt, *tmp;
|
|
struct pmc_binding pb;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
KASSERT(pm, ("[pmc,%d] null pmc", __LINE__));
|
|
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
mode = PMC_TO_MODE(pm);
|
|
|
|
PMCDBG(PMC,REL,1, "release-pmc pmc=%p ri=%d mode=%d", pm, ri,
|
|
mode);
|
|
|
|
/*
|
|
* First, we take the PMC off hardware.
|
|
*/
|
|
cpu = 0;
|
|
if (PMC_IS_SYSTEM_MODE(mode)) {
|
|
|
|
/*
|
|
* A system mode PMC runs on a specific CPU. Switch
|
|
* to this CPU and turn hardware off.
|
|
*/
|
|
pmc_save_cpu_binding(&pb);
|
|
|
|
cpu = PMC_TO_CPU(pm);
|
|
|
|
pmc_select_cpu(cpu);
|
|
|
|
/* switch off non-stalled CPUs */
|
|
if (pm->pm_state == PMC_STATE_RUNNING &&
|
|
pm->pm_stalled == 0) {
|
|
|
|
phw = pmc_pcpu[cpu]->pc_hwpmcs[ri];
|
|
|
|
KASSERT(phw->phw_pmc == pm,
|
|
("[pmc, %d] pmc ptr ri(%d) hw(%p) pm(%p)",
|
|
__LINE__, ri, phw->phw_pmc, pm));
|
|
PMCDBG(PMC,REL,2, "stopping cpu=%d ri=%d", cpu, ri);
|
|
|
|
critical_enter();
|
|
md->pmd_stop_pmc(cpu, ri);
|
|
critical_exit();
|
|
}
|
|
|
|
PMCDBG(PMC,REL,2, "decfg cpu=%d ri=%d", cpu, ri);
|
|
|
|
critical_enter();
|
|
md->pmd_config_pmc(cpu, ri, NULL);
|
|
critical_exit();
|
|
|
|
/* adjust the global and process count of SS mode PMCs */
|
|
if (mode == PMC_MODE_SS && pm->pm_state == PMC_STATE_RUNNING) {
|
|
po = pm->pm_owner;
|
|
po->po_sscount--;
|
|
if (po->po_sscount == 0) {
|
|
atomic_subtract_rel_int(&pmc_ss_count, 1);
|
|
LIST_REMOVE(po, po_ssnext);
|
|
}
|
|
}
|
|
|
|
pm->pm_state = PMC_STATE_DELETED;
|
|
|
|
pmc_restore_cpu_binding(&pb);
|
|
|
|
/*
|
|
* We could have references to this PMC structure in
|
|
* the per-cpu sample queues. Wait for the queue to
|
|
* drain.
|
|
*/
|
|
pmc_wait_for_pmc_idle(pm);
|
|
|
|
} else if (PMC_IS_VIRTUAL_MODE(mode)) {
|
|
|
|
/*
|
|
* A virtual PMC could be running on multiple CPUs at
|
|
* a given instant.
|
|
*
|
|
* By marking its state as DELETED, we ensure that
|
|
* this PMC is never further scheduled on hardware.
|
|
*
|
|
* Then we wait till all CPUs are done with this PMC.
|
|
*/
|
|
pm->pm_state = PMC_STATE_DELETED;
|
|
|
|
|
|
/* Wait for the PMCs runcount to come to zero. */
|
|
pmc_wait_for_pmc_idle(pm);
|
|
|
|
/*
|
|
* At this point the PMC is off all CPUs and cannot be
|
|
* freshly scheduled onto a CPU. It is now safe to
|
|
* unlink all targets from this PMC. If a
|
|
* process-record's refcount falls to zero, we remove
|
|
* it from the hash table. The module-wide SX lock
|
|
* protects us from races.
|
|
*/
|
|
LIST_FOREACH_SAFE(ptgt, &pm->pm_targets, pt_next, tmp) {
|
|
pp = ptgt->pt_process;
|
|
pmc_unlink_target_process(pm, pp); /* frees 'ptgt' */
|
|
|
|
PMCDBG(PMC,REL,3, "pp->refcnt=%d", pp->pp_refcnt);
|
|
|
|
/*
|
|
* If the target process record shows that no
|
|
* PMCs are attached to it, reclaim its space.
|
|
*/
|
|
|
|
if (pp->pp_refcnt == 0) {
|
|
pmc_remove_process_descriptor(pp);
|
|
free(pp, M_PMC);
|
|
}
|
|
}
|
|
|
|
cpu = curthread->td_oncpu; /* setup cpu for pmd_release() */
|
|
|
|
}
|
|
|
|
/*
|
|
* Release any MD resources
|
|
*/
|
|
|
|
(void) md->pmd_release_pmc(cpu, ri, pm);
|
|
|
|
/*
|
|
* Update row disposition
|
|
*/
|
|
|
|
if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pm)))
|
|
PMC_UNMARK_ROW_STANDALONE(ri);
|
|
else
|
|
PMC_UNMARK_ROW_THREAD(ri);
|
|
|
|
/* unlink from the owner's list */
|
|
if (pm->pm_owner) {
|
|
LIST_REMOVE(pm, pm_next);
|
|
pm->pm_owner = NULL;
|
|
}
|
|
|
|
pmc_destroy_pmc_descriptor(pm);
|
|
}
|
|
|
|
/*
|
|
* Register an owner and a pmc.
|
|
*/
|
|
|
|
static int
|
|
pmc_register_owner(struct proc *p, struct pmc *pmc)
|
|
{
|
|
struct pmc_owner *po;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
if ((po = pmc_find_owner_descriptor(p)) == NULL)
|
|
if ((po = pmc_allocate_owner_descriptor(p)) == NULL)
|
|
return ENOMEM;
|
|
|
|
KASSERT(pmc->pm_owner == NULL,
|
|
("[pmc,%d] attempting to own an initialized PMC", __LINE__));
|
|
pmc->pm_owner = po;
|
|
|
|
LIST_INSERT_HEAD(&po->po_pmcs, pmc, pm_next);
|
|
|
|
PROC_LOCK(p);
|
|
p->p_flag |= P_HWPMC;
|
|
PROC_UNLOCK(p);
|
|
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_pmcallocate(pmc);
|
|
|
|
PMCDBG(PMC,REG,1, "register-owner pmc-owner=%p pmc=%p",
|
|
po, pmc);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Return the current row disposition:
|
|
* == 0 => FREE
|
|
* > 0 => PROCESS MODE
|
|
* < 0 => SYSTEM MODE
|
|
*/
|
|
|
|
int
|
|
pmc_getrowdisp(int ri)
|
|
{
|
|
return pmc_pmcdisp[ri];
|
|
}
|
|
|
|
/*
|
|
* Check if a PMC at row index 'ri' can be allocated to the current
|
|
* process.
|
|
*
|
|
* Allocation can fail if:
|
|
* - the current process is already being profiled by a PMC at index 'ri',
|
|
* attached to it via OP_PMCATTACH.
|
|
* - the current process has already allocated a PMC at index 'ri'
|
|
* via OP_ALLOCATE.
|
|
*/
|
|
|
|
static int
|
|
pmc_can_allocate_rowindex(struct proc *p, unsigned int ri, int cpu)
|
|
{
|
|
enum pmc_mode mode;
|
|
struct pmc *pm;
|
|
struct pmc_owner *po;
|
|
struct pmc_process *pp;
|
|
|
|
PMCDBG(PMC,ALR,1, "can-allocate-rowindex proc=%p (%d, %s) ri=%d "
|
|
"cpu=%d", p, p->p_pid, p->p_comm, ri, cpu);
|
|
|
|
/*
|
|
* We shouldn't have already allocated a process-mode PMC at
|
|
* row index 'ri'.
|
|
*
|
|
* We shouldn't have allocated a system-wide PMC on the same
|
|
* CPU and same RI.
|
|
*/
|
|
if ((po = pmc_find_owner_descriptor(p)) != NULL)
|
|
LIST_FOREACH(pm, &po->po_pmcs, pm_next) {
|
|
if (PMC_TO_ROWINDEX(pm) == ri) {
|
|
mode = PMC_TO_MODE(pm);
|
|
if (PMC_IS_VIRTUAL_MODE(mode))
|
|
return EEXIST;
|
|
if (PMC_IS_SYSTEM_MODE(mode) &&
|
|
(int) PMC_TO_CPU(pm) == cpu)
|
|
return EEXIST;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We also shouldn't be the target of any PMC at this index
|
|
* since otherwise a PMC_ATTACH to ourselves will fail.
|
|
*/
|
|
if ((pp = pmc_find_process_descriptor(p, 0)) != NULL)
|
|
if (pp->pp_pmcs[ri].pp_pmc)
|
|
return EEXIST;
|
|
|
|
PMCDBG(PMC,ALR,2, "can-allocate-rowindex proc=%p (%d, %s) ri=%d ok",
|
|
p, p->p_pid, p->p_comm, ri);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Check if a given PMC at row index 'ri' can be currently used in
|
|
* mode 'mode'.
|
|
*/
|
|
|
|
static int
|
|
pmc_can_allocate_row(int ri, enum pmc_mode mode)
|
|
{
|
|
enum pmc_disp disp;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
PMCDBG(PMC,ALR,1, "can-allocate-row ri=%d mode=%d", ri, mode);
|
|
|
|
if (PMC_IS_SYSTEM_MODE(mode))
|
|
disp = PMC_DISP_STANDALONE;
|
|
else
|
|
disp = PMC_DISP_THREAD;
|
|
|
|
/*
|
|
* check disposition for PMC row 'ri':
|
|
*
|
|
* Expected disposition Row-disposition Result
|
|
*
|
|
* STANDALONE STANDALONE or FREE proceed
|
|
* STANDALONE THREAD fail
|
|
* THREAD THREAD or FREE proceed
|
|
* THREAD STANDALONE fail
|
|
*/
|
|
|
|
if (!PMC_ROW_DISP_IS_FREE(ri) &&
|
|
!(disp == PMC_DISP_THREAD && PMC_ROW_DISP_IS_THREAD(ri)) &&
|
|
!(disp == PMC_DISP_STANDALONE && PMC_ROW_DISP_IS_STANDALONE(ri)))
|
|
return EBUSY;
|
|
|
|
/*
|
|
* All OK
|
|
*/
|
|
|
|
PMCDBG(PMC,ALR,2, "can-allocate-row ri=%d mode=%d ok", ri, mode);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
/*
|
|
* Find a PMC descriptor with user handle 'pmcid' for thread 'td'.
|
|
*/
|
|
|
|
static struct pmc *
|
|
pmc_find_pmc_descriptor_in_process(struct pmc_owner *po, pmc_id_t pmcid)
|
|
{
|
|
struct pmc *pm;
|
|
|
|
KASSERT(PMC_ID_TO_ROWINDEX(pmcid) < md->pmd_npmc,
|
|
("[pmc,%d] Illegal pmc index %d (max %d)", __LINE__,
|
|
PMC_ID_TO_ROWINDEX(pmcid), md->pmd_npmc));
|
|
|
|
LIST_FOREACH(pm, &po->po_pmcs, pm_next)
|
|
if (pm->pm_id == pmcid)
|
|
return pm;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int
|
|
pmc_find_pmc(pmc_id_t pmcid, struct pmc **pmc)
|
|
{
|
|
|
|
struct pmc *pm;
|
|
struct pmc_owner *po;
|
|
|
|
PMCDBG(PMC,FND,1, "find-pmc id=%d", pmcid);
|
|
|
|
if ((po = pmc_find_owner_descriptor(curthread->td_proc)) == NULL)
|
|
return ESRCH;
|
|
|
|
if ((pm = pmc_find_pmc_descriptor_in_process(po, pmcid)) == NULL)
|
|
return EINVAL;
|
|
|
|
PMCDBG(PMC,FND,2, "find-pmc id=%d -> pmc=%p", pmcid, pm);
|
|
|
|
*pmc = pm;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Start a PMC.
|
|
*/
|
|
|
|
static int
|
|
pmc_start(struct pmc *pm)
|
|
{
|
|
int error, cpu, ri;
|
|
enum pmc_mode mode;
|
|
struct pmc_owner *po;
|
|
struct pmc_binding pb;
|
|
|
|
KASSERT(pm != NULL,
|
|
("[pmc,%d] null pm", __LINE__));
|
|
|
|
mode = PMC_TO_MODE(pm);
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
error = 0;
|
|
|
|
PMCDBG(PMC,OPS,1, "start pmc=%p mode=%d ri=%d", pm, mode, ri);
|
|
|
|
po = pm->pm_owner;
|
|
|
|
/*
|
|
* Disallow PMCSTART if a logfile is required but has not been
|
|
* configured yet.
|
|
*/
|
|
if ((pm->pm_flags & PMC_F_NEEDS_LOGFILE) &&
|
|
(po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
|
|
return EDOOFUS; /* programming error */
|
|
|
|
/*
|
|
* If this is a sampling mode PMC, log mapping information for
|
|
* the kernel modules that are currently loaded.
|
|
*/
|
|
if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
|
|
pmc_log_kernel_mappings(pm);
|
|
|
|
if (PMC_IS_VIRTUAL_MODE(mode)) {
|
|
|
|
/*
|
|
* If a PMCATTACH has never been done on this PMC,
|
|
* attach it to its owner process.
|
|
*/
|
|
|
|
if (LIST_EMPTY(&pm->pm_targets))
|
|
error = (pm->pm_flags & PMC_F_ATTACH_DONE) ? ESRCH :
|
|
pmc_attach_process(po->po_owner, pm);
|
|
|
|
/*
|
|
* If the PMC is attached to its owner, then force a context
|
|
* switch to ensure that the MD state gets set correctly.
|
|
*/
|
|
|
|
if (error == 0) {
|
|
pm->pm_state = PMC_STATE_RUNNING;
|
|
if (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER)
|
|
pmc_force_context_switch();
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
|
|
/*
|
|
* A system-wide PMC.
|
|
*
|
|
* Add the owner to the global list if this is a system-wide
|
|
* sampling PMC.
|
|
*/
|
|
|
|
if (mode == PMC_MODE_SS) {
|
|
if (po->po_sscount == 0) {
|
|
LIST_INSERT_HEAD(&pmc_ss_owners, po, po_ssnext);
|
|
atomic_add_rel_int(&pmc_ss_count, 1);
|
|
PMCDBG(PMC,OPS,1, "po=%p in global list", po);
|
|
}
|
|
po->po_sscount++;
|
|
}
|
|
|
|
/* Log mapping information for all processes in the system. */
|
|
pmc_log_all_process_mappings(po);
|
|
|
|
/*
|
|
* Move to the CPU associated with this
|
|
* PMC, and start the hardware.
|
|
*/
|
|
|
|
pmc_save_cpu_binding(&pb);
|
|
|
|
cpu = PMC_TO_CPU(pm);
|
|
|
|
if (!pmc_cpu_is_active(cpu))
|
|
return ENXIO;
|
|
|
|
pmc_select_cpu(cpu);
|
|
|
|
/*
|
|
* global PMCs are configured at allocation time
|
|
* so write out the initial value and start the PMC.
|
|
*/
|
|
|
|
pm->pm_state = PMC_STATE_RUNNING;
|
|
|
|
critical_enter();
|
|
if ((error = md->pmd_write_pmc(cpu, ri,
|
|
PMC_IS_SAMPLING_MODE(mode) ?
|
|
pm->pm_sc.pm_reloadcount :
|
|
pm->pm_sc.pm_initial)) == 0)
|
|
error = md->pmd_start_pmc(cpu, ri);
|
|
critical_exit();
|
|
|
|
pmc_restore_cpu_binding(&pb);
|
|
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Stop a PMC.
|
|
*/
|
|
|
|
static int
|
|
pmc_stop(struct pmc *pm)
|
|
{
|
|
int cpu, error, ri;
|
|
struct pmc_owner *po;
|
|
struct pmc_binding pb;
|
|
|
|
KASSERT(pm != NULL, ("[pmc,%d] null pmc", __LINE__));
|
|
|
|
PMCDBG(PMC,OPS,1, "stop pmc=%p mode=%d ri=%d", pm,
|
|
PMC_TO_MODE(pm), PMC_TO_ROWINDEX(pm));
|
|
|
|
pm->pm_state = PMC_STATE_STOPPED;
|
|
|
|
/*
|
|
* If the PMC is a virtual mode one, changing the state to
|
|
* non-RUNNING is enough to ensure that the PMC never gets
|
|
* scheduled.
|
|
*
|
|
* If this PMC is current running on a CPU, then it will
|
|
* handled correctly at the time its target process is context
|
|
* switched out.
|
|
*/
|
|
|
|
if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)))
|
|
return 0;
|
|
|
|
/*
|
|
* A system-mode PMC. Move to the CPU associated with
|
|
* this PMC, and stop the hardware. We update the
|
|
* 'initial count' so that a subsequent PMCSTART will
|
|
* resume counting from the current hardware count.
|
|
*/
|
|
|
|
pmc_save_cpu_binding(&pb);
|
|
|
|
cpu = PMC_TO_CPU(pm);
|
|
|
|
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
|
|
("[pmc,%d] illegal cpu=%d", __LINE__, cpu));
|
|
|
|
if (!pmc_cpu_is_active(cpu))
|
|
return ENXIO;
|
|
|
|
pmc_select_cpu(cpu);
|
|
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
critical_enter();
|
|
if ((error = md->pmd_stop_pmc(cpu, ri)) == 0)
|
|
error = md->pmd_read_pmc(cpu, ri, &pm->pm_sc.pm_initial);
|
|
critical_exit();
|
|
|
|
pmc_restore_cpu_binding(&pb);
|
|
|
|
po = pm->pm_owner;
|
|
|
|
/* remove this owner from the global list of SS PMC owners */
|
|
if (PMC_TO_MODE(pm) == PMC_MODE_SS) {
|
|
po->po_sscount--;
|
|
if (po->po_sscount == 0) {
|
|
atomic_subtract_rel_int(&pmc_ss_count, 1);
|
|
LIST_REMOVE(po, po_ssnext);
|
|
PMCDBG(PMC,OPS,2,"po=%p removed from global list", po);
|
|
}
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
|
|
#ifdef DEBUG
|
|
static const char *pmc_op_to_name[] = {
|
|
#undef __PMC_OP
|
|
#define __PMC_OP(N, D) #N ,
|
|
__PMC_OPS()
|
|
NULL
|
|
};
|
|
#endif
|
|
|
|
/*
|
|
* The syscall interface
|
|
*/
|
|
|
|
#define PMC_GET_SX_XLOCK(...) do { \
|
|
sx_xlock(&pmc_sx); \
|
|
if (pmc_hook == NULL) { \
|
|
sx_xunlock(&pmc_sx); \
|
|
return __VA_ARGS__; \
|
|
} \
|
|
} while (0)
|
|
|
|
#define PMC_DOWNGRADE_SX() do { \
|
|
sx_downgrade(&pmc_sx); \
|
|
is_sx_downgraded = 1; \
|
|
} while (0)
|
|
|
|
static int
|
|
pmc_syscall_handler(struct thread *td, void *syscall_args)
|
|
{
|
|
int error, is_sx_downgraded, op;
|
|
struct pmc_syscall_args *c;
|
|
void *arg;
|
|
|
|
PMC_GET_SX_XLOCK(ENOSYS);
|
|
|
|
DROP_GIANT();
|
|
|
|
is_sx_downgraded = 0;
|
|
|
|
c = (struct pmc_syscall_args *) syscall_args;
|
|
|
|
op = c->pmop_code;
|
|
arg = c->pmop_data;
|
|
|
|
PMCDBG(MOD,PMS,1, "syscall op=%d \"%s\" arg=%p", op,
|
|
pmc_op_to_name[op], arg);
|
|
|
|
error = 0;
|
|
atomic_add_int(&pmc_stats.pm_syscalls, 1);
|
|
|
|
switch(op)
|
|
{
|
|
|
|
|
|
/*
|
|
* Configure a log file.
|
|
*
|
|
* XXX This OP will be reworked.
|
|
*/
|
|
|
|
case PMC_OP_CONFIGURELOG:
|
|
{
|
|
struct proc *p;
|
|
struct pmc *pm;
|
|
struct pmc_owner *po;
|
|
struct pmc_op_configurelog cl;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
if ((error = copyin(arg, &cl, sizeof(cl))) != 0)
|
|
break;
|
|
|
|
/* mark this process as owning a log file */
|
|
p = td->td_proc;
|
|
if ((po = pmc_find_owner_descriptor(p)) == NULL)
|
|
if ((po = pmc_allocate_owner_descriptor(p)) == NULL) {
|
|
error = ENOMEM;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* If a valid fd was passed in, try to configure that,
|
|
* otherwise if 'fd' was less than zero and there was
|
|
* a log file configured, flush its buffers and
|
|
* de-configure it.
|
|
*/
|
|
if (cl.pm_logfd >= 0)
|
|
error = pmclog_configure_log(po, cl.pm_logfd);
|
|
else if (po->po_flags & PMC_PO_OWNS_LOGFILE) {
|
|
pmclog_process_closelog(po);
|
|
error = pmclog_flush(po);
|
|
if (error == 0) {
|
|
LIST_FOREACH(pm, &po->po_pmcs, pm_next)
|
|
if (pm->pm_flags & PMC_F_NEEDS_LOGFILE &&
|
|
pm->pm_state == PMC_STATE_RUNNING)
|
|
pmc_stop(pm);
|
|
error = pmclog_deconfigure_log(po);
|
|
}
|
|
} else
|
|
error = EINVAL;
|
|
|
|
if (error)
|
|
break;
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Flush a log file.
|
|
*/
|
|
|
|
case PMC_OP_FLUSHLOG:
|
|
{
|
|
struct pmc_owner *po;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
error = pmclog_flush(po);
|
|
}
|
|
break;
|
|
|
|
/*
|
|
* Retrieve hardware configuration.
|
|
*/
|
|
|
|
case PMC_OP_GETCPUINFO: /* CPU information */
|
|
{
|
|
struct pmc_op_getcpuinfo gci;
|
|
|
|
gci.pm_cputype = md->pmd_cputype;
|
|
gci.pm_ncpu = pmc_cpu_max();
|
|
gci.pm_npmc = md->pmd_npmc;
|
|
gci.pm_nclass = md->pmd_nclass;
|
|
bcopy(md->pmd_classes, &gci.pm_classes,
|
|
sizeof(gci.pm_classes));
|
|
error = copyout(&gci, arg, sizeof(gci));
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Get module statistics
|
|
*/
|
|
|
|
case PMC_OP_GETDRIVERSTATS:
|
|
{
|
|
struct pmc_op_getdriverstats gms;
|
|
|
|
bcopy(&pmc_stats, &gms, sizeof(gms));
|
|
error = copyout(&gms, arg, sizeof(gms));
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Retrieve module version number
|
|
*/
|
|
|
|
case PMC_OP_GETMODULEVERSION:
|
|
{
|
|
uint32_t cv, modv;
|
|
|
|
/* retrieve the client's idea of the ABI version */
|
|
if ((error = copyin(arg, &cv, sizeof(uint32_t))) != 0)
|
|
break;
|
|
/* don't service clients newer than our driver */
|
|
modv = PMC_VERSION;
|
|
if ((cv & 0xFFFF0000) > (modv & 0xFFFF0000)) {
|
|
error = EPROGMISMATCH;
|
|
break;
|
|
}
|
|
error = copyout(&modv, arg, sizeof(int));
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Retrieve the state of all the PMCs on a given
|
|
* CPU.
|
|
*/
|
|
|
|
case PMC_OP_GETPMCINFO:
|
|
{
|
|
uint32_t cpu, n, npmc;
|
|
size_t pmcinfo_size;
|
|
struct pmc *pm;
|
|
struct pmc_info *p, *pmcinfo;
|
|
struct pmc_op_getpmcinfo *gpi;
|
|
struct pmc_owner *po;
|
|
struct pmc_binding pb;
|
|
|
|
PMC_DOWNGRADE_SX();
|
|
|
|
gpi = (struct pmc_op_getpmcinfo *) arg;
|
|
|
|
if ((error = copyin(&gpi->pm_cpu, &cpu, sizeof(cpu))) != 0)
|
|
break;
|
|
|
|
if (cpu >= pmc_cpu_max()) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (!pmc_cpu_is_active(cpu)) {
|
|
error = ENXIO;
|
|
break;
|
|
}
|
|
|
|
/* switch to CPU 'cpu' */
|
|
pmc_save_cpu_binding(&pb);
|
|
pmc_select_cpu(cpu);
|
|
|
|
npmc = md->pmd_npmc;
|
|
|
|
pmcinfo_size = npmc * sizeof(struct pmc_info);
|
|
pmcinfo = malloc(pmcinfo_size, M_PMC, M_WAITOK);
|
|
|
|
p = pmcinfo;
|
|
|
|
for (n = 0; n < md->pmd_npmc; n++, p++) {
|
|
|
|
if ((error = md->pmd_describe(cpu, n, p, &pm)) != 0)
|
|
break;
|
|
|
|
if (PMC_ROW_DISP_IS_STANDALONE(n))
|
|
p->pm_rowdisp = PMC_DISP_STANDALONE;
|
|
else if (PMC_ROW_DISP_IS_THREAD(n))
|
|
p->pm_rowdisp = PMC_DISP_THREAD;
|
|
else
|
|
p->pm_rowdisp = PMC_DISP_FREE;
|
|
|
|
p->pm_ownerpid = -1;
|
|
|
|
if (pm == NULL) /* no PMC associated */
|
|
continue;
|
|
|
|
po = pm->pm_owner;
|
|
|
|
KASSERT(po->po_owner != NULL,
|
|
("[pmc,%d] pmc_owner had a null proc pointer",
|
|
__LINE__));
|
|
|
|
p->pm_ownerpid = po->po_owner->p_pid;
|
|
p->pm_mode = PMC_TO_MODE(pm);
|
|
p->pm_event = pm->pm_event;
|
|
p->pm_flags = pm->pm_flags;
|
|
|
|
if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
|
|
p->pm_reloadcount =
|
|
pm->pm_sc.pm_reloadcount;
|
|
}
|
|
|
|
pmc_restore_cpu_binding(&pb);
|
|
|
|
/* now copy out the PMC info collected */
|
|
if (error == 0)
|
|
error = copyout(pmcinfo, &gpi->pm_pmcs, pmcinfo_size);
|
|
|
|
free(pmcinfo, M_PMC);
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Set the administrative state of a PMC. I.e. whether
|
|
* the PMC is to be used or not.
|
|
*/
|
|
|
|
case PMC_OP_PMCADMIN:
|
|
{
|
|
int cpu, ri;
|
|
enum pmc_state request;
|
|
struct pmc_cpu *pc;
|
|
struct pmc_hw *phw;
|
|
struct pmc_op_pmcadmin pma;
|
|
struct pmc_binding pb;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
KASSERT(td == curthread,
|
|
("[pmc,%d] td != curthread", __LINE__));
|
|
|
|
error = priv_check(td, PRIV_PMC_MANAGE);
|
|
if (error)
|
|
break;
|
|
|
|
if ((error = copyin(arg, &pma, sizeof(pma))) != 0)
|
|
break;
|
|
|
|
cpu = pma.pm_cpu;
|
|
|
|
if (cpu < 0 || cpu >= (int) pmc_cpu_max()) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (!pmc_cpu_is_active(cpu)) {
|
|
error = ENXIO;
|
|
break;
|
|
}
|
|
|
|
request = pma.pm_state;
|
|
|
|
if (request != PMC_STATE_DISABLED &&
|
|
request != PMC_STATE_FREE) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
ri = pma.pm_pmc; /* pmc id == row index */
|
|
if (ri < 0 || ri >= (int) md->pmd_npmc) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* We can't disable a PMC with a row-index allocated
|
|
* for process virtual PMCs.
|
|
*/
|
|
|
|
if (PMC_ROW_DISP_IS_THREAD(ri) &&
|
|
request == PMC_STATE_DISABLED) {
|
|
error = EBUSY;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* otherwise, this PMC on this CPU is either free or
|
|
* in system-wide mode.
|
|
*/
|
|
|
|
pmc_save_cpu_binding(&pb);
|
|
pmc_select_cpu(cpu);
|
|
|
|
pc = pmc_pcpu[cpu];
|
|
phw = pc->pc_hwpmcs[ri];
|
|
|
|
/*
|
|
* XXX do we need some kind of 'forced' disable?
|
|
*/
|
|
|
|
if (phw->phw_pmc == NULL) {
|
|
if (request == PMC_STATE_DISABLED &&
|
|
(phw->phw_state & PMC_PHW_FLAG_IS_ENABLED)) {
|
|
phw->phw_state &= ~PMC_PHW_FLAG_IS_ENABLED;
|
|
PMC_MARK_ROW_STANDALONE(ri);
|
|
} else if (request == PMC_STATE_FREE &&
|
|
(phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) == 0) {
|
|
phw->phw_state |= PMC_PHW_FLAG_IS_ENABLED;
|
|
PMC_UNMARK_ROW_STANDALONE(ri);
|
|
}
|
|
/* other cases are a no-op */
|
|
} else
|
|
error = EBUSY;
|
|
|
|
pmc_restore_cpu_binding(&pb);
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Allocate a PMC.
|
|
*/
|
|
|
|
case PMC_OP_PMCALLOCATE:
|
|
{
|
|
uint32_t caps;
|
|
u_int cpu;
|
|
int n;
|
|
enum pmc_mode mode;
|
|
struct pmc *pmc;
|
|
struct pmc_hw *phw;
|
|
struct pmc_op_pmcallocate pa;
|
|
struct pmc_binding pb;
|
|
|
|
if ((error = copyin(arg, &pa, sizeof(pa))) != 0)
|
|
break;
|
|
|
|
caps = pa.pm_caps;
|
|
mode = pa.pm_mode;
|
|
cpu = pa.pm_cpu;
|
|
|
|
if ((mode != PMC_MODE_SS && mode != PMC_MODE_SC &&
|
|
mode != PMC_MODE_TS && mode != PMC_MODE_TC) ||
|
|
(cpu != (u_int) PMC_CPU_ANY && cpu >= pmc_cpu_max())) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Virtual PMCs should only ask for a default CPU.
|
|
* System mode PMCs need to specify a non-default CPU.
|
|
*/
|
|
|
|
if ((PMC_IS_VIRTUAL_MODE(mode) && cpu != (u_int) PMC_CPU_ANY) ||
|
|
(PMC_IS_SYSTEM_MODE(mode) && cpu == (u_int) PMC_CPU_ANY)) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Check that an inactive CPU is not being asked for.
|
|
*/
|
|
|
|
if (PMC_IS_SYSTEM_MODE(mode) && !pmc_cpu_is_active(cpu)) {
|
|
error = ENXIO;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Refuse an allocation for a system-wide PMC if this
|
|
* process has been jailed, or if this process lacks
|
|
* super-user credentials and the sysctl tunable
|
|
* 'security.bsd.unprivileged_syspmcs' is zero.
|
|
*/
|
|
|
|
if (PMC_IS_SYSTEM_MODE(mode)) {
|
|
if (jailed(curthread->td_ucred)) {
|
|
error = EPERM;
|
|
break;
|
|
}
|
|
if (!pmc_unprivileged_syspmcs) {
|
|
error = priv_check(curthread,
|
|
PRIV_PMC_SYSTEM);
|
|
if (error)
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (error)
|
|
break;
|
|
|
|
/*
|
|
* Look for valid values for 'pm_flags'
|
|
*/
|
|
|
|
if ((pa.pm_flags & ~(PMC_F_DESCENDANTS | PMC_F_LOG_PROCCSW |
|
|
PMC_F_LOG_PROCEXIT | PMC_F_CALLCHAIN)) != 0) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* process logging options are not allowed for system PMCs */
|
|
if (PMC_IS_SYSTEM_MODE(mode) && (pa.pm_flags &
|
|
(PMC_F_LOG_PROCCSW | PMC_F_LOG_PROCEXIT))) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* All sampling mode PMCs need to be able to interrupt the
|
|
* CPU.
|
|
*/
|
|
if (PMC_IS_SAMPLING_MODE(mode))
|
|
caps |= PMC_CAP_INTERRUPT;
|
|
|
|
/* A valid class specifier should have been passed in. */
|
|
for (n = 0; n < md->pmd_nclass; n++)
|
|
if (md->pmd_classes[n].pm_class == pa.pm_class)
|
|
break;
|
|
if (n == md->pmd_nclass) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* The requested PMC capabilities should be feasible. */
|
|
if ((md->pmd_classes[n].pm_caps & caps) != caps) {
|
|
error = EOPNOTSUPP;
|
|
break;
|
|
}
|
|
|
|
PMCDBG(PMC,ALL,2, "event=%d caps=0x%x mode=%d cpu=%d",
|
|
pa.pm_ev, caps, mode, cpu);
|
|
|
|
pmc = pmc_allocate_pmc_descriptor();
|
|
pmc->pm_id = PMC_ID_MAKE_ID(cpu,pa.pm_mode,pa.pm_class,
|
|
PMC_ID_INVALID);
|
|
pmc->pm_event = pa.pm_ev;
|
|
pmc->pm_state = PMC_STATE_FREE;
|
|
pmc->pm_caps = caps;
|
|
pmc->pm_flags = pa.pm_flags;
|
|
|
|
/* switch thread to CPU 'cpu' */
|
|
pmc_save_cpu_binding(&pb);
|
|
|
|
#define PMC_IS_SHAREABLE_PMC(cpu, n) \
|
|
(pmc_pcpu[(cpu)]->pc_hwpmcs[(n)]->phw_state & \
|
|
PMC_PHW_FLAG_IS_SHAREABLE)
|
|
#define PMC_IS_UNALLOCATED(cpu, n) \
|
|
(pmc_pcpu[(cpu)]->pc_hwpmcs[(n)]->phw_pmc == NULL)
|
|
|
|
if (PMC_IS_SYSTEM_MODE(mode)) {
|
|
pmc_select_cpu(cpu);
|
|
for (n = 0; n < (int) md->pmd_npmc; n++)
|
|
if (pmc_can_allocate_row(n, mode) == 0 &&
|
|
pmc_can_allocate_rowindex(
|
|
curthread->td_proc, n, cpu) == 0 &&
|
|
(PMC_IS_UNALLOCATED(cpu, n) ||
|
|
PMC_IS_SHAREABLE_PMC(cpu, n)) &&
|
|
md->pmd_allocate_pmc(cpu, n, pmc,
|
|
&pa) == 0)
|
|
break;
|
|
} else {
|
|
/* Process virtual mode */
|
|
for (n = 0; n < (int) md->pmd_npmc; n++) {
|
|
if (pmc_can_allocate_row(n, mode) == 0 &&
|
|
pmc_can_allocate_rowindex(
|
|
curthread->td_proc, n,
|
|
PMC_CPU_ANY) == 0 &&
|
|
md->pmd_allocate_pmc(curthread->td_oncpu,
|
|
n, pmc, &pa) == 0)
|
|
break;
|
|
}
|
|
}
|
|
|
|
#undef PMC_IS_UNALLOCATED
|
|
#undef PMC_IS_SHAREABLE_PMC
|
|
|
|
pmc_restore_cpu_binding(&pb);
|
|
|
|
if (n == (int) md->pmd_npmc) {
|
|
pmc_destroy_pmc_descriptor(pmc);
|
|
free(pmc, M_PMC);
|
|
pmc = NULL;
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* Fill in the correct value in the ID field */
|
|
pmc->pm_id = PMC_ID_MAKE_ID(cpu,mode,pa.pm_class,n);
|
|
|
|
PMCDBG(PMC,ALL,2, "ev=%d class=%d mode=%d n=%d -> pmcid=%x",
|
|
pmc->pm_event, pa.pm_class, mode, n, pmc->pm_id);
|
|
|
|
/* Process mode PMCs with logging enabled need log files */
|
|
if (pmc->pm_flags & (PMC_F_LOG_PROCEXIT | PMC_F_LOG_PROCCSW))
|
|
pmc->pm_flags |= PMC_F_NEEDS_LOGFILE;
|
|
|
|
/* All system mode sampling PMCs require a log file */
|
|
if (PMC_IS_SAMPLING_MODE(mode) && PMC_IS_SYSTEM_MODE(mode))
|
|
pmc->pm_flags |= PMC_F_NEEDS_LOGFILE;
|
|
|
|
/*
|
|
* Configure global pmc's immediately
|
|
*/
|
|
|
|
if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pmc))) {
|
|
|
|
pmc_save_cpu_binding(&pb);
|
|
pmc_select_cpu(cpu);
|
|
|
|
phw = pmc_pcpu[cpu]->pc_hwpmcs[n];
|
|
|
|
if ((phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) == 0 ||
|
|
(error = md->pmd_config_pmc(cpu, n, pmc)) != 0) {
|
|
(void) md->pmd_release_pmc(cpu, n, pmc);
|
|
pmc_destroy_pmc_descriptor(pmc);
|
|
free(pmc, M_PMC);
|
|
pmc = NULL;
|
|
pmc_restore_cpu_binding(&pb);
|
|
error = EPERM;
|
|
break;
|
|
}
|
|
|
|
pmc_restore_cpu_binding(&pb);
|
|
}
|
|
|
|
pmc->pm_state = PMC_STATE_ALLOCATED;
|
|
|
|
/*
|
|
* mark row disposition
|
|
*/
|
|
|
|
if (PMC_IS_SYSTEM_MODE(mode))
|
|
PMC_MARK_ROW_STANDALONE(n);
|
|
else
|
|
PMC_MARK_ROW_THREAD(n);
|
|
|
|
/*
|
|
* Register this PMC with the current thread as its owner.
|
|
*/
|
|
|
|
if ((error =
|
|
pmc_register_owner(curthread->td_proc, pmc)) != 0) {
|
|
pmc_release_pmc_descriptor(pmc);
|
|
free(pmc, M_PMC);
|
|
pmc = NULL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Return the allocated index.
|
|
*/
|
|
|
|
pa.pm_pmcid = pmc->pm_id;
|
|
|
|
error = copyout(&pa, arg, sizeof(pa));
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Attach a PMC to a process.
|
|
*/
|
|
|
|
case PMC_OP_PMCATTACH:
|
|
{
|
|
struct pmc *pm;
|
|
struct proc *p;
|
|
struct pmc_op_pmcattach a;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
if ((error = copyin(arg, &a, sizeof(a))) != 0)
|
|
break;
|
|
|
|
if (a.pm_pid < 0) {
|
|
error = EINVAL;
|
|
break;
|
|
} else if (a.pm_pid == 0)
|
|
a.pm_pid = td->td_proc->p_pid;
|
|
|
|
if ((error = pmc_find_pmc(a.pm_pmc, &pm)) != 0)
|
|
break;
|
|
|
|
if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pm))) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* PMCs may be (re)attached only when allocated or stopped */
|
|
if (pm->pm_state == PMC_STATE_RUNNING) {
|
|
error = EBUSY;
|
|
break;
|
|
} else if (pm->pm_state != PMC_STATE_ALLOCATED &&
|
|
pm->pm_state != PMC_STATE_STOPPED) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* lookup pid */
|
|
if ((p = pfind(a.pm_pid)) == NULL) {
|
|
error = ESRCH;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Ignore processes that are working on exiting.
|
|
*/
|
|
if (p->p_flag & P_WEXIT) {
|
|
error = ESRCH;
|
|
PROC_UNLOCK(p); /* pfind() returns a locked process */
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* we are allowed to attach a PMC to a process if
|
|
* we can debug it.
|
|
*/
|
|
error = p_candebug(curthread, p);
|
|
|
|
PROC_UNLOCK(p);
|
|
|
|
if (error == 0)
|
|
error = pmc_attach_process(p, pm);
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Detach an attached PMC from a process.
|
|
*/
|
|
|
|
case PMC_OP_PMCDETACH:
|
|
{
|
|
struct pmc *pm;
|
|
struct proc *p;
|
|
struct pmc_op_pmcattach a;
|
|
|
|
if ((error = copyin(arg, &a, sizeof(a))) != 0)
|
|
break;
|
|
|
|
if (a.pm_pid < 0) {
|
|
error = EINVAL;
|
|
break;
|
|
} else if (a.pm_pid == 0)
|
|
a.pm_pid = td->td_proc->p_pid;
|
|
|
|
if ((error = pmc_find_pmc(a.pm_pmc, &pm)) != 0)
|
|
break;
|
|
|
|
if ((p = pfind(a.pm_pid)) == NULL) {
|
|
error = ESRCH;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Treat processes that are in the process of exiting
|
|
* as if they were not present.
|
|
*/
|
|
|
|
if (p->p_flag & P_WEXIT)
|
|
error = ESRCH;
|
|
|
|
PROC_UNLOCK(p); /* pfind() returns a locked process */
|
|
|
|
if (error == 0)
|
|
error = pmc_detach_process(p, pm);
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Retrieve the MSR number associated with the counter
|
|
* 'pmc_id'. This allows processes to directly use RDPMC
|
|
* instructions to read their PMCs, without the overhead of a
|
|
* system call.
|
|
*/
|
|
|
|
case PMC_OP_PMCGETMSR:
|
|
{
|
|
int ri;
|
|
struct pmc *pm;
|
|
struct pmc_target *pt;
|
|
struct pmc_op_getmsr gm;
|
|
|
|
PMC_DOWNGRADE_SX();
|
|
|
|
/* CPU has no 'GETMSR' support */
|
|
if (md->pmd_get_msr == NULL) {
|
|
error = ENOSYS;
|
|
break;
|
|
}
|
|
|
|
if ((error = copyin(arg, &gm, sizeof(gm))) != 0)
|
|
break;
|
|
|
|
if ((error = pmc_find_pmc(gm.pm_pmcid, &pm)) != 0)
|
|
break;
|
|
|
|
/*
|
|
* The allocated PMC has to be a process virtual PMC,
|
|
* i.e., of type MODE_T[CS]. Global PMCs can only be
|
|
* read using the PMCREAD operation since they may be
|
|
* allocated on a different CPU than the one we could
|
|
* be running on at the time of the RDPMC instruction.
|
|
*
|
|
* The GETMSR operation is not allowed for PMCs that
|
|
* are inherited across processes.
|
|
*/
|
|
|
|
if (!PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)) ||
|
|
(pm->pm_flags & PMC_F_DESCENDANTS)) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* It only makes sense to use a RDPMC (or its
|
|
* equivalent instruction on non-x86 architectures) on
|
|
* a process that has allocated and attached a PMC to
|
|
* itself. Conversely the PMC is only allowed to have
|
|
* one process attached to it -- its owner.
|
|
*/
|
|
|
|
if ((pt = LIST_FIRST(&pm->pm_targets)) == NULL ||
|
|
LIST_NEXT(pt, pt_next) != NULL ||
|
|
pt->pt_process->pp_proc != pm->pm_owner->po_owner) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
if ((error = (*md->pmd_get_msr)(ri, &gm.pm_msr)) < 0)
|
|
break;
|
|
|
|
if ((error = copyout(&gm, arg, sizeof(gm))) < 0)
|
|
break;
|
|
|
|
/*
|
|
* Mark our process as using MSRs. Update machine
|
|
* state using a forced context switch.
|
|
*/
|
|
|
|
pt->pt_process->pp_flags |= PMC_PP_ENABLE_MSR_ACCESS;
|
|
pmc_force_context_switch();
|
|
|
|
}
|
|
break;
|
|
|
|
/*
|
|
* Release an allocated PMC
|
|
*/
|
|
|
|
case PMC_OP_PMCRELEASE:
|
|
{
|
|
pmc_id_t pmcid;
|
|
struct pmc *pm;
|
|
struct pmc_owner *po;
|
|
struct pmc_op_simple sp;
|
|
|
|
/*
|
|
* Find PMC pointer for the named PMC.
|
|
*
|
|
* Use pmc_release_pmc_descriptor() to switch off the
|
|
* PMC, remove all its target threads, and remove the
|
|
* PMC from its owner's list.
|
|
*
|
|
* Remove the owner record if this is the last PMC
|
|
* owned.
|
|
*
|
|
* Free up space.
|
|
*/
|
|
|
|
if ((error = copyin(arg, &sp, sizeof(sp))) != 0)
|
|
break;
|
|
|
|
pmcid = sp.pm_pmcid;
|
|
|
|
if ((error = pmc_find_pmc(pmcid, &pm)) != 0)
|
|
break;
|
|
|
|
po = pm->pm_owner;
|
|
pmc_release_pmc_descriptor(pm);
|
|
pmc_maybe_remove_owner(po);
|
|
|
|
free(pm, M_PMC);
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Read and/or write a PMC.
|
|
*/
|
|
|
|
case PMC_OP_PMCRW:
|
|
{
|
|
uint32_t cpu, ri;
|
|
struct pmc *pm;
|
|
struct pmc_op_pmcrw *pprw;
|
|
struct pmc_op_pmcrw prw;
|
|
struct pmc_binding pb;
|
|
pmc_value_t oldvalue;
|
|
|
|
PMC_DOWNGRADE_SX();
|
|
|
|
if ((error = copyin(arg, &prw, sizeof(prw))) != 0)
|
|
break;
|
|
|
|
ri = 0;
|
|
PMCDBG(PMC,OPS,1, "rw id=%d flags=0x%x", prw.pm_pmcid,
|
|
prw.pm_flags);
|
|
|
|
/* must have at least one flag set */
|
|
if ((prw.pm_flags & (PMC_F_OLDVALUE|PMC_F_NEWVALUE)) == 0) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* locate pmc descriptor */
|
|
if ((error = pmc_find_pmc(prw.pm_pmcid, &pm)) != 0)
|
|
break;
|
|
|
|
/* Can't read a PMC that hasn't been started. */
|
|
if (pm->pm_state != PMC_STATE_ALLOCATED &&
|
|
pm->pm_state != PMC_STATE_STOPPED &&
|
|
pm->pm_state != PMC_STATE_RUNNING) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* writing a new value is allowed only for 'STOPPED' pmcs */
|
|
if (pm->pm_state == PMC_STATE_RUNNING &&
|
|
(prw.pm_flags & PMC_F_NEWVALUE)) {
|
|
error = EBUSY;
|
|
break;
|
|
}
|
|
|
|
if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) {
|
|
|
|
/*
|
|
* If this PMC is attached to its owner (i.e.,
|
|
* the process requesting this operation) and
|
|
* is running, then attempt to get an
|
|
* upto-date reading from hardware for a READ.
|
|
* Writes are only allowed when the PMC is
|
|
* stopped, so only update the saved value
|
|
* field.
|
|
*
|
|
* If the PMC is not running, or is not
|
|
* attached to its owner, read/write to the
|
|
* savedvalue field.
|
|
*/
|
|
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
mtx_pool_lock_spin(pmc_mtxpool, pm);
|
|
cpu = curthread->td_oncpu;
|
|
|
|
if (prw.pm_flags & PMC_F_OLDVALUE) {
|
|
if ((pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) &&
|
|
(pm->pm_state == PMC_STATE_RUNNING))
|
|
error = (*md->pmd_read_pmc)(cpu, ri,
|
|
&oldvalue);
|
|
else
|
|
oldvalue = pm->pm_gv.pm_savedvalue;
|
|
}
|
|
if (prw.pm_flags & PMC_F_NEWVALUE)
|
|
pm->pm_gv.pm_savedvalue = prw.pm_value;
|
|
|
|
mtx_pool_unlock_spin(pmc_mtxpool, pm);
|
|
|
|
} else { /* System mode PMCs */
|
|
cpu = PMC_TO_CPU(pm);
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
|
|
if (!pmc_cpu_is_active(cpu)) {
|
|
error = ENXIO;
|
|
break;
|
|
}
|
|
|
|
/* move this thread to CPU 'cpu' */
|
|
pmc_save_cpu_binding(&pb);
|
|
pmc_select_cpu(cpu);
|
|
|
|
critical_enter();
|
|
/* save old value */
|
|
if (prw.pm_flags & PMC_F_OLDVALUE)
|
|
if ((error = (*md->pmd_read_pmc)(cpu, ri,
|
|
&oldvalue)))
|
|
goto error;
|
|
/* write out new value */
|
|
if (prw.pm_flags & PMC_F_NEWVALUE)
|
|
error = (*md->pmd_write_pmc)(cpu, ri,
|
|
prw.pm_value);
|
|
error:
|
|
critical_exit();
|
|
pmc_restore_cpu_binding(&pb);
|
|
if (error)
|
|
break;
|
|
}
|
|
|
|
pprw = (struct pmc_op_pmcrw *) arg;
|
|
|
|
#ifdef DEBUG
|
|
if (prw.pm_flags & PMC_F_NEWVALUE)
|
|
PMCDBG(PMC,OPS,2, "rw id=%d new %jx -> old %jx",
|
|
ri, prw.pm_value, oldvalue);
|
|
else if (prw.pm_flags & PMC_F_OLDVALUE)
|
|
PMCDBG(PMC,OPS,2, "rw id=%d -> old %jx", ri, oldvalue);
|
|
#endif
|
|
|
|
/* return old value if requested */
|
|
if (prw.pm_flags & PMC_F_OLDVALUE)
|
|
if ((error = copyout(&oldvalue, &pprw->pm_value,
|
|
sizeof(prw.pm_value))))
|
|
break;
|
|
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Set the sampling rate for a sampling mode PMC and the
|
|
* initial count for a counting mode PMC.
|
|
*/
|
|
|
|
case PMC_OP_PMCSETCOUNT:
|
|
{
|
|
struct pmc *pm;
|
|
struct pmc_op_pmcsetcount sc;
|
|
|
|
PMC_DOWNGRADE_SX();
|
|
|
|
if ((error = copyin(arg, &sc, sizeof(sc))) != 0)
|
|
break;
|
|
|
|
if ((error = pmc_find_pmc(sc.pm_pmcid, &pm)) != 0)
|
|
break;
|
|
|
|
if (pm->pm_state == PMC_STATE_RUNNING) {
|
|
error = EBUSY;
|
|
break;
|
|
}
|
|
|
|
if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
|
|
pm->pm_sc.pm_reloadcount = sc.pm_count;
|
|
else
|
|
pm->pm_sc.pm_initial = sc.pm_count;
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Start a PMC.
|
|
*/
|
|
|
|
case PMC_OP_PMCSTART:
|
|
{
|
|
pmc_id_t pmcid;
|
|
struct pmc *pm;
|
|
struct pmc_op_simple sp;
|
|
|
|
sx_assert(&pmc_sx, SX_XLOCKED);
|
|
|
|
if ((error = copyin(arg, &sp, sizeof(sp))) != 0)
|
|
break;
|
|
|
|
pmcid = sp.pm_pmcid;
|
|
|
|
if ((error = pmc_find_pmc(pmcid, &pm)) != 0)
|
|
break;
|
|
|
|
KASSERT(pmcid == pm->pm_id,
|
|
("[pmc,%d] pmcid %x != id %x", __LINE__,
|
|
pm->pm_id, pmcid));
|
|
|
|
if (pm->pm_state == PMC_STATE_RUNNING) /* already running */
|
|
break;
|
|
else if (pm->pm_state != PMC_STATE_STOPPED &&
|
|
pm->pm_state != PMC_STATE_ALLOCATED) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
error = pmc_start(pm);
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Stop a PMC.
|
|
*/
|
|
|
|
case PMC_OP_PMCSTOP:
|
|
{
|
|
pmc_id_t pmcid;
|
|
struct pmc *pm;
|
|
struct pmc_op_simple sp;
|
|
|
|
PMC_DOWNGRADE_SX();
|
|
|
|
if ((error = copyin(arg, &sp, sizeof(sp))) != 0)
|
|
break;
|
|
|
|
pmcid = sp.pm_pmcid;
|
|
|
|
/*
|
|
* Mark the PMC as inactive and invoke the MD stop
|
|
* routines if needed.
|
|
*/
|
|
|
|
if ((error = pmc_find_pmc(pmcid, &pm)) != 0)
|
|
break;
|
|
|
|
KASSERT(pmcid == pm->pm_id,
|
|
("[pmc,%d] pmc id %x != pmcid %x", __LINE__,
|
|
pm->pm_id, pmcid));
|
|
|
|
if (pm->pm_state == PMC_STATE_STOPPED) /* already stopped */
|
|
break;
|
|
else if (pm->pm_state != PMC_STATE_RUNNING) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
error = pmc_stop(pm);
|
|
}
|
|
break;
|
|
|
|
|
|
/*
|
|
* Write a user supplied value to the log file.
|
|
*/
|
|
|
|
case PMC_OP_WRITELOG:
|
|
{
|
|
struct pmc_op_writelog wl;
|
|
struct pmc_owner *po;
|
|
|
|
PMC_DOWNGRADE_SX();
|
|
|
|
if ((error = copyin(arg, &wl, sizeof(wl))) != 0)
|
|
break;
|
|
|
|
if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) {
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
error = pmclog_process_userlog(po, &wl);
|
|
}
|
|
break;
|
|
|
|
|
|
default:
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (is_sx_downgraded)
|
|
sx_sunlock(&pmc_sx);
|
|
else
|
|
sx_xunlock(&pmc_sx);
|
|
|
|
if (error)
|
|
atomic_add_int(&pmc_stats.pm_syscall_errors, 1);
|
|
|
|
PICKUP_GIANT();
|
|
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Helper functions
|
|
*/
|
|
|
|
|
|
/*
|
|
* Mark the thread as needing callchain capture and post an AST. The
|
|
* actual callchain capture will be done in a context where it is safe
|
|
* to take page faults.
|
|
*/
|
|
|
|
static void
|
|
pmc_post_callchain_ast(void)
|
|
{
|
|
struct thread *td;
|
|
|
|
td = curthread;
|
|
|
|
/*
|
|
* Mark this thread as needing processing in ast().
|
|
* td->td_pflags will be safe to touch as the process was in
|
|
* user space when it was interrupted.
|
|
*/
|
|
td->td_pflags |= TDP_CALLCHAIN;
|
|
|
|
/*
|
|
* Again, since we've entered this function directly from
|
|
* userland, `td' is guaranteed to be not locked by this CPU,
|
|
* so its safe to try acquire the thread lock even though we
|
|
* are executing in an NMI context. We need to acquire this
|
|
* lock before touching `td_flags' because other CPUs may be
|
|
* in the process of touching this field.
|
|
*/
|
|
thread_lock(td);
|
|
td->td_flags |= TDF_ASTPENDING;
|
|
thread_unlock(td);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Interrupt processing.
|
|
*
|
|
* Find a free slot in the per-cpu array of samples and capture the
|
|
* current callchain there. If a sample was successfully added, a bit
|
|
* is set in mask 'pmc_cpumask' denoting that the DO_SAMPLES hook
|
|
* needs to be invoked from the clock handler.
|
|
*
|
|
* This function is meant to be called from an NMI handler. It cannot
|
|
* use any of the locking primitives supplied by the OS.
|
|
*/
|
|
|
|
int
|
|
pmc_process_interrupt(int cpu, struct pmc *pm, struct trapframe *tf,
|
|
int inuserspace)
|
|
{
|
|
int error, callchaindepth;
|
|
struct thread *td;
|
|
struct pmc_sample *ps;
|
|
struct pmc_samplebuffer *psb;
|
|
|
|
error = 0;
|
|
|
|
/*
|
|
* Allocate space for a sample buffer.
|
|
*/
|
|
psb = pmc_pcpu[cpu]->pc_sb;
|
|
|
|
ps = psb->ps_write;
|
|
if (ps->ps_nsamples) { /* in use, reader hasn't caught up */
|
|
pm->pm_stalled = 1;
|
|
atomic_add_int(&pmc_stats.pm_intr_bufferfull, 1);
|
|
PMCDBG(SAM,INT,1,"(spc) cpu=%d pm=%p tf=%p um=%d wr=%d rd=%d",
|
|
cpu, pm, (void *) tf, inuserspace,
|
|
(int) (psb->ps_write - psb->ps_samples),
|
|
(int) (psb->ps_read - psb->ps_samples));
|
|
error = ENOMEM;
|
|
goto done;
|
|
}
|
|
|
|
|
|
/* Fill in entry. */
|
|
PMCDBG(SAM,INT,1,"cpu=%d pm=%p tf=%p um=%d wr=%d rd=%d", cpu, pm,
|
|
(void *) tf, inuserspace,
|
|
(int) (psb->ps_write - psb->ps_samples),
|
|
(int) (psb->ps_read - psb->ps_samples));
|
|
|
|
atomic_add_rel_32(&pm->pm_runcount, 1); /* hold onto PMC */
|
|
ps->ps_pmc = pm;
|
|
if ((td = curthread) && td->td_proc)
|
|
ps->ps_pid = td->td_proc->p_pid;
|
|
else
|
|
ps->ps_pid = -1;
|
|
ps->ps_cpu = cpu;
|
|
ps->ps_flags = inuserspace ? PMC_CC_F_USERSPACE : 0;
|
|
|
|
callchaindepth = (pm->pm_flags & PMC_F_CALLCHAIN) ?
|
|
pmc_callchaindepth : 1;
|
|
|
|
if (callchaindepth == 1)
|
|
ps->ps_pc[0] = PMC_TRAPFRAME_TO_PC(tf);
|
|
else {
|
|
/*
|
|
* Kernel stack traversals can be done immediately,
|
|
* while we defer to an AST for user space traversals.
|
|
*/
|
|
if (!inuserspace)
|
|
callchaindepth =
|
|
pmc_save_kernel_callchain(ps->ps_pc,
|
|
callchaindepth, tf);
|
|
else {
|
|
pmc_post_callchain_ast();
|
|
callchaindepth = PMC_SAMPLE_INUSE;
|
|
}
|
|
}
|
|
|
|
ps->ps_nsamples = callchaindepth; /* mark entry as in use */
|
|
|
|
/* increment write pointer, modulo ring buffer size */
|
|
ps++;
|
|
if (ps == psb->ps_fence)
|
|
psb->ps_write = psb->ps_samples;
|
|
else
|
|
psb->ps_write = ps;
|
|
|
|
done:
|
|
/* mark CPU as needing processing */
|
|
atomic_set_rel_int(&pmc_cpumask, (1 << cpu));
|
|
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Capture a user call chain. This function will be called from ast()
|
|
* before control returns to userland and before the process gets
|
|
* rescheduled.
|
|
*/
|
|
|
|
static void
|
|
pmc_capture_user_callchain(int cpu, struct trapframe *tf)
|
|
{
|
|
int i;
|
|
struct pmc *pm;
|
|
struct pmc_sample *ps;
|
|
struct pmc_samplebuffer *psb;
|
|
|
|
psb = pmc_pcpu[cpu]->pc_sb;
|
|
|
|
/*
|
|
* Iterate through all deferred callchain requests.
|
|
*/
|
|
|
|
for (i = 0; i < pmc_nsamples; i++) {
|
|
|
|
ps = &psb->ps_samples[i];
|
|
if (ps->ps_nsamples != PMC_SAMPLE_INUSE)
|
|
continue;
|
|
|
|
pm = ps->ps_pmc;
|
|
|
|
KASSERT(pm->pm_flags & PMC_F_CALLCHAIN,
|
|
("[pmc,%d] Retrieving callchain for PMC that doesn't "
|
|
"want it", __LINE__));
|
|
|
|
/*
|
|
* Retrieve the callchain and mark the sample buffer
|
|
* as 'processable' by the timer tick sweep code.
|
|
*/
|
|
ps->ps_nsamples = pmc_save_user_callchain(ps->ps_pc,
|
|
pmc_callchaindepth, tf);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
/*
|
|
* Process saved PC samples.
|
|
*/
|
|
|
|
static void
|
|
pmc_process_samples(int cpu)
|
|
{
|
|
int n, ri;
|
|
struct pmc *pm;
|
|
struct thread *td;
|
|
struct pmc_owner *po;
|
|
struct pmc_sample *ps;
|
|
struct pmc_samplebuffer *psb;
|
|
|
|
KASSERT(PCPU_GET(cpuid) == cpu,
|
|
("[pmc,%d] not on the correct CPU pcpu=%d cpu=%d", __LINE__,
|
|
PCPU_GET(cpuid), cpu));
|
|
|
|
psb = pmc_pcpu[cpu]->pc_sb;
|
|
|
|
for (n = 0; n < pmc_nsamples; n++) { /* bound on #iterations */
|
|
|
|
ps = psb->ps_read;
|
|
if (ps->ps_nsamples == PMC_SAMPLE_FREE)
|
|
break;
|
|
if (ps->ps_nsamples == PMC_SAMPLE_INUSE) {
|
|
/* Need a rescan at a later time. */
|
|
atomic_set_rel_int(&pmc_cpumask, (1 << cpu));
|
|
break;
|
|
}
|
|
|
|
pm = ps->ps_pmc;
|
|
po = pm->pm_owner;
|
|
|
|
KASSERT(PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)),
|
|
("[pmc,%d] pmc=%p non-sampling mode=%d", __LINE__,
|
|
pm, PMC_TO_MODE(pm)));
|
|
|
|
/* Ignore PMCs that have been switched off */
|
|
if (pm->pm_state != PMC_STATE_RUNNING)
|
|
goto entrydone;
|
|
|
|
PMCDBG(SAM,OPS,1,"cpu=%d pm=%p n=%d fl=%x wr=%d rd=%d", cpu,
|
|
pm, ps->ps_nsamples, ps->ps_flags,
|
|
(int) (psb->ps_write - psb->ps_samples),
|
|
(int) (psb->ps_read - psb->ps_samples));
|
|
|
|
/*
|
|
* If this is a process-mode PMC that is attached to
|
|
* its owner, and if the PC is in user mode, update
|
|
* profiling statistics like timer-based profiling
|
|
* would have done.
|
|
*/
|
|
if (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) {
|
|
if (ps->ps_flags & PMC_CC_F_USERSPACE) {
|
|
td = FIRST_THREAD_IN_PROC(po->po_owner);
|
|
addupc_intr(td, ps->ps_pc[0], 1);
|
|
}
|
|
goto entrydone;
|
|
}
|
|
|
|
/*
|
|
* Otherwise, this is either a sampling mode PMC that
|
|
* is attached to a different process than its owner,
|
|
* or a system-wide sampling PMC. Dispatch a log
|
|
* entry to the PMC's owner process.
|
|
*/
|
|
|
|
pmclog_process_callchain(pm, ps);
|
|
|
|
entrydone:
|
|
ps->ps_nsamples = 0; /* mark entry as free */
|
|
atomic_subtract_rel_32(&pm->pm_runcount, 1);
|
|
|
|
/* increment read pointer, modulo sample size */
|
|
if (++ps == psb->ps_fence)
|
|
psb->ps_read = psb->ps_samples;
|
|
else
|
|
psb->ps_read = ps;
|
|
}
|
|
|
|
atomic_add_int(&pmc_stats.pm_log_sweeps, 1);
|
|
|
|
/* Do not re-enable stalled PMCs if we failed to process any samples */
|
|
if (n == 0)
|
|
return;
|
|
|
|
/*
|
|
* Restart any stalled sampling PMCs on this CPU.
|
|
*
|
|
* If the NMI handler sets the pm_stalled field of a PMC after
|
|
* the check below, we'll end up processing the stalled PMC at
|
|
* the next hardclock tick.
|
|
*/
|
|
for (n = 0; n < md->pmd_npmc; n++) {
|
|
(void) (*md->pmd_get_config)(cpu,n,&pm);
|
|
if (pm == NULL || /* !cfg'ed */
|
|
pm->pm_state != PMC_STATE_RUNNING || /* !active */
|
|
!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)) || /* !sampling */
|
|
pm->pm_stalled == 0) /* !stalled */
|
|
continue;
|
|
|
|
pm->pm_stalled = 0;
|
|
ri = PMC_TO_ROWINDEX(pm);
|
|
(*md->pmd_start_pmc)(cpu, ri);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Event handlers.
|
|
*/
|
|
|
|
/*
|
|
* Handle a process exit.
|
|
*
|
|
* Remove this process from all hash tables. If this process
|
|
* owned any PMCs, turn off those PMCs and deallocate them,
|
|
* removing any associations with target processes.
|
|
*
|
|
* This function will be called by the last 'thread' of a
|
|
* process.
|
|
*
|
|
* XXX This eventhandler gets called early in the exit process.
|
|
* Consider using a 'hook' invocation from thread_exit() or equivalent
|
|
* spot. Another negative is that kse_exit doesn't seem to call
|
|
* exit1() [??].
|
|
*
|
|
*/
|
|
|
|
static void
|
|
pmc_process_exit(void *arg __unused, struct proc *p)
|
|
{
|
|
int is_using_hwpmcs;
|
|
int cpu;
|
|
unsigned int ri;
|
|
struct pmc *pm;
|
|
struct pmc_process *pp;
|
|
struct pmc_owner *po;
|
|
pmc_value_t newvalue, tmp;
|
|
|
|
PROC_LOCK(p);
|
|
is_using_hwpmcs = p->p_flag & P_HWPMC;
|
|
PROC_UNLOCK(p);
|
|
|
|
/*
|
|
* Log a sysexit event to all SS PMC owners.
|
|
*/
|
|
LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_sysexit(po, p->p_pid);
|
|
|
|
if (!is_using_hwpmcs)
|
|
return;
|
|
|
|
PMC_GET_SX_XLOCK();
|
|
PMCDBG(PRC,EXT,1,"process-exit proc=%p (%d, %s)", p, p->p_pid,
|
|
p->p_comm);
|
|
|
|
/*
|
|
* Since this code is invoked by the last thread in an exiting
|
|
* process, we would have context switched IN at some prior
|
|
* point. However, with PREEMPTION, kernel mode context
|
|
* switches may happen any time, so we want to disable a
|
|
* context switch OUT till we get any PMCs targetting this
|
|
* process off the hardware.
|
|
*
|
|
* We also need to atomically remove this process'
|
|
* entry from our target process hash table, using
|
|
* PMC_FLAG_REMOVE.
|
|
*/
|
|
PMCDBG(PRC,EXT,1, "process-exit proc=%p (%d, %s)", p, p->p_pid,
|
|
p->p_comm);
|
|
|
|
critical_enter(); /* no preemption */
|
|
|
|
cpu = curthread->td_oncpu;
|
|
|
|
if ((pp = pmc_find_process_descriptor(p,
|
|
PMC_FLAG_REMOVE)) != NULL) {
|
|
|
|
PMCDBG(PRC,EXT,2,
|
|
"process-exit proc=%p pmc-process=%p", p, pp);
|
|
|
|
/*
|
|
* The exiting process could the target of
|
|
* some PMCs which will be running on
|
|
* currently executing CPU.
|
|
*
|
|
* We need to turn these PMCs off like we
|
|
* would do at context switch OUT time.
|
|
*/
|
|
for (ri = 0; ri < md->pmd_npmc; ri++) {
|
|
|
|
/*
|
|
* Pick up the pmc pointer from hardware
|
|
* state similar to the CSW_OUT code.
|
|
*/
|
|
pm = NULL;
|
|
(void) (*md->pmd_get_config)(cpu, ri, &pm);
|
|
|
|
PMCDBG(PRC,EXT,2, "ri=%d pm=%p", ri, pm);
|
|
|
|
if (pm == NULL ||
|
|
!PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)))
|
|
continue;
|
|
|
|
PMCDBG(PRC,EXT,2, "ppmcs[%d]=%p pm=%p "
|
|
"state=%d", ri, pp->pp_pmcs[ri].pp_pmc,
|
|
pm, pm->pm_state);
|
|
|
|
KASSERT(PMC_TO_ROWINDEX(pm) == ri,
|
|
("[pmc,%d] ri mismatch pmc(%d) ri(%d)",
|
|
__LINE__, PMC_TO_ROWINDEX(pm), ri));
|
|
|
|
KASSERT(pm == pp->pp_pmcs[ri].pp_pmc,
|
|
("[pmc,%d] pm %p != pp_pmcs[%d] %p",
|
|
__LINE__, pm, ri, pp->pp_pmcs[ri].pp_pmc));
|
|
|
|
(void) md->pmd_stop_pmc(cpu, ri);
|
|
|
|
KASSERT(pm->pm_runcount > 0,
|
|
("[pmc,%d] bad runcount ri %d rc %d",
|
|
__LINE__, ri, pm->pm_runcount));
|
|
|
|
/* Stop hardware only if it is actually running */
|
|
if (pm->pm_state == PMC_STATE_RUNNING &&
|
|
pm->pm_stalled == 0) {
|
|
md->pmd_read_pmc(cpu, ri, &newvalue);
|
|
tmp = newvalue -
|
|
PMC_PCPU_SAVED(cpu,ri);
|
|
|
|
mtx_pool_lock_spin(pmc_mtxpool, pm);
|
|
pm->pm_gv.pm_savedvalue += tmp;
|
|
pp->pp_pmcs[ri].pp_pmcval += tmp;
|
|
mtx_pool_unlock_spin(pmc_mtxpool, pm);
|
|
}
|
|
|
|
atomic_subtract_rel_32(&pm->pm_runcount,1);
|
|
|
|
KASSERT((int) pm->pm_runcount >= 0,
|
|
("[pmc,%d] runcount is %d", __LINE__, ri));
|
|
|
|
(void) md->pmd_config_pmc(cpu, ri, NULL);
|
|
}
|
|
|
|
/*
|
|
* Inform the MD layer of this pseudo "context switch
|
|
* out"
|
|
*/
|
|
(void) md->pmd_switch_out(pmc_pcpu[cpu], pp);
|
|
|
|
critical_exit(); /* ok to be pre-empted now */
|
|
|
|
/*
|
|
* Unlink this process from the PMCs that are
|
|
* targetting it. This will send a signal to
|
|
* all PMC owner's whose PMCs are orphaned.
|
|
*
|
|
* Log PMC value at exit time if requested.
|
|
*/
|
|
for (ri = 0; ri < md->pmd_npmc; ri++)
|
|
if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) {
|
|
if (pm->pm_flags & PMC_F_NEEDS_LOGFILE &&
|
|
PMC_IS_COUNTING_MODE(PMC_TO_MODE(pm)))
|
|
pmclog_process_procexit(pm, pp);
|
|
pmc_unlink_target_process(pm, pp);
|
|
}
|
|
free(pp, M_PMC);
|
|
|
|
} else
|
|
critical_exit(); /* pp == NULL */
|
|
|
|
|
|
/*
|
|
* If the process owned PMCs, free them up and free up
|
|
* memory.
|
|
*/
|
|
if ((po = pmc_find_owner_descriptor(p)) != NULL) {
|
|
pmc_remove_owner(po);
|
|
pmc_destroy_owner_descriptor(po);
|
|
}
|
|
|
|
sx_xunlock(&pmc_sx);
|
|
}
|
|
|
|
/*
|
|
* Handle a process fork.
|
|
*
|
|
* If the parent process 'p1' is under HWPMC monitoring, then copy
|
|
* over any attached PMCs that have 'do_descendants' semantics.
|
|
*/
|
|
|
|
static void
|
|
pmc_process_fork(void *arg __unused, struct proc *p1, struct proc *newproc,
|
|
int flags)
|
|
{
|
|
int is_using_hwpmcs;
|
|
unsigned int ri;
|
|
uint32_t do_descendants;
|
|
struct pmc *pm;
|
|
struct pmc_owner *po;
|
|
struct pmc_process *ppnew, *ppold;
|
|
|
|
(void) flags; /* unused parameter */
|
|
|
|
PROC_LOCK(p1);
|
|
is_using_hwpmcs = p1->p_flag & P_HWPMC;
|
|
PROC_UNLOCK(p1);
|
|
|
|
/*
|
|
* If there are system-wide sampling PMCs active, we need to
|
|
* log all fork events to their owner's logs.
|
|
*/
|
|
|
|
LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
|
|
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_procfork(po, p1->p_pid, newproc->p_pid);
|
|
|
|
if (!is_using_hwpmcs)
|
|
return;
|
|
|
|
PMC_GET_SX_XLOCK();
|
|
PMCDBG(PMC,FRK,1, "process-fork proc=%p (%d, %s) -> %p", p1,
|
|
p1->p_pid, p1->p_comm, newproc);
|
|
|
|
/*
|
|
* If the parent process (curthread->td_proc) is a
|
|
* target of any PMCs, look for PMCs that are to be
|
|
* inherited, and link these into the new process
|
|
* descriptor.
|
|
*/
|
|
if ((ppold = pmc_find_process_descriptor(curthread->td_proc,
|
|
PMC_FLAG_NONE)) == NULL)
|
|
goto done; /* nothing to do */
|
|
|
|
do_descendants = 0;
|
|
for (ri = 0; ri < md->pmd_npmc; ri++)
|
|
if ((pm = ppold->pp_pmcs[ri].pp_pmc) != NULL)
|
|
do_descendants |= pm->pm_flags & PMC_F_DESCENDANTS;
|
|
if (do_descendants == 0) /* nothing to do */
|
|
goto done;
|
|
|
|
/* allocate a descriptor for the new process */
|
|
if ((ppnew = pmc_find_process_descriptor(newproc,
|
|
PMC_FLAG_ALLOCATE)) == NULL)
|
|
goto done;
|
|
|
|
/*
|
|
* Run through all PMCs that were targeting the old process
|
|
* and which specified F_DESCENDANTS and attach them to the
|
|
* new process.
|
|
*
|
|
* Log the fork event to all owners of PMCs attached to this
|
|
* process, if not already logged.
|
|
*/
|
|
for (ri = 0; ri < md->pmd_npmc; ri++)
|
|
if ((pm = ppold->pp_pmcs[ri].pp_pmc) != NULL &&
|
|
(pm->pm_flags & PMC_F_DESCENDANTS)) {
|
|
pmc_link_target_process(pm, ppnew);
|
|
po = pm->pm_owner;
|
|
if (po->po_sscount == 0 &&
|
|
po->po_flags & PMC_PO_OWNS_LOGFILE)
|
|
pmclog_process_procfork(po, p1->p_pid,
|
|
newproc->p_pid);
|
|
}
|
|
|
|
/*
|
|
* Now mark the new process as being tracked by this driver.
|
|
*/
|
|
PROC_LOCK(newproc);
|
|
newproc->p_flag |= P_HWPMC;
|
|
PROC_UNLOCK(newproc);
|
|
|
|
done:
|
|
sx_xunlock(&pmc_sx);
|
|
}
|
|
|
|
|
|
/*
|
|
* initialization
|
|
*/
|
|
|
|
static const char *pmc_name_of_pmcclass[] = {
|
|
#undef __PMC_CLASS
|
|
#define __PMC_CLASS(N) #N ,
|
|
__PMC_CLASSES()
|
|
};
|
|
|
|
static int
|
|
pmc_initialize(void)
|
|
{
|
|
int cpu, error, n;
|
|
unsigned int maxcpu;
|
|
struct pmc_binding pb;
|
|
struct pmc_sample *ps;
|
|
struct pmc_samplebuffer *sb;
|
|
|
|
md = NULL;
|
|
error = 0;
|
|
|
|
#ifdef DEBUG
|
|
/* parse debug flags first */
|
|
if (TUNABLE_STR_FETCH(PMC_SYSCTL_NAME_PREFIX "debugflags",
|
|
pmc_debugstr, sizeof(pmc_debugstr)))
|
|
pmc_debugflags_parse(pmc_debugstr,
|
|
pmc_debugstr+strlen(pmc_debugstr));
|
|
#endif
|
|
|
|
PMCDBG(MOD,INI,0, "PMC Initialize (version %x)", PMC_VERSION);
|
|
|
|
/* check kernel version */
|
|
if (pmc_kernel_version != PMC_VERSION) {
|
|
if (pmc_kernel_version == 0)
|
|
printf("hwpmc: this kernel has not been compiled with "
|
|
"'options HWPMC_HOOKS'.\n");
|
|
else
|
|
printf("hwpmc: kernel version (0x%x) does not match "
|
|
"module version (0x%x).\n", pmc_kernel_version,
|
|
PMC_VERSION);
|
|
return EPROGMISMATCH;
|
|
}
|
|
|
|
/*
|
|
* check sysctl parameters
|
|
*/
|
|
|
|
if (pmc_hashsize <= 0) {
|
|
(void) printf("hwpmc: tunable \"hashsize\"=%d must be "
|
|
"greater than zero.\n", pmc_hashsize);
|
|
pmc_hashsize = PMC_HASH_SIZE;
|
|
}
|
|
|
|
if (pmc_nsamples <= 0 || pmc_nsamples > 65535) {
|
|
(void) printf("hwpmc: tunable \"nsamples\"=%d out of "
|
|
"range.\n", pmc_nsamples);
|
|
pmc_nsamples = PMC_NSAMPLES;
|
|
}
|
|
|
|
if (pmc_callchaindepth <= 0 ||
|
|
pmc_callchaindepth > PMC_CALLCHAIN_DEPTH_MAX) {
|
|
(void) printf("hwpmc: tunable \"callchaindepth\"=%d out of "
|
|
"range.\n", pmc_callchaindepth);
|
|
pmc_callchaindepth = PMC_CALLCHAIN_DEPTH;
|
|
}
|
|
|
|
md = pmc_md_initialize();
|
|
|
|
if (md == NULL || md->pmd_init == NULL)
|
|
return ENOSYS;
|
|
|
|
maxcpu = pmc_cpu_max();
|
|
|
|
/* allocate space for the per-cpu array */
|
|
pmc_pcpu = malloc(maxcpu * sizeof(struct pmc_cpu *),
|
|
M_PMC, M_WAITOK|M_ZERO);
|
|
|
|
/* per-cpu 'saved values' for managing process-mode PMCs */
|
|
pmc_pcpu_saved = malloc(sizeof(pmc_value_t) * maxcpu * md->pmd_npmc,
|
|
M_PMC, M_WAITOK);
|
|
|
|
/* Perform CPU-dependent initialization. */
|
|
pmc_save_cpu_binding(&pb);
|
|
for (cpu = 0; cpu < maxcpu; cpu++) {
|
|
if (!pmc_cpu_is_active(cpu))
|
|
continue;
|
|
pmc_select_cpu(cpu);
|
|
if ((error = md->pmd_init(cpu)) != 0)
|
|
break;
|
|
}
|
|
pmc_restore_cpu_binding(&pb);
|
|
|
|
if (error != 0)
|
|
return error;
|
|
|
|
/* allocate space for the sample array */
|
|
for (cpu = 0; cpu < maxcpu; cpu++) {
|
|
if (!pmc_cpu_is_active(cpu))
|
|
continue;
|
|
sb = malloc(sizeof(struct pmc_samplebuffer) +
|
|
pmc_nsamples * sizeof(struct pmc_sample), M_PMC,
|
|
M_WAITOK|M_ZERO);
|
|
|
|
sb->ps_read = sb->ps_write = sb->ps_samples;
|
|
sb->ps_fence = sb->ps_samples + pmc_nsamples;
|
|
KASSERT(pmc_pcpu[cpu] != NULL,
|
|
("[pmc,%d] cpu=%d Null per-cpu data", __LINE__, cpu));
|
|
|
|
sb->ps_callchains = malloc(pmc_callchaindepth *
|
|
pmc_nsamples * sizeof(uintptr_t),
|
|
M_PMC, M_WAITOK|M_ZERO);
|
|
|
|
for (n = 0, ps = sb->ps_samples; n < pmc_nsamples; n++, ps++)
|
|
ps->ps_pc = sb->ps_callchains +
|
|
(n * pmc_callchaindepth);
|
|
|
|
pmc_pcpu[cpu]->pc_sb = sb;
|
|
}
|
|
|
|
/* allocate space for the row disposition array */
|
|
pmc_pmcdisp = malloc(sizeof(enum pmc_mode) * md->pmd_npmc,
|
|
M_PMC, M_WAITOK|M_ZERO);
|
|
|
|
KASSERT(pmc_pmcdisp != NULL,
|
|
("[pmc,%d] pmcdisp allocation returned NULL", __LINE__));
|
|
|
|
/* mark all PMCs as available */
|
|
for (n = 0; n < (int) md->pmd_npmc; n++)
|
|
PMC_MARK_ROW_FREE(n);
|
|
|
|
/* allocate thread hash tables */
|
|
pmc_ownerhash = hashinit(pmc_hashsize, M_PMC,
|
|
&pmc_ownerhashmask);
|
|
|
|
pmc_processhash = hashinit(pmc_hashsize, M_PMC,
|
|
&pmc_processhashmask);
|
|
mtx_init(&pmc_processhash_mtx, "pmc-process-hash", "pmc-leaf",
|
|
MTX_SPIN);
|
|
|
|
LIST_INIT(&pmc_ss_owners);
|
|
pmc_ss_count = 0;
|
|
|
|
/* allocate a pool of spin mutexes */
|
|
pmc_mtxpool = mtx_pool_create("pmc-leaf", pmc_mtxpool_size,
|
|
MTX_SPIN);
|
|
|
|
PMCDBG(MOD,INI,1, "pmc_ownerhash=%p, mask=0x%lx "
|
|
"targethash=%p mask=0x%lx", pmc_ownerhash, pmc_ownerhashmask,
|
|
pmc_processhash, pmc_processhashmask);
|
|
|
|
/* register process {exit,fork,exec} handlers */
|
|
pmc_exit_tag = EVENTHANDLER_REGISTER(process_exit,
|
|
pmc_process_exit, NULL, EVENTHANDLER_PRI_ANY);
|
|
pmc_fork_tag = EVENTHANDLER_REGISTER(process_fork,
|
|
pmc_process_fork, NULL, EVENTHANDLER_PRI_ANY);
|
|
|
|
/* initialize logging */
|
|
pmclog_initialize();
|
|
|
|
/* set hook functions */
|
|
pmc_intr = md->pmd_intr;
|
|
pmc_hook = pmc_hook_handler;
|
|
|
|
if (error == 0) {
|
|
printf(PMC_MODULE_NAME ":");
|
|
for (n = 0; n < (int) md->pmd_nclass; n++) {
|
|
printf(" %s/%d/0x%b",
|
|
pmc_name_of_pmcclass[md->pmd_classes[n].pm_class],
|
|
md->pmd_nclasspmcs[n],
|
|
md->pmd_classes[n].pm_caps,
|
|
"\20"
|
|
"\1INT\2USR\3SYS\4EDG\5THR"
|
|
"\6REA\7WRI\10INV\11QUA\12PRC"
|
|
"\13TAG\14CSC");
|
|
}
|
|
printf("\n");
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
/* prepare to be unloaded */
|
|
static void
|
|
pmc_cleanup(void)
|
|
{
|
|
int cpu;
|
|
unsigned int maxcpu;
|
|
struct pmc_ownerhash *ph;
|
|
struct pmc_owner *po, *tmp;
|
|
struct pmc_binding pb;
|
|
#ifdef DEBUG
|
|
struct pmc_processhash *prh;
|
|
#endif
|
|
|
|
PMCDBG(MOD,INI,0, "%s", "cleanup");
|
|
|
|
/* switch off sampling */
|
|
atomic_store_rel_int(&pmc_cpumask, 0);
|
|
pmc_intr = NULL;
|
|
|
|
sx_xlock(&pmc_sx);
|
|
if (pmc_hook == NULL) { /* being unloaded already */
|
|
sx_xunlock(&pmc_sx);
|
|
return;
|
|
}
|
|
|
|
pmc_hook = NULL; /* prevent new threads from entering module */
|
|
|
|
/* deregister event handlers */
|
|
EVENTHANDLER_DEREGISTER(process_fork, pmc_fork_tag);
|
|
EVENTHANDLER_DEREGISTER(process_exit, pmc_exit_tag);
|
|
|
|
/* send SIGBUS to all owner threads, free up allocations */
|
|
if (pmc_ownerhash)
|
|
for (ph = pmc_ownerhash;
|
|
ph <= &pmc_ownerhash[pmc_ownerhashmask];
|
|
ph++) {
|
|
LIST_FOREACH_SAFE(po, ph, po_next, tmp) {
|
|
pmc_remove_owner(po);
|
|
|
|
/* send SIGBUS to owner processes */
|
|
PMCDBG(MOD,INI,2, "cleanup signal proc=%p "
|
|
"(%d, %s)", po->po_owner,
|
|
po->po_owner->p_pid,
|
|
po->po_owner->p_comm);
|
|
|
|
PROC_LOCK(po->po_owner);
|
|
psignal(po->po_owner, SIGBUS);
|
|
PROC_UNLOCK(po->po_owner);
|
|
|
|
pmc_destroy_owner_descriptor(po);
|
|
}
|
|
}
|
|
|
|
/* reclaim allocated data structures */
|
|
if (pmc_mtxpool)
|
|
mtx_pool_destroy(&pmc_mtxpool);
|
|
|
|
mtx_destroy(&pmc_processhash_mtx);
|
|
if (pmc_processhash) {
|
|
#ifdef DEBUG
|
|
struct pmc_process *pp;
|
|
|
|
PMCDBG(MOD,INI,3, "%s", "destroy process hash");
|
|
for (prh = pmc_processhash;
|
|
prh <= &pmc_processhash[pmc_processhashmask];
|
|
prh++)
|
|
LIST_FOREACH(pp, prh, pp_next)
|
|
PMCDBG(MOD,INI,3, "pid=%d", pp->pp_proc->p_pid);
|
|
#endif
|
|
|
|
hashdestroy(pmc_processhash, M_PMC, pmc_processhashmask);
|
|
pmc_processhash = NULL;
|
|
}
|
|
|
|
if (pmc_ownerhash) {
|
|
PMCDBG(MOD,INI,3, "%s", "destroy owner hash");
|
|
hashdestroy(pmc_ownerhash, M_PMC, pmc_ownerhashmask);
|
|
pmc_ownerhash = NULL;
|
|
}
|
|
|
|
KASSERT(LIST_EMPTY(&pmc_ss_owners),
|
|
("[pmc,%d] Global SS owner list not empty", __LINE__));
|
|
KASSERT(pmc_ss_count == 0,
|
|
("[pmc,%d] Global SS count not empty", __LINE__));
|
|
|
|
/* Free the per-cpu sample buffers. */
|
|
maxcpu = pmc_cpu_max();
|
|
for (cpu = 0; cpu < maxcpu; cpu++) {
|
|
if (!pmc_cpu_is_active(cpu))
|
|
continue;
|
|
KASSERT(pmc_pcpu[cpu]->pc_sb != NULL,
|
|
("[pmc,%d] Null cpu sample buffer cpu=%d", __LINE__,
|
|
cpu));
|
|
free(pmc_pcpu[cpu]->pc_sb->ps_callchains, M_PMC);
|
|
free(pmc_pcpu[cpu]->pc_sb, M_PMC);
|
|
pmc_pcpu[cpu]->pc_sb = NULL;
|
|
}
|
|
|
|
/* do processor dependent cleanup */
|
|
PMCDBG(MOD,INI,3, "%s", "md cleanup");
|
|
if (md) {
|
|
pmc_save_cpu_binding(&pb);
|
|
for (cpu = 0; cpu < maxcpu; cpu++) {
|
|
PMCDBG(MOD,INI,1,"pmc-cleanup cpu=%d pcs=%p",
|
|
cpu, pmc_pcpu[cpu]);
|
|
if (!pmc_cpu_is_active(cpu) || pmc_pcpu[cpu] == NULL)
|
|
continue;
|
|
pmc_select_cpu(cpu);
|
|
if (md->pmd_cleanup)
|
|
md->pmd_cleanup(cpu);
|
|
}
|
|
free(md, M_PMC);
|
|
md = NULL;
|
|
pmc_restore_cpu_binding(&pb);
|
|
}
|
|
|
|
/* deallocate per-cpu structures */
|
|
free(pmc_pcpu, M_PMC);
|
|
pmc_pcpu = NULL;
|
|
|
|
free(pmc_pcpu_saved, M_PMC);
|
|
pmc_pcpu_saved = NULL;
|
|
|
|
if (pmc_pmcdisp) {
|
|
free(pmc_pmcdisp, M_PMC);
|
|
pmc_pmcdisp = NULL;
|
|
}
|
|
|
|
pmclog_shutdown();
|
|
|
|
sx_xunlock(&pmc_sx); /* we are done */
|
|
}
|
|
|
|
/*
|
|
* The function called at load/unload.
|
|
*/
|
|
|
|
static int
|
|
load (struct module *module __unused, int cmd, void *arg __unused)
|
|
{
|
|
int error;
|
|
|
|
error = 0;
|
|
|
|
switch (cmd) {
|
|
case MOD_LOAD :
|
|
/* initialize the subsystem */
|
|
error = pmc_initialize();
|
|
if (error != 0)
|
|
break;
|
|
PMCDBG(MOD,INI,1, "syscall=%d maxcpu=%d",
|
|
pmc_syscall_num, pmc_cpu_max());
|
|
break;
|
|
|
|
|
|
case MOD_UNLOAD :
|
|
case MOD_SHUTDOWN:
|
|
pmc_cleanup();
|
|
PMCDBG(MOD,INI,1, "%s", "unloaded");
|
|
break;
|
|
|
|
default :
|
|
error = EINVAL; /* XXX should panic(9) */
|
|
break;
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
/* memory pool */
|
|
MALLOC_DEFINE(M_PMC, "pmc", "Memory space for the PMC module");
|