freebsd-skq/sys/dev/hwpmc/hwpmc_logging.c
rwatson 4af919b491 Second-to-last commit implementing Capsicum capabilities in the FreeBSD
kernel for FreeBSD 9.0:

Add a new capability mask argument to fget(9) and friends, allowing system
call code to declare what capabilities are required when an integer file
descriptor is converted into an in-kernel struct file *.  With options
CAPABILITIES compiled into the kernel, this enforces capability
protection; without, this change is effectively a no-op.

Some cases require special handling, such as mmap(2), which must preserve
information about the maximum rights at the time of mapping in the memory
map so that they can later be enforced in mprotect(2) -- this is done by
narrowing the rights in the existing max_protection field used for similar
purposes with file permissions.

In namei(9), we assert that the code is not reached from within capability
mode, as we're not yet ready to enforce namespace capabilities there.
This will follow in a later commit.

Update two capability names: CAP_EVENT and CAP_KEVENT become
CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they
represent.

Approved by:	re (bz)
Submitted by:	jonathan
Sponsored by:	Google Inc
2011-08-11 12:30:23 +00:00

1026 lines
25 KiB
C

/*-
* Copyright (c) 2005-2007 Joseph Koshy
* Copyright (c) 2007 The FreeBSD Foundation
* All rights reserved.
*
* Portions of this software were developed by A. Joseph Koshy under
* sponsorship from the FreeBSD Foundation and Google, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/*
* Logging code for hwpmc(4)
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/capability.h>
#include <sys/file.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/pmc.h>
#include <sys/pmckern.h>
#include <sys/pmclog.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/unistd.h>
#include <sys/vnode.h>
/*
* Sysctl tunables
*/
SYSCTL_DECL(_kern_hwpmc);
/*
* kern.hwpmc.logbuffersize -- size of the per-cpu owner buffers.
*/
static int pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "logbuffersize", &pmclog_buffer_size);
SYSCTL_INT(_kern_hwpmc, OID_AUTO, logbuffersize, CTLFLAG_TUN|CTLFLAG_RD,
&pmclog_buffer_size, 0, "size of log buffers in kilobytes");
/*
* kern.hwpmc.nbuffer -- number of global log buffers
*/
static int pmc_nlogbuffers = PMC_NLOGBUFFERS;
TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "nbuffers", &pmc_nlogbuffers);
SYSCTL_INT(_kern_hwpmc, OID_AUTO, nbuffers, CTLFLAG_TUN|CTLFLAG_RD,
&pmc_nlogbuffers, 0, "number of global log buffers");
/*
* Global log buffer list and associated spin lock.
*/
TAILQ_HEAD(, pmclog_buffer) pmc_bufferlist =
TAILQ_HEAD_INITIALIZER(pmc_bufferlist);
static struct mtx pmc_bufferlist_mtx; /* spin lock */
static struct mtx pmc_kthread_mtx; /* sleep lock */
#define PMCLOG_INIT_BUFFER_DESCRIPTOR(D) do { \
const int __roundup = roundup(sizeof(*D), \
sizeof(uint32_t)); \
(D)->plb_fence = ((char *) (D)) + \
1024*pmclog_buffer_size; \
(D)->plb_base = (D)->plb_ptr = ((char *) (D)) + \
__roundup; \
} while (0)
/*
* Log file record constructors.
*/
#define _PMCLOG_TO_HEADER(T,L) \
((PMCLOG_HEADER_MAGIC << 24) | \
(PMCLOG_TYPE_ ## T << 16) | \
((L) & 0xFFFF))
/* reserve LEN bytes of space and initialize the entry header */
#define _PMCLOG_RESERVE(PO,TYPE,LEN,ACTION) do { \
uint32_t *_le; \
int _len = roundup((LEN), sizeof(uint32_t)); \
if ((_le = pmclog_reserve((PO), _len)) == NULL) { \
ACTION; \
} \
*_le = _PMCLOG_TO_HEADER(TYPE,_len); \
_le += 3 /* skip over timestamp */
#define PMCLOG_RESERVE(P,T,L) _PMCLOG_RESERVE(P,T,L,return)
#define PMCLOG_RESERVE_WITH_ERROR(P,T,L) _PMCLOG_RESERVE(P,T,L, \
error=ENOMEM;goto error)
#define PMCLOG_EMIT32(V) do { *_le++ = (V); } while (0)
#define PMCLOG_EMIT64(V) do { \
*_le++ = (uint32_t) ((V) & 0xFFFFFFFF); \
*_le++ = (uint32_t) (((V) >> 32) & 0xFFFFFFFF); \
} while (0)
/* Emit a string. Caution: does NOT update _le, so needs to be last */
#define PMCLOG_EMITSTRING(S,L) do { bcopy((S), _le, (L)); } while (0)
#define PMCLOG_DESPATCH(PO) \
pmclog_release((PO)); \
} while (0)
/*
* Assertions about the log file format.
*/
CTASSERT(sizeof(struct pmclog_callchain) == 6*4 +
PMC_CALLCHAIN_DEPTH_MAX*sizeof(uintfptr_t));
CTASSERT(sizeof(struct pmclog_closelog) == 3*4);
CTASSERT(sizeof(struct pmclog_dropnotify) == 3*4);
CTASSERT(sizeof(struct pmclog_map_in) == PATH_MAX +
4*4 + sizeof(uintfptr_t));
CTASSERT(offsetof(struct pmclog_map_in,pl_pathname) ==
4*4 + sizeof(uintfptr_t));
CTASSERT(sizeof(struct pmclog_map_out) == 4*4 + 2*sizeof(uintfptr_t));
CTASSERT(sizeof(struct pmclog_pcsample) == 6*4 + sizeof(uintfptr_t));
CTASSERT(sizeof(struct pmclog_pmcallocate) == 6*4);
CTASSERT(sizeof(struct pmclog_pmcattach) == 5*4 + PATH_MAX);
CTASSERT(offsetof(struct pmclog_pmcattach,pl_pathname) == 5*4);
CTASSERT(sizeof(struct pmclog_pmcdetach) == 5*4);
CTASSERT(sizeof(struct pmclog_proccsw) == 5*4 + 8);
CTASSERT(sizeof(struct pmclog_procexec) == 5*4 + PATH_MAX +
sizeof(uintfptr_t));
CTASSERT(offsetof(struct pmclog_procexec,pl_pathname) == 5*4 +
sizeof(uintfptr_t));
CTASSERT(sizeof(struct pmclog_procexit) == 5*4 + 8);
CTASSERT(sizeof(struct pmclog_procfork) == 5*4);
CTASSERT(sizeof(struct pmclog_sysexit) == 4*4);
CTASSERT(sizeof(struct pmclog_userdata) == 4*4);
/*
* Log buffer structure
*/
struct pmclog_buffer {
TAILQ_ENTRY(pmclog_buffer) plb_next;
char *plb_base;
char *plb_ptr;
char *plb_fence;
};
/*
* Prototypes
*/
static int pmclog_get_buffer(struct pmc_owner *po);
static void pmclog_loop(void *arg);
static void pmclog_release(struct pmc_owner *po);
static uint32_t *pmclog_reserve(struct pmc_owner *po, int length);
static void pmclog_schedule_io(struct pmc_owner *po);
static void pmclog_stop_kthread(struct pmc_owner *po);
/*
* Helper functions
*/
/*
* Get a log buffer
*/
static int
pmclog_get_buffer(struct pmc_owner *po)
{
struct pmclog_buffer *plb;
mtx_assert(&po->po_mtx, MA_OWNED);
KASSERT(po->po_curbuf == NULL,
("[pmclog,%d] po=%p current buffer still valid", __LINE__, po));
mtx_lock_spin(&pmc_bufferlist_mtx);
if ((plb = TAILQ_FIRST(&pmc_bufferlist)) != NULL)
TAILQ_REMOVE(&pmc_bufferlist, plb, plb_next);
mtx_unlock_spin(&pmc_bufferlist_mtx);
PMCDBG(LOG,GTB,1, "po=%p plb=%p", po, plb);
#ifdef DEBUG
if (plb)
KASSERT(plb->plb_ptr == plb->plb_base &&
plb->plb_base < plb->plb_fence,
("[pmclog,%d] po=%p buffer invariants: ptr=%p "
"base=%p fence=%p", __LINE__, po, plb->plb_ptr,
plb->plb_base, plb->plb_fence));
#endif
po->po_curbuf = plb;
/* update stats */
atomic_add_int(&pmc_stats.pm_buffer_requests, 1);
if (plb == NULL)
atomic_add_int(&pmc_stats.pm_buffer_requests_failed, 1);
return (plb ? 0 : ENOMEM);
}
/*
* Log handler loop.
*
* This function is executed by each pmc owner's helper thread.
*/
static void
pmclog_loop(void *arg)
{
int error, last_buffer;
struct pmc_owner *po;
struct pmclog_buffer *lb;
struct proc *p;
struct ucred *ownercred;
struct ucred *mycred;
struct thread *td;
struct uio auio;
struct iovec aiov;
size_t nbytes;
po = (struct pmc_owner *) arg;
p = po->po_owner;
td = curthread;
mycred = td->td_ucred;
last_buffer = 0;
PROC_LOCK(p);
ownercred = crhold(p->p_ucred);
PROC_UNLOCK(p);
PMCDBG(LOG,INI,1, "po=%p kt=%p", po, po->po_kthread);
KASSERT(po->po_kthread == curthread->td_proc,
("[pmclog,%d] proc mismatch po=%p po/kt=%p curproc=%p", __LINE__,
po, po->po_kthread, curthread->td_proc));
lb = NULL;
/*
* Loop waiting for I/O requests to be added to the owner
* struct's queue. The loop is exited when the log file
* is deconfigured.
*/
mtx_lock(&pmc_kthread_mtx);
for (;;) {
/* check if we've been asked to exit */
if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
break;
if (lb == NULL) { /* look for a fresh buffer to write */
mtx_lock_spin(&po->po_mtx);
if ((lb = TAILQ_FIRST(&po->po_logbuffers)) == NULL) {
mtx_unlock_spin(&po->po_mtx);
(void) msleep(po, &pmc_kthread_mtx, PWAIT,
"pmcloop", 0);
continue;
}
TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
if (po->po_flags & PMC_PO_SHUTDOWN)
last_buffer = TAILQ_EMPTY(&po->po_logbuffers);
mtx_unlock_spin(&po->po_mtx);
}
mtx_unlock(&pmc_kthread_mtx);
/* process the request */
PMCDBG(LOG,WRI,2, "po=%p base=%p ptr=%p", po,
lb->plb_base, lb->plb_ptr);
/* change our thread's credentials before issuing the I/O */
aiov.iov_base = lb->plb_base;
aiov.iov_len = nbytes = lb->plb_ptr - lb->plb_base;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = -1;
auio.uio_resid = nbytes;
auio.uio_rw = UIO_WRITE;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_td = td;
/* switch thread credentials -- see kern_ktrace.c */
td->td_ucred = ownercred;
error = fo_write(po->po_file, &auio, ownercred, 0, td);
td->td_ucred = mycred;
if (error) {
/* XXX some errors are recoverable */
/* send a SIGIO to the owner and exit */
PROC_LOCK(p);
psignal(p, SIGIO);
PROC_UNLOCK(p);
mtx_lock(&pmc_kthread_mtx);
po->po_error = error; /* save for flush log */
PMCDBG(LOG,WRI,2, "po=%p error=%d", po, error);
break;
}
if (last_buffer) {
/*
* Close the file to get PMCLOG_EOF error
* in pmclog(3).
*/
fo_close(po->po_file, curthread);
}
mtx_lock(&pmc_kthread_mtx);
/* put the used buffer back into the global pool */
PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
mtx_lock_spin(&pmc_bufferlist_mtx);
TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
mtx_unlock_spin(&pmc_bufferlist_mtx);
lb = NULL;
}
po->po_kthread = NULL;
mtx_unlock(&pmc_kthread_mtx);
/* return the current I/O buffer to the global pool */
if (lb) {
PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
mtx_lock_spin(&pmc_bufferlist_mtx);
TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
mtx_unlock_spin(&pmc_bufferlist_mtx);
}
/*
* Exit this thread, signalling the waiter
*/
crfree(ownercred);
kproc_exit(0);
}
/*
* Release and log entry and schedule an I/O if needed.
*/
static void
pmclog_release(struct pmc_owner *po)
{
KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base,
("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base));
KASSERT(po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_fence));
/* schedule an I/O if we've filled a buffer */
if (po->po_curbuf->plb_ptr >= po->po_curbuf->plb_fence)
pmclog_schedule_io(po);
mtx_unlock_spin(&po->po_mtx);
PMCDBG(LOG,REL,1, "po=%p", po);
}
/*
* Attempt to reserve 'length' bytes of space in an owner's log
* buffer. The function returns a pointer to 'length' bytes of space
* if there was enough space or returns NULL if no space was
* available. Non-null returns do so with the po mutex locked. The
* caller must invoke pmclog_release() on the pmc owner structure
* when done.
*/
static uint32_t *
pmclog_reserve(struct pmc_owner *po, int length)
{
uintptr_t newptr, oldptr;
uint32_t *lh;
struct timespec ts;
PMCDBG(LOG,ALL,1, "po=%p len=%d", po, length);
KASSERT(length % sizeof(uint32_t) == 0,
("[pmclog,%d] length not a multiple of word size", __LINE__));
mtx_lock_spin(&po->po_mtx);
/* No more data when shutdown in progress. */
if (po->po_flags & PMC_PO_SHUTDOWN) {
mtx_unlock_spin(&po->po_mtx);
return (NULL);
}
if (po->po_curbuf == NULL)
if (pmclog_get_buffer(po) != 0) {
mtx_unlock_spin(&po->po_mtx);
return (NULL);
}
KASSERT(po->po_curbuf != NULL,
("[pmclog,%d] po=%p no current buffer", __LINE__, po));
KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base &&
po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
__LINE__, po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base,
po->po_curbuf->plb_fence));
oldptr = (uintptr_t) po->po_curbuf->plb_ptr;
newptr = oldptr + length;
KASSERT(oldptr != (uintptr_t) NULL,
("[pmclog,%d] po=%p Null log buffer pointer", __LINE__, po));
/*
* If we have space in the current buffer, return a pointer to
* available space with the PO structure locked.
*/
if (newptr <= (uintptr_t) po->po_curbuf->plb_fence) {
po->po_curbuf->plb_ptr = (char *) newptr;
goto done;
}
/*
* Otherwise, schedule the current buffer for output and get a
* fresh buffer.
*/
pmclog_schedule_io(po);
if (pmclog_get_buffer(po) != 0) {
mtx_unlock_spin(&po->po_mtx);
return (NULL);
}
KASSERT(po->po_curbuf != NULL,
("[pmclog,%d] po=%p no current buffer", __LINE__, po));
KASSERT(po->po_curbuf->plb_ptr != NULL,
("[pmclog,%d] null return from pmc_get_log_buffer", __LINE__));
KASSERT(po->po_curbuf->plb_ptr == po->po_curbuf->plb_base &&
po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
__LINE__, po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base,
po->po_curbuf->plb_fence));
oldptr = (uintptr_t) po->po_curbuf->plb_ptr;
done:
lh = (uint32_t *) oldptr;
lh++; /* skip header */
getnanotime(&ts); /* fill in the timestamp */
*lh++ = ts.tv_sec & 0xFFFFFFFF;
*lh++ = ts.tv_nsec & 0xFFFFFFF;
return ((uint32_t *) oldptr);
}
/*
* Schedule an I/O.
*
* Transfer the current buffer to the helper kthread.
*/
static void
pmclog_schedule_io(struct pmc_owner *po)
{
KASSERT(po->po_curbuf != NULL,
("[pmclog,%d] schedule_io with null buffer po=%p", __LINE__, po));
KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base,
("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base));
KASSERT(po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_fence));
PMCDBG(LOG,SIO, 1, "po=%p", po);
mtx_assert(&po->po_mtx, MA_OWNED);
/*
* Add the current buffer to the tail of the buffer list and
* wakeup the helper.
*/
TAILQ_INSERT_TAIL(&po->po_logbuffers, po->po_curbuf, plb_next);
po->po_curbuf = NULL;
wakeup_one(po);
}
/*
* Stop the helper kthread.
*/
static void
pmclog_stop_kthread(struct pmc_owner *po)
{
/*
* Close the file to force the thread out of fo_write,
* unset flag, wakeup the helper thread,
* wait for it to exit
*/
if (po->po_file != NULL)
fo_close(po->po_file, curthread);
mtx_lock(&pmc_kthread_mtx);
po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
wakeup_one(po);
if (po->po_kthread)
msleep(po->po_kthread, &pmc_kthread_mtx, PPAUSE, "pmckstp", 0);
mtx_unlock(&pmc_kthread_mtx);
}
/*
* Public functions
*/
/*
* Configure a log file for pmc owner 'po'.
*
* Parameter 'logfd' is a file handle referencing an open file in the
* owner process. This file needs to have been opened for writing.
*/
int
pmclog_configure_log(struct pmc_mdep *md, struct pmc_owner *po, int logfd)
{
int error;
struct proc *p;
/*
* As long as it is possible to get a LOR between pmc_sx lock and
* proctree/allproc sx locks used for adding a new process, assure
* the former is not held here.
*/
sx_assert(&pmc_sx, SA_UNLOCKED);
PMCDBG(LOG,CFG,1, "config po=%p logfd=%d", po, logfd);
p = po->po_owner;
/* return EBUSY if a log file was already present */
if (po->po_flags & PMC_PO_OWNS_LOGFILE)
return (EBUSY);
KASSERT(po->po_kthread == NULL,
("[pmclog,%d] po=%p kthread (%p) already present", __LINE__, po,
po->po_kthread));
KASSERT(po->po_file == NULL,
("[pmclog,%d] po=%p file (%p) already present", __LINE__, po,
po->po_file));
/* get a reference to the file state */
error = fget_write(curthread, logfd, CAP_WRITE, &po->po_file);
if (error)
goto error;
/* mark process as owning a log file */
po->po_flags |= PMC_PO_OWNS_LOGFILE;
error = kproc_create(pmclog_loop, po, &po->po_kthread,
RFHIGHPID, 0, "hwpmc: proc(%d)", p->p_pid);
if (error)
goto error;
/* mark process as using HWPMCs */
PROC_LOCK(p);
p->p_flag |= P_HWPMC;
PROC_UNLOCK(p);
/* create a log initialization entry */
PMCLOG_RESERVE_WITH_ERROR(po, INITIALIZE,
sizeof(struct pmclog_initialize));
PMCLOG_EMIT32(PMC_VERSION);
PMCLOG_EMIT32(md->pmd_cputype);
PMCLOG_DESPATCH(po);
return (0);
error:
/* shutdown the thread */
if (po->po_kthread)
pmclog_stop_kthread(po);
KASSERT(po->po_kthread == NULL, ("[pmclog,%d] po=%p kthread not "
"stopped", __LINE__, po));
if (po->po_file)
(void) fdrop(po->po_file, curthread);
po->po_file = NULL; /* clear file and error state */
po->po_error = 0;
return (error);
}
/*
* De-configure a log file. This will throw away any buffers queued
* for this owner process.
*/
int
pmclog_deconfigure_log(struct pmc_owner *po)
{
int error;
struct pmclog_buffer *lb;
PMCDBG(LOG,CFG,1, "de-config po=%p", po);
if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
return (EINVAL);
KASSERT(po->po_sscount == 0,
("[pmclog,%d] po=%p still owning SS PMCs", __LINE__, po));
KASSERT(po->po_file != NULL,
("[pmclog,%d] po=%p no log file", __LINE__, po));
/* stop the kthread, this will reset the 'OWNS_LOGFILE' flag */
if (po->po_kthread)
pmclog_stop_kthread(po);
KASSERT(po->po_kthread == NULL,
("[pmclog,%d] po=%p kthread not stopped", __LINE__, po));
/* return all queued log buffers to the global pool */
while ((lb = TAILQ_FIRST(&po->po_logbuffers)) != NULL) {
TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
mtx_lock_spin(&pmc_bufferlist_mtx);
TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
mtx_unlock_spin(&pmc_bufferlist_mtx);
}
/* return the 'current' buffer to the global pool */
if ((lb = po->po_curbuf) != NULL) {
PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
mtx_lock_spin(&pmc_bufferlist_mtx);
TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
mtx_unlock_spin(&pmc_bufferlist_mtx);
}
/* drop a reference to the fd */
error = fdrop(po->po_file, curthread);
po->po_file = NULL;
po->po_error = 0;
return (error);
}
/*
* Flush a process' log buffer.
*/
int
pmclog_flush(struct pmc_owner *po)
{
int error;
PMCDBG(LOG,FLS,1, "po=%p", po);
/*
* If there is a pending error recorded by the logger thread,
* return that.
*/
if (po->po_error)
return (po->po_error);
error = 0;
/*
* Check that we do have an active log file.
*/
mtx_lock(&pmc_kthread_mtx);
if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) {
error = EINVAL;
goto error;
}
/*
* Schedule the current buffer if any.
*/
mtx_lock_spin(&po->po_mtx);
if (po->po_curbuf)
pmclog_schedule_io(po);
mtx_unlock_spin(&po->po_mtx);
/*
* Initiate shutdown: no new data queued,
* thread will close file on last block.
*/
po->po_flags |= PMC_PO_SHUTDOWN;
error:
mtx_unlock(&pmc_kthread_mtx);
return (error);
}
void
pmclog_process_callchain(struct pmc *pm, struct pmc_sample *ps)
{
int n, recordlen;
uint32_t flags;
struct pmc_owner *po;
PMCDBG(LOG,SAM,1,"pm=%p pid=%d n=%d", pm, ps->ps_pid,
ps->ps_nsamples);
recordlen = offsetof(struct pmclog_callchain, pl_pc) +
ps->ps_nsamples * sizeof(uintfptr_t);
po = pm->pm_owner;
flags = PMC_CALLCHAIN_TO_CPUFLAGS(ps->ps_cpu,ps->ps_flags);
PMCLOG_RESERVE(po, CALLCHAIN, recordlen);
PMCLOG_EMIT32(ps->ps_pid);
PMCLOG_EMIT32(pm->pm_id);
PMCLOG_EMIT32(flags);
for (n = 0; n < ps->ps_nsamples; n++)
PMCLOG_EMITADDR(ps->ps_pc[n]);
PMCLOG_DESPATCH(po);
}
void
pmclog_process_closelog(struct pmc_owner *po)
{
PMCLOG_RESERVE(po,CLOSELOG,sizeof(struct pmclog_closelog));
PMCLOG_DESPATCH(po);
}
void
pmclog_process_dropnotify(struct pmc_owner *po)
{
PMCLOG_RESERVE(po,DROPNOTIFY,sizeof(struct pmclog_dropnotify));
PMCLOG_DESPATCH(po);
}
void
pmclog_process_map_in(struct pmc_owner *po, pid_t pid, uintfptr_t start,
const char *path)
{
int pathlen, recordlen;
KASSERT(path != NULL, ("[pmclog,%d] map-in, null path", __LINE__));
pathlen = strlen(path) + 1; /* #bytes for path name */
recordlen = offsetof(struct pmclog_map_in, pl_pathname) +
pathlen;
PMCLOG_RESERVE(po, MAP_IN, recordlen);
PMCLOG_EMIT32(pid);
PMCLOG_EMITADDR(start);
PMCLOG_EMITSTRING(path,pathlen);
PMCLOG_DESPATCH(po);
}
void
pmclog_process_map_out(struct pmc_owner *po, pid_t pid, uintfptr_t start,
uintfptr_t end)
{
KASSERT(start <= end, ("[pmclog,%d] start > end", __LINE__));
PMCLOG_RESERVE(po, MAP_OUT, sizeof(struct pmclog_map_out));
PMCLOG_EMIT32(pid);
PMCLOG_EMITADDR(start);
PMCLOG_EMITADDR(end);
PMCLOG_DESPATCH(po);
}
void
pmclog_process_pmcallocate(struct pmc *pm)
{
struct pmc_owner *po;
po = pm->pm_owner;
PMCDBG(LOG,ALL,1, "pm=%p", pm);
PMCLOG_RESERVE(po, PMCALLOCATE, sizeof(struct pmclog_pmcallocate));
PMCLOG_EMIT32(pm->pm_id);
PMCLOG_EMIT32(pm->pm_event);
PMCLOG_EMIT32(pm->pm_flags);
PMCLOG_DESPATCH(po);
}
void
pmclog_process_pmcattach(struct pmc *pm, pid_t pid, char *path)
{
int pathlen, recordlen;
struct pmc_owner *po;
PMCDBG(LOG,ATT,1,"pm=%p pid=%d", pm, pid);
po = pm->pm_owner;
pathlen = strlen(path) + 1; /* #bytes for the string */
recordlen = offsetof(struct pmclog_pmcattach, pl_pathname) + pathlen;
PMCLOG_RESERVE(po, PMCATTACH, recordlen);
PMCLOG_EMIT32(pm->pm_id);
PMCLOG_EMIT32(pid);
PMCLOG_EMITSTRING(path, pathlen);
PMCLOG_DESPATCH(po);
}
void
pmclog_process_pmcdetach(struct pmc *pm, pid_t pid)
{
struct pmc_owner *po;
PMCDBG(LOG,ATT,1,"!pm=%p pid=%d", pm, pid);
po = pm->pm_owner;
PMCLOG_RESERVE(po, PMCDETACH, sizeof(struct pmclog_pmcdetach));
PMCLOG_EMIT32(pm->pm_id);
PMCLOG_EMIT32(pid);
PMCLOG_DESPATCH(po);
}
/*
* Log a context switch event to the log file.
*/
void
pmclog_process_proccsw(struct pmc *pm, struct pmc_process *pp, pmc_value_t v)
{
struct pmc_owner *po;
KASSERT(pm->pm_flags & PMC_F_LOG_PROCCSW,
("[pmclog,%d] log-process-csw called gratuitously", __LINE__));
PMCDBG(LOG,SWO,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
v);
po = pm->pm_owner;
PMCLOG_RESERVE(po, PROCCSW, sizeof(struct pmclog_proccsw));
PMCLOG_EMIT32(pm->pm_id);
PMCLOG_EMIT64(v);
PMCLOG_EMIT32(pp->pp_proc->p_pid);
PMCLOG_DESPATCH(po);
}
void
pmclog_process_procexec(struct pmc_owner *po, pmc_id_t pmid, pid_t pid,
uintfptr_t startaddr, char *path)
{
int pathlen, recordlen;
PMCDBG(LOG,EXC,1,"po=%p pid=%d path=\"%s\"", po, pid, path);
pathlen = strlen(path) + 1; /* #bytes for the path */
recordlen = offsetof(struct pmclog_procexec, pl_pathname) + pathlen;
PMCLOG_RESERVE(po, PROCEXEC, recordlen);
PMCLOG_EMIT32(pid);
PMCLOG_EMITADDR(startaddr);
PMCLOG_EMIT32(pmid);
PMCLOG_EMITSTRING(path,pathlen);
PMCLOG_DESPATCH(po);
}
/*
* Log a process exit event (and accumulated pmc value) to the log file.
*/
void
pmclog_process_procexit(struct pmc *pm, struct pmc_process *pp)
{
int ri;
struct pmc_owner *po;
ri = PMC_TO_ROWINDEX(pm);
PMCDBG(LOG,EXT,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
pp->pp_pmcs[ri].pp_pmcval);
po = pm->pm_owner;
PMCLOG_RESERVE(po, PROCEXIT, sizeof(struct pmclog_procexit));
PMCLOG_EMIT32(pm->pm_id);
PMCLOG_EMIT64(pp->pp_pmcs[ri].pp_pmcval);
PMCLOG_EMIT32(pp->pp_proc->p_pid);
PMCLOG_DESPATCH(po);
}
/*
* Log a fork event.
*/
void
pmclog_process_procfork(struct pmc_owner *po, pid_t oldpid, pid_t newpid)
{
PMCLOG_RESERVE(po, PROCFORK, sizeof(struct pmclog_procfork));
PMCLOG_EMIT32(oldpid);
PMCLOG_EMIT32(newpid);
PMCLOG_DESPATCH(po);
}
/*
* Log a process exit event of the form suitable for system-wide PMCs.
*/
void
pmclog_process_sysexit(struct pmc_owner *po, pid_t pid)
{
PMCLOG_RESERVE(po, SYSEXIT, sizeof(struct pmclog_sysexit));
PMCLOG_EMIT32(pid);
PMCLOG_DESPATCH(po);
}
/*
* Write a user log entry.
*/
int
pmclog_process_userlog(struct pmc_owner *po, struct pmc_op_writelog *wl)
{
int error;
PMCDBG(LOG,WRI,1, "writelog po=%p ud=0x%x", po, wl->pm_userdata);
error = 0;
PMCLOG_RESERVE_WITH_ERROR(po, USERDATA,
sizeof(struct pmclog_userdata));
PMCLOG_EMIT32(wl->pm_userdata);
PMCLOG_DESPATCH(po);
error:
return (error);
}
/*
* Initialization.
*
* Create a pool of log buffers and initialize mutexes.
*/
void
pmclog_initialize()
{
int n;
struct pmclog_buffer *plb;
if (pmclog_buffer_size <= 0) {
(void) printf("hwpmc: tunable logbuffersize=%d must be "
"greater than zero.\n", pmclog_buffer_size);
pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
}
if (pmc_nlogbuffers <= 0) {
(void) printf("hwpmc: tunable nlogbuffers=%d must be greater "
"than zero.\n", pmc_nlogbuffers);
pmc_nlogbuffers = PMC_NLOGBUFFERS;
}
/* create global pool of log buffers */
for (n = 0; n < pmc_nlogbuffers; n++) {
plb = malloc(1024 * pmclog_buffer_size, M_PMC,
M_WAITOK|M_ZERO);
PMCLOG_INIT_BUFFER_DESCRIPTOR(plb);
TAILQ_INSERT_HEAD(&pmc_bufferlist, plb, plb_next);
}
mtx_init(&pmc_bufferlist_mtx, "pmc-buffer-list", "pmc-leaf",
MTX_SPIN);
mtx_init(&pmc_kthread_mtx, "pmc-kthread", "pmc-sleep", MTX_DEF);
}
/*
* Shutdown logging.
*
* Destroy mutexes and release memory back the to free pool.
*/
void
pmclog_shutdown()
{
struct pmclog_buffer *plb;
mtx_destroy(&pmc_kthread_mtx);
mtx_destroy(&pmc_bufferlist_mtx);
while ((plb = TAILQ_FIRST(&pmc_bufferlist)) != NULL) {
TAILQ_REMOVE(&pmc_bufferlist, plb, plb_next);
free(plb, M_PMC);
}
}