345 lines
8.2 KiB
C
345 lines
8.2 KiB
C
/*-
|
|
* Copyright (c) 2003-2008 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 AUTHORS 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 AUTHORS 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.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "opt_hwpmc_hooks.h"
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/ctype.h>
|
|
#include <sys/param.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/pmc.h>
|
|
#include <sys/pmckern.h>
|
|
#include <sys/smp.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/systm.h>
|
|
|
|
#ifdef HWPMC_HOOKS
|
|
FEATURE(hwpmc_hooks, "Kernel support for HW PMC");
|
|
#define PMC_KERNEL_VERSION PMC_VERSION
|
|
#else
|
|
#define PMC_KERNEL_VERSION 0
|
|
#endif
|
|
|
|
MALLOC_DECLARE(M_PMCHOOKS);
|
|
MALLOC_DEFINE(M_PMCHOOKS, "pmchooks", "Memory space for PMC hooks");
|
|
|
|
const int pmc_kernel_version = PMC_KERNEL_VERSION;
|
|
|
|
/* Hook variable. */
|
|
int __read_mostly (*pmc_hook)(struct thread *td, int function, void *arg) = NULL;
|
|
|
|
/* Interrupt handler */
|
|
int __read_mostly (*pmc_intr)(int cpu, struct trapframe *tf) = NULL;
|
|
|
|
/* Bitmask of CPUs requiring servicing at hardclock time */
|
|
volatile cpuset_t pmc_cpumask;
|
|
|
|
/*
|
|
* A global count of SS mode PMCs. When non-zero, this means that
|
|
* we have processes that are sampling the system as a whole.
|
|
*/
|
|
volatile int pmc_ss_count;
|
|
|
|
/*
|
|
* Since PMC(4) may not be loaded in the current kernel, the
|
|
* convention followed is that a non-NULL value of 'pmc_hook' implies
|
|
* the presence of this kernel module.
|
|
*
|
|
* This requires us to protect 'pmc_hook' with a
|
|
* shared (sx) lock -- thus making the process of calling into PMC(4)
|
|
* somewhat more expensive than a simple 'if' check and indirect call.
|
|
*/
|
|
struct sx pmc_sx;
|
|
|
|
/*
|
|
* PMC Soft per cpu trapframe.
|
|
*/
|
|
struct trapframe pmc_tf[MAXCPU];
|
|
|
|
/*
|
|
* PMC Soft use a global table to store registered events.
|
|
*/
|
|
|
|
SYSCTL_NODE(_kern, OID_AUTO, hwpmc, CTLFLAG_RW, 0, "HWPMC parameters");
|
|
|
|
static int pmc_softevents = 16;
|
|
SYSCTL_INT(_kern_hwpmc, OID_AUTO, softevents, CTLFLAG_RDTUN,
|
|
&pmc_softevents, 0, "maximum number of soft events");
|
|
|
|
struct mtx pmc_softs_mtx;
|
|
int pmc_softs_count;
|
|
struct pmc_soft **pmc_softs;
|
|
|
|
MTX_SYSINIT(pmc_soft_mtx, &pmc_softs_mtx, "pmc-softs", MTX_SPIN);
|
|
|
|
static void
|
|
pmc_init_sx(void)
|
|
{
|
|
sx_init_flags(&pmc_sx, "pmc-sx", SX_NOWITNESS);
|
|
}
|
|
|
|
SYSINIT(pmcsx, SI_SUB_LOCK, SI_ORDER_MIDDLE, pmc_init_sx, NULL);
|
|
|
|
/*
|
|
* Helper functions.
|
|
*/
|
|
|
|
/*
|
|
* A note on the CPU numbering scheme used by the hwpmc(4) driver.
|
|
*
|
|
* CPUs are denoted using numbers in the range 0..[pmc_cpu_max()-1].
|
|
* CPUs could be numbered "sparsely" in this range; the predicate
|
|
* `pmc_cpu_is_present()' is used to test whether a given CPU is
|
|
* physically present.
|
|
*
|
|
* Further, a CPU that is physically present may be administratively
|
|
* disabled or otherwise unavailable for use by hwpmc(4). The
|
|
* `pmc_cpu_is_active()' predicate tests for CPU usability. An
|
|
* "active" CPU participates in thread scheduling and can field
|
|
* interrupts raised by PMC hardware.
|
|
*
|
|
* On systems with hyperthreaded CPUs, multiple logical CPUs may share
|
|
* PMC hardware resources. For such processors one logical CPU is
|
|
* denoted as the primary owner of the in-CPU PMC resources. The
|
|
* pmc_cpu_is_primary() predicate is used to distinguish this primary
|
|
* CPU from the others.
|
|
*/
|
|
|
|
int
|
|
pmc_cpu_is_active(int cpu)
|
|
{
|
|
#ifdef SMP
|
|
return (pmc_cpu_is_present(cpu) &&
|
|
!CPU_ISSET(cpu, &hlt_cpus_mask));
|
|
#else
|
|
return (1);
|
|
#endif
|
|
}
|
|
|
|
/* Deprecated. */
|
|
int
|
|
pmc_cpu_is_disabled(int cpu)
|
|
{
|
|
return (!pmc_cpu_is_active(cpu));
|
|
}
|
|
|
|
int
|
|
pmc_cpu_is_present(int cpu)
|
|
{
|
|
#ifdef SMP
|
|
return (!CPU_ABSENT(cpu));
|
|
#else
|
|
return (1);
|
|
#endif
|
|
}
|
|
|
|
int
|
|
pmc_cpu_is_primary(int cpu)
|
|
{
|
|
#ifdef SMP
|
|
return (!CPU_ISSET(cpu, &logical_cpus_mask));
|
|
#else
|
|
return (1);
|
|
#endif
|
|
}
|
|
|
|
|
|
/*
|
|
* Return the maximum CPU number supported by the system. The return
|
|
* value is used for scaling internal data structures and for runtime
|
|
* checks.
|
|
*/
|
|
unsigned int
|
|
pmc_cpu_max(void)
|
|
{
|
|
#ifdef SMP
|
|
return (mp_maxid+1);
|
|
#else
|
|
return (1);
|
|
#endif
|
|
}
|
|
|
|
#ifdef INVARIANTS
|
|
|
|
/*
|
|
* Return the count of CPUs in the `active' state in the system.
|
|
*/
|
|
int
|
|
pmc_cpu_max_active(void)
|
|
{
|
|
#ifdef SMP
|
|
/*
|
|
* When support for CPU hot-plugging is added to the kernel,
|
|
* this function would change to return the current number
|
|
* of "active" CPUs.
|
|
*/
|
|
return (mp_ncpus);
|
|
#else
|
|
return (1);
|
|
#endif
|
|
}
|
|
|
|
#endif
|
|
|
|
/*
|
|
* Cleanup event name:
|
|
* - remove duplicate '_'
|
|
* - all uppercase
|
|
*/
|
|
static void
|
|
pmc_soft_namecleanup(char *name)
|
|
{
|
|
char *p, *q;
|
|
|
|
p = q = name;
|
|
|
|
for ( ; *p == '_' ; p++)
|
|
;
|
|
for ( ; *p ; p++) {
|
|
if (*p == '_' && (*(p + 1) == '_' || *(p + 1) == '\0'))
|
|
continue;
|
|
else
|
|
*q++ = toupper(*p);
|
|
}
|
|
*q = '\0';
|
|
}
|
|
|
|
void
|
|
pmc_soft_ev_register(struct pmc_soft *ps)
|
|
{
|
|
static int warned = 0;
|
|
int n;
|
|
|
|
ps->ps_running = 0;
|
|
ps->ps_ev.pm_ev_code = 0; /* invalid */
|
|
pmc_soft_namecleanup(ps->ps_ev.pm_ev_name);
|
|
|
|
mtx_lock_spin(&pmc_softs_mtx);
|
|
|
|
if (pmc_softs_count >= pmc_softevents) {
|
|
/*
|
|
* XXX Reusing events can enter a race condition where
|
|
* new allocated event will be used as an old one.
|
|
*/
|
|
for (n = 0; n < pmc_softevents; n++)
|
|
if (pmc_softs[n] == NULL)
|
|
break;
|
|
if (n == pmc_softevents) {
|
|
mtx_unlock_spin(&pmc_softs_mtx);
|
|
if (!warned) {
|
|
printf("hwpmc: too many soft events, "
|
|
"increase kern.hwpmc.softevents tunable\n");
|
|
warned = 1;
|
|
}
|
|
return;
|
|
}
|
|
|
|
ps->ps_ev.pm_ev_code = PMC_EV_SOFT_FIRST + n;
|
|
pmc_softs[n] = ps;
|
|
} else {
|
|
ps->ps_ev.pm_ev_code = PMC_EV_SOFT_FIRST + pmc_softs_count;
|
|
pmc_softs[pmc_softs_count++] = ps;
|
|
}
|
|
|
|
mtx_unlock_spin(&pmc_softs_mtx);
|
|
}
|
|
|
|
void
|
|
pmc_soft_ev_deregister(struct pmc_soft *ps)
|
|
{
|
|
|
|
KASSERT(ps != NULL, ("pmc_soft_deregister: called with NULL"));
|
|
|
|
mtx_lock_spin(&pmc_softs_mtx);
|
|
|
|
if (ps->ps_ev.pm_ev_code != 0 &&
|
|
(ps->ps_ev.pm_ev_code - PMC_EV_SOFT_FIRST) < pmc_softevents) {
|
|
KASSERT((int)ps->ps_ev.pm_ev_code >= PMC_EV_SOFT_FIRST &&
|
|
(int)ps->ps_ev.pm_ev_code <= PMC_EV_SOFT_LAST,
|
|
("pmc_soft_deregister: invalid event value"));
|
|
pmc_softs[ps->ps_ev.pm_ev_code - PMC_EV_SOFT_FIRST] = NULL;
|
|
}
|
|
|
|
mtx_unlock_spin(&pmc_softs_mtx);
|
|
}
|
|
|
|
struct pmc_soft *
|
|
pmc_soft_ev_acquire(enum pmc_event ev)
|
|
{
|
|
struct pmc_soft *ps;
|
|
|
|
if (ev == 0 || (ev - PMC_EV_SOFT_FIRST) >= pmc_softevents)
|
|
return NULL;
|
|
|
|
KASSERT((int)ev >= PMC_EV_SOFT_FIRST &&
|
|
(int)ev <= PMC_EV_SOFT_LAST,
|
|
("event out of range"));
|
|
|
|
mtx_lock_spin(&pmc_softs_mtx);
|
|
|
|
ps = pmc_softs[ev - PMC_EV_SOFT_FIRST];
|
|
if (ps == NULL)
|
|
mtx_unlock_spin(&pmc_softs_mtx);
|
|
|
|
return ps;
|
|
}
|
|
|
|
void
|
|
pmc_soft_ev_release(struct pmc_soft *ps)
|
|
{
|
|
|
|
mtx_unlock_spin(&pmc_softs_mtx);
|
|
}
|
|
|
|
/*
|
|
* Initialise hwpmc.
|
|
*/
|
|
static void
|
|
init_hwpmc(void *dummy __unused)
|
|
{
|
|
if (pmc_softevents <= 0 ||
|
|
pmc_softevents > PMC_EV_DYN_COUNT) {
|
|
(void) printf("hwpmc: tunable \"softevents\"=%d out of "
|
|
"range.\n", pmc_softevents);
|
|
pmc_softevents = PMC_EV_DYN_COUNT;
|
|
}
|
|
pmc_softs = malloc(pmc_softevents * sizeof(struct pmc_soft *), M_PMCHOOKS, M_NOWAIT|M_ZERO);
|
|
KASSERT(pmc_softs != NULL, ("cannot allocate soft events table"));
|
|
}
|
|
|
|
SYSINIT(hwpmc, SI_SUB_KDTRACE, SI_ORDER_FIRST, init_hwpmc, NULL);
|
|
|