d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

- Re-implement lock profiling in such a way that it no longer breaks

Browse Source 
the ABI when enabled.  There is no longer an embedded lock_profile_object
   in each lock.  Instead a list of lock_profile_objects is kept per-thread
   for each lock it may own.  The cnt_hold statistic is now always 0 to
   facilitate this.
 - Support shared locking by tracking individual lock instances and
   statistics in the per-thread per-instance lock_profile_object.
 - Make the lock profiling hash table a per-cpu singly linked list with a
   per-cpu static lock_prof allocator.  This removes the need for an array
   of spinlocks and reduces cache contention between cores.
 - Use a seperate hash for spinlocks and other locks so that only a
   critical_enter() is required and not a spinlock_enter() to modify the
   per-cpu tables.
 - Count time spent spinning in the lock statistics.
 - Remove the LOCK_PROFILE_SHARED option as it is always supported now.
 - Specifically drop and release the scheduler locks in both schedulers
   since we track owners now.

In collaboration with:	Kip Macy
Sponsored by:	Nokia
This commit is contained in:
Jeff Roberson 2007-12-15 23:13:31 +00:00
parent 4c908c35e0
commit eea4f254fe
12 changed files with 506 additions and 439 deletions

1
sys/conf/options

@ -540,7 +540,6 @@ MUTEX_DEBUG opt_global.h
MUTEX_NOINLINE opt_global.h
LOCK_PROFILING opt_global.h
LOCK_PROFILING_FAST opt_global.h
LOCK_PROFILING_SHARED opt_global.h
MSIZE opt_global.h
REGRESSION opt_global.h
RESTARTABLE_PANICS opt_global.h

26
sys/kern/kern_mutex.c

@ -123,20 +123,6 @@ struct lock_class lock_class_mtx_spin = {
struct mtx blocked_lock;
struct mtx Giant;
#ifdef LOCK_PROFILING
static inline void lock_profile_init(void)
{
int i;
/* Initialize the mutex profiling locks */
for (i = 0; i < LPROF_LOCK_SIZE; i++) {
mtx_init(&lprof_locks[i], "mprof lock",
NULL, MTX_SPIN|MTX_QUIET|MTX_NOPROFILE);
}
}
#else
static inline void lock_profile_init(void) {;}
#endif
void
assert_mtx(struct lock_object *lock, int what)
{
@ -425,7 +411,7 @@ _mtx_lock_sleep(struct mtx *m, uintptr_t tid, int opts, const char *file,
}
#endif
lock_profile_obtain_lock_success(&m->lock_object, contested,
waittime, (file), (line));
waittime, file, line);
}
static void
@ -514,7 +500,8 @@ retry:
m->mtx_recurse++;
break;
}
lock_profile_obtain_lock_failed(&m->lock_object, &contested, &waittime);
lock_profile_obtain_lock_failed(&m->lock_object,
&contested, &waittime);
/* Give interrupts a chance while we spin. */
spinlock_exit();
while (m->mtx_lock != MTX_UNOWNED) {
@ -535,8 +522,9 @@ retry:
break;
_rel_spin_lock(m); /* does spinlock_exit() */
}
lock_profile_obtain_lock_success(&m->lock_object, contested,
waittime, (file), (line));
if (m->mtx_recurse == 0)
lock_profile_obtain_lock_success(&m->lock_object, contested,
waittime, (file), (line));
WITNESS_LOCK(&m->lock_object, opts | LOP_EXCLUSIVE, file, line);
}
@ -794,8 +782,6 @@ mutex_init(void)
mtx_init(&proc0.p_slock, "process slock", NULL, MTX_SPIN | MTX_RECURSE);
mtx_init(&devmtx, "cdev", NULL, MTX_DEF);
mtx_lock(&Giant);
lock_profile_init();
}
#ifdef DDB

31
sys/kern/kern_rwlock.c

@ -227,10 +227,8 @@ _rw_rlock(struct rwlock *rw, const char *file, int line)
#ifdef ADAPTIVE_RWLOCKS
volatile struct thread *owner;
#endif
#ifdef LOCK_PROFILING_SHARED
uint64_t waittime = 0;
int contested = 0;
#endif
uintptr_t x;
KASSERT(rw->rw_lock != RW_DESTROYED,
@ -273,12 +271,6 @@ _rw_rlock(struct rwlock *rw, const char *file, int line)
MPASS((x & RW_LOCK_READ_WAITERS) == 0);
if (atomic_cmpset_acq_ptr(&rw->rw_lock, x,
x + RW_ONE_READER)) {
#ifdef LOCK_PROFILING_SHARED
if (RW_READERS(x) == 0)
lock_profile_obtain_lock_success(
&rw->lock_object, contested,
waittime, file, line);
#endif
if (LOCK_LOG_TEST(&rw->lock_object, 0))
CTR4(KTR_LOCK,
"%s: %p succeed %p -> %p", __func__,
@ -289,6 +281,8 @@ _rw_rlock(struct rwlock *rw, const char *file, int line)
cpu_spinwait();
continue;
}
lock_profile_obtain_lock_failed(&rw->lock_object,
&contested, &waittime);
#ifdef ADAPTIVE_RWLOCKS
/*
@ -301,10 +295,6 @@ _rw_rlock(struct rwlock *rw, const char *file, int line)
if (LOCK_LOG_TEST(&rw->lock_object, 0))
CTR3(KTR_LOCK, "%s: spinning on %p held by %p",
__func__, rw, owner);
#ifdef LOCK_PROFILING_SHARED
lock_profile_obtain_lock_failed(&rw->lock_object,
&contested, &waittime);
#endif
while ((struct thread*)RW_OWNER(rw->rw_lock) == owner &&
TD_IS_RUNNING(owner))
cpu_spinwait();
@ -369,10 +359,6 @@ _rw_rlock(struct rwlock *rw, const char *file, int line)
if (LOCK_LOG_TEST(&rw->lock_object, 0))
CTR2(KTR_LOCK, "%s: %p blocking on turnstile", __func__,
rw);
#ifdef LOCK_PROFILING_SHARED
lock_profile_obtain_lock_failed(&rw->lock_object, &contested,
&waittime);
#endif
turnstile_wait(ts, rw_owner(rw), TS_SHARED_QUEUE);
if (LOCK_LOG_TEST(&rw->lock_object, 0))
CTR2(KTR_LOCK, "%s: %p resuming from turnstile",
@ -384,7 +370,8 @@ _rw_rlock(struct rwlock *rw, const char *file, int line)
* however. turnstiles don't like owners changing between calls to
* turnstile_wait() currently.
*/
lock_profile_obtain_lock_success( &rw->lock_object, contested,
waittime, file, line);
LOCK_LOG_LOCK("RLOCK", &rw->lock_object, 0, 0, file, line);
WITNESS_LOCK(&rw->lock_object, 0, file, line);
curthread->td_locks++;
@ -431,9 +418,6 @@ _rw_runlock(struct rwlock *rw, const char *file, int line)
*/
KASSERT(!(x & RW_LOCK_READ_WAITERS),
("%s: waiting readers", __func__));
#ifdef LOCK_PROFILING_SHARED
lock_profile_release_lock(&rw->lock_object);
#endif
/*
* If there aren't any waiters for a write lock, then try
@ -510,6 +494,7 @@ _rw_runlock(struct rwlock *rw, const char *file, int line)
turnstile_chain_unlock(&rw->lock_object);
break;
}
lock_profile_release_lock(&rw->lock_object);
}
/*
@ -544,6 +529,8 @@ _rw_wlock_hard(struct rwlock *rw, uintptr_t tid, const char *file, int line)
rw->lock_object.lo_name, (void *)rw->rw_lock, file, line);
while (!_rw_write_lock(rw, tid)) {
lock_profile_obtain_lock_failed(&rw->lock_object,
&contested, &waittime);
#ifdef ADAPTIVE_RWLOCKS
/*
* If the lock is write locked and the owner is
@ -556,8 +543,6 @@ _rw_wlock_hard(struct rwlock *rw, uintptr_t tid, const char *file, int line)
if (LOCK_LOG_TEST(&rw->lock_object, 0))
CTR3(KTR_LOCK, "%s: spinning on %p held by %p",
__func__, rw, owner);
lock_profile_obtain_lock_failed(&rw->lock_object,
&contested, &waittime);
while ((struct thread*)RW_OWNER(rw->rw_lock) == owner &&
TD_IS_RUNNING(owner))
cpu_spinwait();
@ -641,8 +626,6 @@ _rw_wlock_hard(struct rwlock *rw, uintptr_t tid, const char *file, int line)
if (LOCK_LOG_TEST(&rw->lock_object, 0))
CTR2(KTR_LOCK, "%s: %p blocking on turnstile", __func__,
rw);
lock_profile_obtain_lock_failed(&rw->lock_object, &contested,
&waittime);
turnstile_wait(ts, rw_owner(rw), TS_EXCLUSIVE_QUEUE);
if (LOCK_LOG_TEST(&rw->lock_object, 0))
CTR2(KTR_LOCK, "%s: %p resuming from turnstile",

34
sys/kern/kern_sx.c

@ -302,11 +302,8 @@ _sx_sunlock(struct sx *sx, const char *file, int line)
curthread->td_locks--;
WITNESS_UNLOCK(&sx->lock_object, 0, file, line);
LOCK_LOG_LOCK("SUNLOCK", &sx->lock_object, 0, 0, file, line);
#ifdef LOCK_PROFILING_SHARED
if (SX_SHARERS(sx->sx_lock) == 1)
lock_profile_release_lock(&sx->lock_object);
#endif
__sx_sunlock(sx, file, line);
lock_profile_release_lock(&sx->lock_object);
}
void
@ -450,6 +447,8 @@ _sx_xlock_hard(struct sx *sx, uintptr_t tid, int opts, const char *file,
sx->lock_object.lo_name, (void *)sx->sx_lock, file, line);
while (!atomic_cmpset_acq_ptr(&sx->sx_lock, SX_LOCK_UNLOCKED, tid)) {
lock_profile_obtain_lock_failed(&sx->lock_object, &contested,
&waittime);
#ifdef ADAPTIVE_SX
/*
* If the lock is write locked and the owner is
@ -467,8 +466,6 @@ _sx_xlock_hard(struct sx *sx, uintptr_t tid, int opts, const char *file,
"%s: spinning on %p held by %p",
__func__, sx, owner);
GIANT_SAVE();
lock_profile_obtain_lock_failed(
&sx->lock_object, &contested, &waittime);
while (SX_OWNER(sx->sx_lock) == x &&
TD_IS_RUNNING(owner))
cpu_spinwait();
@ -555,8 +552,6 @@ _sx_xlock_hard(struct sx *sx, uintptr_t tid, int opts, const char *file,
__func__, sx);
GIANT_SAVE();
lock_profile_obtain_lock_failed(&sx->lock_object, &contested,
&waittime);
sleepq_add(&sx->lock_object, NULL, sx->lock_object.lo_name,
SLEEPQ_SX | ((opts & SX_INTERRUPTIBLE) ?
SLEEPQ_INTERRUPTIBLE : 0), SQ_EXCLUSIVE_QUEUE);
@ -648,10 +643,8 @@ _sx_slock_hard(struct sx *sx, int opts, const char *file, int line)
#ifdef ADAPTIVE_SX
volatile struct thread *owner;
#endif
#ifdef LOCK_PROFILING_SHARED
uint64_t waittime = 0;
int contested = 0;
#endif
uintptr_t x;
int error = 0;
@ -672,12 +665,6 @@ _sx_slock_hard(struct sx *sx, int opts, const char *file, int line)
MPASS(!(x & SX_LOCK_SHARED_WAITERS));
if (atomic_cmpset_acq_ptr(&sx->sx_lock, x,
x + SX_ONE_SHARER)) {
#ifdef LOCK_PROFILING_SHARED
if (SX_SHARERS(x) == 0)
lock_profile_obtain_lock_success(
&sx->lock_object, contested,
waittime, file, line);
#endif
if (LOCK_LOG_TEST(&sx->lock_object, 0))
CTR4(KTR_LOCK,
"%s: %p succeed %p -> %p", __func__,
@ -687,6 +674,8 @@ _sx_slock_hard(struct sx *sx, int opts, const char *file, int line)
}
continue;
}
lock_profile_obtain_lock_failed(&sx->lock_object, &contested,
&waittime);
#ifdef ADAPTIVE_SX
/*
@ -694,7 +683,7 @@ _sx_slock_hard(struct sx *sx, int opts, const char *file, int line)
* the owner stops running or the state of the lock
* changes.
*/
else if (sx->lock_object.lo_flags & SX_ADAPTIVESPIN) {
if (sx->lock_object.lo_flags & SX_ADAPTIVESPIN) {
x = SX_OWNER(x);
owner = (struct thread *)x;
if (TD_IS_RUNNING(owner)) {
@ -703,10 +692,6 @@ _sx_slock_hard(struct sx *sx, int opts, const char *file, int line)
"%s: spinning on %p held by %p",
__func__, sx, owner);
GIANT_SAVE();
#ifdef LOCK_PROFILING_SHARED
lock_profile_obtain_lock_failed(
&sx->lock_object, &contested, &waittime);
#endif
while (SX_OWNER(sx->sx_lock) == x &&
TD_IS_RUNNING(owner))
cpu_spinwait();
@ -772,10 +757,6 @@ _sx_slock_hard(struct sx *sx, int opts, const char *file, int line)
__func__, sx);
GIANT_SAVE();
#ifdef LOCK_PROFILING_SHARED
lock_profile_obtain_lock_failed(&sx->lock_object, &contested,
&waittime);
#endif
sleepq_add(&sx->lock_object, NULL, sx->lock_object.lo_name,
SLEEPQ_SX | ((opts & SX_INTERRUPTIBLE) ?
SLEEPQ_INTERRUPTIBLE : 0), SQ_SHARED_QUEUE);
@ -795,6 +776,9 @@ _sx_slock_hard(struct sx *sx, int opts, const char *file, int line)
CTR2(KTR_LOCK, "%s: %p resuming from sleep queue",
__func__, sx);
}
if (error == 0)
lock_profile_obtain_lock_success(&sx->lock_object, contested,
waittime, file, line);
GIANT_RESTORE();
return (error);

2
sys/kern/kern_thread.c

@ -555,6 +555,8 @@ thread_link(struct thread *td, struct proc *p)
td->td_flags = TDF_INMEM;
LIST_INIT(&td->td_contested);
LIST_INIT(&td->td_lprof[0]);
LIST_INIT(&td->td_lprof[1]);
sigqueue_init(&td->td_sigqueue, p);
callout_init(&td->td_slpcallout, CALLOUT_MPSAFE);
TAILQ_INSERT_HEAD(&p->p_threads, td, td_plist);

7
sys/kern/sched_4bsd.c

@ -878,9 +878,11 @@ sched_switch(struct thread *td, struct thread *newtd, int flags)
if (PMC_PROC_IS_USING_PMCS(td->td_proc))
PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT);
#endif
/* I feel sleepy */
lock_profile_release_lock(&sched_lock.lock_object);
cpu_switch(td, newtd, td->td_lock);
lock_profile_obtain_lock_success(&sched_lock.lock_object,
0, 0, __FILE__, __LINE__);
/*
* Where am I? What year is it?
* We are in the same thread that went to sleep above,
@ -1375,6 +1377,7 @@ sched_throw(struct thread *td)
mtx_lock_spin(&sched_lock);
spinlock_exit();
} else {
lock_profile_release_lock(&sched_lock.lock_object);
MPASS(td->td_lock == &sched_lock);
}
mtx_assert(&sched_lock, MA_OWNED);
@ -1394,6 +1397,8 @@ sched_fork_exit(struct thread *td)
*/
td->td_oncpu = PCPU_GET(cpuid);
sched_lock.mtx_lock = (uintptr_t)td;
lock_profile_obtain_lock_success(&sched_lock.lock_object,
0, 0, __FILE__, __LINE__);
THREAD_LOCK_ASSERT(td, MA_OWNED | MA_NOTRECURSED);
}

6
sys/kern/sched_ule.c

@ -1894,6 +1894,7 @@ sched_switch(struct thread *td, struct thread *newtd, int flags)
if (PMC_PROC_IS_USING_PMCS(td->td_proc))
PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT);
#endif
lock_profile_release_lock(&TDQ_LOCKPTR(tdq)->lock_object);
TDQ_LOCKPTR(tdq)->mtx_lock = (uintptr_t)newtd;
cpu_switch(td, newtd, mtx);
/*
@ -1903,6 +1904,8 @@ sched_switch(struct thread *td, struct thread *newtd, int flags)
*/
cpuid = PCPU_GET(cpuid);
tdq = TDQ_CPU(cpuid);
lock_profile_obtain_lock_success(
&TDQ_LOCKPTR(tdq)->lock_object, 0, 0, __FILE__, __LINE__);
#ifdef HWPMC_HOOKS
if (PMC_PROC_IS_USING_PMCS(td->td_proc))
PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN);
@ -2618,6 +2621,7 @@ sched_throw(struct thread *td)
} else {
MPASS(td->td_lock == TDQ_LOCKPTR(tdq));
tdq_load_rem(tdq, td->td_sched);
lock_profile_release_lock(&TDQ_LOCKPTR(tdq)->lock_object);
}
KASSERT(curthread->td_md.md_spinlock_count == 1, ("invalid count"));
newtd = choosethread();
@ -2650,6 +2654,8 @@ sched_fork_exit(struct thread *td)
MPASS(td->td_lock == TDQ_LOCKPTR(tdq));
td->td_oncpu = cpuid;
TDQ_LOCK_ASSERT(tdq, MA_OWNED | MA_NOTRECURSED);
lock_profile_obtain_lock_success(
&TDQ_LOCKPTR(tdq)->lock_object, 0, 0, __FILE__, __LINE__);
}
static SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RW, 0,

658
sys/kern/subr_lock.c

@ -40,17 +40,24 @@ __FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/linker_set.h>
#include <sys/lock.h>
#include <sys/sbuf.h>
#include <sys/sysctl.h>
#include <sys/lock_profile.h>
#include <sys/malloc.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#ifdef DDB
#include <ddb/ddb.h>
#endif
#include <machine/cpufunc.h>
CTASSERT(LOCK_CLASS_MAX == 15);
struct lock_class *lock_classes[LOCK_CLASS_MAX + 1] = {
@ -62,136 +69,6 @@ struct lock_class *lock_classes[LOCK_CLASS_MAX + 1] = {
&lock_class_lockmgr,
};
#ifdef LOCK_PROFILING
#include <machine/cpufunc.h>
SYSCTL_NODE(_debug, OID_AUTO, lock, CTLFLAG_RD, NULL, "lock debugging");
SYSCTL_NODE(_debug_lock, OID_AUTO, prof, CTLFLAG_RD, NULL, "lock profiling");
int lock_prof_enable = 0;
SYSCTL_INT(_debug_lock_prof, OID_AUTO, enable, CTLFLAG_RW,
&lock_prof_enable, 0, "Enable lock profiling");
/*
* lprof_buf is a static pool of profiling records to avoid possible
* reentrance of the memory allocation functions.
*
* Note: NUM_LPROF_BUFFERS must be smaller than LPROF_HASH_SIZE.
*/
struct lock_prof lprof_buf[LPROF_HASH_SIZE];
static int allocated_lprof_buf;
struct mtx lprof_locks[LPROF_LOCK_SIZE];
/* SWAG: sbuf size = avg stat. line size * number of locks */
#define LPROF_SBUF_SIZE 256 * 400
static int lock_prof_acquisitions;
SYSCTL_INT(_debug_lock_prof, OID_AUTO, acquisitions, CTLFLAG_RD,
&lock_prof_acquisitions, 0, "Number of lock acquistions recorded");
static int lock_prof_records;
SYSCTL_INT(_debug_lock_prof, OID_AUTO, records, CTLFLAG_RD,
&lock_prof_records, 0, "Number of profiling records");
static int lock_prof_maxrecords = LPROF_HASH_SIZE;
SYSCTL_INT(_debug_lock_prof, OID_AUTO, maxrecords, CTLFLAG_RD,
&lock_prof_maxrecords, 0, "Maximum number of profiling records");
static int lock_prof_rejected;
SYSCTL_INT(_debug_lock_prof, OID_AUTO, rejected, CTLFLAG_RD,
&lock_prof_rejected, 0, "Number of rejected profiling records");
static int lock_prof_hashsize = LPROF_HASH_SIZE;
SYSCTL_INT(_debug_lock_prof, OID_AUTO, hashsize, CTLFLAG_RD,
&lock_prof_hashsize, 0, "Hash size");
static int lock_prof_collisions = 0;
SYSCTL_INT(_debug_lock_prof, OID_AUTO, collisions, CTLFLAG_RD,
&lock_prof_collisions, 0, "Number of hash collisions");
#ifndef USE_CPU_NANOSECONDS
u_int64_t
nanoseconds(void)
{
struct timespec tv;
nanotime(&tv);
return (tv.tv_sec * (u_int64_t)1000000000 + tv.tv_nsec);
}
#endif
static int
dump_lock_prof_stats(SYSCTL_HANDLER_ARGS)
{
struct sbuf *sb;
int error, i;
static int multiplier = 1;
const char *p;
if (allocated_lprof_buf == 0)
return (SYSCTL_OUT(req, "No locking recorded",
sizeof("No locking recorded")));
retry_sbufops:
sb = sbuf_new(NULL, NULL, LPROF_SBUF_SIZE * multiplier, SBUF_FIXEDLEN);
sbuf_printf(sb, "\n%6s %12s %12s %11s %5s %5s %12s %12s %s\n",
"max", "total", "wait_total", "count", "avg", "wait_avg", "cnt_hold", "cnt_lock", "name");
for (i = 0; i < LPROF_HASH_SIZE; ++i) {
if (lprof_buf[i].name == NULL)
continue;
for (p = lprof_buf[i].file;
p != NULL && strncmp(p, "../", 3) == 0; p += 3)
/* nothing */ ;
sbuf_printf(sb, "%6ju %12ju %12ju %11ju %5ju %5ju %12ju %12ju %s:%d (%s:%s)\n",
lprof_buf[i].cnt_max / 1000,
lprof_buf[i].cnt_tot / 1000,
lprof_buf[i].cnt_wait / 1000,
lprof_buf[i].cnt_cur,
lprof_buf[i].cnt_cur == 0 ? (uintmax_t)0 :
lprof_buf[i].cnt_tot / (lprof_buf[i].cnt_cur * 1000),
lprof_buf[i].cnt_cur == 0 ? (uintmax_t)0 :
lprof_buf[i].cnt_wait / (lprof_buf[i].cnt_cur * 1000),
lprof_buf[i].cnt_contest_holding,
lprof_buf[i].cnt_contest_locking,
p, lprof_buf[i].line,
lprof_buf[i].type,
lprof_buf[i].name);
if (sbuf_overflowed(sb)) {
sbuf_delete(sb);
multiplier++;
goto retry_sbufops;
}
}
sbuf_finish(sb);
error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
sbuf_delete(sb);
return (error);
}
static int
reset_lock_prof_stats(SYSCTL_HANDLER_ARGS)
{
int error, v;
if (allocated_lprof_buf == 0)
return (0);
v = 0;
error = sysctl_handle_int(oidp, &v, 0, req);
if (error)
return (error);
if (req->newptr == NULL)
return (error);
if (v == 0)
return (0);
bzero(lprof_buf, LPROF_HASH_SIZE*sizeof(*lprof_buf));
allocated_lprof_buf = 0;
return (0);
}
SYSCTL_PROC(_debug_lock_prof, OID_AUTO, stats, CTLTYPE_STRING | CTLFLAG_RD,
NULL, 0, dump_lock_prof_stats, "A", "Lock profiling statistics");
SYSCTL_PROC(_debug_lock_prof, OID_AUTO, reset, CTLTYPE_INT | CTLFLAG_RW,
NULL, 0, reset_lock_prof_stats, "I", "Reset lock profiling statistics");
#endif
void
lock_init(struct lock_object *lock, struct lock_class *class, const char *name,
const char *type, int flags)
@ -216,7 +93,6 @@ lock_init(struct lock_object *lock, struct lock_class *class, const char *name,
lock->lo_flags |= flags | LO_INITIALIZED;
LOCK_LOG_INIT(lock, 0);
WITNESS_INIT(lock);
lock_profile_object_init(lock, class, name);
}
void
@ -224,7 +100,6 @@ lock_destroy(struct lock_object *lock)
{
KASSERT(lock_initalized(lock), ("lock %p is not initialized", lock));
lock_profile_object_destroy(lock);
WITNESS_DESTROY(lock);
LOCK_LOG_DESTROY(lock, 0);
lock->lo_flags &= ~LO_INITIALIZED;
@ -253,17 +128,376 @@ DB_SHOW_COMMAND(lock, db_show_lock)
#endif
#ifdef LOCK_PROFILING
void _lock_profile_obtain_lock_success(struct lock_object *lo, int contested, uint64_t waittime, const char *file, int line)
{
struct lock_profile_object *l = &lo->lo_profile_obj;
lo->lo_profile_obj.lpo_contest_holding = 0;
/*
* One object per-thread for each lock the thread owns. Tracks individual
* lock instances.
*/
struct lock_profile_object {
LIST_ENTRY(lock_profile_object) lpo_link;
struct lock_object *lpo_obj;
const char *lpo_file;
int lpo_line;
uint16_t lpo_ref;
uint16_t lpo_cnt;
u_int64_t lpo_acqtime;
u_int64_t lpo_waittime;
u_int lpo_contest_locking;
};
/*
* One lock_prof for each (file, line, lock object) triple.
*/
struct lock_prof {
SLIST_ENTRY(lock_prof) link;
const char *file;
const char *name;
int line;
int ticks;
const char *type;
uintmax_t cnt_max;
uintmax_t cnt_tot;
uintmax_t cnt_wait;
uintmax_t cnt_cur;
uintmax_t cnt_contest_locking;
};
SLIST_HEAD(lphead, lock_prof);
#define LPROF_HASH_SIZE 4096
#define LPROF_HASH_MASK (LPROF_HASH_SIZE - 1)
#define LPROF_CACHE_SIZE 4096
/*
* Array of objects and profs for each type of object for each cpu. Spinlocks
* are handled seperately because a thread may be preempted and acquire a
* spinlock while in the lock profiling code of a non-spinlock. In this way
* we only need a critical section to protect the per-cpu lists.
*/
struct lock_prof_type {
struct lphead lpt_lpalloc;
struct lpohead lpt_lpoalloc;
struct lphead lpt_hash[LPROF_HASH_SIZE];
struct lock_prof lpt_prof[LPROF_CACHE_SIZE];
struct lock_profile_object lpt_objs[LPROF_CACHE_SIZE];
};
struct lock_prof_cpu {
struct lock_prof_type lpc_types[2]; /* One for spin one for other. */
};
struct lock_prof_cpu *lp_cpu[MAXCPU];
int lock_prof_enable = 0;
/* SWAG: sbuf size = avg stat. line size * number of locks */
#define LPROF_SBUF_SIZE 256 * 400
static int lock_prof_rejected;
static int lock_prof_skipspin;
static int lock_prof_skipcount;
#ifndef USE_CPU_NANOSECONDS
u_int64_t
nanoseconds(void)
{
struct bintime bt;
u_int64_t ns;
binuptime(&bt);
/* From bintime2timespec */
ns = bt.sec * (u_int64_t)1000000000;
ns += ((uint64_t)1000000000 * (uint32_t)(bt.frac >> 32)) >> 32;
return (ns);
}
#endif
static void
lock_prof_init_type(struct lock_prof_type *type)
{
int i;
SLIST_INIT(&type->lpt_lpalloc);
LIST_INIT(&type->lpt_lpoalloc);
for (i = 0; i < LPROF_CACHE_SIZE; i++) {
SLIST_INSERT_HEAD(&type->lpt_lpalloc, &type->lpt_prof[i],
link);
LIST_INSERT_HEAD(&type->lpt_lpoalloc, &type->lpt_objs[i],
lpo_link);
}
}
static void
lock_prof_init(void *arg)
{
int cpu;
for (cpu = 0; cpu <= mp_maxid; cpu++) {
lp_cpu[cpu] = malloc(sizeof(*lp_cpu[cpu]), M_DEVBUF,
M_WAITOK | M_ZERO);
lock_prof_init_type(&lp_cpu[cpu]->lpc_types[0]);
lock_prof_init_type(&lp_cpu[cpu]->lpc_types[1]);
}
}
SYSINIT(lockprof, SI_SUB_SMP, SI_ORDER_ANY, lock_prof_init, NULL);
static void
lock_prof_reset(void)
{
struct lock_prof_cpu *lpc;
int enabled, i, cpu;
enabled = lock_prof_enable;
lock_prof_enable = 0;
for (cpu = 0; cpu <= mp_maxid; cpu++) {
lpc = lp_cpu[cpu];
for (i = 0; i < LPROF_CACHE_SIZE; i++) {
LIST_REMOVE(&lpc->lpc_types[0].lpt_objs[i], lpo_link);
LIST_REMOVE(&lpc->lpc_types[1].lpt_objs[i], lpo_link);
}
bzero(lpc, sizeof(*lpc));
lock_prof_init_type(&lpc->lpc_types[0]);
lock_prof_init_type(&lpc->lpc_types[1]);
}
lock_prof_enable = enabled;
}
static void
lock_prof_output(struct lock_prof *lp, struct sbuf *sb)
{
const char *p;
for (p = lp->file; p != NULL && strncmp(p, "../", 3) == 0; p += 3);
sbuf_printf(sb,
"%6ju %12ju %12ju %11ju %5ju %5ju %12ju %12ju %s:%d (%s:%s)\n",
lp->cnt_max / 1000, lp->cnt_tot / 1000,
lp->cnt_wait / 1000, lp->cnt_cur,
lp->cnt_cur == 0 ? (uintmax_t)0 :
lp->cnt_tot / (lp->cnt_cur * 1000),
lp->cnt_cur == 0 ? (uintmax_t)0 :
lp->cnt_wait / (lp->cnt_cur * 1000),
(uintmax_t)0, lp->cnt_contest_locking,
p, lp->line, lp->type, lp->name);
}
static void
lock_prof_sum(struct lock_prof *match, struct lock_prof *dst, int hash,
int spin, int t)
{
struct lock_prof_type *type;
struct lock_prof *l;
int cpu;
dst->file = match->file;
dst->line = match->line;
dst->type = match->type;
dst->name = match->name;
for (cpu = 0; cpu <= mp_maxid; cpu++) {
if (lp_cpu[cpu] == NULL)
continue;
type = &lp_cpu[cpu]->lpc_types[spin];
SLIST_FOREACH(l, &type->lpt_hash[hash], link) {
if (l->ticks == t)
continue;
if (l->file != match->file || l->line != match->line ||
l->name != match->name || l->type != match->type)
continue;
l->ticks = t;
if (l->cnt_max > dst->cnt_max)
dst->cnt_max = l->cnt_max;
dst->cnt_tot += l->cnt_tot;
dst->cnt_wait += l->cnt_wait;
dst->cnt_cur += l->cnt_cur;
dst->cnt_contest_locking += l->cnt_contest_locking;
}
}
if (contested)
lo->lo_profile_obj.lpo_contest_locking++;
l->lpo_filename = file;
l->lpo_lineno = line;
}
static void
lock_prof_type_stats(struct lock_prof_type *type, struct sbuf *sb, int spin,
int t)
{
struct lock_prof *l;
int i;
for (i = 0; i < LPROF_HASH_SIZE; ++i) {
SLIST_FOREACH(l, &type->lpt_hash[i], link) {
struct lock_prof lp = {};
if (l->ticks == t)
continue;
lock_prof_sum(l, &lp, i, spin, t);
lock_prof_output(&lp, sb);
if (sbuf_overflowed(sb))
return;
}
}
}
static int
dump_lock_prof_stats(SYSCTL_HANDLER_ARGS)
{
static int multiplier = 1;
struct sbuf *sb;
int error, cpu, t;
retry_sbufops:
sb = sbuf_new(NULL, NULL, LPROF_SBUF_SIZE * multiplier, SBUF_FIXEDLEN);
sbuf_printf(sb, "\n%6s %12s %12s %11s %5s %5s %12s %12s %s\n",
"max", "total", "wait_total", "count", "avg", "wait_avg", "cnt_hold", "cnt_lock", "name");
t = ticks;
for (cpu = 0; cpu <= mp_maxid; cpu++) {
if (lp_cpu[cpu] == NULL)
continue;
lock_prof_type_stats(&lp_cpu[cpu]->lpc_types[0], sb, 0, t);
lock_prof_type_stats(&lp_cpu[cpu]->lpc_types[1], sb, 1, t);
if (sbuf_overflowed(sb)) {
sbuf_delete(sb);
multiplier++;
goto retry_sbufops;
}
}
sbuf_finish(sb);
error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
sbuf_delete(sb);
return (error);
}
static int
enable_lock_prof(SYSCTL_HANDLER_ARGS)
{
int error, v;
v = lock_prof_enable;
error = sysctl_handle_int(oidp, &v, v, req);
if (error)
return (error);
if (req->newptr == NULL)
return (error);
if (v == lock_prof_enable)
return (0);
if (v == 1)
lock_prof_reset();
lock_prof_enable = !!v;
return (0);
}
static int
reset_lock_prof_stats(SYSCTL_HANDLER_ARGS)
{
int error, v;
v = 0;
error = sysctl_handle_int(oidp, &v, 0, req);
if (error)
return (error);
if (req->newptr == NULL)
return (error);
if (v == 0)
return (0);
lock_prof_reset();
return (0);
}
static struct lock_prof *
lock_profile_lookup(struct lock_object *lo, int spin, const char *file,
int line)
{
const char *unknown = "(unknown)";
struct lock_prof_type *type;
struct lock_prof *lp;
struct lphead *head;
const char *p;
u_int hash;
p = file;
if (p == NULL || *p == '\0')
p = unknown;
hash = (uintptr_t)lo->lo_name * 31 + (uintptr_t)p * 31 + line;
hash &= LPROF_HASH_MASK;
type = &lp_cpu[PCPU_GET(cpuid)]->lpc_types[spin];
head = &type->lpt_hash[hash];
SLIST_FOREACH(lp, head, link) {
if (lp->line == line && lp->file == p &&
lp->name == lo->lo_name)
return (lp);
}
lp = SLIST_FIRST(&type->lpt_lpalloc);
if (lp == NULL) {
lock_prof_rejected++;
return (lp);
}
SLIST_REMOVE_HEAD(&type->lpt_lpalloc, link);
lp->file = p;
lp->line = line;
lp->type = lo->lo_type;
lp->name = lo->lo_name;
SLIST_INSERT_HEAD(&type->lpt_hash[hash], lp, link);
return (lp);
}
static struct lock_profile_object *
lock_profile_object_lookup(struct lock_object *lo, int spin, const char *file,
int line)
{
struct lock_profile_object *l;
struct lock_prof_type *type;
struct lpohead *head;
head = &curthread->td_lprof[spin];
LIST_FOREACH(l, head, lpo_link)
if (l->lpo_obj == lo && l->lpo_file == file &&
l->lpo_line == line)
return (l);
critical_enter();
type = &lp_cpu[PCPU_GET(cpuid)]->lpc_types[spin];
l = LIST_FIRST(&type->lpt_lpoalloc);
if (l == NULL) {
lock_prof_rejected++;
critical_exit();
return (NULL);
}
LIST_REMOVE(l, lpo_link);
critical_exit();
l->lpo_obj = lo;
l->lpo_file = file;
l->lpo_line = line;
l->lpo_cnt = 0;
LIST_INSERT_HEAD(head, l, lpo_link);
return (l);
}
void
lock_profile_obtain_lock_success(struct lock_object *lo, int contested,
uint64_t waittime, const char *file, int line)
{
static int lock_prof_count;
struct lock_profile_object *l;
int spin;
/* don't reset the timer when/if recursing */
if (!lock_prof_enable || (lo->lo_flags & LO_NOPROFILE))
return;
if (lock_prof_skipcount &&
(++lock_prof_count % lock_prof_skipcount) == 0)
return;
spin = LOCK_CLASS(lo) == &lock_class_mtx_spin;
if (spin && lock_prof_skipspin == 1)
return;
l = lock_profile_object_lookup(lo, spin, file, line);
if (l == NULL)
return;
l->lpo_cnt++;
if (++l->lpo_ref > 1)
return;
l->lpo_contest_locking = contested;
l->lpo_acqtime = nanoseconds();
if (waittime && (l->lpo_acqtime > waittime))
l->lpo_waittime = l->lpo_acqtime - waittime;
@ -271,87 +505,65 @@ void _lock_profile_obtain_lock_success(struct lock_object *lo, int contested, ui
l->lpo_waittime = 0;
}
void _lock_profile_release_lock(struct lock_object *lo)
void
lock_profile_release_lock(struct lock_object *lo)
{
struct lock_profile_object *l = &lo->lo_profile_obj;
struct lock_profile_object *l;
struct lock_prof_type *type;
struct lock_prof *lp;
u_int64_t holdtime;
struct lpohead *head;
int spin;
if (l->lpo_acqtime) {
const char *unknown = "(unknown)";
u_int64_t acqtime, now, waittime;
struct lock_prof *mpp;
u_int hash;
const char *p = l->lpo_filename;
int collision = 0;
now = nanoseconds();
acqtime = l->lpo_acqtime;
waittime = l->lpo_waittime;
if (now <= acqtime)
return;
if (p == NULL || *p == '\0')
p = unknown;
hash = (l->lpo_namehash * 31 * 31 + (uintptr_t)p * 31 + l->lpo_lineno) & LPROF_HASH_MASK;
mpp = &lprof_buf[hash];
while (mpp->name != NULL) {
if (mpp->line == l->lpo_lineno &&
mpp->file == p &&
mpp->namehash == l->lpo_namehash)
break;
/* If the lprof_hash entry is allocated to someone
* else, try the next one
*/
collision = 1;
hash = (hash + 1) & LPROF_HASH_MASK;
mpp = &lprof_buf[hash];
}
if (mpp->name == NULL) {
int buf;
buf = atomic_fetchadd_int(&allocated_lprof_buf, 1);
/* Just exit if we cannot get a trace buffer */
if (buf >= LPROF_HASH_SIZE) {
++lock_prof_rejected;
return;
}
mpp->file = p;
mpp->line = l->lpo_lineno;
mpp->namehash = l->lpo_namehash;
mpp->type = l->lpo_type;
mpp->name = lo->lo_name;
if (collision)
++lock_prof_collisions;
/*
* We might have raced someone else but who cares,
* they'll try again next time
*/
++lock_prof_records;
}
LPROF_LOCK(hash);
/*
* Record if the lock has been held longer now than ever
* before.
*/
if (now - acqtime > mpp->cnt_max)
mpp->cnt_max = now - acqtime;
mpp->cnt_tot += now - acqtime;
mpp->cnt_wait += waittime;
mpp->cnt_cur++;
/*
* There's a small race, really we should cmpxchg
* 0 with the current value, but that would bill
* the contention to the wrong lock instance if
* it followed this also.
*/
mpp->cnt_contest_holding += l->lpo_contest_holding;
mpp->cnt_contest_locking += l->lpo_contest_locking;
LPROF_UNLOCK(hash);
}
l->lpo_acqtime = 0;
l->lpo_waittime = 0;
l->lpo_contest_locking = 0;
l->lpo_contest_holding = 0;
if (!lock_prof_enable || (lo->lo_flags & LO_NOPROFILE))
return;
spin = LOCK_CLASS(lo) == &lock_class_mtx_spin;
head = &curthread->td_lprof[spin];
critical_enter();
LIST_FOREACH(l, head, lpo_link)
if (l->lpo_obj == lo)
break;
if (l == NULL)
goto out;
if (--l->lpo_ref > 0)
goto out;
lp = lock_profile_lookup(lo, spin, l->lpo_file, l->lpo_line);
if (lp == NULL)
goto release;
holdtime = nanoseconds() - l->lpo_acqtime;
if (holdtime < 0)
goto release;
/*
* Record if the lock has been held longer now than ever
* before.
*/
if (holdtime > lp->cnt_max)
lp->cnt_max = holdtime;
lp->cnt_tot += holdtime;
lp->cnt_wait += l->lpo_waittime;
lp->cnt_contest_locking += l->lpo_contest_locking;
lp->cnt_cur += l->lpo_cnt;
release:
LIST_REMOVE(l, lpo_link);
type = &lp_cpu[PCPU_GET(cpuid)]->lpc_types[spin];
LIST_INSERT_HEAD(&type->lpt_lpoalloc, l, lpo_link);
out:
critical_exit();
}
SYSCTL_NODE(_debug, OID_AUTO, lock, CTLFLAG_RD, NULL, "lock debugging");
SYSCTL_NODE(_debug_lock, OID_AUTO, prof, CTLFLAG_RD, NULL, "lock profiling");
SYSCTL_INT(_debug_lock_prof, OID_AUTO, skipspin, CTLFLAG_RW,
&lock_prof_skipspin, 0, "Skip profiling on spinlocks.");
SYSCTL_INT(_debug_lock_prof, OID_AUTO, skipcount, CTLFLAG_RW,
&lock_prof_skipcount, 0, "Sample approximately every N lock acquisitions.");
SYSCTL_INT(_debug_lock_prof, OID_AUTO, rejected, CTLFLAG_RD,
&lock_prof_rejected, 0, "Number of rejected profiling records");
SYSCTL_PROC(_debug_lock_prof, OID_AUTO, stats, CTLTYPE_STRING | CTLFLAG_RD,
NULL, 0, dump_lock_prof_stats, "A", "Lock profiling statistics");
SYSCTL_PROC(_debug_lock_prof, OID_AUTO, reset, CTLTYPE_INT | CTLFLAG_RW,
NULL, 0, reset_lock_prof_stats, "I", "Reset lock profiling statistics");
SYSCTL_PROC(_debug_lock_prof, OID_AUTO, enable, CTLTYPE_INT | CTLFLAG_RW,
NULL, 0, enable_lock_prof, "I", "Enable lock profiling");
#endif

25
sys/sys/_lock.h

@ -31,35 +31,10 @@
#ifndef _SYS__LOCK_H_
#define _SYS__LOCK_H_
struct lock_profile_object {
/*
* This does not result in variant structure sizes because
* MUTEX_PROFILING is in opt_global.h
*/
u_int64_t lpo_acqtime;
u_int64_t lpo_waittime;
const char *lpo_filename;
u_int lpo_namehash;
int lpo_lineno;
const char *lpo_type;
/*
* Fields relating to measuring contention on mutexes.
* holding must be accessed atomically since it's
* modified by threads that don't yet hold the mutex.
* locking is only modified and referenced while
* the mutex is held.
*/
u_int lpo_contest_holding;
u_int lpo_contest_locking;
};
struct lock_object {
const char *lo_name; /* Individual lock name. */
const char *lo_type; /* General lock type. */
u_int lo_flags;
#ifdef LOCK_PROFILING
struct lock_profile_object lo_profile_obj;
#endif
union { /* Data for witness. */
STAILQ_ENTRY(lock_object) lod_list;
struct witness *lod_witness;

149
sys/sys/lock_profile.h

@ -31,139 +31,54 @@
#ifndef _SYS_LOCK_PROFILE_H_
#define _SYS_LOCK_PROFILE_H_
#ifdef LOCK_PROFILING
#include <sys/stdint.h>
#include <sys/ktr.h>
#include <sys/mutex.h>
#include <machine/atomic.h>
#include <machine/cpufunc.h>
#ifdef _KERNEL
#ifndef LPROF_HASH_SIZE
#define LPROF_HASH_SIZE 4096
#define LPROF_HASH_MASK (LPROF_HASH_SIZE - 1)
#endif
struct lock_profile_object;
LIST_HEAD(lpohead, lock_profile_object);
#ifdef LOCK_PROFILING
#include <sys/lock.h>
#ifndef USE_CPU_NANOSECONDS
u_int64_t nanoseconds(void);
#endif
struct lock_prof {
const char *name;
const char *type;
const char *file;
u_int namehash;
int line;
uintmax_t cnt_max;
uintmax_t cnt_tot;
uintmax_t cnt_wait;
uintmax_t cnt_cur;
uintmax_t cnt_contest_holding;
uintmax_t cnt_contest_locking;
};
extern struct lock_prof lprof_buf[LPROF_HASH_SIZE];
#define LPROF_SBUF_SIZE 256 * 400
/* We keep a smaller pool of spin mutexes for protecting the lprof hash entries */
#define LPROF_LOCK_SIZE 16
#define LPROF_LOCK_MASK (LPROF_LOCK_SIZE - 1)
#define LPROF_LHASH(hash) ((hash) & LPROF_LOCK_MASK)
#define LPROF_LOCK(hash) mtx_lock_spin(&lprof_locks[LPROF_LHASH(hash)])
#define LPROF_UNLOCK(hash) mtx_unlock_spin(&lprof_locks[LPROF_LHASH(hash)])
#ifdef _KERNEL
extern struct mtx lprof_locks[LPROF_LOCK_SIZE];
extern int lock_prof_enable;
void _lock_profile_obtain_lock_success(struct lock_object *lo, int contested, uint64_t waittime, const char *file, int line);
void _lock_profile_update_wait(struct lock_object *lo, uint64_t waitstart);
void _lock_profile_release_lock(struct lock_object *lo);
void lock_profile_obtain_lock_success(struct lock_object *lo, int contested,
uint64_t waittime, const char *file, int line);
void lock_profile_release_lock(struct lock_object *lo);
static inline void lock_profile_object_init(struct lock_object *lo, struct lock_class *class, const char *name) {
const char *p;
u_int hash = 0;
struct lock_profile_object *l = &lo->lo_profile_obj;
l->lpo_acqtime = 0;
l->lpo_waittime = 0;
l->lpo_filename = NULL;
l->lpo_lineno = 0;
l->lpo_contest_holding = 0;
l->lpo_contest_locking = 0;
l->lpo_type = class->lc_name;
/* Hash the mutex name to an int so we don't have to strcmp() it repeatedly */
for (p = name; *p != '\0'; p++)
hash = 31 * hash + *p;
l->lpo_namehash = hash;
#if 0
if (opts & MTX_PROFILE)
l->lpo_stack = stack_create();
#endif
}
static inline void
lock_profile_object_destroy(struct lock_object *lo)
static inline void
lock_profile_obtain_lock_failed(struct lock_object *lo, int *contested,
uint64_t *waittime)
{
#if 0
struct lock_profile_object *l = &lo->lo_profile_obj;
if (lo->lo_flags & LO_PROFILE)
stack_destroy(l->lpo_stack);
#endif
if (!lock_prof_enable || (lo->lo_flags & LO_NOPROFILE) || *contested)
return;
*waittime = nanoseconds();
*contested = 1;
}
static inline void lock_profile_obtain_lock_failed(struct lock_object *lo, int *contested,
uint64_t *waittime)
{
struct lock_profile_object *l = &lo->lo_profile_obj;
if (!(lo->lo_flags & LO_NOPROFILE) && lock_prof_enable &&
*contested == 0) {
*waittime = nanoseconds();
atomic_add_int(&l->lpo_contest_holding, 1);
*contested = 1;
}
}
static inline void lock_profile_obtain_lock_success(struct lock_object *lo, int contested, uint64_t waittime, const char *file, int line)
{
/* don't reset the timer when/if recursing */
if (!(lo->lo_flags & LO_NOPROFILE) && lock_prof_enable &&
lo->lo_profile_obj.lpo_acqtime == 0) {
#ifdef LOCK_PROFILING_FAST
if (contested == 0)
return;
#endif
_lock_profile_obtain_lock_success(lo, contested, waittime, file, line);
}
}
static inline void lock_profile_release_lock(struct lock_object *lo)
{
struct lock_profile_object *l = &lo->lo_profile_obj;
if (!(lo->lo_flags & LO_NOPROFILE) && l->lpo_acqtime)
_lock_profile_release_lock(lo);
}
#endif /* _KERNEL */
#else /* !LOCK_PROFILING */
#ifdef _KERNEL
static inline void lock_profile_update_wait(struct lock_object *lo, uint64_t waitstart) {;}
static inline void lock_profile_update_contest_locking(struct lock_object *lo, int contested) {;}
static inline void lock_profile_release_lock(struct lock_object *lo) {;}
static inline void lock_profile_obtain_lock_failed(struct lock_object *lo, int *contested, uint64_t *waittime) {;}
static inline void lock_profile_obtain_lock_success(struct lock_object *lo, int contested, uint64_t waittime,
const char *file, int line) {;}
static inline void lock_profile_object_destroy(struct lock_object *lo) {;}
static inline void lock_profile_object_init(struct lock_object *lo, struct lock_class *class, const char *name) {;}
static inline void
lock_profile_release_lock(struct lock_object *lo)
{
}
#endif /* _KERNEL */
static inline void
lock_profile_obtain_lock_failed(struct lock_object *lo, int *contested, uint64_t *waittime)
{
}
static inline void
lock_profile_obtain_lock_success(struct lock_object *lo, int contested, uint64_t waittime,
const char *file, int line)
{
}
#endif /* !LOCK_PROFILING */
#endif /* _KERNEL */
#endif /* _SYS_LOCK_PROFILE_H_ */

2
sys/sys/proc.h

@ -45,6 +45,7 @@
#endif
#include <sys/queue.h>
#include <sys/_lock.h>
#include <sys/lock_profile.h>
#include <sys/_mutex.h>
#include <sys/priority.h>
#include <sys/rtprio.h> /* XXX. */
@ -298,6 +299,7 @@ struct thread {
struct td_sched *td_sched; /* (*) Scheduler-specific data. */
struct kaudit_record *td_ar; /* (k) Active audit record, if any. */
int td_syscalls; /* per-thread syscall count (used by NFS :)) */
struct lpohead td_lprof[2]; /* (a) lock profiling objects. */
};
struct mtx *thread_lock_block(struct thread *);

4
sys/sys/sx.h

@ -178,11 +178,9 @@ __sx_slock(struct sx *sx, int opts, const char *file, int line)
if (!(x & SX_LOCK_SHARED) ||
!atomic_cmpset_acq_ptr(&sx->sx_lock, x, x + SX_ONE_SHARER))
error = _sx_slock_hard(sx, opts, file, line);
#ifdef LOCK_PROFILING_SHARED
else if (SX_SHARERS(x) == 0)
else
lock_profile_obtain_lock_success(&sx->lock_object, 0, 0, file,
line);
#endif
return (error);
}