freebsd-nq/sys/kern/kern_lockstat.c
Mateusz Guzik 7640beb920 mtx: microoptimize lockstat handling in __mtx_lock_sleep
This saves a function call and multiple branches after the lock is acquired.
2017-02-17 14:55:59 +00:00

83 lines
3.3 KiB
C

/*-
* Copyright 2008-2009 Stacey Son <sson@FreeBSD.org>
*
* 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 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 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/lockstat.h>
#include <sys/sdt.h>
#include <sys/time.h>
SDT_PROVIDER_DEFINE(lockstat);
SDT_PROBE_DEFINE1(lockstat, , , adaptive__acquire, "struct mtx *");
SDT_PROBE_DEFINE1(lockstat, , , adaptive__release, "struct mtx *");
SDT_PROBE_DEFINE2(lockstat, , , adaptive__spin, "struct mtx *", "uint64_t");
SDT_PROBE_DEFINE2(lockstat, , , adaptive__block, "struct mtx *", "uint64_t");
SDT_PROBE_DEFINE1(lockstat, , , spin__acquire, "struct mtx *");
SDT_PROBE_DEFINE1(lockstat, , , spin__release, "struct mtx *");
SDT_PROBE_DEFINE2(lockstat, , , spin__spin, "struct mtx *", "uint64_t");
SDT_PROBE_DEFINE2(lockstat, , , rw__acquire, "struct rwlock *", "int");
SDT_PROBE_DEFINE2(lockstat, , , rw__release, "struct rwlock *", "int");
SDT_PROBE_DEFINE5(lockstat, , , rw__block, "struct rwlock *", "uint64_t", "int",
"int", "int");
SDT_PROBE_DEFINE2(lockstat, , , rw__spin, "struct rwlock *", "uint64_t");
SDT_PROBE_DEFINE1(lockstat, , , rw__upgrade, "struct rwlock *");
SDT_PROBE_DEFINE1(lockstat, , , rw__downgrade, "struct rwlock *");
SDT_PROBE_DEFINE2(lockstat, , , sx__acquire, "struct sx *", "int");
SDT_PROBE_DEFINE2(lockstat, , , sx__release, "struct sx *", "int");
SDT_PROBE_DEFINE5(lockstat, , , sx__block, "struct sx *", "uint64_t", "int",
"int", "int");
SDT_PROBE_DEFINE2(lockstat, , , sx__spin, "struct sx *", "uint64_t");
SDT_PROBE_DEFINE1(lockstat, , , sx__upgrade, "struct sx *");
SDT_PROBE_DEFINE1(lockstat, , , sx__downgrade, "struct sx *");
SDT_PROBE_DEFINE2(lockstat, , , thread__spin, "struct mtx *", "uint64_t");
volatile int __read_mostly lockstat_enabled;
uint64_t
lockstat_nsecs(struct lock_object *lo)
{
struct bintime bt;
uint64_t ns;
if (!lockstat_enabled)
return (0);
if ((lo->lo_flags & LO_NOPROFILE) != 0)
return (0);
binuptime(&bt);
ns = bt.sec * (uint64_t)1000000000;
ns += ((uint64_t)1000000000 * (uint32_t)(bt.frac >> 32)) >> 32;
return (ns);
}