Date: Tue, 27 Feb 2007 06:42:05 +0000 (UTC) From: Kip Macy <kmacy@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/conf options src/sys/kern kern_mutex.c kern_rwlock.c kern_sx.c src/sys/sys lock.h lock_profile.h Message-ID: <200702270642.l1R6g5Do027828@repoman.freebsd.org>
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kmacy 2007-02-27 06:42:05 UTC FreeBSD src repository Modified files: sys/conf options sys/kern kern_mutex.c kern_rwlock.c kern_sx.c sys/sys lock.h lock_profile.h Log: Further improvements to LOCK_PROFILING: - Fix missing initialization in kern_rwlock.c causing bogus times to be collected - Move updates to the lock hash to after the lock is released for spin mutexes, sleep mutexes, and sx locks - Add new kernel build option LOCK_PROFILE_FAST - only update lock profiling statistics when an acquisition is contended. This reduces the overhead of LOCK_PROFILING to increasing system time by 20%-25% which on "make -j8 kernel-toolchain" on a dual woodcrest is unmeasurable in terms of wall-clock time. Contrast this to enabling lock profiling without LOCK_PROFILE_FAST and I see a 5x-6x slowdown in wall-clock time. Revision Changes Path 1.577 +1 -0 src/sys/conf/options 1.181 +14 -3 src/sys/kern/kern_mutex.c 1.15 +2 -2 src/sys/kern/kern_rwlock.c 1.34 +20 -5 src/sys/kern/kern_sx.c 1.64 +1 -0 src/sys/sys/lock.h 1.10 +8 -1 src/sys/sys/lock_profile.h
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