Module Name: src Committed By: ad Date: Sat Nov 23 16:36:39 UTC 2019
Modified Files: src/sys/arch/amd64/amd64: lock_stubs.S src/sys/arch/i386/i386: lock_stubs.S Log Message: For this case during build.sh: rw_enter(lock, RW_READ); Having instrumented it, it turns out that >99.5% of the time the lock is completely unknowned. Make this assumption in the assembly stub for rw_enter(), and avoid the initial read of the lock word. Where there are existing read holds, we'll do an additional CMPXCHG but should already have the cache line in the EXCLUSIVE state. To generate a diff of this commit: cvs rdiff -u -r1.33 -r1.34 src/sys/arch/amd64/amd64/lock_stubs.S cvs rdiff -u -r1.30 -r1.31 src/sys/arch/i386/i386/lock_stubs.S Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files.