Date: Sat, 16 Jul 2005 09:40:35 +0000 (UTC) From: Robert Watson <rwatson@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/vm uma_core.c Message-ID: <200507160940.j6G9eZ9d083133@repoman.freebsd.org>
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rwatson 2005-07-16 09:40:35 UTC
FreeBSD src repository
Modified files:
sys/vm uma_core.c
Log:
Move the unlocking of the zone mutex in sysctl_vm_zone_stats() so that
it covers the following of the uc_alloc/freebucket cache pointers.
Originally, I felt that the race wasn't helped by holding the mutex,
hence a comment in the code and not holding it across the cache access.
However, it does improve consistency, as while it doesn't prevent
bucket exchange, it does prevent bucket pointer invalidation. So a
race in gathering cache free space statistics still can occur, but not
one that follows an invalid bucket pointer, if the mutex is held.
Submitted by: yongari
MFC after: 1 week
Revision Changes Path
1.125 +9 -5 src/sys/vm/uma_core.c
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