Date: Sat, 4 Jun 2005 23:24:51 +0000 (UTC) From: Marius Strobl <marius@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/dev/mc146818 mc146818.c src/sys/kern subr_witness.c src/sys/sparc64/sparc64 rtc.c Message-ID: <200506042324.j54NOpbb099122@repoman.freebsd.org>
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marius 2005-06-04 23:24:50 UTC
FreeBSD src repository
Modified files:
sys/dev/mc146818 mc146818.c
sys/kern subr_witness.c
sys/sparc64/sparc64 rtc.c
Log:
After some input from bde@ and rereading the datasheet use a MTX_SPIN
mutex instead of a MTX_DEF one in order to defer preemption while
reading the date and time registers. If we don't manage to read them
within the time slot where we are guaranteed that no updates occur we
might actually read them during an update in which case the output is
undefined.
Revision Changes Path
1.4 +11 -11 src/sys/dev/mc146818/mc146818.c
1.195 +1 -0 src/sys/kern/subr_witness.c
1.4 +1 -1 src/sys/sparc64/sparc64/rtc.c
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