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SubjectRe: [PATCH] Use of TSC with SMP and different CPU's
On Wed, 8 Mar 2000, Boris Okun wrote:

>This patch allows to use do_fast_gettimeofday() (and
>do_slow_gettimeofday as well) on SMP machines with processors running
>at different speeds. The original do_slow_gettimeofday() is not SMP safe
>and the original do_fast_gettimeofday() assumes that processors have the

It's not SMP safe but replacing the read_lock() with the write_lock() in
gettimeofday as I suggested you to try was only a workaround to verify
that was the real problem. This should be the right fix for the
slow_gettimofday SMP race against 2.2.15pre13:

ftp://ftp.*.kernel.org/pub/linux/kernel/people/andrea/patches/v2.2/2.2.15pre13/slow-gtod-SMP-race-1.gz

And this is the alone fix for the lost_ticks not accounted in settimeofday
that you noticed:

ftp://ftp.*.kernel.org/pub/linux/kernel/people/andrea/patches/v2.2/2.2.15pre13/stod-lost_ticks-1.gz

Andrea



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