timer/linux: prevent 64-bit overflow #2720
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The linux timer code was multiplying the result of the x86 time stamp counter by 1000000 before dividing by the cpu frequency. This can cause us to overflow 64 bits if the time stamp counter grows larger than ~ 1.8e13 (about 8400 seconds after boot). To fix the issue the units of opal_timer_linux_freq have been changed to MHz. Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov> (cherry picked from commit 45c0588) Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
bosilca
approved these changes
Jan 12, 2017
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@hppritcha Good to go. |
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The linux timer code was multiplying the result of the x86 time stamp
counter by 1000000 before dividing by the cpu frequency. This can
cause us to overflow 64 bits if the time stamp counter grows larger
than ~ 1.8e13 (about 8400 seconds after boot). To fix the issue the
units of opal_timer_linux_freq have been changed to MHz.
Signed-off-by: Nathan Hjelm hjelmn@lanl.gov
(cherry picked from commit 45c0588)
Signed-off-by: Nathan Hjelm hjelmn@lanl.gov