diff options
| author | Andy Lutomirski <[email protected]> | 2011-05-23 09:31:27 -0400 |
|---|---|---|
| committer | Thomas Gleixner <[email protected]> | 2011-05-24 14:51:28 +0200 |
| commit | 0f51f2852ccf0fe38a02d340d0ba625e8e32a863 (patch) | |
| tree | 075e1f7c85c4deec2e0ab7509dcafa859842abd9 /tools/perf/util/scripting-engines/trace-event-perl.c | |
| parent | 3729db5ca2b2000c660e5a5d0eb68b1053212cab (diff) | |
x86-64: Vclock_gettime(CLOCK_MONOTONIC) can't ever see nsec < 0
vclock_gettime's do_monotonic helper can't ever generate a negative
nsec value, so it doesn't need to check whether it's negative. In
the CLOCK_MONOTONIC_COARSE case, ns can't ever exceed 2e9-1, so we
can avoid the loop entirely. This saves a single easily-predicted
branch.
Signed-off-by: Andy Lutomirski <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Borislav Petkov <[email protected]>
Link: http://lkml.kernel.org/r/%3Cd6d528d32c7a21618057cfc9005942a0fe5cb54a.1306156808.git.luto%40mit.edu%3E
Signed-off-by: Thomas Gleixner <[email protected]>
Diffstat (limited to 'tools/perf/util/scripting-engines/trace-event-perl.c')
0 files changed, 0 insertions, 0 deletions