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| author | Andy Lutomirski <[email protected]> | 2014-09-05 22:13:56 +0000 |
|---|---|---|
| committer | H. Peter Anvin <[email protected]> | 2014-09-08 21:14:12 +0000 |
| commit | 1dcf74f6edfc3a9acd84d83d8865dd9e2a3b1d1e (patch) | |
| tree | 21030b6f0394f5b82cd17b96fd0008375b3f254b /tools/perf/scripts/python/check-perf-trace.py | |
| parent | x86_64, entry: Treat regs->ax the same in fastpath and slowpath syscalls (diff) | |
| download | kernel-1dcf74f6edfc3a9acd84d83d8865dd9e2a3b1d1e.tar.gz kernel-1dcf74f6edfc3a9acd84d83d8865dd9e2a3b1d1e.zip | |
x86_64, entry: Use split-phase syscall_trace_enter for 64-bit syscalls
On KVM on my box, this reduces the overhead from an always-accept
seccomp filter from ~130ns to ~17ns. Most of that comes from
avoiding IRET on every syscall when seccomp is enabled.
In extremely approximate hacked-up benchmarking, just bypassing IRET
saves about 80ns, so there's another 43ns of savings here from
simplifying the seccomp path.
The diffstat is also rather nice :)
Signed-off-by: Andy Lutomirski <[email protected]>
Link: http://lkml.kernel.org/r/a3dbd267ee990110478d349f78cccfdac5497a84.1409954077.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python/check-perf-trace.py')
0 files changed, 0 insertions, 0 deletions