Commit-ID: 97e7e4f391cac2b00417b581b432533d245d4fd0 Gitweb: http://git.kernel.org/tip/97e7e4f391cac2b00417b581b432533d245d4fd0 Author: Witold Baryluk <baryluk@xxxxxxxxxxxxxxxx> AuthorDate: Tue, 17 Mar 2009 21:15:44 +0100 Commit: Steven Rostedt <srostedt@xxxxxxxxxx> CommitDate: Tue, 17 Mar 2009 23:10:43 -0400 tracing: optimization of branch tracer Impact: better performance for if branch tracer Use an array to count the hit and misses of a conditional instead of using another conditional. This cuts down on saturation of branch predictions and increases performance of modern pipelined architectures. Signed-off-by: Witold Baryluk <baryluk@xxxxxxxxxxxxxxxx> Signed-off-by: Steven Rostedt <srostedt@xxxxxxxxxx> --- include/linux/compiler.h | 6 ++---- 1 files changed, 2 insertions(+), 4 deletions(-) diff --git a/include/linux/compiler.h b/include/linux/compiler.h index d95da10..6faa7e5 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -68,6 +68,7 @@ struct ftrace_branch_data { unsigned long miss; unsigned long hit; }; + unsigned long miss_hit[2]; }; }; @@ -125,10 +126,7 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); .line = __LINE__, \ }; \ ______r = !!(cond); \ - if (______r) \ - ______f.hit++; \ - else \ - ______f.miss++; \ + ______f.miss_hit[______r]++; \ ______r; \ })) #endif /* CONFIG_PROFILE_ALL_BRANCHES */ -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html