| Date | Sat, 11 Sep 2021 16:33:52 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH 2/2] scripts: ftrace - move the nop-processing in ftrace_init to compile time |
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On Sat, Sep 11, 2021 at 09:50:43PM +0800, Yinan Liu wrote: > When ftrace is enabled, ftrace_init will consume a period of > time, usually around 15~20ms. Approximately 60% of the time is > consumed by nop-processing. Moving the nop-processing to the > compile time can speed up the kernel boot process. > > performance test: > env: Intel(R) Xeon(R) CPU E5-2682 v4 @ 2.50GHz
If you use objtool's -M argument instead of recordmcount, you already get this and you can avoid running recordmcount entirely.
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