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Re: [patch 05/10] fs: remove extra lookup in __lookup_hash


Hi, Andi -

On linux-fsdevel, you wrote:

> As a quick experiment I set a systemtap probe for this on my workstation
> 
> global first, second 
> probe kernel.function("*@fs/namei.c:1143") { first++ }  
> probe kernel.function("*@fs/namei.c:1149") { second++ } 
> probe end { printf("first %d, second %d\n", first, second) }  
> 
> and did a quick kernel build, resulting in:
> 
> first 22753, second 22753

This probably isn't doing what you thought.  You probably should have
used kernel.statement() instead of kernel.function().  Plus if you
use stap -t, you wouldn't need those two explicit counters; you'd 
get hit counts/timings for each probe point at script end.

- FChE


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