Re: oprofile BUG() in current kernel.

[Eric D. <da...@co...>]

Gianni Tedesco a écrit :
>
>
> Nope, exact same bad paging request in kernel mode... probably the bug
> is something deep in oprofile then?
>   
Hum... Are you using oprofile as a module or statically included in kernel ?

Current module loader only allocates percpu room by examining 
".data.percpu" section and should be augmented to also look at 
".data.percpu.shared_aligned"
Or, change DEFINE_PER_CPU_SHARED_ALIGNED() for modules (to use 
".data.percpu" only)

Anyway, with the per_cpu conversion of cpu_buffer, we dont need to 
request cache_line alignment anymore

[PATCH] oprofile: Dont request cache line alignment for cpu_buffer

Alignment was previously requested because cpu_buffer was an [NR_CPUS] 
array, to avoid cache line sharing between CPUS.

After commit 608dfddd845da5ab6accef70154c8910529699f7 ( 
oprofile: change cpu_buffer from array to per_cpu variable ),
we dont need to force an alignement anymore since cpu_buffer sits in 
per_cpu zone.

Signed-off-by: Eric Dumazet <da...@co...>