Re: [PATCH] oprofile, x86: Fix race in nmi handler while starting

[Ingo Molnar]

* Robert Richter <robert.richter@xxxxxxx> wrote:

> In some rare cases, nmis are generated immediately after the nmi 
> handler of the cpu was started. This causes the counter not to be 
> enabled. Before enabling the nmi handlers we need to set variable 
> ctr_running first and make sure its value is written to memory.
> 
> Also, the patch makes all existing barriers a memory barrier 
> instead of a compiler barrier only.

Could we *PLEASE* just do the obvious and turn oprofile into a perf 
user on x86 too, like ARM already does? Two years down the line and 
there's zero progress in that area. We want to obsolete the Oprofile 
PMU bits on x86, the infrastructure duplication causes non-trivial 
problems like this one.

Thanks,

	Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/