linux-kernel - Re: [patch] perf_events: more wrong events for AMD fam10h

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1309173740.6701.103.camel@twins>
Date:	Mon, 27 Jun 2011 13:22:20 +0200
From:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
To:	Vince Weaver <vweaver1@...s.utk.edu>
Cc:	linux-kernel@...r.kernel.org, Paul Mackerras <paulus@...ba.org>,
	Ingo Molnar <mingo@...e.hu>,
	Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
	Stephane Eranian <eranian@...gle.com>,
	Robert Richter <robert.richter@....com>
Subject: Re: [patch] perf_events: more wrong events for AMD fam10h

On Tue, 2011-06-07 at 15:39 -0400, Vince Weaver wrote:
> Hello
> 
> I'm in the process of auditing perf_event's awesome "generalized events".
> 
> On AMD fam10h for some we have the following definitions:
>   cache-references = INSTRUCTION_CACHE_FETCHES	0x530080
>   cache-misses 	   = INSTRUCTION_CACHE_MISSES	0x530081
> 
> on Intel at least I'm pretty sure these events match to Last Level Cache 
> accesses/misses, not icache.  Is there a reason for this?
> 
> Attached is a patch that removes these until better events can be found.
> (LLC is tricky on AMD as it's a shared resource).
> 
> Note, l1-dcache-stores is broken too, I'm looking into it.
> 
> Thanks,
> 
> Vince
> vweaver1@...s.utk.edu
> 
> diff --git a/arch/x86/kernel/cpu/perf_event_amd.c b/arch/x86/kernel/cpu/perf_event_amd.c
> index fe29c1d..a46b987 100644
> --- a/arch/x86/kernel/cpu/perf_event_amd.c
> +++ b/arch/x86/kernel/cpu/perf_event_amd.c
> @@ -98,8 +98,6 @@ static const u64 amd_perfmon_event_map[] =
>  {
>    [PERF_COUNT_HW_CPU_CYCLES]			= 0x0076,
>    [PERF_COUNT_HW_INSTRUCTIONS]			= 0x00c0,
> -  [PERF_COUNT_HW_CACHE_REFERENCES]		= 0x0080,
> -  [PERF_COUNT_HW_CACHE_MISSES]			= 0x0081,

Would 0x40000F7E0 and 0x40000F7E1 be better?

>    [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]		= 0x00c2,
>    [PERF_COUNT_HW_BRANCH_MISSES]			= 0x00c3,
>    [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= 0x00d0, /* "Decoder empty" event */

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