perf/x86: Honor the architectural performance monitoring version
authorPalik, Imre <imrep@amazon.de>
Mon, 8 Jun 2015 12:46:49 +0000 (14:46 +0200)
committerSasha Levin <sasha.levin@oracle.com>
Mon, 13 Jul 2015 12:50:09 +0000 (08:50 -0400)
commit71e331989c7b5bdf5b910d718ce206f431323039
tree674948f7563c1fe254069d1334ebb5140400ffdc
parenteb1ea7225f048971e596f26dbda4f7089869b553
perf/x86: Honor the architectural performance monitoring version

[ Upstream commit 2c33645d366d13b969d936b68b9f4875b1fdddea ]

Architectural performance monitoring, version 1, doesn't support fixed counters.

Currently, even if a hypervisor advertises support for architectural
performance monitoring version 1, perf may still try to use the fixed
counters, as the constraints are set up based on the CPU model.

This patch ensures that perf honors the architectural performance monitoring
version returned by CPUID, and it only uses the fixed counters for version 2
and above.

(Some of the ideas in this patch came from Peter Zijlstra.)

Signed-off-by: Imre Palik <imrep@amazon.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Anthony Liguori <aliguori@amazon.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1433767609-1039-1-git-send-email-imrep.amz@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
arch/x86/kernel/cpu/perf_event_intel.c