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Commit 86a04461 authored by Andi Kleen's avatar Andi Kleen Committed by Ingo Molnar
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perf/x86: Revamp PEBS event selection



The basic idea is that it does not make sense to list all PEBS
events individually. The list is very long, sometimes outdated
and the hardware doesn't need it. If an event does not support
PEBS it will just not count, there is no security issue.

We need to only list events that something special, like
supporting load or store addresses.

This vastly simplifies the PEBS event selection. It also
speeds up the scheduling because the scheduler doesn't
have to walk as many constraints.

Bugs fixed:

 - We do not allow setting forbidden flags with PEBS anymore
   (SDM 18.9.4), except for the special cycle event.
   This is done using a new constraint macro that also
   matches on the event flags.

 - Correct DataLA and load/store/na flags reporting on Haswell
   [Requires a followon patch]

 - We did not allow all PEBS events on Haswell:
   We were missing some valid subevents in d1-d2 (MEM_LOAD_UOPS_RETIRED.*,
   MEM_LOAD_UOPS_RETIRED_L3_HIT_RETIRED.*)

This includes the changes proposed by Stephane earlier and obsoletes
his patchkit (except for some changes on pre Sandy Bridge/Silvermont
CPUs)

I only did Sandy Bridge and Silvermont and later so far, mostly because these
are the parts I could directly confirm the hardware behavior with hardware
architects. Also I do not believe the older CPUs have any
missing events in their PEBS list, so there's no pressing
need to change them.

I did not implement the flag proposed by Peter to allow
setting forbidden flags. If really needed this could
be implemented on to of this patch.

v2: Fix broken store events on SNB/IVB (Stephane Eranian)
v3: More fixes. Rename some arguments (Stephane Eranian)
v4: List most Haswell events individually again to report
memory operation type correctly.
Add new flags to describe load/store/na for datala.
Update description.

Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
Reviewed-by: default avatarStephane Eranian <eranian@google.com>
Signed-off-by: default avatarPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1407785233-32193-2-git-send-email-eranian@google.com


Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com>
Cc: Mark Davies <junk@eslaf.co.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 03de874a
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