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perf/x86/amd/ibs: Fix raw sample data accumulation 

commit 36e1be8ada upstream.

Neither IbsBrTarget nor OPDATA4 are populated in IBS Fetch mode.
Don't accumulate them into raw sample user data in that case.

Also, in Fetch mode, add saving the IBS Fetch Control Extended MSR.

Technically, there is an ABI change here with respect to the IBS raw
sample data format, but I don't see any perf driver version information
being included in perf.data file headers, but, existing users can detect
whether the size of the sample record has reduced by 8 bytes to
determine whether the IBS driver has this fix.

Fixes: 904cb3677f ("perf/x86/amd/ibs: Update IBS MSRs and feature definitions")
Reported-by: Stephane Eranian <stephane.eranian@google.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200908214740.18097-6-kim.phillips@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5.4-rM2-2.2.x-imx-squashed
Kim Phillips 2020-09-08 16:47:38 -05:00 committed by Greg Kroah-Hartman
parent 2e2a324641
commit d789e1c5b1
2 changed files with 17 additions and 10 deletions
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26
arch/x86/events/amd/ibs.c
View File

@ -636,18 +636,24 @@ fail:
perf_ibs->offset_max,
offset + 1);
} while (offset < offset_max);
/*
* Read IbsBrTarget, IbsOpData4, and IbsExtdCtl separately
* depending on their availability.
* Can't add to offset_max as they are staggered
*/
if (event->attr.sample_type & PERF_SAMPLE_RAW) {
/*
* Read IbsBrTarget and IbsOpData4 separately
* depending on their availability.
* Can't add to offset_max as they are staggered
*/
if (ibs_caps & IBS_CAPS_BRNTRGT) {
rdmsrl(MSR_AMD64_IBSBRTARGET, *buf++);
size++;
if (perf_ibs == &perf_ibs_op) {
if (ibs_caps & IBS_CAPS_BRNTRGT) {
rdmsrl(MSR_AMD64_IBSBRTARGET, *buf++);
size++;
}
if (ibs_caps & IBS_CAPS_OPDATA4) {
rdmsrl(MSR_AMD64_IBSOPDATA4, *buf++);
size++;
}
}
if (ibs_caps & IBS_CAPS_OPDATA4) {
rdmsrl(MSR_AMD64_IBSOPDATA4, *buf++);
if (perf_ibs == &perf_ibs_fetch && (ibs_caps & IBS_CAPS_FETCHCTLEXTD)) {
rdmsrl(MSR_AMD64_ICIBSEXTDCTL, *buf++);
size++;
}
}

1
arch/x86/include/asm/msr-index.h
View File

@ -432,6 +432,7 @@
#define MSR_AMD64_IBSOP_REG_MASK ((1UL<<MSR_AMD64_IBSOP_REG_COUNT)-1)
#define MSR_AMD64_IBSCTL 0xc001103a
#define MSR_AMD64_IBSBRTARGET 0xc001103b
#define MSR_AMD64_ICIBSEXTDCTL 0xc001103c
#define MSR_AMD64_IBSOPDATA4 0xc001103d
#define MSR_AMD64_IBS_REG_COUNT_MAX 8 /* includes MSR_AMD64_IBSBRTARGET */
#define MSR_AMD64_SEV 0xc0010131