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Date: Mon, 11 Nov 2019 19:28:58 +0100
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org, Kim Phillips <kim.phillips@....com>,
"Peter Zijlstra (Intel)" <peterz@...radead.org>,
Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
Arnaldo Carvalho de Melo <acme@...nel.org>,
Arnaldo Carvalho de Melo <acme@...hat.com>,
Borislav Petkov <bp@...en8.de>,
"H. Peter Anvin" <hpa@...or.com>, Jiri Olsa <jolsa@...hat.com>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Mark Rutland <mark.rutland@....com>,
Namhyung Kim <namhyung@...nel.org>,
Stephane Eranian <eranian@...gle.com>,
Thomas Gleixner <tglx@...utronix.de>,
Vince Weaver <vincent.weaver@...ne.edu>,
Ingo Molnar <mingo@...nel.org>, Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.14 088/105] perf/x86/amd/ibs: Handle erratum #420 only on the affected CPU family (10h)
From: Kim Phillips <kim.phillips@....com>
[ Upstream commit e431e79b60603079d269e0c2a5177943b95fa4b6 ]
This saves us writing the IBS control MSR twice when disabling the
event.
I searched revision guides for all families since 10h, and did not
find occurrence of erratum #420, nor anything remotely similar:
so we isolate the secondary MSR write to family 10h only.
Also unconditionally update the count mask for IBS Op implementations
that have read & writeable current count (CurCnt) fields in addition
to the MaxCnt field. These bits were reserved on prior
implementations, and therefore shouldn't have negative impact.
Signed-off-by: Kim Phillips <kim.phillips@....com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
Cc: Alexander Shishkin <alexander.shishkin@...ux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@...nel.org>
Cc: Arnaldo Carvalho de Melo <acme@...hat.com>
Cc: Borislav Petkov <bp@...en8.de>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Jiri Olsa <jolsa@...hat.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Mark Rutland <mark.rutland@....com>
Cc: Namhyung Kim <namhyung@...nel.org>
Cc: Stephane Eranian <eranian@...gle.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Vince Weaver <vincent.weaver@...ne.edu>
Fixes: c9574fe0bdb9 ("perf/x86-ibs: Implement workaround for IBS erratum #420")
Link: https://lkml.kernel.org/r/20191023150955.30292-2-kim.phillips@amd.com
Signed-off-by: Ingo Molnar <mingo@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
arch/x86/events/amd/ibs.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c
index 4deecdb26ab30..f24e9adaa3167 100644
--- a/arch/x86/events/amd/ibs.c
+++ b/arch/x86/events/amd/ibs.c
@@ -389,7 +389,8 @@ static inline void perf_ibs_disable_event(struct perf_ibs *perf_ibs,
struct hw_perf_event *hwc, u64 config)
{
config &= ~perf_ibs->cnt_mask;
- wrmsrl(hwc->config_base, config);
+ if (boot_cpu_data.x86 == 0x10)
+ wrmsrl(hwc->config_base, config);
config &= ~perf_ibs->enable_mask;
wrmsrl(hwc->config_base, config);
}
@@ -564,7 +565,8 @@ static struct perf_ibs perf_ibs_op = {
},
.msr = MSR_AMD64_IBSOPCTL,
.config_mask = IBS_OP_CONFIG_MASK,
- .cnt_mask = IBS_OP_MAX_CNT,
+ .cnt_mask = IBS_OP_MAX_CNT | IBS_OP_CUR_CNT |
+ IBS_OP_CUR_CNT_RAND,
.enable_mask = IBS_OP_ENABLE,
.valid_mask = IBS_OP_VAL,
.max_period = IBS_OP_MAX_CNT << 4,
--
2.20.1
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