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Commit 1ac7fd81 authored by Peter Zijlstra (Intel)'s avatar Peter Zijlstra (Intel) Committed by Peter Zijlstra
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perf/x86/intel/lbr: Support LBR format V7



The Goldmont plus and Tremont have LBR format V7. The V7 has LBR_INFO,
which is the same as LBR format V5. But V7 doesn't support TSX.

Without the patch, the associated misprediction and cycles information
in the LBR_INFO may be lost on a Goldmont plus platform.
For Tremont, the patch only impacts the non-PEBS events. Because of the
adaptive PEBS, the LBR_INFO is always processed for a PEBS event.

Currently, two different ways are used to check the LBR capabilities,
which make the codes complex and confusing.
For the LBR format V4 and earlier, the global static lbr_desc array is
used to store the flags for the LBR capabilities in each LBR format.
For LBR format V5 and V6, the current code checks the version number
for the LBR capabilities.

There are common LBR capabilities among LBR format versions. Several
flags for the LBR capabilities are introduced into the struct x86_pmu.
The flags, which can be shared among LBR formats, are used to check
the LBR capabilities. Add intel_pmu_lbr_init() to set the flags
accordingly at boot time.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: default avatarKan Liang <kan.liang@linux.intel.com>
Link: https://lkml.kernel.org/r/1641315077-96661-1-git-send-email-peterz@infradead.org
parent 0036fb00
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