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| author | Kim Phillips <kim.phillips@amd.com> | 2020-09-09 00:47:39 +0300 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2020-09-10 12:19:36 +0300 |
| commit | 8b0bed7d410f48499d72af2e2bcd890daad94e0d (patch) | |
| tree | fe71f8689e38691caba515131ba4f43ed28a9372 /arch/x86/include/asm | |
| parent | 36e1be8ada994d509538b3b1d0af8b63c351e729 (diff) | |
| download | linux-8b0bed7d410f48499d72af2e2bcd890daad94e0d.tar.xz | |
perf/x86/amd/ibs: Support 27-bit extended Op/cycle counter
IBS hardware with the OpCntExt feature gets a 7-bit wider internal
counter. Both the maximum and current count bitfields in the
IBS_OP_CTL register are extended to support reading and writing it.
No changes are necessary to the driver for handling the extra
contiguous current count bits (IbsOpCurCnt), as the driver already
passes through 32 bits of that field. However, the driver has to do
some extra bit manipulation when converting from a period to the
non-contiguous (although conveniently aligned) extra bits in the
IbsOpMaxCnt bitfield.
This decreases IBS Op interrupt overhead when the period is over
1,048,560 (0xffff0), which would previously activate the driver's
software counter. That threshold is now 134,217,712 (0x7fffff0).
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200908214740.18097-7-kim.phillips@amd.com
Diffstat (limited to 'arch/x86/include/asm')
| -rw-r--r-- | arch/x86/include/asm/perf_event.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index e20aa588dc47..6960cd6d1f23 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -405,6 +405,7 @@ struct pebs_xmm { #define IBS_OP_ENABLE (1ULL<<17) #define IBS_OP_MAX_CNT 0x0000FFFFULL #define IBS_OP_MAX_CNT_EXT 0x007FFFFFULL /* not a register bit mask */ +#define IBS_OP_MAX_CNT_EXT_MASK (0x7FULL<<20) /* separate upper 7 bits */ #define IBS_RIP_INVALID (1ULL<<38) #ifdef CONFIG_X86_LOCAL_APIC |