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Subject[PATCH] perf,x86: add constraint for IVB CYCLE_ACTIVITY:CYCLES_LDM_PENDING

The IvyBridge event CYCLE_ACTIVITY:CYCLES_LDM_PENDING can only
be measured on counters 0-3 when HT is off. When HT is on, you
only have counters 0-3.

If you program it on the eight counters for 1s on a 3GHz
IVB laptop running a noploop, you see:

2 747 527 CYCLE_ACTIVITY:CYCLES_LDM_PENDING
2 747 527 CYCLE_ACTIVITY:CYCLES_LDM_PENDING
2 747 527 CYCLE_ACTIVITY:CYCLES_LDM_PENDING
2 747 527 CYCLE_ACTIVITY:CYCLES_LDM_PENDING
3 280 563 608 CYCLE_ACTIVITY:CYCLES_LDM_PENDING
3 280 563 608 CYCLE_ACTIVITY:CYCLES_LDM_PENDING
3 280 563 608 CYCLE_ACTIVITY:CYCLES_LDM_PENDING
3 280 563 608 CYCLE_ACTIVITY:CYCLES_LDM_PENDING

Clearly the last 4 values are bogus.

Signed-off-by: Stephane Eranian <eranian@google.com>
---
arch/x86/kernel/cpu/perf_event_intel.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index 0abf674..c62d883 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -124,6 +124,7 @@ static struct event_constraint intel_ivb_event_constraints[] __read_mostly =
INTEL_UEVENT_CONSTRAINT(0x0148, 0x4), /* L1D_PEND_MISS.PENDING */
INTEL_UEVENT_CONSTRAINT(0x0279, 0xf), /* IDQ.EMTPY */
INTEL_UEVENT_CONSTRAINT(0x019c, 0xf), /* IDQ_UOPS_NOT_DELIVERED.CORE */
+ INTEL_UEVENT_CONSTRAINT(0x02a3, 0xf), /* CYCLE_ACTIVITY.CYCLES_LDM_PENDING */
INTEL_UEVENT_CONSTRAINT(0x04a3, 0xf), /* CYCLE_ACTIVITY.CYCLES_NO_EXECUTE */
INTEL_UEVENT_CONSTRAINT(0x05a3, 0xf), /* CYCLE_ACTIVITY.STALLS_L2_PENDING */
INTEL_UEVENT_CONSTRAINT(0x06a3, 0xf), /* CYCLE_ACTIVITY.STALLS_LDM_PENDING */
--
1.8.4


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