From 21d65555cd878c8d6ff2b2902e6c16b2ca73f33d Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 14 Mar 2019 09:57:57 +0100 Subject: [PATCH] perf/x86: Simplify x86_pmu.get_constraints() interface There is a special case for validate_events() where we'll call x86_pmu.get_constraints(.idx=-1). It's purpose, up until recent, seems to be to avoid taking a previous constraint from cpuc->event_constraint[] in intel_get_event_constraints(). (I could not find any other get_event_constraints() implementation using @idx) However, since that cpuc is freshly allocated, that array will in fact be initialized with NULL pointers, achieving the very same effect. Therefore remove this exception. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Stephane Eranian Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Vince Weaver Signed-off-by: Ingo Molnar --- arch/x86/events/core.c | 2 +- arch/x86/events/intel/core.c | 8 +++----- 2 files changed, 4 insertions(+), 6 deletions(-) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index e2b1447..508bf53 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -2031,7 +2031,7 @@ static int validate_event(struct perf_event *event) if (IS_ERR(fake_cpuc)) return PTR_ERR(fake_cpuc); - c = x86_pmu.get_event_constraints(fake_cpuc, -1, event); + c = x86_pmu.get_event_constraints(fake_cpuc, 0, event); if (!c || !c->weight) ret = -EINVAL; diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index dee281d..879ab54 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2931,11 +2931,9 @@ static struct event_constraint * intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx, struct perf_event *event) { - struct event_constraint *c1 = NULL; - struct event_constraint *c2; + struct event_constraint *c1, *c2; - if (idx >= 0) /* fake does < 0 */ - c1 = cpuc->event_constraint[idx]; + c1 = cpuc->event_constraint[idx]; /* * first time only @@ -3410,7 +3408,7 @@ tfa_get_event_constraints(struct cpu_hw_events *cpuc, int idx, /* * Without TFA we must not use PMC3. */ - if (!allow_tsx_force_abort && test_bit(3, c->idxmsk) && idx >= 0) { + if (!allow_tsx_force_abort && test_bit(3, c->idxmsk)) { c = dyn_constraint(cpuc, c, idx); c->idxmsk64 &= ~(1ULL << 3); c->weight--; -- 2.7.4