[tip:perf/core] perf/x86/intel: Clean-up/reduce PEBS code

From: tip-bot for Peter Zijlstra
Date: Thu Sep 12 2013 - 14:10:15 EST


Commit-ID: d2beea4a3419e63804094e9ac4b6d1518bc17a9b
Gitweb: http://git.kernel.org/tip/d2beea4a3419e63804094e9ac4b6d1518bc17a9b
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Thu, 12 Sep 2013 13:00:47 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 12 Sep 2013 19:13:37 +0200

perf/x86/intel: Clean-up/reduce PEBS code

Get rid of some pointless duplication introduced by the Haswell code.

Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-8q6y4davda9aawwv5yxe7klp@xxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/kernel/cpu/perf_event_intel_ds.c | 94 +++++++++----------------------
1 file changed, 26 insertions(+), 68 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 104cbba..f364c13 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -188,8 +188,7 @@ struct pebs_record_hsw {
u64 r8, r9, r10, r11;
u64 r12, r13, r14, r15;
u64 status, dla, dse, lat;
- u64 real_ip; /* the actual eventing ip */
- u64 tsx_tuning; /* TSX abort cycles and flags */
+ u64 real_ip, tsx_tuning;
};

union hsw_tsx_tuning {
@@ -811,10 +810,8 @@ static void __intel_pmu_pebs_event(struct perf_event *event,
struct pt_regs *iregs, void *__pebs)
{
/*
- * We cast to pebs_record_nhm to get the load latency data
- * if extra_reg MSR_PEBS_LD_LAT_THRESHOLD used
- * We cast to the biggest PEBS record are careful not
- * to access out-of-bounds members.
+ * We cast to the biggest pebs_record but are careful not to
+ * unconditionally access the 'extra' entries.
*/
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct pebs_record_hsw *pebs = __pebs;
@@ -884,12 +881,11 @@ static void __intel_pmu_pebs_event(struct perf_event *event,
regs.flags &= ~PERF_EFLAGS_EXACT;

if ((event->attr.sample_type & PERF_SAMPLE_ADDR) &&
- x86_pmu.intel_cap.pebs_format >= 1)
+ x86_pmu.intel_cap.pebs_format >= 1)
data.addr = pebs->dla;

/* Only set the TSX weight when no memory weight was requested. */
- if ((event->attr.sample_type & PERF_SAMPLE_WEIGHT) &&
- !fll &&
+ if ((event->attr.sample_type & PERF_SAMPLE_WEIGHT) && !fll &&
(x86_pmu.intel_cap.pebs_format >= 2))
data.weight = intel_hsw_weight(pebs);

@@ -941,17 +937,34 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
__intel_pmu_pebs_event(event, iregs, at);
}

-static void __intel_pmu_drain_pebs_nhm(struct pt_regs *iregs, void *at,
- void *top)
+static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct debug_store *ds = cpuc->ds;
struct perf_event *event = NULL;
+ void *at, *top;
u64 status = 0;
- int bit;
+ int bit, n;
+
+ if (!x86_pmu.pebs_active)
+ return;
+
+ at = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
+ top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;

ds->pebs_index = ds->pebs_buffer_base;

+ n = (top - at) / x86_pmu.pebs_record_size;
+ if (n <= 0)
+ return;
+
+ /*
+ * Should not happen, we program the threshold at 1 and do not
+ * set a reset value.
+ */
+ WARN_ONCE(n > x86_pmu.max_pebs_events,
+ "Unexpected number of pebs records %d\n", n);
+
for (; at < top; at += x86_pmu.pebs_record_size) {
struct pebs_record_nhm *p = at;

@@ -979,61 +992,6 @@ static void __intel_pmu_drain_pebs_nhm(struct pt_regs *iregs, void *at,
}
}

-static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
-{
- struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
- struct debug_store *ds = cpuc->ds;
- struct pebs_record_nhm *at, *top;
- int n;
-
- if (!x86_pmu.pebs_active)
- return;
-
- at = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
- top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;
-
- ds->pebs_index = ds->pebs_buffer_base;
-
- n = top - at;
- if (n <= 0)
- return;
-
- /*
- * Should not happen, we program the threshold at 1 and do not
- * set a reset value.
- */
- WARN_ONCE(n > x86_pmu.max_pebs_events,
- "Unexpected number of pebs records %d\n", n);
-
- return __intel_pmu_drain_pebs_nhm(iregs, at, top);
-}
-
-static void intel_pmu_drain_pebs_hsw(struct pt_regs *iregs)
-{
- struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
- struct debug_store *ds = cpuc->ds;
- struct pebs_record_hsw *at, *top;
- int n;
-
- if (!x86_pmu.pebs_active)
- return;
-
- at = (struct pebs_record_hsw *)(unsigned long)ds->pebs_buffer_base;
- top = (struct pebs_record_hsw *)(unsigned long)ds->pebs_index;
-
- n = top - at;
- if (n <= 0)
- return;
- /*
- * Should not happen, we program the threshold at 1 and do not
- * set a reset value.
- */
- WARN_ONCE(n > x86_pmu.max_pebs_events,
- "Unexpected number of pebs records %d\n", n);
-
- return __intel_pmu_drain_pebs_nhm(iregs, at, top);
-}
-
/*
* BTS, PEBS probe and setup
*/
@@ -1068,7 +1026,7 @@ void intel_ds_init(void)
case 2:
pr_cont("PEBS fmt2%c, ", pebs_type);
x86_pmu.pebs_record_size = sizeof(struct pebs_record_hsw);
- x86_pmu.drain_pebs = intel_pmu_drain_pebs_hsw;
+ x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
break;

default:
--
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