[tip:perf/core] perf/x86/intel: Export mem events only if there's PEBS support
From: tip-bot for Jiri Olsa
Date: Tue Oct 16 2018 - 12:04:43 EST
Commit-ID: d4ae552982de39417d17f823df1f06b1cbc3686c
Gitweb: https://git.kernel.org/tip/d4ae552982de39417d17f823df1f06b1cbc3686c
Author: Jiri Olsa <jolsa@xxxxxxxxxx>
AuthorDate: Thu, 6 Sep 2018 15:57:48 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 16 Oct 2018 17:29:07 +0200
perf/x86/intel: Export mem events only if there's PEBS support
Memory events depends on PEBS support and access to LDLAT MSR, but we
display them in /sys/devices/cpu/events even if the CPU does not
provide those, like for KVM guests.
That brings the false assumption that those events should be
available, while they fail event to open.
Separating the mem-* events attributes and merging them with
cpu_events only if there's PEBS support detected.
We could also check if LDLAT MSR is available, but the PEBS check
seems to cover the need now.
Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Michael Petlan <mpetlan@xxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vince Weaver <vincent.weaver@xxxxxxxxx>
Link: http://lkml.kernel.org/r/20180906135748.GC9577@krava
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/events/core.c | 8 ++---
arch/x86/events/intel/core.c | 69 +++++++++++++++++++++++++++++++++-----------
2 files changed, 56 insertions(+), 21 deletions(-)
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 06b708494898..de32741d041a 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -1652,9 +1652,9 @@ __init struct attribute **merge_attr(struct attribute **a, struct attribute **b)
struct attribute **new;
int j, i;
- for (j = 0; a[j]; j++)
+ for (j = 0; a && a[j]; j++)
;
- for (i = 0; b[i]; i++)
+ for (i = 0; b && b[i]; i++)
j++;
j++;
@@ -1663,9 +1663,9 @@ __init struct attribute **merge_attr(struct attribute **a, struct attribute **b)
return NULL;
j = 0;
- for (i = 0; a[i]; i++)
+ for (i = 0; a && a[i]; i++)
new[j++] = a[i];
- for (i = 0; b[i]; i++)
+ for (i = 0; b && b[i]; i++)
new[j++] = b[i];
new[j] = NULL;
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index ab01ef9ddd77..0fb8659b20d8 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -242,7 +242,7 @@ EVENT_ATTR_STR(mem-loads, mem_ld_nhm, "event=0x0b,umask=0x10,ldlat=3");
EVENT_ATTR_STR(mem-loads, mem_ld_snb, "event=0xcd,umask=0x1,ldlat=3");
EVENT_ATTR_STR(mem-stores, mem_st_snb, "event=0xcd,umask=0x2");
-static struct attribute *nhm_events_attrs[] = {
+static struct attribute *nhm_mem_events_attrs[] = {
EVENT_PTR(mem_ld_nhm),
NULL,
};
@@ -278,8 +278,6 @@ EVENT_ATTR_STR_HT(topdown-recovery-bubbles.scale, td_recovery_bubbles_scale,
"4", "2");
static struct attribute *snb_events_attrs[] = {
- EVENT_PTR(mem_ld_snb),
- EVENT_PTR(mem_st_snb),
EVENT_PTR(td_slots_issued),
EVENT_PTR(td_slots_retired),
EVENT_PTR(td_fetch_bubbles),
@@ -290,6 +288,12 @@ static struct attribute *snb_events_attrs[] = {
NULL,
};
+static struct attribute *snb_mem_events_attrs[] = {
+ EVENT_PTR(mem_ld_snb),
+ EVENT_PTR(mem_st_snb),
+ NULL,
+};
+
static struct event_constraint intel_hsw_event_constraints[] = {
FIXED_EVENT_CONSTRAINT(0x00c0, 0), /* INST_RETIRED.ANY */
FIXED_EVENT_CONSTRAINT(0x003c, 1), /* CPU_CLK_UNHALTED.CORE */
@@ -3912,8 +3916,6 @@ EVENT_ATTR_STR(cycles-t, cycles_t, "event=0x3c,in_tx=1");
EVENT_ATTR_STR(cycles-ct, cycles_ct, "event=0x3c,in_tx=1,in_tx_cp=1");
static struct attribute *hsw_events_attrs[] = {
- EVENT_PTR(mem_ld_hsw),
- EVENT_PTR(mem_st_hsw),
EVENT_PTR(td_slots_issued),
EVENT_PTR(td_slots_retired),
EVENT_PTR(td_fetch_bubbles),
@@ -3924,6 +3926,12 @@ static struct attribute *hsw_events_attrs[] = {
NULL
};
+static struct attribute *hsw_mem_events_attrs[] = {
+ EVENT_PTR(mem_ld_hsw),
+ EVENT_PTR(mem_st_hsw),
+ NULL,
+};
+
static struct attribute *hsw_tsx_events_attrs[] = {
EVENT_PTR(tx_start),
EVENT_PTR(tx_commit),
@@ -3940,13 +3948,6 @@ static struct attribute *hsw_tsx_events_attrs[] = {
NULL
};
-static __init struct attribute **get_hsw_events_attrs(void)
-{
- return boot_cpu_has(X86_FEATURE_RTM) ?
- merge_attr(hsw_events_attrs, hsw_tsx_events_attrs) :
- hsw_events_attrs;
-}
-
static ssize_t freeze_on_smi_show(struct device *cdev,
struct device_attribute *attr,
char *buf)
@@ -4023,9 +4024,32 @@ static struct attribute *intel_pmu_attrs[] = {
NULL,
};
+static __init struct attribute **
+get_events_attrs(struct attribute **base,
+ struct attribute **mem,
+ struct attribute **tsx)
+{
+ struct attribute **attrs = base;
+ struct attribute **old;
+
+ if (mem && x86_pmu.pebs)
+ attrs = merge_attr(attrs, mem);
+
+ if (tsx && boot_cpu_has(X86_FEATURE_RTM)) {
+ old = attrs;
+ attrs = merge_attr(attrs, tsx);
+ if (old != base)
+ kfree(old);
+ }
+
+ return attrs;
+}
+
__init int intel_pmu_init(void)
{
struct attribute **extra_attr = NULL;
+ struct attribute **mem_attr = NULL;
+ struct attribute **tsx_attr = NULL;
struct attribute **to_free = NULL;
union cpuid10_edx edx;
union cpuid10_eax eax;
@@ -4137,7 +4161,7 @@ __init int intel_pmu_init(void)
x86_pmu.enable_all = intel_pmu_nhm_enable_all;
x86_pmu.extra_regs = intel_nehalem_extra_regs;
- x86_pmu.cpu_events = nhm_events_attrs;
+ mem_attr = nhm_mem_events_attrs;
/* UOPS_ISSUED.STALLED_CYCLES */
intel_perfmon_event_map[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] =
@@ -4266,7 +4290,7 @@ __init int intel_pmu_init(void)
x86_pmu.extra_regs = intel_westmere_extra_regs;
x86_pmu.flags |= PMU_FL_HAS_RSP_1;
- x86_pmu.cpu_events = nhm_events_attrs;
+ mem_attr = nhm_mem_events_attrs;
/* UOPS_ISSUED.STALLED_CYCLES */
intel_perfmon_event_map[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] =
@@ -4306,6 +4330,7 @@ __init int intel_pmu_init(void)
x86_pmu.flags |= PMU_FL_NO_HT_SHARING;
x86_pmu.cpu_events = snb_events_attrs;
+ mem_attr = snb_mem_events_attrs;
/* UOPS_ISSUED.ANY,c=1,i=1 to count stall cycles */
intel_perfmon_event_map[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] =
@@ -4346,6 +4371,7 @@ __init int intel_pmu_init(void)
x86_pmu.flags |= PMU_FL_NO_HT_SHARING;
x86_pmu.cpu_events = snb_events_attrs;
+ mem_attr = snb_mem_events_attrs;
/* UOPS_ISSUED.ANY,c=1,i=1 to count stall cycles */
intel_perfmon_event_map[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] =
@@ -4380,10 +4406,12 @@ __init int intel_pmu_init(void)
x86_pmu.hw_config = hsw_hw_config;
x86_pmu.get_event_constraints = hsw_get_event_constraints;
- x86_pmu.cpu_events = get_hsw_events_attrs();
+ x86_pmu.cpu_events = hsw_events_attrs;
x86_pmu.lbr_double_abort = true;
extra_attr = boot_cpu_has(X86_FEATURE_RTM) ?
hsw_format_attr : nhm_format_attr;
+ mem_attr = hsw_mem_events_attrs;
+ tsx_attr = hsw_tsx_events_attrs;
pr_cont("Haswell events, ");
name = "haswell";
break;
@@ -4419,10 +4447,12 @@ __init int intel_pmu_init(void)
x86_pmu.hw_config = hsw_hw_config;
x86_pmu.get_event_constraints = hsw_get_event_constraints;
- x86_pmu.cpu_events = get_hsw_events_attrs();
+ x86_pmu.cpu_events = hsw_events_attrs;
x86_pmu.limit_period = bdw_limit_period;
extra_attr = boot_cpu_has(X86_FEATURE_RTM) ?
hsw_format_attr : nhm_format_attr;
+ mem_attr = hsw_mem_events_attrs;
+ tsx_attr = hsw_tsx_events_attrs;
pr_cont("Broadwell events, ");
name = "broadwell";
break;
@@ -4478,7 +4508,9 @@ __init int intel_pmu_init(void)
hsw_format_attr : nhm_format_attr;
extra_attr = merge_attr(extra_attr, skl_format_attr);
to_free = extra_attr;
- x86_pmu.cpu_events = get_hsw_events_attrs();
+ x86_pmu.cpu_events = hsw_events_attrs;
+ mem_attr = hsw_mem_events_attrs;
+ tsx_attr = hsw_tsx_events_attrs;
intel_pmu_pebs_data_source_skl(
boot_cpu_data.x86_model == INTEL_FAM6_SKYLAKE_X);
pr_cont("Skylake events, ");
@@ -4511,6 +4543,9 @@ __init int intel_pmu_init(void)
WARN_ON(!x86_pmu.format_attrs);
}
+ x86_pmu.cpu_events = get_events_attrs(x86_pmu.cpu_events,
+ mem_attr, tsx_attr);
+
if (x86_pmu.num_counters > INTEL_PMC_MAX_GENERIC) {
WARN(1, KERN_ERR "hw perf events %d > max(%d), clipping!",
x86_pmu.num_counters, INTEL_PMC_MAX_GENERIC);