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Subject[PATCH 21/49] perf: Introduce PERF_TYPE_HARDWARE_PMU and PERF_TYPE_HW_CACHE_PMU
Date
From: Kan Liang <kan.liang@linux.intel.com>

Current Hardware events and Hardware cache events have special perf
types, PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE. The two types don't
pass the PMU type in the user interface. For a hybrid system, the perf
subsystem doesn't know which PMU the events belong to. The first capable
PMU will always be assigned to the events. The events never get a chance
to run on the other capable PMUs.

Add a PMU aware version PERF_TYPE_HARDWARE_PMU and
PERF_TYPE_HW_CACHE_PMU. The PMU type ID is stored at attr.config[40:32].
Support the new types for X86.

Suggested-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
---
arch/x86/events/core.c | 10 ++++++++--
include/uapi/linux/perf_event.h | 26 ++++++++++++++++++++++++++
kernel/events/core.c | 14 +++++++++++++-
3 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index b68d38a..c48e37c 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -483,7 +483,7 @@ int x86_setup_perfctr(struct perf_event *event)
if (attr->type == event->pmu->type)
return x86_pmu_extra_regs(event->attr.config, event);

- if (attr->type == PERF_TYPE_HW_CACHE)
+ if ((attr->type == PERF_TYPE_HW_CACHE) || (attr->type == PERF_TYPE_HW_CACHE_PMU))
return set_ext_hw_attr(hwc, event);

if (attr->config >= x86_pmu.max_events)
@@ -2415,9 +2415,15 @@ static int x86_pmu_event_init(struct perf_event *event)

if ((event->attr.type != event->pmu->type) &&
(event->attr.type != PERF_TYPE_HARDWARE) &&
- (event->attr.type != PERF_TYPE_HW_CACHE))
+ (event->attr.type != PERF_TYPE_HW_CACHE) &&
+ (event->attr.type != PERF_TYPE_HARDWARE_PMU) &&
+ (event->attr.type != PERF_TYPE_HW_CACHE_PMU))
return -ENOENT;

+ if ((event->attr.type == PERF_TYPE_HARDWARE_PMU) ||
+ (event->attr.type == PERF_TYPE_HW_CACHE_PMU))
+ event->attr.config &= PERF_HW_CACHE_EVENT_MASK;
+
if (IS_X86_HYBRID && (event->cpu != -1)) {
hybrid_pmu = container_of(event->pmu, struct x86_hybrid_pmu, pmu);
if (!cpumask_test_cpu(event->cpu, &hybrid_pmu->supported_cpus))
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 7d292de5..83ab6a6 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -33,6 +33,8 @@ enum perf_type_id {
PERF_TYPE_HW_CACHE = 3,
PERF_TYPE_RAW = 4,
PERF_TYPE_BREAKPOINT = 5,
+ PERF_TYPE_HARDWARE_PMU = 6,
+ PERF_TYPE_HW_CACHE_PMU = 7,

PERF_TYPE_MAX, /* non-ABI */
};
@@ -95,6 +97,30 @@ enum perf_hw_cache_op_result_id {
};

/*
+ * attr.config layout for type PERF_TYPE_HARDWARE* and PERF_TYPE_HW_CACHE*
+ * PERF_TYPE_HARDWARE: 0xAA
+ * AA: hardware event ID
+ * PERF_TYPE_HW_CACHE: 0xCCBBAA
+ * AA: hardware cache ID
+ * BB: hardware cache op ID
+ * CC: hardware cache op result ID
+ * PERF_TYPE_HARDWARE_PMU: 0xDD000000AA
+ * AA: hardware event ID
+ * DD: PMU type ID
+ * PERF_TYPE_HW_CACHE_PMU: 0xDD00CCBBAA
+ * AA: hardware cache ID
+ * BB: hardware cache op ID
+ * CC: hardware cache op result ID
+ * DD: PMU type ID
+ */
+#define PERF_HW_CACHE_ID_SHIFT 0
+#define PERF_HW_CACHE_OP_ID_SHIFT 8
+#define PERF_HW_CACHE_OP_RESULT_ID_SHIFT 16
+#define PERF_HW_CACHE_EVENT_MASK 0xffffff
+
+#define PERF_PMU_TYPE_SHIFT 32
+
+/*
* Special "software" events provided by the kernel, even if the hardware
* does not support performance events. These events measure various
* physical and sw events of the kernel (and allow the profiling of them as
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 5206097..04465b2 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -11052,6 +11052,14 @@ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event)
return ret;
}

+static bool perf_event_is_hw_pmu_type(struct perf_event *event)
+{
+ int type = event->attr.type;
+
+ return type == PERF_TYPE_HARDWARE_PMU ||
+ type == PERF_TYPE_HW_CACHE_PMU;
+}
+
static struct pmu *perf_init_event(struct perf_event *event)
{
int idx, type, ret;
@@ -11075,13 +11083,17 @@ static struct pmu *perf_init_event(struct perf_event *event)
if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE)
type = PERF_TYPE_RAW;

+ if (perf_event_is_hw_pmu_type(event))
+ type = event->attr.config >> PERF_PMU_TYPE_SHIFT;
+
again:
rcu_read_lock();
pmu = idr_find(&pmu_idr, type);
rcu_read_unlock();
if (pmu) {
ret = perf_try_init_event(pmu, event);
- if (ret == -ENOENT && event->attr.type != type) {
+ if (ret == -ENOENT && event->attr.type != type &&
+ !perf_event_is_hw_pmu_type(event)) {
type = event->attr.type;
goto again;
}
--
2.7.4
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