[tip:perfcounters/core] perf_counter: Implement generalized cache event types

tip-bot for Ingo Molnar
2009-06-06T11:16:51Z

Commit-ID: 8326f44da090d6d304d29b9fdc7fb3e20889e329
Gitweb: http://git.kernel.org/tip/8326f44da090d6d304d29b9fdc7fb3e20889e329
Author: Ingo Molnar <mingo@elte.hu>
AuthorDate: Fri, 5 Jun 2009 20:22:46 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Sat, 6 Jun 2009 13:14:47 +0200

perf_counter: Implement generalized cache event types

Extend generic event enumeration with the PERF_TYPE_HW_CACHE
method.

This is a 3-dimensional space:

{ L1-D, L1-I, L2, ITLB, DTLB, BPU } x
{ load, store, prefetch } x
{ accesses, misses }

User-space passes in the 3 coordinates and the kernel provides
a counter. (if the hardware supports that type and if the
combination makes sense.)

Combinations that make no sense produce a -EINVAL.
Combinations that are not supported by the hardware produce -ENOTSUP.

Extend the tools to deal with this, and rewrite the event symbol
parsing code with various popular aliases for the units and
access methods above. So 'l1-cache-miss' and 'l1d-read-ops' are
both valid aliases.

( x86 is supported for now, with the Nehalem event table filled in,
and with Core2 and Atom having placeholder tables. )

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
Documentation/perf_counter/util/parse-events.c | 104 ++++++++++++-
arch/x86/kernel/cpu/perf_counter.c | 201 +++++++++++++++++++++++-
include/linux/perf_counter.h | 34 ++++
kernel/perf_counter.c | 1 +
4 files changed, 329 insertions(+), 11 deletions(-)

diff --git a/Documentation/perf_counter/util/parse-events.c b/Documentation/perf_counter/util/parse-events.c
index eb56bd9..de9a77c 100644
--- a/Documentation/perf_counter/util/parse-events.c
+++ b/Documentation/perf_counter/util/parse-events.c
@@ -6,6 +6,8 @@
#include "exec_cmd.h"
#include "string.h"

+extern char *strcasestr(const char *haystack, const char *needle);
+
int nr_counters;

struct perf_counter_attr attrs[MAX_COUNTERS];
@@ -17,6 +19,7 @@ struct event_symbol {
};

#define C(x, y) .type = PERF_TYPE_##x, .config = PERF_COUNT_##y
+#define CR(x, y) .type = PERF_TYPE_##x, .config = y

static struct event_symbol event_symbols[] = {
{ C(HARDWARE, CPU_CYCLES), "cpu-cycles", },
@@ -69,6 +72,28 @@ static char *sw_event_names[] = {
"major faults",
};

+#define MAX_ALIASES 8
+
+static char *hw_cache [][MAX_ALIASES] = {
+ { "l1-d" , "l1d" , "l1", "l1-data-cache" },
+ { "l1-i" , "l1i" , "l1-instruction-cache" },
+ { "l2" , },
+ { "dtlb", },
+ { "itlb", },
+ { "bpu" , "btb", "branch-cache", NULL },
+};
+
+static char *hw_cache_op [][MAX_ALIASES] = {
+ { "read" , "load" },
+ { "write" , "store" },
+ { "prefetch" , "speculative-read", "speculative-load" },
+};
+
+static char *hw_cache_result [][MAX_ALIASES] = {
+ { "access", "ops" },
+ { "miss", },
+};
+
char *event_name(int counter)
{
__u64 config = attrs[counter].config;
@@ -86,6 +111,30 @@ char *event_name(int counter)
return hw_event_names[config];
return "unknown-hardware";

+ case PERF_TYPE_HW_CACHE: {
+ __u8 cache_type, cache_op, cache_result;
+ static char name[100];
+
+ cache_type = (config >> 0) & 0xff;
+ if (cache_type > PERF_COUNT_HW_CACHE_MAX)
+ return "unknown-ext-hardware-cache-type";
+
+ cache_op = (config >> 8) & 0xff;
+ if (cache_type > PERF_COUNT_HW_CACHE_OP_MAX)
+ return "unknown-ext-hardware-cache-op-type";
+
+ cache_result = (config >> 16) & 0xff;
+ if (cache_type > PERF_COUNT_HW_CACHE_RESULT_MAX)
+ return "unknown-ext-hardware-cache-result-type";
+
+ sprintf(name, "%s:%s:%s",
+ hw_cache[cache_type][0],
+ hw_cache_op[cache_op][0],
+ hw_cache_result[cache_result][0]);
+
+ return name;
+ }
+
case PERF_TYPE_SOFTWARE:
if (config < PERF_SW_EVENTS_MAX)
return sw_event_names[config];
@@ -98,11 +147,60 @@ char *event_name(int counter)
return "unknown";
}

+static int parse_aliases(const char *str, char *names[][MAX_ALIASES], int size)
+{
+ int i, j;
+
+ for (i = 0; i < size; i++) {
+ for (j = 0; j < MAX_ALIASES; j++) {
+ if (!names[i][j])
+ break;
+ if (strcasestr(str, names[i][j]))
+ return i;
+ }
+ }
+
+ return 0;
+}
+
+static int parse_generic_hw_symbols(const char *str, struct perf_counter_attr *attr)
+{
+ __u8 cache_type = -1, cache_op = 0, cache_result = 0;
+
+ cache_type = parse_aliases(str, hw_cache, PERF_COUNT_HW_CACHE_MAX);
+ /*
+ * No fallback - if we cannot get a clear cache type
+ * then bail out:
+ */
+ if (cache_type == -1)
+ return -EINVAL;
+
+ cache_op = parse_aliases(str, hw_cache_op, PERF_COUNT_HW_CACHE_OP_MAX);
+ /*
+ * Fall back to reads:
+ */
+ if (cache_type == -1)
+ cache_type = PERF_COUNT_HW_CACHE_OP_READ;
+
+ cache_result = parse_aliases(str, hw_cache_result,
+ PERF_COUNT_HW_CACHE_RESULT_MAX);
+ /*
+ * Fall back to accesses:
+ */
+ if (cache_result == -1)
+ cache_result = PERF_COUNT_HW_CACHE_RESULT_ACCESS;
+
+ attr->config = cache_type | (cache_op << 8) | (cache_result << 16);
+ attr->type = PERF_TYPE_HW_CACHE;
+
+ return 0;
+}
+
/*
* Each event can have multiple symbolic names.
* Symbolic names are (almost) exactly matched.
*/
-static int match_event_symbols(const char *str, struct perf_counter_attr *attr)
+static int parse_event_symbols(const char *str, struct perf_counter_attr *attr)
{
__u64 config, id;
int type;
@@ -147,7 +245,7 @@ static int match_event_symbols(const char *str, struct perf_counter_attr *attr)
}
}

- return -EINVAL;
+ return parse_generic_hw_symbols(str, attr);
}

int parse_events(const struct option *opt, const char *str, int unset)
@@ -160,7 +258,7 @@ again:
if (nr_counters == MAX_COUNTERS)
return -1;

- ret = match_event_symbols(str, &attr);
+ ret = parse_event_symbols(str, &attr);
if (ret < 0)
return ret;

diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index 430e048..e86679f 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -83,6 +83,128 @@ static u64 intel_pmu_event_map(int event)
return intel_perfmon_event_map[event];
}

+/*
+ * Generalized hw caching related event table, filled
+ * in on a per model basis. A value of 0 means
+ * 'not supported', -1 means 'event makes no sense on
+ * this CPU', any other value means the raw event
+ * ID.
+ */
+
+#define C(x) PERF_COUNT_HW_CACHE_##x
+
+static u64 __read_mostly hw_cache_event_ids
+ [PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX];
+
+static const u64 nehalem_hw_cache_event_ids
+ [PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] =
+{
+ [ C(L1D) ] = {
+ [ C(OP_READ) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0f40, /* L1D_CACHE_LD.MESI */
+ [ C(RESULT_MISS) ] = 0x0140, /* L1D_CACHE_LD.I_STATE */
+ },
+ [ C(OP_WRITE) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0f41, /* L1D_CACHE_ST.MESI */
+ [ C(RESULT_MISS) ] = 0x0141, /* L1D_CACHE_ST.I_STATE */
+ },
+ [ C(OP_PREFETCH) ] = {
+ [ C(RESULT_ACCESS) ] = 0x014e, /* L1D_PREFETCH.REQUESTS */
+ [ C(RESULT_MISS) ] = 0x024e, /* L1D_PREFETCH.MISS */
+ },
+ },
+ [ C(L1I ) ] = {
+ [ C(OP_READ) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0480, /* L1I.READS */
+ [ C(RESULT_MISS) ] = 0x0280, /* L1I.MISSES */
+ },
+ [ C(OP_WRITE) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ [ C(OP_PREFETCH) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0,
+ [ C(RESULT_MISS) ] = 0x0,
+ },
+ },
+ [ C(L2 ) ] = {
+ [ C(OP_READ) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0324, /* L2_RQSTS.LOADS */
+ [ C(RESULT_MISS) ] = 0x0224, /* L2_RQSTS.LD_MISS */
+ },
+ [ C(OP_WRITE) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0c24, /* L2_RQSTS.RFOS */
+ [ C(RESULT_MISS) ] = 0x0824, /* L2_RQSTS.RFO_MISS */
+ },
+ [ C(OP_PREFETCH) ] = {
+ [ C(RESULT_ACCESS) ] = 0xc024, /* L2_RQSTS.PREFETCHES */
+ [ C(RESULT_MISS) ] = 0x8024, /* L2_RQSTS.PREFETCH_MISS */
+ },
+ },
+ [ C(DTLB) ] = {
+ [ C(OP_READ) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0f40, /* L1D_CACHE_LD.MESI (alias) */
+ [ C(RESULT_MISS) ] = 0x0108, /* DTLB_LOAD_MISSES.ANY */
+ },
+ [ C(OP_WRITE) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0f41, /* L1D_CACHE_ST.MESI (alias) */
+ [ C(RESULT_MISS) ] = 0x010c, /* MEM_STORE_RETIRED.DTLB_MISS */
+ },
+ [ C(OP_PREFETCH) ] = {
+ [ C(RESULT_ACCESS) ] = 0x0,
+ [ C(RESULT_MISS) ] = 0x0,
+ },
+ },
+ [ C(ITLB) ] = {
+ [ C(OP_READ) ] = {
+ [ C(RESULT_ACCESS) ] = 0x01c0, /* INST_RETIRED.ANY_P */
+ [ C(RESULT_MISS) ] = 0x0185, /* ITLB_MISS_RETIRED */
+ },
+ [ C(OP_WRITE) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ [ C(OP_PREFETCH) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ },
+ [ C(BPU ) ] = {
+ [ C(OP_READ) ] = {
+ [ C(RESULT_ACCESS) ] = 0x00c4, /* BR_INST_RETIRED.ALL_BRANCHES */
+ [ C(RESULT_MISS) ] = 0x03e8, /* BPU_CLEARS.ANY */
+ },
+ [ C(OP_WRITE) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ [ C(OP_PREFETCH) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ },
+};
+
+static const u64 core2_hw_cache_event_ids
+ [PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] =
+{
+ /* To be filled in */
+};
+
+static const u64 atom_hw_cache_event_ids
+ [PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] =
+{
+ /* To be filled in */
+};
+
static u64 intel_pmu_raw_event(u64 event)
{
#define CORE_EVNTSEL_EVENT_MASK 0x000000FFULL
@@ -246,6 +368,39 @@ static inline int x86_pmu_initialized(void)
return x86_pmu.handle_irq != NULL;
}

+static inline int
+set_ext_hw_attr(struct hw_perf_counter *hwc, struct perf_counter_attr *attr)
+{
+ unsigned int cache_type, cache_op, cache_result;
+ u64 config, val;
+
+ config = attr->config;
+
+ cache_type = (config >> 0) & 0xff;
+ if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
+ return -EINVAL;
+
+ cache_op = (config >> 8) & 0xff;
+ if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
+ return -EINVAL;
+
+ cache_result = (config >> 16) & 0xff;
+ if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+ return -EINVAL;
+
+ val = hw_cache_event_ids[cache_type][cache_op][cache_result];
+
+ if (val == 0)
+ return -ENOENT;
+
+ if (val == -1)
+ return -EINVAL;
+
+ hwc->config |= val;
+
+ return 0;
+}
+
/*
* Setup the hardware configuration for a given attr_type
*/
@@ -288,22 +443,25 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
hwc->sample_period = x86_pmu.max_period;

atomic64_set(&hwc->period_left, hwc->sample_period);
+ counter->destroy = hw_perf_counter_destroy;

/*
* Raw event type provide the config in the event structure
*/
if (attr->type == PERF_TYPE_RAW) {
hwc->config |= x86_pmu.raw_event(attr->config);
- } else {
- if (attr->config >= x86_pmu.max_events)
- return -EINVAL;
- /*
- * The generic map:
- */
- hwc->config |= x86_pmu.event_map(attr->config);
+ return 0;
}

- counter->destroy = hw_perf_counter_destroy;
+ if (attr->type == PERF_TYPE_HW_CACHE)
+ return set_ext_hw_attr(hwc, attr);
+
+ if (attr->config >= x86_pmu.max_events)
+ return -EINVAL;
+ /*
+ * The generic map:
+ */
+ hwc->config |= x86_pmu.event_map(attr->config);

return 0;
}
@@ -989,6 +1147,33 @@ static int intel_pmu_init(void)

rdmsrl(MSR_CORE_PERF_GLOBAL_CTRL, x86_pmu.intel_ctrl);

+ /*
+ * Nehalem:
+ */
+ switch (boot_cpu_data.x86_model) {
+ case 17:
+ memcpy(hw_cache_event_ids, core2_hw_cache_event_ids,
+ sizeof(u64)*PERF_COUNT_HW_CACHE_MAX*
+ PERF_COUNT_HW_CACHE_OP_MAX*PERF_COUNT_HW_CACHE_RESULT_MAX);
+
+ pr_info("... installed Core2 event tables\n");
+ break;
+ default:
+ case 26:
+ memcpy(hw_cache_event_ids, nehalem_hw_cache_event_ids,
+ sizeof(u64)*PERF_COUNT_HW_CACHE_MAX*
+ PERF_COUNT_HW_CACHE_OP_MAX*PERF_COUNT_HW_CACHE_RESULT_MAX);
+
+ pr_info("... installed Nehalem/Corei7 event tables\n");
+ break;
+ case 28:
+ memcpy(hw_cache_event_ids, atom_hw_cache_event_ids,
+ sizeof(u64)*PERF_COUNT_HW_CACHE_MAX*
+ PERF_COUNT_HW_CACHE_OP_MAX*PERF_COUNT_HW_CACHE_RESULT_MAX);
+
+ pr_info("... installed Atom event tables\n");
+ break;
+ }
return 0;
}

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index f794c69..3586df8 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -28,6 +28,7 @@ enum perf_event_types {
PERF_TYPE_HARDWARE = 0,
PERF_TYPE_SOFTWARE = 1,
PERF_TYPE_TRACEPOINT = 2,
+ PERF_TYPE_HW_CACHE = 3,

/*
* available TYPE space, raw is the max value.
@@ -56,6 +57,39 @@ enum attr_ids {
};

/*
+ * Generalized hardware cache counters:
+ *
+ * { L1-D, L1-I, L2, LLC, ITLB, DTLB, BPU } x
+ * { read, write, prefetch } x
+ * { accesses, misses }
+ */
+enum hw_cache_id {
+ PERF_COUNT_HW_CACHE_L1D,
+ PERF_COUNT_HW_CACHE_L1I,
+ PERF_COUNT_HW_CACHE_L2,
+ PERF_COUNT_HW_CACHE_DTLB,
+ PERF_COUNT_HW_CACHE_ITLB,
+ PERF_COUNT_HW_CACHE_BPU,
+
+ PERF_COUNT_HW_CACHE_MAX,
+};
+
+enum hw_cache_op_id {
+ PERF_COUNT_HW_CACHE_OP_READ,
+ PERF_COUNT_HW_CACHE_OP_WRITE,
+ PERF_COUNT_HW_CACHE_OP_PREFETCH,
+
+ PERF_COUNT_HW_CACHE_OP_MAX,
+};
+
+enum hw_cache_op_result_id {
+ PERF_COUNT_HW_CACHE_RESULT_ACCESS,
+ PERF_COUNT_HW_CACHE_RESULT_MISS,
+
+ PERF_COUNT_HW_CACHE_RESULT_MAX,
+};
+
+/*
* Special "software" counters provided by the kernel, even if the hardware
* does not support performance counters. These counters measure various
* physical and sw events of the kernel (and allow the profiling of them as
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 75ae767..5eacaaf 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -3501,6 +3501,7 @@ perf_counter_alloc(struct perf_counter_attr *attr,

switch (attr->type) {
case PERF_TYPE_HARDWARE:
+ case PERF_TYPE_HW_CACHE:
pmu = hw_perf_counter_init(counter);
break;