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-rw-r--r--include/linux/perf_event.h7
-rw-r--r--include/uapi/linux/bpf.h29
-rw-r--r--kernel/bpf/arraymap.c2
-rw-r--r--kernel/bpf/verifier.c4
-rw-r--r--kernel/events/core.c15
-rw-r--r--kernel/trace/bpf_trace.c73
-rw-r--r--samples/bpf/trace_event_kern.c10
-rw-r--r--samples/bpf/trace_event_user.c13
-rw-r--r--samples/bpf/tracex6_kern.c26
-rw-r--r--samples/bpf/tracex6_user.c13
-rw-r--r--tools/include/uapi/linux/bpf.h4
-rw-r--r--tools/testing/selftests/bpf/bpf_helpers.h6
12 files changed, 183 insertions, 19 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 8e22f24ded6a..79b18a20cf5d 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -806,6 +806,7 @@ struct perf_output_handle {
struct bpf_perf_event_data_kern {
struct pt_regs *regs;
struct perf_sample_data *data;
+ struct perf_event *event;
};
#ifdef CONFIG_CGROUP_PERF
@@ -884,7 +885,8 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr,
void *context);
extern void perf_pmu_migrate_context(struct pmu *pmu,
int src_cpu, int dst_cpu);
-int perf_event_read_local(struct perf_event *event, u64 *value);
+int perf_event_read_local(struct perf_event *event, u64 *value,
+ u64 *enabled, u64 *running);
extern u64 perf_event_read_value(struct perf_event *event,
u64 *enabled, u64 *running);
@@ -1286,7 +1288,8 @@ static inline const struct perf_event_attr *perf_event_attrs(struct perf_event *
{
return ERR_PTR(-EINVAL);
}
-static inline int perf_event_read_local(struct perf_event *event, u64 *value)
+static inline int perf_event_read_local(struct perf_event *event, u64 *value,
+ u64 *enabled, u64 *running)
{
return -EINVAL;
}
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 6082faf5fd2a..5bbbec17aa5a 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -641,6 +641,21 @@ union bpf_attr {
* @xdp_md: pointer to xdp_md
* @delta: An positive/negative integer to be added to xdp_md.data_meta
* Return: 0 on success or negative on error
+ *
+ * int bpf_perf_event_read_value(map, flags, buf, buf_size)
+ * read perf event counter value and perf event enabled/running time
+ * @map: pointer to perf_event_array map
+ * @flags: index of event in the map or bitmask flags
+ * @buf: buf to fill
+ * @buf_size: size of the buf
+ * Return: 0 on success or negative error code
+ *
+ * int bpf_perf_prog_read_value(ctx, buf, buf_size)
+ * read perf prog attached perf event counter and enabled/running time
+ * @ctx: pointer to ctx
+ * @buf: buf to fill
+ * @buf_size: size of the buf
+ * Return : 0 on success or negative error code
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -697,7 +712,9 @@ union bpf_attr {
FN(redirect_map), \
FN(sk_redirect_map), \
FN(sock_map_update), \
- FN(xdp_adjust_meta),
+ FN(xdp_adjust_meta), \
+ FN(perf_event_read_value), \
+ FN(perf_prog_read_value),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
@@ -741,7 +758,9 @@ enum bpf_func_id {
#define BPF_F_ZERO_CSUM_TX (1ULL << 1)
#define BPF_F_DONT_FRAGMENT (1ULL << 2)
-/* BPF_FUNC_perf_event_output and BPF_FUNC_perf_event_read flags. */
+/* BPF_FUNC_perf_event_output, BPF_FUNC_perf_event_read and
+ * BPF_FUNC_perf_event_read_value flags.
+ */
#define BPF_F_INDEX_MASK 0xffffffffULL
#define BPF_F_CURRENT_CPU BPF_F_INDEX_MASK
/* BPF_FUNC_perf_event_output for sk_buff input context. */
@@ -934,4 +953,10 @@ enum {
#define TCP_BPF_IW 1001 /* Set TCP initial congestion window */
#define TCP_BPF_SNDCWND_CLAMP 1002 /* Set sndcwnd_clamp */
+struct bpf_perf_event_value {
+ __u64 counter;
+ __u64 enabled;
+ __u64 running;
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 98c0f00c3f5e..68d866628be0 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -492,7 +492,7 @@ static void *perf_event_fd_array_get_ptr(struct bpf_map *map,
ee = ERR_PTR(-EOPNOTSUPP);
event = perf_file->private_data;
- if (perf_event_read_local(event, &value) == -EOPNOTSUPP)
+ if (perf_event_read_local(event, &value, NULL, NULL) == -EOPNOTSUPP)
goto err_out;
ee = bpf_event_entry_gen(perf_file, map_file);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 52b022310f6a..590125e29161 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1552,7 +1552,8 @@ static int check_map_func_compatibility(struct bpf_map *map, int func_id)
break;
case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
if (func_id != BPF_FUNC_perf_event_read &&
- func_id != BPF_FUNC_perf_event_output)
+ func_id != BPF_FUNC_perf_event_output &&
+ func_id != BPF_FUNC_perf_event_read_value)
goto error;
break;
case BPF_MAP_TYPE_STACK_TRACE:
@@ -1595,6 +1596,7 @@ static int check_map_func_compatibility(struct bpf_map *map, int func_id)
break;
case BPF_FUNC_perf_event_read:
case BPF_FUNC_perf_event_output:
+ case BPF_FUNC_perf_event_read_value:
if (map->map_type != BPF_MAP_TYPE_PERF_EVENT_ARRAY)
goto error;
break;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 6bc21e202ae4..902149f05381 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -3684,10 +3684,12 @@ static inline u64 perf_event_count(struct perf_event *event)
* will not be local and we cannot read them atomically
* - must not have a pmu::count method
*/
-int perf_event_read_local(struct perf_event *event, u64 *value)
+int perf_event_read_local(struct perf_event *event, u64 *value,
+ u64 *enabled, u64 *running)
{
unsigned long flags;
int ret = 0;
+ u64 now;
/*
* Disabling interrupts avoids all counter scheduling (context
@@ -3718,13 +3720,21 @@ int perf_event_read_local(struct perf_event *event, u64 *value)
goto out;
}
+ now = event->shadow_ctx_time + perf_clock();
+ if (enabled)
+ *enabled = now - event->tstamp_enabled;
/*
* If the event is currently on this CPU, its either a per-task event,
* or local to this CPU. Furthermore it means its ACTIVE (otherwise
* oncpu == -1).
*/
- if (event->oncpu == smp_processor_id())
+ if (event->oncpu == smp_processor_id()) {
event->pmu->read(event);
+ if (running)
+ *running = now - event->tstamp_running;
+ } else if (running) {
+ *running = event->total_time_running;
+ }
*value = local64_read(&event->count);
out:
@@ -8072,6 +8082,7 @@ static void bpf_overflow_handler(struct perf_event *event,
struct bpf_perf_event_data_kern ctx = {
.data = data,
.regs = regs,
+ .event = event,
};
int ret = 0;
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index dc498b605d5d..04ea5314f2bc 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -255,14 +255,14 @@ const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
return &bpf_trace_printk_proto;
}
-BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
+static __always_inline int
+get_map_perf_counter(struct bpf_map *map, u64 flags,
+ u64 *value, u64 *enabled, u64 *running)
{
struct bpf_array *array = container_of(map, struct bpf_array, map);
unsigned int cpu = smp_processor_id();
u64 index = flags & BPF_F_INDEX_MASK;
struct bpf_event_entry *ee;
- u64 value = 0;
- int err;
if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
return -EINVAL;
@@ -275,7 +275,15 @@ BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
if (!ee)
return -ENOENT;
- err = perf_event_read_local(ee->event, &value);
+ return perf_event_read_local(ee->event, value, enabled, running);
+}
+
+BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
+{
+ u64 value = 0;
+ int err;
+
+ err = get_map_perf_counter(map, flags, &value, NULL, NULL);
/*
* this api is ugly since we miss [-22..-2] range of valid
* counter values, but that's uapi
@@ -293,6 +301,33 @@ static const struct bpf_func_proto bpf_perf_event_read_proto = {
.arg2_type = ARG_ANYTHING,
};
+BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
+ struct bpf_perf_event_value *, buf, u32, size)
+{
+ int err = -EINVAL;
+
+ if (unlikely(size != sizeof(struct bpf_perf_event_value)))
+ goto clear;
+ err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
+ &buf->running);
+ if (unlikely(err))
+ goto clear;
+ return 0;
+clear:
+ memset(buf, 0, size);
+ return err;
+}
+
+static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
+ .func = bpf_perf_event_read_value,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg4_type = ARG_CONST_SIZE,
+};
+
static DEFINE_PER_CPU(struct perf_sample_data, bpf_sd);
static __always_inline u64
@@ -499,6 +534,8 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func
return &bpf_perf_event_output_proto;
case BPF_FUNC_get_stackid:
return &bpf_get_stackid_proto;
+ case BPF_FUNC_perf_event_read_value:
+ return &bpf_perf_event_read_value_proto;
default:
return tracing_func_proto(func_id);
}
@@ -576,6 +613,32 @@ static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
.arg3_type = ARG_ANYTHING,
};
+BPF_CALL_3(bpf_perf_prog_read_value_tp, struct bpf_perf_event_data_kern *, ctx,
+ struct bpf_perf_event_value *, buf, u32, size)
+{
+ int err = -EINVAL;
+
+ if (unlikely(size != sizeof(struct bpf_perf_event_value)))
+ goto clear;
+ err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
+ &buf->running);
+ if (unlikely(err))
+ goto clear;
+ return 0;
+clear:
+ memset(buf, 0, size);
+ return err;
+}
+
+static const struct bpf_func_proto bpf_perf_prog_read_value_proto_tp = {
+ .func = bpf_perf_prog_read_value_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg3_type = ARG_CONST_SIZE,
+};
+
static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
@@ -583,6 +646,8 @@ static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id)
return &bpf_perf_event_output_proto_tp;
case BPF_FUNC_get_stackid:
return &bpf_get_stackid_proto_tp;
+ case BPF_FUNC_perf_prog_read_value:
+ return &bpf_perf_prog_read_value_proto_tp;
default:
return tracing_func_proto(func_id);
}
diff --git a/samples/bpf/trace_event_kern.c b/samples/bpf/trace_event_kern.c
index 41b6115a32eb..a77a583d94d4 100644
--- a/samples/bpf/trace_event_kern.c
+++ b/samples/bpf/trace_event_kern.c
@@ -37,10 +37,14 @@ struct bpf_map_def SEC("maps") stackmap = {
SEC("perf_event")
int bpf_prog1(struct bpf_perf_event_data *ctx)
{
+ char time_fmt1[] = "Time Enabled: %llu, Time Running: %llu";
+ char time_fmt2[] = "Get Time Failed, ErrCode: %d";
char fmt[] = "CPU-%d period %lld ip %llx";
u32 cpu = bpf_get_smp_processor_id();
+ struct bpf_perf_event_value value_buf;
struct key_t key;
u64 *val, one = 1;
+ int ret;
if (ctx->sample_period < 10000)
/* ignore warmup */
@@ -54,6 +58,12 @@ int bpf_prog1(struct bpf_perf_event_data *ctx)
return 0;
}
+ ret = bpf_perf_prog_read_value(ctx, (void *)&value_buf, sizeof(struct bpf_perf_event_value));
+ if (!ret)
+ bpf_trace_printk(time_fmt1, sizeof(time_fmt1), value_buf.enabled, value_buf.running);
+ else
+ bpf_trace_printk(time_fmt2, sizeof(time_fmt2), ret);
+
val = bpf_map_lookup_elem(&counts, &key);
if (val)
(*val)++;
diff --git a/samples/bpf/trace_event_user.c b/samples/bpf/trace_event_user.c
index 7bd827b84a67..bf4f1b6d9a52 100644
--- a/samples/bpf/trace_event_user.c
+++ b/samples/bpf/trace_event_user.c
@@ -127,6 +127,9 @@ static void test_perf_event_all_cpu(struct perf_event_attr *attr)
int *pmu_fd = malloc(nr_cpus * sizeof(int));
int i, error = 0;
+ /* system wide perf event, no need to inherit */
+ attr->inherit = 0;
+
/* open perf_event on all cpus */
for (i = 0; i < nr_cpus; i++) {
pmu_fd[i] = sys_perf_event_open(attr, -1, i, -1, 0);
@@ -154,6 +157,11 @@ static void test_perf_event_task(struct perf_event_attr *attr)
{
int pmu_fd;
+ /* per task perf event, enable inherit so the "dd ..." command can be traced properly.
+ * Enabling inherit will cause bpf_perf_prog_read_time helper failure.
+ */
+ attr->inherit = 1;
+
/* open task bound event */
pmu_fd = sys_perf_event_open(attr, 0, -1, -1, 0);
if (pmu_fd < 0) {
@@ -175,14 +183,12 @@ static void test_bpf_perf_event(void)
.freq = 1,
.type = PERF_TYPE_HARDWARE,
.config = PERF_COUNT_HW_CPU_CYCLES,
- .inherit = 1,
};
struct perf_event_attr attr_type_sw = {
.sample_freq = SAMPLE_FREQ,
.freq = 1,
.type = PERF_TYPE_SOFTWARE,
.config = PERF_COUNT_SW_CPU_CLOCK,
- .inherit = 1,
};
struct perf_event_attr attr_hw_cache_l1d = {
.sample_freq = SAMPLE_FREQ,
@@ -192,7 +198,6 @@ static void test_bpf_perf_event(void)
PERF_COUNT_HW_CACHE_L1D |
(PERF_COUNT_HW_CACHE_OP_READ << 8) |
(PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16),
- .inherit = 1,
};
struct perf_event_attr attr_hw_cache_branch_miss = {
.sample_freq = SAMPLE_FREQ,
@@ -202,7 +207,6 @@ static void test_bpf_perf_event(void)
PERF_COUNT_HW_CACHE_BPU |
(PERF_COUNT_HW_CACHE_OP_READ << 8) |
(PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
- .inherit = 1,
};
struct perf_event_attr attr_type_raw = {
.sample_freq = SAMPLE_FREQ,
@@ -210,7 +214,6 @@ static void test_bpf_perf_event(void)
.type = PERF_TYPE_RAW,
/* Intel Instruction Retired */
.config = 0xc0,
- .inherit = 1,
};
printf("Test HW_CPU_CYCLES\n");
diff --git a/samples/bpf/tracex6_kern.c b/samples/bpf/tracex6_kern.c
index e7d180305974..46c557afac73 100644
--- a/samples/bpf/tracex6_kern.c
+++ b/samples/bpf/tracex6_kern.c
@@ -15,6 +15,12 @@ struct bpf_map_def SEC("maps") values = {
.value_size = sizeof(u64),
.max_entries = 64,
};
+struct bpf_map_def SEC("maps") values2 = {
+ .type = BPF_MAP_TYPE_HASH,
+ .key_size = sizeof(int),
+ .value_size = sizeof(struct bpf_perf_event_value),
+ .max_entries = 64,
+};
SEC("kprobe/htab_map_get_next_key")
int bpf_prog1(struct pt_regs *ctx)
@@ -37,5 +43,25 @@ int bpf_prog1(struct pt_regs *ctx)
return 0;
}
+SEC("kprobe/htab_map_lookup_elem")
+int bpf_prog2(struct pt_regs *ctx)
+{
+ u32 key = bpf_get_smp_processor_id();
+ struct bpf_perf_event_value *val, buf;
+ int error;
+
+ error = bpf_perf_event_read_value(&counters, key, &buf, sizeof(buf));
+ if (error)
+ return 0;
+
+ val = bpf_map_lookup_elem(&values2, &key);
+ if (val)
+ *val = buf;
+ else
+ bpf_map_update_elem(&values2, &key, &buf, BPF_NOEXIST);
+
+ return 0;
+}
+
char _license[] SEC("license") = "GPL";
u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/samples/bpf/tracex6_user.c b/samples/bpf/tracex6_user.c
index a05a99a0752f..3341a96fc046 100644
--- a/samples/bpf/tracex6_user.c
+++ b/samples/bpf/tracex6_user.c
@@ -22,6 +22,7 @@
static void check_on_cpu(int cpu, struct perf_event_attr *attr)
{
+ struct bpf_perf_event_value value2;
int pmu_fd, error = 0;
cpu_set_t set;
__u64 value;
@@ -46,8 +47,18 @@ static void check_on_cpu(int cpu, struct perf_event_attr *attr)
fprintf(stderr, "Value missing for CPU %d\n", cpu);
error = 1;
goto on_exit;
+ } else {
+ fprintf(stderr, "CPU %d: %llu\n", cpu, value);
+ }
+ /* The above bpf_map_lookup_elem should trigger the second kprobe */
+ if (bpf_map_lookup_elem(map_fd[2], &cpu, &value2)) {
+ fprintf(stderr, "Value2 missing for CPU %d\n", cpu);
+ error = 1;
+ goto on_exit;
+ } else {
+ fprintf(stderr, "CPU %d: counter: %llu, enabled: %llu, running: %llu\n", cpu,
+ value2.counter, value2.enabled, value2.running);
}
- fprintf(stderr, "CPU %d: %llu\n", cpu, value);
on_exit:
assert(bpf_map_delete_elem(map_fd[0], &cpu) == 0 || error);
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index cb2b9f95160a..0894fd20b12b 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -697,7 +697,9 @@ union bpf_attr {
FN(redirect_map), \
FN(sk_redirect_map), \
FN(sock_map_update), \
- FN(xdp_adjust_meta),
+ FN(xdp_adjust_meta), \
+ FN(perf_event_read_value), \
+ FN(perf_prog_read_value),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index a56053db26f5..e25dbf6038cf 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -72,6 +72,12 @@ static int (*bpf_sk_redirect_map)(void *map, int key, int flags) =
static int (*bpf_sock_map_update)(void *map, void *key, void *value,
unsigned long long flags) =
(void *) BPF_FUNC_sock_map_update;
+static int (*bpf_perf_event_read_value)(void *map, unsigned long long flags,
+ void *buf, unsigned int buf_size) =
+ (void *) BPF_FUNC_perf_event_read_value;
+static int (*bpf_perf_prog_read_value)(void *ctx, void *buf,
+ unsigned int buf_size) =
+ (void *) BPF_FUNC_perf_prog_read_value;
/* llvm builtin functions that eBPF C program may use to
generated by cgit v1.2.3 (git 2.39.0) at 2025-01-26 22:48:07 +0300