@@ -1047,7 +1047,7 @@ SKELETONS := $(SKEL_OUT)/bpf_prog_profiler.skel.h
SKELETONS += $(SKEL_OUT)/bperf_leader.skel.h $(SKEL_OUT)/bperf_follower.skel.h
SKELETONS += $(SKEL_OUT)/bperf_cgroup.skel.h $(SKEL_OUT)/func_latency.skel.h
SKELETONS += $(SKEL_OUT)/off_cpu.skel.h $(SKEL_OUT)/lock_contention.skel.h
-SKELETONS += $(SKEL_OUT)/kwork_trace.skel.h
+SKELETONS += $(SKEL_OUT)/kwork_trace.skel.h $(SKEL_OUT)/sample_filter.skel.h
$(SKEL_TMP_OUT) $(LIBAPI_OUTPUT) $(LIBBPF_OUTPUT) $(LIBPERF_OUTPUT) $(LIBSUBCMD_OUTPUT) $(LIBSYMBOL_OUTPUT):
$(Q)$(MKDIR) -p $@
@@ -1,10 +1,74 @@
/* SPDX-License-Identifier: GPL-2.0 */
#include <stdlib.h>
+#include <bpf/bpf.h>
+#include <linux/err.h>
+#include <internal/xyarray.h>
+
+#include "util/debug.h"
+#include "util/evsel.h"
+
#include "util/bpf-filter.h"
#include "util/bpf-filter-flex.h"
#include "util/bpf-filter-bison.h"
+#include "bpf_skel/sample-filter.h"
+#include "bpf_skel/sample_filter.skel.h"
+
+#define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
+
+int perf_bpf_filter__prepare(struct evsel *evsel)
+{
+ int i, x, y, fd;
+ struct sample_filter_bpf *skel;
+ struct bpf_program *prog;
+ struct bpf_link *link;
+ struct perf_bpf_filter_expr *expr;
+
+ skel = sample_filter_bpf__open_and_load();
+ if (!skel) {
+ pr_err("Failed to load perf sample-filter BPF skeleton\n");
+ return -1;
+ }
+
+ i = 0;
+ fd = bpf_map__fd(skel->maps.filters);
+ list_for_each_entry(expr, &evsel->bpf_filters, list) {
+ struct perf_bpf_filter_entry entry = {
+ .op = expr->op,
+ .flags = expr->sample_flags,
+ .value = expr->val,
+ };
+ bpf_map_update_elem(fd, &i, &entry, BPF_ANY);
+ i++;
+ }
+
+ prog = skel->progs.perf_sample_filter;
+ for (x = 0; x < xyarray__max_x(evsel->core.fd); x++) {
+ for (y = 0; y < xyarray__max_y(evsel->core.fd); y++) {
+ link = bpf_program__attach_perf_event(prog, FD(evsel, x, y));
+ if (IS_ERR(link)) {
+ pr_err("Failed to attach perf sample-filter program\n");
+ return PTR_ERR(link);
+ }
+ }
+ }
+ evsel->bpf_skel = skel;
+ return 0;
+}
+
+int perf_bpf_filter__destroy(struct evsel *evsel)
+{
+ struct perf_bpf_filter_expr *expr, *tmp;
+
+ list_for_each_entry_safe(expr, tmp, &evsel->bpf_filters, list) {
+ list_del(&expr->list);
+ free(expr);
+ }
+ sample_filter_bpf__destroy(evsel->bpf_skel);
+ return 0;
+}
+
struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags,
enum perf_bpf_filter_op op,
unsigned long val)
@@ -4,15 +4,7 @@
#include <linux/list.h>
-enum perf_bpf_filter_op {
- PBF_OP_EQ,
- PBF_OP_NEQ,
- PBF_OP_GT,
- PBF_OP_GE,
- PBF_OP_LT,
- PBF_OP_LE,
- PBF_OP_AND,
-};
+#include "bpf_skel/sample-filter.h"
struct perf_bpf_filter_expr {
struct list_head list;
@@ -21,16 +13,30 @@ struct perf_bpf_filter_expr {
unsigned long val;
};
+struct evsel;
+
#ifdef HAVE_BPF_SKEL
struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags,
enum perf_bpf_filter_op op,
unsigned long val);
int perf_bpf_filter__parse(struct list_head *expr_head, const char *str);
+int perf_bpf_filter__prepare(struct evsel *evsel);
+int perf_bpf_filter__destroy(struct evsel *evsel);
+
#else /* !HAVE_BPF_SKEL */
+
static inline int perf_bpf_filter__parse(struct list_head *expr_head __maybe_unused,
const char *str __maybe_unused)
{
- return -ENOSYS;
+ return -EOPNOTSUPP;
+}
+static inline int perf_bpf_filter__prepare(struct evsel *evsel __maybe_unused)
+{
+ return -EOPNOTSUPP;
+}
+static inline int perf_bpf_filter__destroy(struct evsel *evsel __maybe_unused)
+{
+ return -EOPNOTSUPP;
}
#endif /* HAVE_BPF_SKEL*/
#endif /* PERF_UTIL_BPF_FILTER_H */
new file mode 100644
@@ -0,0 +1,24 @@
+#ifndef PERF_UTIL_BPF_SKEL_SAMPLE_FILTER_H
+#define PERF_UTIL_BPF_SKEL_SAMPLE_FILTER_H
+
+#define MAX_FILTERS 32
+
+/* supported filter operations */
+enum perf_bpf_filter_op {
+ PBF_OP_EQ,
+ PBF_OP_NEQ,
+ PBF_OP_GT,
+ PBF_OP_GE,
+ PBF_OP_LT,
+ PBF_OP_LE,
+ PBF_OP_AND
+};
+
+/* BPF map entry for filtering */
+struct perf_bpf_filter_entry {
+ enum perf_bpf_filter_op op;
+ __u64 flags;
+ __u64 value;
+};
+
+#endif /* PERF_UTIL_BPF_SKEL_SAMPLE_FILTER_H */
\ No newline at end of file
new file mode 100644
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+// Copyright (c) 2023 Google
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
+
+#include "sample-filter.h"
+
+/* BPF map that will be filled by user space */
+struct filters {
+ __uint(type, BPF_MAP_TYPE_ARRAY);
+ __type(key, int);
+ __type(value, struct perf_bpf_filter_entry);
+ __uint(max_entries, MAX_FILTERS);
+} filters SEC(".maps");
+
+int dropped;
+
+void *bpf_cast_to_kern_ctx(void *) __ksym;
+
+/* new kernel perf_sample_data definition */
+struct perf_sample_data___new {
+ __u64 sample_flags;
+} __attribute__((preserve_access_index));
+
+/* helper function to return the given perf sample data */
+static inline __u64 perf_get_sample(struct bpf_perf_event_data_kern *kctx,
+ struct perf_bpf_filter_entry *entry)
+{
+ struct perf_sample_data___new *data = (void *)kctx->data;
+
+ if (!bpf_core_field_exists(data->sample_flags) ||
+ (data->sample_flags & entry->flags) == 0)
+ return 0;
+
+ switch (entry->flags) {
+ case PERF_SAMPLE_IP:
+ return kctx->data->ip;
+ case PERF_SAMPLE_ID:
+ return kctx->data->id;
+ case PERF_SAMPLE_TID:
+ return kctx->data->tid_entry.tid;
+ case PERF_SAMPLE_CPU:
+ return kctx->data->cpu_entry.cpu;
+ case PERF_SAMPLE_TIME:
+ return kctx->data->time;
+ case PERF_SAMPLE_ADDR:
+ return kctx->data->addr;
+ case PERF_SAMPLE_PERIOD:
+ return kctx->data->period;
+ case PERF_SAMPLE_TRANSACTION:
+ return kctx->data->txn;
+ case PERF_SAMPLE_WEIGHT:
+ return kctx->data->weight.full;
+ case PERF_SAMPLE_PHYS_ADDR:
+ return kctx->data->phys_addr;
+ case PERF_SAMPLE_CODE_PAGE_SIZE:
+ return kctx->data->code_page_size;
+ case PERF_SAMPLE_DATA_PAGE_SIZE:
+ return kctx->data->data_page_size;
+ default:
+ break;
+ }
+ return 0;
+}
+
+/* BPF program to be called from perf event overflow handler */
+SEC("perf_event")
+int perf_sample_filter(void *ctx)
+{
+ struct bpf_perf_event_data_kern *kctx;
+ struct perf_bpf_filter_entry *entry;
+ __u64 sample_data;
+ int i;
+
+ kctx = bpf_cast_to_kern_ctx(ctx);
+
+ for (i = 0; i < MAX_FILTERS; i++) {
+ int key = i; /* needed for verifier :( */
+
+ entry = bpf_map_lookup_elem(&filters, &key);
+ if (entry == NULL)
+ break;
+ sample_data = perf_get_sample(kctx, entry);
+
+ switch (entry->op) {
+ case PBF_OP_EQ:
+ if (!(sample_data == entry->value))
+ goto drop;
+ break;
+ case PBF_OP_NEQ:
+ if (!(sample_data != entry->value))
+ goto drop;
+ break;
+ case PBF_OP_GT:
+ if (!(sample_data > entry->value))
+ goto drop;
+ break;
+ case PBF_OP_GE:
+ if (!(sample_data >= entry->value))
+ goto drop;
+ break;
+ case PBF_OP_LT:
+ if (!(sample_data < entry->value))
+ goto drop;
+ break;
+ case PBF_OP_LE:
+ if (!(sample_data <= entry->value))
+ goto drop;
+ break;
+ case PBF_OP_AND:
+ if (!(sample_data & entry->value))
+ goto drop;
+ break;
+ }
+ }
+ /* generate sample data */
+ return 1;
+
+drop:
+ __sync_fetch_and_add(&dropped, 1);
+ return 0;
+}
+
+char LICENSE[] SEC("license") = "Dual BSD/GPL";
@@ -151,8 +151,10 @@ struct evsel {
*/
struct bpf_counter_ops *bpf_counter_ops;
- /* for perf-stat -b */
- struct list_head bpf_counter_list;
+ union {
+ struct list_head bpf_counter_list; /* for perf-stat -b */
+ struct list_head bpf_filters; /* for perf-record --filter */
+ };
/* for perf-stat --use-bpf */
int bperf_leader_prog_fd;
@@ -160,6 +162,7 @@ struct evsel {
union {
struct bperf_leader_bpf *leader_skel;
struct bperf_follower_bpf *follower_skel;
+ void *bpf_skel;
};
unsigned long open_flags;
int precise_ip_original;