Adding support to attach multiple [ku]probes.
Extending both bpf_kprobe_opts and bpf_uprobe_opts structs
with config values to define multiple probes within single
bpf_program__attach_[ku]probe_opts call.
For mutiple probes in bpf_program__attach_kprobe_opts function
the 'func_name' argument is ignored and probes are defined in
bpf_kprobe_opts struct with:
struct {
/* probes count */
__u32 cnt;
/* function names array */
char **funcs;
/* address/offset values array */
union {
__u64 *addrs;
__u64 *offs;
};
} multi;
For mutiple probes in bpf_program__attach_uprobe_opts function
both 'binary_path' and 'func_offset' arguments are ignored and
probes are defined in bpf_kprobe_opts struct with:
/* multi uprobe values */
struct {
/* probes count */
__u32 cnt;
/* paths names array */
const char **paths;
/* offsets values array */
__u64 *offs;
} multi;
The multiple probes attachment is enabled when multi.cnt != 0.
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/include/uapi/linux/perf_event.h | 1 +
tools/lib/bpf/libbpf.c | 30 +++++++++++++++++++++++++--
tools/lib/bpf/libbpf.h | 25 ++++++++++++++++++++--
3 files changed, 52 insertions(+), 4 deletions(-)
diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
index bd8860eeb291..eea80709d1ed 100644
--- a/tools/include/uapi/linux/perf_event.h
+++ b/tools/include/uapi/linux/perf_event.h
@@ -414,6 +414,7 @@ struct perf_event_attr {
union {
__u32 wakeup_events; /* wakeup every n events */
__u32 wakeup_watermark; /* bytes before wakeup */
+ __u32 probe_cnt; /* number of [k,u] probes */
};
__u32 bp_type;
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 34219a0c39a7..b570e93de735 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9631,6 +9631,11 @@ struct perf_event_open_args {
uint64_t offset;
int pid;
size_t ref_ctr_off;
+ struct {
+ __u32 probe_cnt;
+ __u64 config1;
+ __u64 config2;
+ } multi;
};
static int perf_event_open_probe(bool uprobe, struct perf_event_open_args *args)
@@ -9667,8 +9672,15 @@ static int perf_event_open_probe(bool uprobe, struct perf_event_open_args *args)
attr.size = sizeof(attr);
attr.type = type;
attr.config |= (__u64)ref_ctr_off << PERF_UPROBE_REF_CTR_OFFSET_SHIFT;
- attr.config1 = ptr_to_u64(args->name); /* kprobe_func or uprobe_path */
- attr.config2 = args->offset; /* kprobe_addr or probe_offset */
+
+ if (args->multi.probe_cnt) {
+ attr.probe_cnt = args->multi.probe_cnt;
+ attr.config1 = args->multi.config1;
+ attr.config2 = args->multi.config2;
+ } else {
+ attr.config1 = ptr_to_u64(args->name); /* kprobe_func or uprobe_path */
+ attr.config2 = args->offset; /* kprobe_addr or probe_offset */
+ }
/* pid filter is meaningful only for uprobes */
pfd = syscall(__NR_perf_event_open, &attr,
@@ -9807,7 +9819,14 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
.pid = -1,
.ref_ctr_off = 0,
};
+ __u32 probe_cnt = OPTS_GET(opts, multi.cnt, false);
+ if (probe_cnt) {
+ args.multi.probe_cnt = probe_cnt;
+ args.multi.config1 = ptr_to_u64(OPTS_GET(opts, multi.funcs, false));
+ /* multi.addrs and multi.offs share the same array */
+ args.multi.config2 = ptr_to_u64(OPTS_GET(opts, multi.addrs, false));
+ }
pfd = perf_event_open_probe(false /* uprobe */, &args);
} else {
char probe_name[256];
@@ -10006,6 +10025,13 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
.pid = pid,
.ref_ctr_off = ref_ctr_off,
};
+ __u32 probe_cnt = OPTS_GET(opts, multi.cnt, false);
+
+ if (probe_cnt) {
+ args.multi.probe_cnt = probe_cnt;
+ args.multi.config1 = ptr_to_u64(OPTS_GET(opts, multi.paths, false));
+ args.multi.config2 = ptr_to_u64(OPTS_GET(opts, multi.offs, false));
+ }
pfd = perf_event_open_probe(true /* uprobe */, &args);
} else {
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index d02139fec4ac..ae072882b5dd 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -321,9 +321,21 @@ struct bpf_kprobe_opts {
size_t offset;
/* kprobe is return probe */
bool retprobe;
+ /* multi kprobe values */
+ struct {
+ /* probes count */
+ __u32 cnt;
+ /* function names array */
+ char **funcs;
+ /* address/offset values array */
+ union {
+ __u64 *addrs;
+ __u64 *offs;
+ };
+ } multi;
size_t :0;
};
-#define bpf_kprobe_opts__last_field retprobe
+#define bpf_kprobe_opts__last_field multi.addrs
LIBBPF_API struct bpf_link *
bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe,
@@ -344,9 +356,18 @@ struct bpf_uprobe_opts {
__u64 bpf_cookie;
/* uprobe is return probe, invoked at function return time */
bool retprobe;
+ /* multi uprobe values */
+ struct {
+ /* probes count */
+ __u32 cnt;
+ /* paths names array */
+ const char **paths;
+ /* offsets values array */
+ __u64 *offs;
+ } multi;
size_t :0;
};
-#define bpf_uprobe_opts__last_field retprobe
+#define bpf_uprobe_opts__last_field multi.offs
LIBBPF_API struct bpf_link *
bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe,
--
2.33.1
