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| author | Jiri Olsa <jolsa@kernel.org> | 2023-09-20 23:31:39 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-01 01:58:19 +0100 |
| commit | 99bf10e92a3f9faf75275a9c6382bd14680290fb (patch) | |
| tree | 1e984acdee441a0dfdc9360156d8d8cbbab80027 /kernel/trace | |
| parent | f4381ccf1ed1938e1d551cc1ea8b526292873230 (diff) | |
| download | linux-99bf10e92a3f9faf75275a9c6382bd14680290fb.tar.gz linux-99bf10e92a3f9faf75275a9c6382bd14680290fb.tar.bz2 linux-99bf10e92a3f9faf75275a9c6382bd14680290fb.zip | |
bpf: Add missed value to kprobe perf link info
[ Upstream commit 3acf8ace68230e9558cf916847f1cc9f208abdf1 ]
Add missed value to kprobe attached through perf link info to
hold the stats of missed kprobe handler execution.
The kprobe's missed counter gets incremented when kprobe handler
is not executed due to another kprobe running on the same cpu.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-4-jolsa@kernel.org
Stable-dep-of: 4deecdd29cf2 ("bpf: fix unpopulated name_len field in perf_event link info")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/bpf_trace.c | 5 | ||||
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 14 |
2 files changed, 14 insertions, 5 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index eca858bde804..bbdc4199748b 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2389,7 +2389,8 @@ int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog) int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, u32 *fd_type, const char **buf, - u64 *probe_offset, u64 *probe_addr) + u64 *probe_offset, u64 *probe_addr, + unsigned long *missed) { bool is_tracepoint, is_syscall_tp; struct bpf_prog *prog; @@ -2424,7 +2425,7 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, #ifdef CONFIG_KPROBE_EVENTS if (flags & TRACE_EVENT_FL_KPROBE) err = bpf_get_kprobe_info(event, fd_type, buf, - probe_offset, probe_addr, + probe_offset, probe_addr, missed, event->attr.type == PERF_TYPE_TRACEPOINT); #endif #ifdef CONFIG_UPROBE_EVENTS diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 47812aa16bb5..52f8b537dd0a 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1249,6 +1249,12 @@ static const struct file_operations kprobe_events_ops = { .write = probes_write, }; +static unsigned long trace_kprobe_missed(struct trace_kprobe *tk) +{ + return trace_kprobe_is_return(tk) ? + tk->rp.kp.nmissed + tk->rp.nmissed : tk->rp.kp.nmissed; +} + /* Probes profiling interfaces */ static int probes_profile_seq_show(struct seq_file *m, void *v) { @@ -1260,8 +1266,7 @@ static int probes_profile_seq_show(struct seq_file *m, void *v) return 0; tk = to_trace_kprobe(ev); - nmissed = trace_kprobe_is_return(tk) ? - tk->rp.kp.nmissed + tk->rp.nmissed : tk->rp.kp.nmissed; + nmissed = trace_kprobe_missed(tk); seq_printf(m, " %-44s %15lu %15lu\n", trace_probe_name(&tk->tp), trace_kprobe_nhit(tk), @@ -1607,7 +1612,8 @@ NOKPROBE_SYMBOL(kretprobe_perf_func); int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, const char **symbol, u64 *probe_offset, - u64 *probe_addr, bool perf_type_tracepoint) + u64 *probe_addr, unsigned long *missed, + bool perf_type_tracepoint) { const char *pevent = trace_event_name(event->tp_event); const char *group = event->tp_event->class->system; @@ -1626,6 +1632,8 @@ int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, *probe_addr = kallsyms_show_value(current_cred()) ? (unsigned long)tk->rp.kp.addr : 0; *symbol = tk->symbol; + if (missed) + *missed = trace_kprobe_missed(tk); return 0; } #endif /* CONFIG_PERF_EVENTS */ |