* [PATCH v2] tracing/kprobes: Add method to display private kprobes in tracefs @ 2022-07-25 6:23 Jianlin Lv 2022-09-06 15:12 ` Steven Rostedt 0 siblings, 1 reply; 5+ messages in thread From: Jianlin Lv @ 2022-07-25 6:23 UTC (permalink / raw) To: corbet, rostedt, mingo; +Cc: iecedge, jianlv, linux-kernel, linux-doc The private kprobes are not added to the global list dyn_event_list, so there is a missing interface to show probe hit and probe miss. This patch adds a profiling interface to check the number of hits or misses for private kprobes. Signed-off-by: Jianlin Lv <iecedge@gmail.com> --- v2: update commit message --- Documentation/trace/kprobetrace.rst | 6 +++- kernel/trace/trace_dynevent.c | 20 +++++++++++ kernel/trace/trace_dynevent.h | 37 ++++++++++++++++++++ kernel/trace/trace_kprobe.c | 54 +++++++++++++++++++++++++++++ 4 files changed, 116 insertions(+), 1 deletion(-) diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst index b175d88f31eb..8815d64dd8a6 100644 --- a/Documentation/trace/kprobetrace.rst +++ b/Documentation/trace/kprobetrace.rst @@ -146,7 +146,11 @@ trigger: Event Profiling --------------- You can check the total number of probe hits and probe miss-hits via -/sys/kernel/debug/tracing/kprobe_profile. +/sys/kernel/debug/tracing/kprobe_profile or +/sys/kernel/debug/tracing/kprobe_local_profile. +All kprobe events created by kprobe_events will be added to the global +list, you can get their profiling via kprobe_profile; kprobe_local_profile +shows profiling for private kprobe events created by perf_kprobe pmu. The first column is event name, the second is the number of probe hits, the third is the number of probe miss-hits. diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c index 076b447a1b88..70ec99cd9c53 100644 --- a/kernel/trace/trace_dynevent.c +++ b/kernel/trace/trace_dynevent.c @@ -181,6 +181,26 @@ static const struct seq_operations dyn_event_seq_op = { .show = dyn_event_seq_show }; +#ifdef CONFIG_KPROBE_EVENTS +LIST_HEAD(local_event_list); + +void *local_event_seq_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&event_mutex); + return seq_list_start(&local_event_list, *pos); +} + +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + return seq_list_next(v, &local_event_list, pos); +} + +void local_event_seq_stop(struct seq_file *m, void *v) +{ + mutex_unlock(&event_mutex); +} +#endif /* CONFIG_KPROBE_EVENTS */ + /* * dyn_events_release_all - Release all specific events * @type: the dyn_event_operations * which filters releasing events diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h index 936477a111d3..e30193470295 100644 --- a/kernel/trace/trace_dynevent.h +++ b/kernel/trace/trace_dynevent.h @@ -101,6 +101,43 @@ void dyn_event_seq_stop(struct seq_file *m, void *v); int dyn_events_release_all(struct dyn_event_operations *type); int dyn_event_release(const char *raw_command, struct dyn_event_operations *type); +#ifdef CONFIG_KPROBE_EVENTS +extern struct list_head local_event_list; + +static inline +int local_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) +{ + if (!ev || !ops) + return -EINVAL; + + INIT_LIST_HEAD(&ev->list); + ev->ops = ops; + return 0; +} + +static inline int local_event_add(struct dyn_event *ev) +{ + lockdep_assert_held(&event_mutex); + + if (!ev || !ev->ops) + return -EINVAL; + + list_add_tail(&ev->list, &local_event_list); + return 0; +} + +static inline void local_event_remove(struct dyn_event *ev) +{ + lockdep_assert_held(&event_mutex); + list_del_init(&ev->list); +} + +void *local_event_seq_start(struct seq_file *m, loff_t *pos); +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos); +void local_event_seq_stop(struct seq_file *m, void *v); + +#endif /* CONFIG_KPROBE_EVENTS */ + /* * for_each_dyn_event - iterate over the dyn_event list * @pos: the struct dyn_event * to use as a loop cursor diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index a245ea673715..76f500b17b46 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1213,6 +1213,52 @@ static const struct file_operations kprobe_profile_ops = { .release = seq_release, }; +#ifdef CONFIG_KPROBE_EVENTS +/* kprobe Local profile */ +static int local_probes_profile_seq_show(struct seq_file *m, void *v) +{ + struct dyn_event *ev = v; + struct trace_kprobe *tk; + + if (!is_trace_kprobe(ev)) + return 0; + + tk = to_trace_kprobe(ev); + seq_printf(m, " %-44s %15lu %15lu\n", + trace_probe_name(&tk->tp), + trace_kprobe_nhit(tk), + tk->rp.kp.nmissed); + + return 0; +} + +static const struct seq_operations local_profile_seq_op = { + .start = local_event_seq_start, + .next = local_event_seq_next, + .stop = local_event_seq_stop, + .show = local_probes_profile_seq_show +}; + +static int local_profile_open(struct inode *inode, struct file *file) +{ + int ret; + + ret = security_locked_down(LOCKDOWN_TRACEFS); + if (ret) + return ret; + + return seq_open(file, &local_profile_seq_op); +} + +static const struct file_operations kprobe_local_profile_ops = { + .owner = THIS_MODULE, + .open = local_profile_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; +#endif /* CONFIG_KPROBE_EVENTS */ + /* Kprobe specific fetch functions */ /* Return the length of string -- including null terminal byte */ @@ -1830,6 +1876,7 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, if (ret < 0) goto error; + local_event_add(&tk->devent); return trace_probe_event_call(&tk->tp); error: free_trace_kprobe(tk); @@ -1849,6 +1896,7 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call) return; } + local_event_remove(&tk->devent); __unregister_trace_kprobe(tk); free_trace_kprobe(tk); @@ -1929,6 +1977,12 @@ static __init int init_kprobe_trace(void) trace_create_file("kprobe_profile", TRACE_MODE_READ, NULL, NULL, &kprobe_profile_ops); +#ifdef CONFIG_KPROBE_EVENTS + /* kprobe Local profile */ + tracefs_create_file("kprobe_local_profile", TRACE_MODE_READ, + NULL, NULL, &kprobe_local_profile_ops); +#endif /* CONFIG_KPROBE_EVENTS */ + setup_boot_kprobe_events(); return 0; -- 2.25.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v2] tracing/kprobes: Add method to display private kprobes in tracefs 2022-07-25 6:23 [PATCH v2] tracing/kprobes: Add method to display private kprobes in tracefs Jianlin Lv @ 2022-09-06 15:12 ` Steven Rostedt 2022-09-07 8:51 ` Masami Hiramatsu 0 siblings, 1 reply; 5+ messages in thread From: Steven Rostedt @ 2022-09-06 15:12 UTC (permalink / raw) To: Jianlin Lv Cc: corbet, mingo, jianlv, linux-kernel, linux-doc, Masami Hiramatsu, Tom Zanussi [ Adding Masami and Tom ] On Mon, 25 Jul 2022 06:23:34 +0000 Jianlin Lv <iecedge@gmail.com> wrote: > The private kprobes are not added to the global list dyn_event_list, > so there is a missing interface to show probe hit and probe miss. > This patch adds a profiling interface to check the number of hits or > misses for private kprobes. Masami, what do you think of this patch? -- Steve > > Signed-off-by: Jianlin Lv <iecedge@gmail.com> > --- > v2: update commit message > --- > Documentation/trace/kprobetrace.rst | 6 +++- > kernel/trace/trace_dynevent.c | 20 +++++++++++ > kernel/trace/trace_dynevent.h | 37 ++++++++++++++++++++ > kernel/trace/trace_kprobe.c | 54 +++++++++++++++++++++++++++++ > 4 files changed, 116 insertions(+), 1 deletion(-) > > diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst > index b175d88f31eb..8815d64dd8a6 100644 > --- a/Documentation/trace/kprobetrace.rst > +++ b/Documentation/trace/kprobetrace.rst > @@ -146,7 +146,11 @@ trigger: > Event Profiling > --------------- > You can check the total number of probe hits and probe miss-hits via > -/sys/kernel/debug/tracing/kprobe_profile. > +/sys/kernel/debug/tracing/kprobe_profile or > +/sys/kernel/debug/tracing/kprobe_local_profile. > +All kprobe events created by kprobe_events will be added to the global > +list, you can get their profiling via kprobe_profile; kprobe_local_profile > +shows profiling for private kprobe events created by perf_kprobe pmu. > The first column is event name, the second is the number of probe hits, > the third is the number of probe miss-hits. > > diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c > index 076b447a1b88..70ec99cd9c53 100644 > --- a/kernel/trace/trace_dynevent.c > +++ b/kernel/trace/trace_dynevent.c > @@ -181,6 +181,26 @@ static const struct seq_operations dyn_event_seq_op = { > .show = dyn_event_seq_show > }; > > +#ifdef CONFIG_KPROBE_EVENTS > +LIST_HEAD(local_event_list); > + > +void *local_event_seq_start(struct seq_file *m, loff_t *pos) > +{ > + mutex_lock(&event_mutex); > + return seq_list_start(&local_event_list, *pos); > +} > + > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos) > +{ > + return seq_list_next(v, &local_event_list, pos); > +} > + > +void local_event_seq_stop(struct seq_file *m, void *v) > +{ > + mutex_unlock(&event_mutex); > +} > +#endif /* CONFIG_KPROBE_EVENTS */ > + > /* > * dyn_events_release_all - Release all specific events > * @type: the dyn_event_operations * which filters releasing events > diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h > index 936477a111d3..e30193470295 100644 > --- a/kernel/trace/trace_dynevent.h > +++ b/kernel/trace/trace_dynevent.h > @@ -101,6 +101,43 @@ void dyn_event_seq_stop(struct seq_file *m, void *v); > int dyn_events_release_all(struct dyn_event_operations *type); > int dyn_event_release(const char *raw_command, struct dyn_event_operations *type); > > +#ifdef CONFIG_KPROBE_EVENTS > +extern struct list_head local_event_list; > + > +static inline > +int local_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) > +{ > + if (!ev || !ops) > + return -EINVAL; > + > + INIT_LIST_HEAD(&ev->list); > + ev->ops = ops; > + return 0; > +} > + > +static inline int local_event_add(struct dyn_event *ev) > +{ > + lockdep_assert_held(&event_mutex); > + > + if (!ev || !ev->ops) > + return -EINVAL; > + > + list_add_tail(&ev->list, &local_event_list); > + return 0; > +} > + > +static inline void local_event_remove(struct dyn_event *ev) > +{ > + lockdep_assert_held(&event_mutex); > + list_del_init(&ev->list); > +} > + > +void *local_event_seq_start(struct seq_file *m, loff_t *pos); > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos); > +void local_event_seq_stop(struct seq_file *m, void *v); > + > +#endif /* CONFIG_KPROBE_EVENTS */ > + > /* > * for_each_dyn_event - iterate over the dyn_event list > * @pos: the struct dyn_event * to use as a loop cursor > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index a245ea673715..76f500b17b46 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -1213,6 +1213,52 @@ static const struct file_operations kprobe_profile_ops = { > .release = seq_release, > }; > > +#ifdef CONFIG_KPROBE_EVENTS > +/* kprobe Local profile */ > +static int local_probes_profile_seq_show(struct seq_file *m, void *v) > +{ > + struct dyn_event *ev = v; > + struct trace_kprobe *tk; > + > + if (!is_trace_kprobe(ev)) > + return 0; > + > + tk = to_trace_kprobe(ev); > + seq_printf(m, " %-44s %15lu %15lu\n", > + trace_probe_name(&tk->tp), > + trace_kprobe_nhit(tk), > + tk->rp.kp.nmissed); > + > + return 0; > +} > + > +static const struct seq_operations local_profile_seq_op = { > + .start = local_event_seq_start, > + .next = local_event_seq_next, > + .stop = local_event_seq_stop, > + .show = local_probes_profile_seq_show > +}; > + > +static int local_profile_open(struct inode *inode, struct file *file) > +{ > + int ret; > + > + ret = security_locked_down(LOCKDOWN_TRACEFS); > + if (ret) > + return ret; > + > + return seq_open(file, &local_profile_seq_op); > +} > + > +static const struct file_operations kprobe_local_profile_ops = { > + .owner = THIS_MODULE, > + .open = local_profile_open, > + .read = seq_read, > + .llseek = seq_lseek, > + .release = seq_release, > +}; > +#endif /* CONFIG_KPROBE_EVENTS */ > + > /* Kprobe specific fetch functions */ > > /* Return the length of string -- including null terminal byte */ > @@ -1830,6 +1876,7 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, > if (ret < 0) > goto error; > > + local_event_add(&tk->devent); > return trace_probe_event_call(&tk->tp); > error: > free_trace_kprobe(tk); > @@ -1849,6 +1896,7 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call) > return; > } > > + local_event_remove(&tk->devent); > __unregister_trace_kprobe(tk); > > free_trace_kprobe(tk); > @@ -1929,6 +1977,12 @@ static __init int init_kprobe_trace(void) > trace_create_file("kprobe_profile", TRACE_MODE_READ, > NULL, NULL, &kprobe_profile_ops); > > +#ifdef CONFIG_KPROBE_EVENTS > + /* kprobe Local profile */ > + tracefs_create_file("kprobe_local_profile", TRACE_MODE_READ, > + NULL, NULL, &kprobe_local_profile_ops); > +#endif /* CONFIG_KPROBE_EVENTS */ > + > setup_boot_kprobe_events(); > > return 0; ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] tracing/kprobes: Add method to display private kprobes in tracefs 2022-09-06 15:12 ` Steven Rostedt @ 2022-09-07 8:51 ` Masami Hiramatsu 2022-09-09 1:26 ` Jianlin Lv 0 siblings, 1 reply; 5+ messages in thread From: Masami Hiramatsu @ 2022-09-07 8:51 UTC (permalink / raw) To: Steven Rostedt Cc: Jianlin Lv, corbet, mingo, jianlv, linux-kernel, linux-doc, Masami Hiramatsu, Tom Zanussi, bpf [Adding bpf ML] On Tue, 6 Sep 2022 11:12:14 -0400 Steven Rostedt <rostedt@goodmis.org> wrote: > > [ Adding Masami and Tom ] > > On Mon, 25 Jul 2022 06:23:34 +0000 > Jianlin Lv <iecedge@gmail.com> wrote: > > > The private kprobes are not added to the global list dyn_event_list, > > so there is a missing interface to show probe hit and probe miss. > > This patch adds a profiling interface to check the number of hits or > > misses for private kprobes. > > Masami, what do you think of this patch? I discussed it with BPF people when it was introduced and they didn't want to show up it on tracefs because it is a private one. I agreed that. So I think this kind of interface must be managed by BPF subsystem. Is there any API to manage the BPF probe points in BPF subsystem? Thank you, > > -- Steve > > > > > Signed-off-by: Jianlin Lv <iecedge@gmail.com> > > --- > > v2: update commit message > > --- > > Documentation/trace/kprobetrace.rst | 6 +++- > > kernel/trace/trace_dynevent.c | 20 +++++++++++ > > kernel/trace/trace_dynevent.h | 37 ++++++++++++++++++++ > > kernel/trace/trace_kprobe.c | 54 +++++++++++++++++++++++++++++ > > 4 files changed, 116 insertions(+), 1 deletion(-) > > > > diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst > > index b175d88f31eb..8815d64dd8a6 100644 > > --- a/Documentation/trace/kprobetrace.rst > > +++ b/Documentation/trace/kprobetrace.rst > > @@ -146,7 +146,11 @@ trigger: > > Event Profiling > > --------------- > > You can check the total number of probe hits and probe miss-hits via > > -/sys/kernel/debug/tracing/kprobe_profile. > > +/sys/kernel/debug/tracing/kprobe_profile or > > +/sys/kernel/debug/tracing/kprobe_local_profile. > > +All kprobe events created by kprobe_events will be added to the global > > +list, you can get their profiling via kprobe_profile; kprobe_local_profile > > +shows profiling for private kprobe events created by perf_kprobe pmu. > > The first column is event name, the second is the number of probe hits, > > the third is the number of probe miss-hits. > > > > diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c > > index 076b447a1b88..70ec99cd9c53 100644 > > --- a/kernel/trace/trace_dynevent.c > > +++ b/kernel/trace/trace_dynevent.c > > @@ -181,6 +181,26 @@ static const struct seq_operations dyn_event_seq_op = { > > .show = dyn_event_seq_show > > }; > > > > +#ifdef CONFIG_KPROBE_EVENTS > > +LIST_HEAD(local_event_list); > > + > > +void *local_event_seq_start(struct seq_file *m, loff_t *pos) > > +{ > > + mutex_lock(&event_mutex); > > + return seq_list_start(&local_event_list, *pos); > > +} > > + > > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos) > > +{ > > + return seq_list_next(v, &local_event_list, pos); > > +} > > + > > +void local_event_seq_stop(struct seq_file *m, void *v) > > +{ > > + mutex_unlock(&event_mutex); > > +} > > +#endif /* CONFIG_KPROBE_EVENTS */ > > + > > /* > > * dyn_events_release_all - Release all specific events > > * @type: the dyn_event_operations * which filters releasing events > > diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h > > index 936477a111d3..e30193470295 100644 > > --- a/kernel/trace/trace_dynevent.h > > +++ b/kernel/trace/trace_dynevent.h > > @@ -101,6 +101,43 @@ void dyn_event_seq_stop(struct seq_file *m, void *v); > > int dyn_events_release_all(struct dyn_event_operations *type); > > int dyn_event_release(const char *raw_command, struct dyn_event_operations *type); > > > > +#ifdef CONFIG_KPROBE_EVENTS > > +extern struct list_head local_event_list; > > + > > +static inline > > +int local_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) > > +{ > > + if (!ev || !ops) > > + return -EINVAL; > > + > > + INIT_LIST_HEAD(&ev->list); > > + ev->ops = ops; > > + return 0; > > +} > > + > > +static inline int local_event_add(struct dyn_event *ev) > > +{ > > + lockdep_assert_held(&event_mutex); > > + > > + if (!ev || !ev->ops) > > + return -EINVAL; > > + > > + list_add_tail(&ev->list, &local_event_list); > > + return 0; > > +} > > + > > +static inline void local_event_remove(struct dyn_event *ev) > > +{ > > + lockdep_assert_held(&event_mutex); > > + list_del_init(&ev->list); > > +} > > + > > +void *local_event_seq_start(struct seq_file *m, loff_t *pos); > > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos); > > +void local_event_seq_stop(struct seq_file *m, void *v); > > + > > +#endif /* CONFIG_KPROBE_EVENTS */ > > + > > /* > > * for_each_dyn_event - iterate over the dyn_event list > > * @pos: the struct dyn_event * to use as a loop cursor > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > > index a245ea673715..76f500b17b46 100644 > > --- a/kernel/trace/trace_kprobe.c > > +++ b/kernel/trace/trace_kprobe.c > > @@ -1213,6 +1213,52 @@ static const struct file_operations kprobe_profile_ops = { > > .release = seq_release, > > }; > > > > +#ifdef CONFIG_KPROBE_EVENTS > > +/* kprobe Local profile */ > > +static int local_probes_profile_seq_show(struct seq_file *m, void *v) > > +{ > > + struct dyn_event *ev = v; > > + struct trace_kprobe *tk; > > + > > + if (!is_trace_kprobe(ev)) > > + return 0; > > + > > + tk = to_trace_kprobe(ev); > > + seq_printf(m, " %-44s %15lu %15lu\n", > > + trace_probe_name(&tk->tp), > > + trace_kprobe_nhit(tk), > > + tk->rp.kp.nmissed); > > + > > + return 0; > > +} > > + > > +static const struct seq_operations local_profile_seq_op = { > > + .start = local_event_seq_start, > > + .next = local_event_seq_next, > > + .stop = local_event_seq_stop, > > + .show = local_probes_profile_seq_show > > +}; > > + > > +static int local_profile_open(struct inode *inode, struct file *file) > > +{ > > + int ret; > > + > > + ret = security_locked_down(LOCKDOWN_TRACEFS); > > + if (ret) > > + return ret; > > + > > + return seq_open(file, &local_profile_seq_op); > > +} > > + > > +static const struct file_operations kprobe_local_profile_ops = { > > + .owner = THIS_MODULE, > > + .open = local_profile_open, > > + .read = seq_read, > > + .llseek = seq_lseek, > > + .release = seq_release, > > +}; > > +#endif /* CONFIG_KPROBE_EVENTS */ > > + > > /* Kprobe specific fetch functions */ > > > > /* Return the length of string -- including null terminal byte */ > > @@ -1830,6 +1876,7 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, > > if (ret < 0) > > goto error; > > > > + local_event_add(&tk->devent); > > return trace_probe_event_call(&tk->tp); > > error: > > free_trace_kprobe(tk); > > @@ -1849,6 +1896,7 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call) > > return; > > } > > > > + local_event_remove(&tk->devent); > > __unregister_trace_kprobe(tk); > > > > free_trace_kprobe(tk); > > @@ -1929,6 +1977,12 @@ static __init int init_kprobe_trace(void) > > trace_create_file("kprobe_profile", TRACE_MODE_READ, > > NULL, NULL, &kprobe_profile_ops); > > > > +#ifdef CONFIG_KPROBE_EVENTS > > + /* kprobe Local profile */ > > + tracefs_create_file("kprobe_local_profile", TRACE_MODE_READ, > > + NULL, NULL, &kprobe_local_profile_ops); > > +#endif /* CONFIG_KPROBE_EVENTS */ > > + > > setup_boot_kprobe_events(); > > > > return 0; > -- Masami Hiramatsu (Google) <mhiramat@kernel.org> ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] tracing/kprobes: Add method to display private kprobes in tracefs 2022-09-07 8:51 ` Masami Hiramatsu @ 2022-09-09 1:26 ` Jianlin Lv 2022-09-09 11:05 ` Masami Hiramatsu 0 siblings, 1 reply; 5+ messages in thread From: Jianlin Lv @ 2022-09-09 1:26 UTC (permalink / raw) To: Masami Hiramatsu Cc: Steven Rostedt, corbet, mingo, jianlv, linux-kernel, linux-doc, Tom Zanussi, bpf On Wed, Sep 7, 2022 at 4:51 PM Masami Hiramatsu <mhiramat@kernel.org> wrote: > > [Adding bpf ML] > > On Tue, 6 Sep 2022 11:12:14 -0400 > Steven Rostedt <rostedt@goodmis.org> wrote: > > > > > [ Adding Masami and Tom ] > > > > On Mon, 25 Jul 2022 06:23:34 +0000 > > Jianlin Lv <iecedge@gmail.com> wrote: > > > > > The private kprobes are not added to the global list dyn_event_list, > > > so there is a missing interface to show probe hit and probe miss. > > > This patch adds a profiling interface to check the number of hits or > > > misses for private kprobes. > > > > Masami, what do you think of this patch? > > I discussed it with BPF people when it was introduced and they didn't > want to show up it on tracefs because it is a private one. I agreed that. > > So I think this kind of interface must be managed by BPF subsystem. > Is there any API to manage the BPF probe points in BPF subsystem? > > Thank you, As far as I know, there is no API to manage private kprobes in the BPF subsystem, so I added a tracefs interface to display private info. Could you give me some hints about how to implement the current functionality in the BPF subsystem? Regards, Jianlin > > > > > -- Steve > > > > > > > > Signed-off-by: Jianlin Lv <iecedge@gmail.com> > > > --- > > > v2: update commit message > > > --- > > > Documentation/trace/kprobetrace.rst | 6 +++- > > > kernel/trace/trace_dynevent.c | 20 +++++++++++ > > > kernel/trace/trace_dynevent.h | 37 ++++++++++++++++++++ > > > kernel/trace/trace_kprobe.c | 54 +++++++++++++++++++++++++++++ > > > 4 files changed, 116 insertions(+), 1 deletion(-) > > > > > > diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst > > > index b175d88f31eb..8815d64dd8a6 100644 > > > --- a/Documentation/trace/kprobetrace.rst > > > +++ b/Documentation/trace/kprobetrace.rst > > > @@ -146,7 +146,11 @@ trigger: > > > Event Profiling > > > --------------- > > > You can check the total number of probe hits and probe miss-hits via > > > -/sys/kernel/debug/tracing/kprobe_profile. > > > +/sys/kernel/debug/tracing/kprobe_profile or > > > +/sys/kernel/debug/tracing/kprobe_local_profile. > > > +All kprobe events created by kprobe_events will be added to the global > > > +list, you can get their profiling via kprobe_profile; kprobe_local_profile > > > +shows profiling for private kprobe events created by perf_kprobe pmu. > > > The first column is event name, the second is the number of probe hits, > > > the third is the number of probe miss-hits. > > > > > > diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c > > > index 076b447a1b88..70ec99cd9c53 100644 > > > --- a/kernel/trace/trace_dynevent.c > > > +++ b/kernel/trace/trace_dynevent.c > > > @@ -181,6 +181,26 @@ static const struct seq_operations dyn_event_seq_op = { > > > .show = dyn_event_seq_show > > > }; > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > +LIST_HEAD(local_event_list); > > > + > > > +void *local_event_seq_start(struct seq_file *m, loff_t *pos) > > > +{ > > > + mutex_lock(&event_mutex); > > > + return seq_list_start(&local_event_list, *pos); > > > +} > > > + > > > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos) > > > +{ > > > + return seq_list_next(v, &local_event_list, pos); > > > +} > > > + > > > +void local_event_seq_stop(struct seq_file *m, void *v) > > > +{ > > > + mutex_unlock(&event_mutex); > > > +} > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > + > > > /* > > > * dyn_events_release_all - Release all specific events > > > * @type: the dyn_event_operations * which filters releasing events > > > diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h > > > index 936477a111d3..e30193470295 100644 > > > --- a/kernel/trace/trace_dynevent.h > > > +++ b/kernel/trace/trace_dynevent.h > > > @@ -101,6 +101,43 @@ void dyn_event_seq_stop(struct seq_file *m, void *v); > > > int dyn_events_release_all(struct dyn_event_operations *type); > > > int dyn_event_release(const char *raw_command, struct dyn_event_operations *type); > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > +extern struct list_head local_event_list; > > > + > > > +static inline > > > +int local_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) > > > +{ > > > + if (!ev || !ops) > > > + return -EINVAL; > > > + > > > + INIT_LIST_HEAD(&ev->list); > > > + ev->ops = ops; > > > + return 0; > > > +} > > > + > > > +static inline int local_event_add(struct dyn_event *ev) > > > +{ > > > + lockdep_assert_held(&event_mutex); > > > + > > > + if (!ev || !ev->ops) > > > + return -EINVAL; > > > + > > > + list_add_tail(&ev->list, &local_event_list); > > > + return 0; > > > +} > > > + > > > +static inline void local_event_remove(struct dyn_event *ev) > > > +{ > > > + lockdep_assert_held(&event_mutex); > > > + list_del_init(&ev->list); > > > +} > > > + > > > +void *local_event_seq_start(struct seq_file *m, loff_t *pos); > > > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos); > > > +void local_event_seq_stop(struct seq_file *m, void *v); > > > + > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > + > > > /* > > > * for_each_dyn_event - iterate over the dyn_event list > > > * @pos: the struct dyn_event * to use as a loop cursor > > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > > > index a245ea673715..76f500b17b46 100644 > > > --- a/kernel/trace/trace_kprobe.c > > > +++ b/kernel/trace/trace_kprobe.c > > > @@ -1213,6 +1213,52 @@ static const struct file_operations kprobe_profile_ops = { > > > .release = seq_release, > > > }; > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > +/* kprobe Local profile */ > > > +static int local_probes_profile_seq_show(struct seq_file *m, void *v) > > > +{ > > > + struct dyn_event *ev = v; > > > + struct trace_kprobe *tk; > > > + > > > + if (!is_trace_kprobe(ev)) > > > + return 0; > > > + > > > + tk = to_trace_kprobe(ev); > > > + seq_printf(m, " %-44s %15lu %15lu\n", > > > + trace_probe_name(&tk->tp), > > > + trace_kprobe_nhit(tk), > > > + tk->rp.kp.nmissed); > > > + > > > + return 0; > > > +} > > > + > > > +static const struct seq_operations local_profile_seq_op = { > > > + .start = local_event_seq_start, > > > + .next = local_event_seq_next, > > > + .stop = local_event_seq_stop, > > > + .show = local_probes_profile_seq_show > > > +}; > > > + > > > +static int local_profile_open(struct inode *inode, struct file *file) > > > +{ > > > + int ret; > > > + > > > + ret = security_locked_down(LOCKDOWN_TRACEFS); > > > + if (ret) > > > + return ret; > > > + > > > + return seq_open(file, &local_profile_seq_op); > > > +} > > > + > > > +static const struct file_operations kprobe_local_profile_ops = { > > > + .owner = THIS_MODULE, > > > + .open = local_profile_open, > > > + .read = seq_read, > > > + .llseek = seq_lseek, > > > + .release = seq_release, > > > +}; > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > + > > > /* Kprobe specific fetch functions */ > > > > > > /* Return the length of string -- including null terminal byte */ > > > @@ -1830,6 +1876,7 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, > > > if (ret < 0) > > > goto error; > > > > > > + local_event_add(&tk->devent); > > > return trace_probe_event_call(&tk->tp); > > > error: > > > free_trace_kprobe(tk); > > > @@ -1849,6 +1896,7 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call) > > > return; > > > } > > > > > > + local_event_remove(&tk->devent); > > > __unregister_trace_kprobe(tk); > > > > > > free_trace_kprobe(tk); > > > @@ -1929,6 +1977,12 @@ static __init int init_kprobe_trace(void) > > > trace_create_file("kprobe_profile", TRACE_MODE_READ, > > > NULL, NULL, &kprobe_profile_ops); > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > + /* kprobe Local profile */ > > > + tracefs_create_file("kprobe_local_profile", TRACE_MODE_READ, > > > + NULL, NULL, &kprobe_local_profile_ops); > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > + > > > setup_boot_kprobe_events(); > > > > > > return 0; > > > > > -- > Masami Hiramatsu (Google) <mhiramat@kernel.org> ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] tracing/kprobes: Add method to display private kprobes in tracefs 2022-09-09 1:26 ` Jianlin Lv @ 2022-09-09 11:05 ` Masami Hiramatsu 0 siblings, 0 replies; 5+ messages in thread From: Masami Hiramatsu @ 2022-09-09 11:05 UTC (permalink / raw) To: Jianlin Lv Cc: Steven Rostedt, corbet, mingo, jianlv, linux-kernel, linux-doc, Tom Zanussi, bpf On Fri, 9 Sep 2022 09:26:23 +0800 Jianlin Lv <iecedge@gmail.com> wrote: > On Wed, Sep 7, 2022 at 4:51 PM Masami Hiramatsu <mhiramat@kernel.org> wrote: > > > > [Adding bpf ML] > > > > On Tue, 6 Sep 2022 11:12:14 -0400 > > Steven Rostedt <rostedt@goodmis.org> wrote: > > > > > > > > [ Adding Masami and Tom ] > > > > > > On Mon, 25 Jul 2022 06:23:34 +0000 > > > Jianlin Lv <iecedge@gmail.com> wrote: > > > > > > > The private kprobes are not added to the global list dyn_event_list, > > > > so there is a missing interface to show probe hit and probe miss. > > > > This patch adds a profiling interface to check the number of hits or > > > > misses for private kprobes. > > > > > > Masami, what do you think of this patch? > > > > I discussed it with BPF people when it was introduced and they didn't > > want to show up it on tracefs because it is a private one. I agreed that. > > > > So I think this kind of interface must be managed by BPF subsystem. > > Is there any API to manage the BPF probe points in BPF subsystem? > > > > Thank you, > > As far as I know, there is no API to manage private kprobes in the BPF > subsystem, so I added a tracefs interface to display private info. > > Could you give me some hints about how to implement the current > functionality in the BPF subsystem? There is tools/bpf/bpftool, I think that is the best tool to implement such feature. If hitcount is shown with the BPF program, it should be more useful. Thank you, > > Regards, > Jianlin > > > > > > > > > -- Steve > > > > > > > > > > > Signed-off-by: Jianlin Lv <iecedge@gmail.com> > > > > --- > > > > v2: update commit message > > > > --- > > > > Documentation/trace/kprobetrace.rst | 6 +++- > > > > kernel/trace/trace_dynevent.c | 20 +++++++++++ > > > > kernel/trace/trace_dynevent.h | 37 ++++++++++++++++++++ > > > > kernel/trace/trace_kprobe.c | 54 +++++++++++++++++++++++++++++ > > > > 4 files changed, 116 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst > > > > index b175d88f31eb..8815d64dd8a6 100644 > > > > --- a/Documentation/trace/kprobetrace.rst > > > > +++ b/Documentation/trace/kprobetrace.rst > > > > @@ -146,7 +146,11 @@ trigger: > > > > Event Profiling > > > > --------------- > > > > You can check the total number of probe hits and probe miss-hits via > > > > -/sys/kernel/debug/tracing/kprobe_profile. > > > > +/sys/kernel/debug/tracing/kprobe_profile or > > > > +/sys/kernel/debug/tracing/kprobe_local_profile. > > > > +All kprobe events created by kprobe_events will be added to the global > > > > +list, you can get their profiling via kprobe_profile; kprobe_local_profile > > > > +shows profiling for private kprobe events created by perf_kprobe pmu. > > > > The first column is event name, the second is the number of probe hits, > > > > the third is the number of probe miss-hits. > > > > > > > > diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c > > > > index 076b447a1b88..70ec99cd9c53 100644 > > > > --- a/kernel/trace/trace_dynevent.c > > > > +++ b/kernel/trace/trace_dynevent.c > > > > @@ -181,6 +181,26 @@ static const struct seq_operations dyn_event_seq_op = { > > > > .show = dyn_event_seq_show > > > > }; > > > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > > +LIST_HEAD(local_event_list); > > > > + > > > > +void *local_event_seq_start(struct seq_file *m, loff_t *pos) > > > > +{ > > > > + mutex_lock(&event_mutex); > > > > + return seq_list_start(&local_event_list, *pos); > > > > +} > > > > + > > > > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos) > > > > +{ > > > > + return seq_list_next(v, &local_event_list, pos); > > > > +} > > > > + > > > > +void local_event_seq_stop(struct seq_file *m, void *v) > > > > +{ > > > > + mutex_unlock(&event_mutex); > > > > +} > > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > > + > > > > /* > > > > * dyn_events_release_all - Release all specific events > > > > * @type: the dyn_event_operations * which filters releasing events > > > > diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h > > > > index 936477a111d3..e30193470295 100644 > > > > --- a/kernel/trace/trace_dynevent.h > > > > +++ b/kernel/trace/trace_dynevent.h > > > > @@ -101,6 +101,43 @@ void dyn_event_seq_stop(struct seq_file *m, void *v); > > > > int dyn_events_release_all(struct dyn_event_operations *type); > > > > int dyn_event_release(const char *raw_command, struct dyn_event_operations *type); > > > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > > +extern struct list_head local_event_list; > > > > + > > > > +static inline > > > > +int local_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) > > > > +{ > > > > + if (!ev || !ops) > > > > + return -EINVAL; > > > > + > > > > + INIT_LIST_HEAD(&ev->list); > > > > + ev->ops = ops; > > > > + return 0; > > > > +} > > > > + > > > > +static inline int local_event_add(struct dyn_event *ev) > > > > +{ > > > > + lockdep_assert_held(&event_mutex); > > > > + > > > > + if (!ev || !ev->ops) > > > > + return -EINVAL; > > > > + > > > > + list_add_tail(&ev->list, &local_event_list); > > > > + return 0; > > > > +} > > > > + > > > > +static inline void local_event_remove(struct dyn_event *ev) > > > > +{ > > > > + lockdep_assert_held(&event_mutex); > > > > + list_del_init(&ev->list); > > > > +} > > > > + > > > > +void *local_event_seq_start(struct seq_file *m, loff_t *pos); > > > > +void *local_event_seq_next(struct seq_file *m, void *v, loff_t *pos); > > > > +void local_event_seq_stop(struct seq_file *m, void *v); > > > > + > > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > > + > > > > /* > > > > * for_each_dyn_event - iterate over the dyn_event list > > > > * @pos: the struct dyn_event * to use as a loop cursor > > > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > > > > index a245ea673715..76f500b17b46 100644 > > > > --- a/kernel/trace/trace_kprobe.c > > > > +++ b/kernel/trace/trace_kprobe.c > > > > @@ -1213,6 +1213,52 @@ static const struct file_operations kprobe_profile_ops = { > > > > .release = seq_release, > > > > }; > > > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > > +/* kprobe Local profile */ > > > > +static int local_probes_profile_seq_show(struct seq_file *m, void *v) > > > > +{ > > > > + struct dyn_event *ev = v; > > > > + struct trace_kprobe *tk; > > > > + > > > > + if (!is_trace_kprobe(ev)) > > > > + return 0; > > > > + > > > > + tk = to_trace_kprobe(ev); > > > > + seq_printf(m, " %-44s %15lu %15lu\n", > > > > + trace_probe_name(&tk->tp), > > > > + trace_kprobe_nhit(tk), > > > > + tk->rp.kp.nmissed); > > > > + > > > > + return 0; > > > > +} > > > > + > > > > +static const struct seq_operations local_profile_seq_op = { > > > > + .start = local_event_seq_start, > > > > + .next = local_event_seq_next, > > > > + .stop = local_event_seq_stop, > > > > + .show = local_probes_profile_seq_show > > > > +}; > > > > + > > > > +static int local_profile_open(struct inode *inode, struct file *file) > > > > +{ > > > > + int ret; > > > > + > > > > + ret = security_locked_down(LOCKDOWN_TRACEFS); > > > > + if (ret) > > > > + return ret; > > > > + > > > > + return seq_open(file, &local_profile_seq_op); > > > > +} > > > > + > > > > +static const struct file_operations kprobe_local_profile_ops = { > > > > + .owner = THIS_MODULE, > > > > + .open = local_profile_open, > > > > + .read = seq_read, > > > > + .llseek = seq_lseek, > > > > + .release = seq_release, > > > > +}; > > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > > + > > > > /* Kprobe specific fetch functions */ > > > > > > > > /* Return the length of string -- including null terminal byte */ > > > > @@ -1830,6 +1876,7 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, > > > > if (ret < 0) > > > > goto error; > > > > > > > > + local_event_add(&tk->devent); > > > > return trace_probe_event_call(&tk->tp); > > > > error: > > > > free_trace_kprobe(tk); > > > > @@ -1849,6 +1896,7 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call) > > > > return; > > > > } > > > > > > > > + local_event_remove(&tk->devent); > > > > __unregister_trace_kprobe(tk); > > > > > > > > free_trace_kprobe(tk); > > > > @@ -1929,6 +1977,12 @@ static __init int init_kprobe_trace(void) > > > > trace_create_file("kprobe_profile", TRACE_MODE_READ, > > > > NULL, NULL, &kprobe_profile_ops); > > > > > > > > +#ifdef CONFIG_KPROBE_EVENTS > > > > + /* kprobe Local profile */ > > > > + tracefs_create_file("kprobe_local_profile", TRACE_MODE_READ, > > > > + NULL, NULL, &kprobe_local_profile_ops); > > > > +#endif /* CONFIG_KPROBE_EVENTS */ > > > > + > > > > setup_boot_kprobe_events(); > > > > > > > > return 0; > > > > > > > > > -- > > Masami Hiramatsu (Google) <mhiramat@kernel.org> -- Masami Hiramatsu (Google) <mhiramat@kernel.org> ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-09-09 11:05 UTC | newest] Thread overview: 5+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2022-07-25 6:23 [PATCH v2] tracing/kprobes: Add method to display private kprobes in tracefs Jianlin Lv 2022-09-06 15:12 ` Steven Rostedt 2022-09-07 8:51 ` Masami Hiramatsu 2022-09-09 1:26 ` Jianlin Lv 2022-09-09 11:05 ` Masami Hiramatsu
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