On 15/10/2024 8:11 pm, Steven Rostedt wrote:
From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx> The function tracefs_dynevent_get_all() will only look at the dynamic_events file if it exists to find matching probes. But because uprobes and kprobes both use the same prefix "p" as well as uretprobes and kretprobes (with prefix "r"), it cannot use the dynamic_events file to differentiate between the two. Have kprobes and uprobes always use their own files (kprobe_events and uprobe_events) even if dynamic_events file exists. Also cleaned up the code to be a bit more efficient. Link: https://lore.kernel.org/all/20241015123831.347ff0f4@xxxxxxxxxxxxxxxxxx/ Fixes: b04f18b005c6b ("libtracefs: New APIs for dynamic events") Reported-by: Metin Kaya <metin.kaya@xxxxxxx> Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> --- src/tracefs-dynevents.c | 113 +++++++++++++++++++++------------------- 1 file changed, 60 insertions(+), 53 deletions(-) diff --git a/src/tracefs-dynevents.c b/src/tracefs-dynevents.c index 85c1fcd9d5d5..6b9ba539fde3 100644 --- a/src/tracefs-dynevents.c +++ b/src/tracefs-dynevents.c @@ -34,23 +34,21 @@ static int dyn_generic_del(struct dyn_events_desc *, struct tracefs_dynevent *); static int dyn_synth_del(struct dyn_events_desc *, struct tracefs_dynevent *);struct dyn_events_desc {- enum tracefs_dynevent_type type; - const char *file; - const char *prefix; + enum tracefs_dynevent_type type; + const char *file; + const char *prefix; int (*del)(struct dyn_events_desc *desc, struct tracefs_dynevent *dyn); int (*parse)(struct dyn_events_desc *desc, const char *group, char *line, struct tracefs_dynevent **ret_dyn); } dynevents[] = { - {TRACEFS_DYNEVENT_KPROBE, KPROBE_EVENTS, "p", dyn_generic_del, dyn_generic_parse}, + {TRACEFS_DYNEVENT_KPROBE, KPROBE_EVENTS, "p", dyn_generic_del, dyn_generic_parse}, {TRACEFS_DYNEVENT_KRETPROBE, KPROBE_EVENTS, "r", dyn_generic_del, dyn_generic_parse}, - {TRACEFS_DYNEVENT_UPROBE, UPROBE_EVENTS, "p", dyn_generic_del, dyn_generic_parse}, + {TRACEFS_DYNEVENT_UPROBE, UPROBE_EVENTS, "p", dyn_generic_del, dyn_generic_parse}, {TRACEFS_DYNEVENT_URETPROBE, UPROBE_EVENTS, "r", dyn_generic_del, dyn_generic_parse}, - {TRACEFS_DYNEVENT_EPROBE, "", "e", dyn_generic_del, dyn_generic_parse}, - {TRACEFS_DYNEVENT_SYNTH, SYNTH_EVENTS, "", dyn_synth_del, dyn_synth_parse}, + {TRACEFS_DYNEVENT_EPROBE, "", "e", dyn_generic_del, dyn_generic_parse}, + {TRACEFS_DYNEVENT_SYNTH, SYNTH_EVENTS, "", dyn_synth_del, dyn_synth_parse}, };-- static int dyn_generic_del(struct dyn_events_desc *desc, struct tracefs_dynevent *dyn) { char *str; @@ -280,8 +278,13 @@ static void init_devent_desc(void) return;/* Use ftrace dynamic_events, if available */- for (i = 0; i < EVENT_INDEX(TRACEFS_DYNEVENT_MAX); i++) + for (i = 0; i < EVENT_INDEX(TRACEFS_DYNEVENT_MAX); i++) { + /* kprobes and uprobes do not use default file */ + if (dynevents[i].prefix[0] == 'p' || + dynevents[i].prefix[0] == 'r') + continue; dynevents[i].file = DYNEVENTS_EVENTS; + }dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].prefix = "s";} @@ -480,16 +483,15 @@ int tracefs_dynevent_destroy(struct tracefs_dynevent *devent, bool force) return desc->del(desc, devent); }-static int get_all_dynevents(enum tracefs_dynevent_type type, const char *system,- struct tracefs_dynevent ***ret_all) +static int get_dynevent(enum tracefs_dynevent_type type, const char *system, + struct tracefs_dynevent ***ret_all, int count) { struct dyn_events_desc *desc; - struct tracefs_dynevent *devent, **tmp, **all = NULL; + struct tracefs_dynevent *devent, **tmp, **all; char *content; - int count = 0; char *line; char *next; - int ret; + int ret = -1;desc = get_devent_desc(type);if (!desc) @@ -499,6 +501,9 @@ static int get_all_dynevents(enum tracefs_dynevent_type type, const char *system if (!content) return -1;+ if (ret_all)+ all = *ret_all; + line = content; do { next = strchr(line, '\n'); @@ -507,11 +512,12 @@ static int get_all_dynevents(enum tracefs_dynevent_type type, const char *system ret = desc->parse(desc, system, line, ret_all ? &devent : NULL); if (!ret) { if (ret_all) { - tmp = realloc(all, (count + 1) * sizeof(*tmp)); + tmp = realloc(all, (count + 2) * sizeof(*tmp)); if (!tmp) - goto error; + break; all = tmp; all[count] = devent; + all[count + 1] = NULL; } count++; } @@ -521,12 +527,38 @@ static int get_all_dynevents(enum tracefs_dynevent_type type, const char *system free(content); if (ret_all) *ret_all = all; + return count; +}-error:- free(content); - free(all); - return -1; +static int get_all_dynevents(enum tracefs_dynevent_type type, const char *system, + struct tracefs_dynevent ***ret_all) +{ + int count = 0; + int i; + + if (ret_all) + *ret_all = NULL; + + for (i = 0; i < EVENT_INDEX(TRACEFS_DYNEVENT_MAX); i++) { + if (!((1 << i) & type)) + continue; + + count = get_dynevent((1 << i), system, ret_all, count); + if (count < 0) { + count = 0; + break; + } + } + + if (!count) { + if (ret_all) { + free(*ret_all); + *ret_all = NULL; + } + count = -1; + } + return count; }/**@@ -561,41 +593,16 @@ void tracefs_dynevent_list_free(struct tracefs_dynevent **events) struct tracefs_dynevent ** tracefs_dynevent_get_all(unsigned int types, const char *system) { - struct tracefs_dynevent **events, **tmp, **all_events = NULL; - int count, all = 0; - int i; + struct tracefs_dynevent **events; + int count;- for (i = 1; i < TRACEFS_DYNEVENT_MAX; i <<= 1) {- if (types) { - if (i > types) - break; - if (!(types & i)) - continue; - } - count = get_all_dynevents(i, system, &events); - if (count > 0) { - tmp = realloc(all_events, (all + count + 1) * sizeof(*tmp)); - if (!tmp) - goto error; - all_events = tmp; - memcpy(all_events + all, events, count * sizeof(*events)); - all += count; - /* Add a NULL pointer at the end */ - all_events[all] = NULL; - free(events); - } + count = get_all_dynevents(types, system, &events); + if (count <= 0) { + free(events); + return NULL; }- return all_events;- -error: - free(events); - if (all_events) { - for (i = 0; i < all; i++) - free(all_events[i]); - free(all_events); - } - return NULL; + return events; }/**
I could successfully apply the patch on 4cbebed79b1f ("libtracefs: Documentation: Add missing documentation to meson.build").
The unit tests at [1] passes with this patch.Just for the records, there are some unit test failures in libtracefs (they were there even before the patch):
$ sudo ./utest/trace-utest
CUnit - A unit testing framework for C - Version 2.1-3
http://cunit.sourceforge.net/
Memory mapped buffers not supported
Suite: tracefs library
Test: Test tracefs/debugfs mounting ...FAILED
1. tracefs-utest.c:1806 - ret == 0
Test: trace cpu read ...passed
Test: trace cpu read_buf_percent ...passed
Test: trace cpu pipe ...passed
Test: trace pid events filter ...passed
Test: trace pid function filter ...passed
Test: trace sql ...passed
Test: trace sql trace onmax ...passed
Test: trace sql trace onchange ...passed
Test: trace sql snapshot onmax ...passed
Test: trace sql snapshot onchange ...passed
Test: trace sql save onmax ...passed
Test: trace sql save onchange ...passed
Test: trace sql trace and snapshot onmax ...passed
Test: trace sql trace and snapshot onchange ...passed
Test: tracing file / directory APIs ...passed
Test: instance file / directory APIs ...passed
Test: instance file descriptor ...passed
Test: instance reset ...passed
Test: systems and events APIs ...passed
Test: tracefs_iterate_snapshot_events API ...passed
Test: tracefs_iterate_raw_events API ...FAILED
1. tracefs-utest.c:235 - ret == sizeof(struct test_sample)
2. tracefs-utest.c:235 - ret == sizeof(struct test_sample)
Test: Follow events ...passed
Test: Follow events clear ...passed
Test: tracefs_tracers API ...passed
Test: tracefs_local events API ...passed
Test: tracefs_instances_walk API ...passed
Test: tracefs_get_clock API ...passed
Test: tracing on / off ...passed
Test: tracing options ...passed
Test: custom system directory ...passed
Test: ftrace marker ...passed
Test: kprobes ...passed
Test: synthetic events ...passed
Test: eprobes ...passed
Test: uprobes ...FAILED
1. tracefs-utest.c:2222 - ret == 0
2. tracefs-utest.c:2222 - ret == 0
Run Summary: Type Total Ran Passed Failed Inactive
suites 1 1 n/a 0 0
tests 36 36 33 3 0
asserts 30341119 30341119 30341114 5 n/a
Elapsed time = 124.937 seconds
With that,
Reviewed-by: Metin Kaya <metin.kaya@xxxxxxx>
Thanks a lot for fixing it promptly!
[1] https://lore.kernel.org/all/20241015140840.4183007-1-metin.kaya@xxxxxxx/
|