From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- tools/perf/util/parse-events.y | 647 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 647 insertions(+) create mode 100644 tools/perf/util/parse-events.y (limited to 'tools/perf/util/parse-events.y') diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y new file mode 100644 index 000000000..b531b1f0c --- /dev/null +++ b/tools/perf/util/parse-events.y @@ -0,0 +1,647 @@ +%define api.pure full +%parse-param {void *_parse_state} +%parse-param {void *scanner} +%lex-param {void* scanner} +%locations + +%{ + +#ifndef NDEBUG +#define YYDEBUG 1 +#endif + +#include +#include +#include +#include "pmu.h" +#include "pmus.h" +#include "evsel.h" +#include "parse-events.h" +#include "parse-events-bison.h" + +int parse_events_lex(YYSTYPE * yylval_param, YYLTYPE * yylloc_param , void *yyscanner); +void parse_events_error(YYLTYPE *loc, void *parse_state, void *scanner, char const *msg); + +#define PE_ABORT(val) \ +do { \ + if (val == -ENOMEM) \ + YYNOMEM; \ + YYABORT; \ +} while (0) + +static struct list_head* alloc_list(void) +{ + struct list_head *list; + + list = malloc(sizeof(*list)); + if (!list) + return NULL; + + INIT_LIST_HEAD(list); + return list; +} + +static void free_list_evsel(struct list_head* list_evsel) +{ + struct evsel *evsel, *tmp; + + list_for_each_entry_safe(evsel, tmp, list_evsel, core.node) { + list_del_init(&evsel->core.node); + evsel__put(evsel); + } + free(list_evsel); +} + +%} + +%token PE_START_EVENTS PE_START_TERMS +%token PE_VALUE PE_TERM +%token PE_EVENT_NAME +%token PE_RAW PE_NAME +%token PE_MODIFIER_EVENT PE_MODIFIER_BP PE_BP_COLON PE_BP_SLASH +%token PE_PREFIX_MEM +%token PE_ERROR +%token PE_DRV_CFG_TERM +%type PE_VALUE +%type PE_MODIFIER_EVENT +%type PE_TERM +%type PE_RAW +%type PE_NAME +%type PE_MODIFIER_BP +%type PE_EVENT_NAME +%type PE_DRV_CFG_TERM +%type name_or_raw +%destructor { free ($$); } +%type event_term +%destructor { parse_events_term__delete ($$); } +%type event_config +%type opt_event_config +%type opt_pmu_config +%destructor { parse_events_terms__delete ($$); } +%type event_pmu +%type event_legacy_mem +%type event_legacy_tracepoint +%type event_legacy_numeric +%type event_legacy_raw +%type event_def +%type event_mod +%type event_name +%type event +%type events +%type group_def +%type group +%type groups +%destructor { free_list_evsel ($$); } +%type tracepoint_name +%destructor { free ($$.sys); free ($$.event); } + +%union +{ + char *str; + u64 num; + struct parse_events_modifier mod; + enum parse_events__term_type term_type; + struct list_head *list_evsel; + struct parse_events_terms *list_terms; + struct parse_events_term *term; + struct tracepoint_name { + char *sys; + char *event; + } tracepoint_name; +} +%% + + /* + * Entry points. We are either parsing events or terminals. Just terminal + * parsing is used for parsing events in sysfs. + */ +start: +PE_START_EVENTS start_events +| +PE_START_TERMS start_terms + +start_events: groups +{ + /* Take the parsed events, groups.. and place into parse_state. */ + struct list_head *groups = $1; + struct parse_events_state *parse_state = _parse_state; + + list_splice_tail(groups, &parse_state->list); + free(groups); +} + +groups: /* A list of groups or events. */ +groups ',' group +{ + /* Merge group into the list of events/groups. */ + struct list_head *groups = $1; + struct list_head *group = $3; + + list_splice_tail(group, groups); + free(group); + $$ = groups; +} +| +groups ',' event +{ + /* Merge event into the list of events/groups. */ + struct list_head *groups = $1; + struct list_head *event = $3; + + + list_splice_tail(event, groups); + free(event); + $$ = groups; +} +| +group +| +event + +group: +group_def ':' PE_MODIFIER_EVENT +{ + /* Apply the modifier to the events in the group_def. */ + struct list_head *list = $1; + int err; + + err = parse_events__modifier_group(_parse_state, &@3, list, $3); + if (err) + YYABORT; + $$ = list; +} +| +group_def + +group_def: +PE_NAME '{' events '}' +{ + struct list_head *list = $3; + + /* + * Set the first entry of list to be the leader. Set the group name on + * the leader to $1 taking ownership. + */ + parse_events__set_leader($1, list); + $$ = list; +} +| +'{' events '}' +{ + struct list_head *list = $2; + + /* Set the first entry of list to be the leader clearing the group name. */ + parse_events__set_leader(NULL, list); + $$ = list; +} + +events: +events ',' event +{ + struct list_head *events = $1; + struct list_head *event = $3; + + list_splice_tail(event, events); + free(event); + $$ = events; +} +| +event + +event: event_mod + +event_mod: +event_name PE_MODIFIER_EVENT +{ + struct list_head *list = $1; + int err; + + /* + * Apply modifier on all events added by single event definition + * (there could be more events added for multiple tracepoint + * definitions via '*?'. + */ + err = parse_events__modifier_event(_parse_state, &@2, list, $2); + if (err) + YYABORT; + $$ = list; +} +| +event_name + +event_name: +PE_EVENT_NAME event_def +{ + /* + * When an event is parsed the text is rewound and the entire text of + * the event is set to the str of PE_EVENT_NAME token matched here. If + * no name was on an event via a term, set the name to the entire text + * taking ownership of the allocation. + */ + int err = parse_events__set_default_name($2, $1); + + if (err) { + free_list_evsel($2); + YYNOMEM; + } + $$ = $2; +} +| +event_def + +event_def: event_pmu | + event_legacy_mem sep_dc | + event_legacy_tracepoint sep_dc | + event_legacy_numeric sep_dc | + event_legacy_raw sep_dc + +event_pmu: +PE_NAME opt_pmu_config +{ + /* List of created evsels. */ + struct list_head *list = NULL; + int err = parse_events_multi_pmu_add_or_add_pmu(_parse_state, $1, $2, &list, &@1); + + parse_events_terms__delete($2); + free($1); + if (err) + PE_ABORT(err); + $$ = list; +} +| +PE_NAME sep_dc +{ + struct list_head *list; + int err; + + err = parse_events_multi_pmu_add(_parse_state, $1, /*const_parsed_terms*/NULL, &list, &@1); + if (err < 0) { + struct parse_events_state *parse_state = _parse_state; + struct parse_events_error *error = parse_state->error; + char *help; + + if (asprintf(&help, "Unable to find event on a PMU of '%s'", $1) < 0) + help = NULL; + parse_events_error__handle(error, @1.first_column, strdup("Bad event name"), help); + free($1); + PE_ABORT(err); + } + free($1); + $$ = list; +} + +event_legacy_mem: +PE_PREFIX_MEM PE_VALUE PE_BP_SLASH PE_VALUE PE_BP_COLON PE_MODIFIER_BP opt_event_config +{ + struct list_head *list; + int err; + + list = alloc_list(); + if (!list) + YYNOMEM; + + err = parse_events_add_breakpoint(_parse_state, list, + $2, $6, $4, $7); + parse_events_terms__delete($7); + free($6); + if (err) { + free(list); + PE_ABORT(err); + } + $$ = list; +} +| +PE_PREFIX_MEM PE_VALUE PE_BP_SLASH PE_VALUE opt_event_config +{ + struct list_head *list; + int err; + + list = alloc_list(); + if (!list) + YYNOMEM; + + err = parse_events_add_breakpoint(_parse_state, list, + $2, NULL, $4, $5); + parse_events_terms__delete($5); + if (err) { + free(list); + PE_ABORT(err); + } + $$ = list; +} +| +PE_PREFIX_MEM PE_VALUE PE_BP_COLON PE_MODIFIER_BP opt_event_config +{ + struct list_head *list; + int err; + + list = alloc_list(); + if (!list) + YYNOMEM; + + err = parse_events_add_breakpoint(_parse_state, list, + $2, $4, 0, $5); + parse_events_terms__delete($5); + free($4); + if (err) { + free(list); + PE_ABORT(err); + } + $$ = list; +} +| +PE_PREFIX_MEM PE_VALUE opt_event_config +{ + struct list_head *list; + int err; + + list = alloc_list(); + if (!list) + YYNOMEM; + err = parse_events_add_breakpoint(_parse_state, list, + $2, NULL, 0, $3); + parse_events_terms__delete($3); + if (err) { + free(list); + PE_ABORT(err); + } + $$ = list; +} + +event_legacy_tracepoint: +tracepoint_name opt_event_config +{ + struct parse_events_state *parse_state = _parse_state; + struct parse_events_error *error = parse_state->error; + struct list_head *list; + int err; + + list = alloc_list(); + if (!list) + YYNOMEM; + + err = parse_events_add_tracepoint(parse_state, list, $1.sys, $1.event, + error, $2, &@1); + + parse_events_terms__delete($2); + free($1.sys); + free($1.event); + if (err) { + free(list); + PE_ABORT(err); + } + $$ = list; +} + +tracepoint_name: +PE_NAME ':' PE_NAME +{ + struct tracepoint_name tracepoint = {$1, $3}; + + $$ = tracepoint; +} + +event_legacy_numeric: +PE_VALUE ':' PE_VALUE opt_event_config +{ + struct list_head *list; + int err; + + list = alloc_list(); + if (!list) + YYNOMEM; + err = parse_events_add_numeric(_parse_state, list, (u32)$1, $3, $4, + /*wildcard=*/false); + parse_events_terms__delete($4); + if (err) { + free(list); + PE_ABORT(err); + } + $$ = list; +} + +event_legacy_raw: +PE_RAW opt_event_config +{ + struct list_head *list; + int err; + u64 num; + + list = alloc_list(); + if (!list) + YYNOMEM; + errno = 0; + num = strtoull($1 + 1, NULL, 16); + /* Given the lexer will only give [a-fA-F0-9]+ a failure here should be impossible. */ + if (errno) + YYABORT; + free($1); + err = parse_events_add_numeric(_parse_state, list, PERF_TYPE_RAW, num, $2, + /*wildcard=*/false); + parse_events_terms__delete($2); + if (err) { + free(list); + PE_ABORT(err); + } + $$ = list; +} + +opt_event_config: +'/' event_config '/' +{ + $$ = $2; +} +| +'/' '/' +{ + $$ = NULL; +} +| +{ + $$ = NULL; +} + +opt_pmu_config: +'/' event_config '/' +{ + $$ = $2; +} +| +'/' '/' +{ + $$ = NULL; +} + +start_terms: event_config +{ + struct parse_events_state *parse_state = _parse_state; + if (parse_state->terms) { + parse_events_terms__delete ($1); + YYABORT; + } + parse_state->terms = $1; +} + +event_config: +event_config ',' event_term +{ + struct parse_events_terms *head = $1; + struct parse_events_term *term = $3; + + if (!head) { + parse_events_term__delete(term); + YYABORT; + } + list_add_tail(&term->list, &head->terms); + $$ = $1; +} +| +event_term +{ + struct parse_events_terms *head = malloc(sizeof(*head)); + struct parse_events_term *term = $1; + + if (!head) + YYNOMEM; + parse_events_terms__init(head); + list_add_tail(&term->list, &head->terms); + $$ = head; +} + +name_or_raw: PE_RAW | PE_NAME + +event_term: +PE_RAW +{ + struct parse_events_term *term; + int err = parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_RAW, + strdup("raw"), $1, &@1, &@1); + + if (err) { + free($1); + PE_ABORT(err); + } + $$ = term; +} +| +name_or_raw '=' name_or_raw +{ + struct parse_events_term *term; + int err = parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_USER, $1, $3, &@1, &@3); + + if (err) { + free($1); + free($3); + PE_ABORT(err); + } + $$ = term; +} +| +name_or_raw '=' PE_VALUE +{ + struct parse_events_term *term; + int err = parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_USER, + $1, $3, /*novalue=*/false, &@1, &@3); + + if (err) { + free($1); + PE_ABORT(err); + } + $$ = term; +} +| +PE_NAME +{ + struct parse_events_term *term; + int err = parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_USER, + $1, /*num=*/1, /*novalue=*/true, &@1, /*loc_val=*/NULL); + + if (err) { + free($1); + PE_ABORT(err); + } + $$ = term; +} +| +PE_TERM '=' name_or_raw +{ + struct parse_events_term *term; + int err = parse_events_term__str(&term, $1, /*config=*/NULL, $3, &@1, &@3); + + if (err) { + free($3); + PE_ABORT(err); + } + $$ = term; +} +| +PE_TERM '=' PE_TERM +{ + struct parse_events_term *term; + int err = parse_events_term__term(&term, $1, $3, &@1, &@3); + + if (err) + PE_ABORT(err); + + $$ = term; +} +| +PE_TERM '=' PE_VALUE +{ + struct parse_events_term *term; + int err = parse_events_term__num(&term, $1, + /*config=*/NULL, $3, /*novalue=*/false, + &@1, &@3); + + if (err) + PE_ABORT(err); + + $$ = term; +} +| +PE_TERM +{ + struct parse_events_term *term; + int err = parse_events_term__num(&term, $1, + /*config=*/NULL, /*num=*/1, /*novalue=*/true, + &@1, /*loc_val=*/NULL); + + if (err) + PE_ABORT(err); + + $$ = term; +} +| +PE_DRV_CFG_TERM +{ + struct parse_events_term *term; + char *config = strdup($1); + int err; + + if (!config) + YYNOMEM; + err = parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_DRV_CFG, config, $1, &@1, NULL); + if (err) { + free($1); + free(config); + PE_ABORT(err); + } + $$ = term; +} + +sep_dc: ':' | + +%% + +void parse_events_error(YYLTYPE *loc, void *_parse_state, + void *scanner __maybe_unused, + char const *msg __maybe_unused) +{ + struct parse_events_state *parse_state = _parse_state; + + if (!parse_state->error || !list_empty(&parse_state->error->list)) + return; + + parse_events_error__handle(parse_state->error, loc->last_column, + strdup("Unrecognized input"), NULL); +} -- cgit v1.3.1