#ifndef __PERF_PARSE_EVENTS_H #define __PERF_PARSE_EVENTS_H /* * Parse symbolic events/counts passed in as options: */ #include #include #include #include struct list_head; struct perf_evsel; struct perf_evlist; struct parse_events_error; struct option; struct tracepoint_path { char *system; char *name; struct tracepoint_path *next; }; struct tracepoint_path *tracepoint_id_to_path(u64 config); struct tracepoint_path *tracepoint_name_to_path(const char *name); bool have_tracepoints(struct list_head *evlist); const char *event_type(int type); int parse_events_option(const struct option *opt, const char *str, int unset); int parse_events(struct perf_evlist *evlist, const char *str, struct parse_events_error *error); int parse_events_terms(struct list_head *terms, const char *str); int parse_filter(const struct option *opt, const char *str, int unset); int exclude_perf(const struct option *opt, const char *arg, int unset); #define EVENTS_HELP_MAX (128*1024) enum perf_pmu_event_symbol_type { PMU_EVENT_SYMBOL_ERR, /* not a PMU EVENT */ PMU_EVENT_SYMBOL, /* normal style PMU event */ PMU_EVENT_SYMBOL_PREFIX, /* prefix of pre-suf style event */ PMU_EVENT_SYMBOL_SUFFIX, /* suffix of pre-suf style event */ }; struct perf_pmu_event_symbol { char *symbol; enum perf_pmu_event_symbol_type type; }; enum { PARSE_EVENTS__TERM_TYPE_NUM, PARSE_EVENTS__TERM_TYPE_STR, }; enum { PARSE_EVENTS__TERM_TYPE_USER, PARSE_EVENTS__TERM_TYPE_CONFIG, PARSE_EVENTS__TERM_TYPE_CONFIG1, PARSE_EVENTS__TERM_TYPE_CONFIG2, PARSE_EVENTS__TERM_TYPE_NAME, PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD, PARSE_EVENTS__TERM_TYPE_SAMPLE_FREQ, PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE, PARSE_EVENTS__TERM_TYPE_TIME, PARSE_EVENTS__TERM_TYPE_CALLGRAPH, PARSE_EVENTS__TERM_TYPE_STACKSIZE, PARSE_EVENTS__TERM_TYPE_NOINHERIT, PARSE_EVENTS__TERM_TYPE_INHERIT, PARSE_EVENTS__TERM_TYPE_MAX_STACK, PARSE_EVENTS__TERM_TYPE_NOOVERWRITE, PARSE_EVENTS__TERM_TYPE_OVERWRITE, PARSE_EVENTS__TERM_TYPE_DRV_CFG, __PARSE_EVENTS__TERM_TYPE_NR, }; struct parse_events_array { size_t nr_ranges; struct { unsigned int start; size_t length; } *ranges; }; struct parse_events_term { char *config; struct parse_events_array array; union { char *str; u64 num; } val; int type_val; int type_term; struct list_head list; bool used; /* error string indexes for within parsed string */ int err_term; int err_val; }; struct parse_events_error { int idx; /* index in the parsed string */ char *str; /* string to display at the index */ char *help; /* optional help string */ }; struct parse_events_evlist { struct list_head list; int idx; int nr_groups; struct parse_events_error *error; struct perf_evlist *evlist; }; struct parse_events_terms { struct list_head *terms; }; void parse_events__shrink_config_terms(void); int parse_events__is_hardcoded_term(struct parse_events_term *term); int parse_events_term__num(struct parse_events_term **term, int type_term, char *config, u64 num, void *loc_term, void *loc_val); int parse_events_term__str(struct parse_events_term **term, int type_term, char *config, char *str, void *loc_term, void *loc_val); int parse_events_term__sym_hw(struct parse_events_term **term, char *config, unsigned idx); int parse_events_term__clone(struct parse_events_term **new, struct parse_events_term *term); void parse_events_terms__delete(struct list_head *terms); void parse_events_terms__purge(struct list_head *terms); void parse_events__clear_array(struct parse_events_array *a); int parse_events__modifier_event(struct list_head *list, char *str, bool add); int parse_events__modifier_group(struct list_head *list, char *event_mod); int parse_events_name(struct list_head *list, char *name); int parse_events_add_tracepoint(struct list_head *list, int *idx, const char *sys, const char *event, struct parse_events_error *error, struct list_head *head_config); int parse_events_load_bpf(struct parse_events_evlist *data, struct list_head *list, char *bpf_file_name, bool source, struct list_head *head_config); /* Provide this function for perf test */ struct bpf_object; int parse_events_load_bpf_obj(struct parse_events_evlist *data, struct list_head *list, struct bpf_object *obj, struct list_head *head_config); int parse_events_add_numeric(struct parse_events_evlist *data, struct list_head *list, u32 type, u64 config, struct list_head *head_config); int parse_events_add_cache(struct list_head *list, int *idx, char *type, char *op_result1, char *op_result2, struct parse_events_error *error, struct list_head *head_config); int parse_events_add_breakpoint(struct list_head *list, int *idx, void *ptr, char *type, u64 len); int parse_events_add_pmu(struct parse_events_evlist *data, struct list_head *list, char *name, struct list_head *head_config); enum perf_pmu_event_symbol_type perf_pmu__parse_check(const char *name); void parse_events__set_leader(char *name, struct list_head *list); void parse_events_update_lists(struct list_head *list_event, struct list_head *list_all); void parse_events_evlist_error(struct parse_events_evlist *data, int idx, const char *str); void print_events(const char *event_glob, bool name_only, bool quiet, bool long_desc); struct event_symbol { const char *symbol; const char *alias; }; extern struct event_symbol event_symbols_hw[]; extern struct event_symbol event_symbols_sw[]; void print_symbol_events(const char *event_glob, unsigned type, struct event_symbol *syms, unsigned max, bool name_only); void print_tracepoint_events(const char *subsys_glob, const char *event_glob, bool name_only); int print_hwcache_events(const char *event_glob, bool name_only); void print_sdt_events(const char *subsys_glob, const char *event_glob, bool name_only); int is_valid_tracepoint(const char *event_string); int valid_event_mount(const char *eventfs); char *parse_events_formats_error_string(char *additional_terms); #endif /* __PERF_PARSE_EVENTS_H */ ss='commit-msg'>percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'include/crypto')