diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 6383115e9d2c..2e028854bac7 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -307,7 +307,7 @@ DECLARE_PER_CPU(int, disable_stack_tracer); static inline void stack_tracer_disable(void) { /* Preemption or interupts must be disabled */ - if (IS_ENABLED(CONFIG_PREEMPT_DEBUG)) + if (IS_ENABLED(CONFIG_DEBUG_PREEMPT)) WARN_ON_ONCE(!preempt_count() || !irqs_disabled()); this_cpu_inc(disable_stack_tracer); } @@ -320,7 +320,7 @@ static inline void stack_tracer_disable(void) */ static inline void stack_tracer_enable(void) { - if (IS_ENABLED(CONFIG_PREEMPT_DEBUG)) + if (IS_ENABLED(CONFIG_DEBUG_PREEMPT)) WARN_ON_ONCE(!preempt_count() || !irqs_disabled()); this_cpu_dec(disable_stack_tracer); } diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 5012b524283d..7f11050746ae 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -217,7 +217,6 @@ enum { TRACE_EVENT_FL_CAP_ANY_BIT, TRACE_EVENT_FL_NO_SET_FILTER_BIT, TRACE_EVENT_FL_IGNORE_ENABLE_BIT, - TRACE_EVENT_FL_WAS_ENABLED_BIT, TRACE_EVENT_FL_TRACEPOINT_BIT, TRACE_EVENT_FL_KPROBE_BIT, TRACE_EVENT_FL_UPROBE_BIT, @@ -229,9 +228,6 @@ enum { * CAP_ANY - Any user can enable for perf * NO_SET_FILTER - Set when filter has error and is to be ignored * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file - * WAS_ENABLED - Set and stays set when an event was ever enabled - * (used for module unloading, if a module event is enabled, - * it is best to clear the buffers that used it). * TRACEPOINT - Event is a tracepoint * KPROBE - Event is a kprobe * UPROBE - Event is a uprobe @@ -241,7 +237,6 @@ enum { TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT), TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT), TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), - TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT), TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), @@ -306,6 +301,7 @@ enum { EVENT_FILE_FL_TRIGGER_MODE_BIT, EVENT_FILE_FL_TRIGGER_COND_BIT, EVENT_FILE_FL_PID_FILTER_BIT, + EVENT_FILE_FL_WAS_ENABLED_BIT, }; /* @@ -321,6 +317,7 @@ enum { * TRIGGER_MODE - When set, invoke the triggers associated with the event * TRIGGER_COND - When set, one or more triggers has an associated filter * PID_FILTER - When set, the event is filtered based on pid + * WAS_ENABLED - Set when enabled to know to clear trace on module removal */ enum { EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT), @@ -333,6 +330,7 @@ enum { EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT), EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT), EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT), + EVENT_FILE_FL_WAS_ENABLED = (1 << EVENT_FILE_FL_WAS_ENABLED_BIT), }; struct trace_event_file { diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 96cea88fa00f..6abfafd7f173 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2828,13 +2828,14 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command) if (!command || !ftrace_enabled) { /* - * If these are per_cpu ops, they still need their - * per_cpu field freed. Since, function tracing is + * If these are dynamic or per_cpu ops, they still + * need their data freed. Since, function tracing is * not currently active, we can just free them * without synchronizing all CPUs. */ - if (ops->flags & FTRACE_OPS_FL_PER_CPU) - per_cpu_ops_free(ops); + if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU)) + goto free_ops; + return 0; } @@ -2900,6 +2901,7 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command) if (IS_ENABLED(CONFIG_PREEMPT)) synchronize_rcu_tasks(); + free_ops: arch_ftrace_trampoline_free(ops); if (ops->flags & FTRACE_OPS_FL_PER_CPU) @@ -5690,10 +5692,51 @@ static int referenced_filters(struct dyn_ftrace *rec) return cnt; } +static void +clear_mod_from_hash(struct ftrace_page *pg, struct ftrace_hash *hash) +{ + struct ftrace_func_entry *entry; + struct dyn_ftrace *rec; + int i; + + if (ftrace_hash_empty(hash)) + return; + + for (i = 0; i < pg->index; i++) { + rec = &pg->records[i]; + entry = __ftrace_lookup_ip(hash, rec->ip); + /* + * Do not allow this rec to match again. + * Yeah, it may waste some memory, but will be removed + * if/when the hash is modified again. + */ + if (entry) + entry->ip = 0; + } +} + +/* Clear any records from hashs */ +static void clear_mod_from_hashes(struct ftrace_page *pg) +{ + struct trace_array *tr; + + mutex_lock(&trace_types_lock); + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (!tr->ops || !tr->ops->func_hash) + continue; + mutex_lock(&tr->ops->func_hash->regex_lock); + clear_mod_from_hash(pg, tr->ops->func_hash->filter_hash); + clear_mod_from_hash(pg, tr->ops->func_hash->notrace_hash); + mutex_unlock(&tr->ops->func_hash->regex_lock); + } + mutex_unlock(&trace_types_lock); +} + void ftrace_release_mod(struct module *mod) { struct dyn_ftrace *rec; struct ftrace_page **last_pg; + struct ftrace_page *tmp_page = NULL; struct ftrace_page *pg; int order; @@ -5723,14 +5766,25 @@ void ftrace_release_mod(struct module *mod) ftrace_update_tot_cnt -= pg->index; *last_pg = pg->next; - order = get_count_order(pg->size / ENTRIES_PER_PAGE); - free_pages((unsigned long)pg->records, order); - kfree(pg); + + pg->next = tmp_page; + tmp_page = pg; } else last_pg = &pg->next; } out_unlock: mutex_unlock(&ftrace_lock); + + for (pg = tmp_page; pg; pg = tmp_page) { + + /* Needs to be called outside of ftrace_lock */ + clear_mod_from_hashes(pg); + + order = get_count_order(pg->size / ENTRIES_PER_PAGE); + free_pages((unsigned long)pg->records, order); + tmp_page = pg->next; + kfree(pg); + } } void ftrace_module_enable(struct module *mod) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 44004d8aa3b3..5360b7aec57a 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1702,6 +1702,9 @@ void tracing_reset_all_online_cpus(void) struct trace_array *tr; list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (!tr->clear_trace) + continue; + tr->clear_trace = false; tracing_reset_online_cpus(&tr->trace_buffer); #ifdef CONFIG_TRACER_MAX_TRACE tracing_reset_online_cpus(&tr->max_buffer); @@ -2799,11 +2802,17 @@ static char *get_trace_buf(void) if (!buffer || buffer->nesting >= 4) return NULL; - return &buffer->buffer[buffer->nesting++][0]; + buffer->nesting++; + + /* Interrupts must see nesting incremented before we use the buffer */ + barrier(); + return &buffer->buffer[buffer->nesting][0]; } static void put_trace_buf(void) { + /* Don't let the decrement of nesting leak before this */ + barrier(); this_cpu_dec(trace_percpu_buffer->nesting); } @@ -6220,7 +6229,7 @@ static int tracing_set_clock(struct trace_array *tr, const char *clockstr) tracing_reset_online_cpus(&tr->trace_buffer); #ifdef CONFIG_TRACER_MAX_TRACE - if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) + if (tr->max_buffer.buffer) ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); tracing_reset_online_cpus(&tr->max_buffer); #endif diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 490ba229931d..fb5d54d0d1b3 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -245,6 +245,7 @@ struct trace_array { int stop_count; int clock_id; int nr_topts; + bool clear_trace; struct tracer *current_trace; unsigned int trace_flags; unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 36132f9280e6..87468398b9ed 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -406,7 +406,7 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file, if (file->flags & EVENT_FILE_FL_RECORDED_TGID) { tracing_stop_tgid_record(); - clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); + clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); } call->class->reg(call, TRACE_REG_UNREGISTER, file); @@ -466,7 +466,7 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file, set_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags); /* WAS_ENABLED gets set but never cleared. */ - call->flags |= TRACE_EVENT_FL_WAS_ENABLED; + set_bit(EVENT_FILE_FL_WAS_ENABLED_BIT, &file->flags); } break; } @@ -2058,6 +2058,10 @@ static void event_remove(struct trace_event_call *call) do_for_each_event_file(tr, file) { if (file->event_call != call) continue; + + if (file->flags & EVENT_FILE_FL_WAS_ENABLED) + tr->clear_trace = true; + ftrace_event_enable_disable(file, 0); /* * The do_for_each_event_file() is @@ -2396,15 +2400,11 @@ static void trace_module_add_events(struct module *mod) static void trace_module_remove_events(struct module *mod) { struct trace_event_call *call, *p; - bool clear_trace = false; down_write(&trace_event_sem); list_for_each_entry_safe(call, p, &ftrace_events, list) { - if (call->mod == mod) { - if (call->flags & TRACE_EVENT_FL_WAS_ENABLED) - clear_trace = true; + if (call->mod == mod) __trace_remove_event_call(call); - } } up_write(&trace_event_sem); @@ -2416,8 +2416,7 @@ static void trace_module_remove_events(struct module *mod) * over from this module may be passed to the new module events and * unexpected results may occur. */ - if (clear_trace) - tracing_reset_all_online_cpus(); + tracing_reset_all_online_cpus(); } static int trace_module_notify(struct notifier_block *self, diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index cb917cebae29..b17ec642793b 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -273,7 +273,7 @@ static int trace_selftest_ops(struct trace_array *tr, int cnt) goto out_free; if (cnt > 1) { if (trace_selftest_test_global_cnt == 0) - goto out; + goto out_free; } if (trace_selftest_test_dyn_cnt == 0) goto out_free;