From 29ad23b00474c34e3b5040dda508c78d33a1a3eb Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 14 Oct 2013 17:24:26 +0900 Subject: ftrace: Add set_graph_notrace filter The set_graph_notrace filter is analogous to set_ftrace_notrace and can be used for eliminating uninteresting part of function graph trace output. It also works with set_graph_function nicely. # cd /sys/kernel/debug/tracing/ # echo do_page_fault > set_graph_function # perf ftrace live true 2) | do_page_fault() { 2) | __do_page_fault() { 2) 0.381 us | down_read_trylock(); 2) 0.055 us | __might_sleep(); 2) 0.696 us | find_vma(); 2) | handle_mm_fault() { 2) | handle_pte_fault() { 2) | __do_fault() { 2) | filemap_fault() { 2) | find_get_page() { 2) 0.033 us | __rcu_read_lock(); 2) 0.035 us | __rcu_read_unlock(); 2) 1.696 us | } 2) 0.031 us | __might_sleep(); 2) 2.831 us | } 2) | _raw_spin_lock() { 2) 0.046 us | add_preempt_count(); 2) 0.841 us | } 2) 0.033 us | page_add_file_rmap(); 2) | _raw_spin_unlock() { 2) 0.057 us | sub_preempt_count(); 2) 0.568 us | } 2) | unlock_page() { 2) 0.084 us | page_waitqueue(); 2) 0.126 us | __wake_up_bit(); 2) 1.117 us | } 2) 7.729 us | } 2) 8.397 us | } 2) 8.956 us | } 2) 0.085 us | up_read(); 2) + 12.745 us | } 2) + 13.401 us | } ... # echo handle_mm_fault > set_graph_notrace # perf ftrace live true 1) | do_page_fault() { 1) | __do_page_fault() { 1) 0.205 us | down_read_trylock(); 1) 0.041 us | __might_sleep(); 1) 0.344 us | find_vma(); 1) 0.069 us | up_read(); 1) 4.692 us | } 1) 5.311 us | } ... Link: http://lkml.kernel.org/r/1381739066-7531-5-git-send-email-namhyung@kernel.org Signed-off-by: Namhyung Kim Signed-off-by: Steven Rostedt --- include/linux/ftrace.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 9f15c0064c50..ec85d48619e1 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -721,6 +721,7 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, extern char __irqentry_text_start[]; extern char __irqentry_text_end[]; +#define FTRACE_NOTRACE_DEPTH 65536 #define FTRACE_RETFUNC_DEPTH 50 #define FTRACE_RETSTACK_ALLOC_SIZE 32 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc, -- cgit v1.2.3 From f306cc82a93d6b19f01634b80c580b9755c8b7cc Mon Sep 17 00:00:00 2001 From: Tom Zanussi Date: Thu, 24 Oct 2013 08:34:17 -0500 Subject: tracing: Update event filters for multibuffer The trace event filters are still tied to event calls rather than event files, which means you don't get what you'd expect when using filters in the multibuffer case: Before: # echo 'bytes_alloc > 8192' > /sys/kernel/debug/tracing/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 8192 # mkdir /sys/kernel/debug/tracing/instances/test1 # echo 'bytes_alloc > 2048' > /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 2048 # cat /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter bytes_alloc > 2048 Setting the filter in tracing/instances/test1/events shouldn't affect the same event in tracing/events as it does above. After: # echo 'bytes_alloc > 8192' > /sys/kernel/debug/tracing/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 8192 # mkdir /sys/kernel/debug/tracing/instances/test1 # echo 'bytes_alloc > 2048' > /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 8192 # cat /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter bytes_alloc > 2048 We'd like to just move the filter directly from ftrace_event_call to ftrace_event_file, but there are a couple cases that don't yet have multibuffer support and therefore have to continue using the current event_call-based filters. For those cases, a new USE_CALL_FILTER bit is added to the event_call flags, whose main purpose is to keep the old behavior for those cases until they can be updated with multibuffer support; at that point, the USE_CALL_FILTER flag (and the new associated call_filter_check_discard() function) can go away. The multibuffer support also made filter_current_check_discard() redundant, so this change removes that function as well and replaces it with filter_check_discard() (or call_filter_check_discard() as appropriate). Link: http://lkml.kernel.org/r/f16e9ce4270c62f46b2e966119225e1c3cca7e60.1382620672.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt --- include/linux/ftrace_event.h | 25 +++- include/linux/syscalls.h | 4 +- include/trace/ftrace.h | 7 +- kernel/trace/trace.c | 40 +++++-- kernel/trace/trace.h | 18 +-- kernel/trace/trace_branch.c | 2 +- kernel/trace/trace_events.c | 23 ++-- kernel/trace/trace_events_filter.c | 218 ++++++++++++++++++++++++++++------- kernel/trace/trace_export.c | 2 +- kernel/trace/trace_functions_graph.c | 4 +- kernel/trace/trace_kprobe.c | 4 +- kernel/trace/trace_mmiotrace.c | 4 +- kernel/trace/trace_sched_switch.c | 4 +- kernel/trace/trace_syscalls.c | 8 +- kernel/trace/trace_uprobe.c | 3 +- 15 files changed, 264 insertions(+), 102 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 5eaa746735ff..9abbe630c456 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -202,6 +202,7 @@ enum { TRACE_EVENT_FL_NO_SET_FILTER_BIT, TRACE_EVENT_FL_IGNORE_ENABLE_BIT, TRACE_EVENT_FL_WAS_ENABLED_BIT, + TRACE_EVENT_FL_USE_CALL_FILTER_BIT, }; /* @@ -213,6 +214,7 @@ enum { * 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). + * USE_CALL_FILTER - For ftrace internal events, don't use file filter */ enum { TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT), @@ -220,6 +222,7 @@ enum { 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_USE_CALL_FILTER = (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT), }; struct ftrace_event_call { @@ -238,6 +241,7 @@ struct ftrace_event_call { * bit 2: failed to apply filter * bit 3: ftrace internal event (do not enable) * bit 4: Event was enabled by module + * bit 5: use call filter rather than file filter */ int flags; /* static flags of different events */ @@ -253,6 +257,8 @@ struct ftrace_subsystem_dir; enum { FTRACE_EVENT_FL_ENABLED_BIT, FTRACE_EVENT_FL_RECORDED_CMD_BIT, + FTRACE_EVENT_FL_FILTERED_BIT, + FTRACE_EVENT_FL_NO_SET_FILTER_BIT, FTRACE_EVENT_FL_SOFT_MODE_BIT, FTRACE_EVENT_FL_SOFT_DISABLED_BIT, }; @@ -261,6 +267,8 @@ enum { * Ftrace event file flags: * ENABLED - The event is enabled * RECORDED_CMD - The comms should be recorded at sched_switch + * FILTERED - The event has a filter attached + * NO_SET_FILTER - Set when filter has error and is to be ignored * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED * SOFT_DISABLED - When set, do not trace the event (even though its * tracepoint may be enabled) @@ -268,6 +276,8 @@ enum { enum { FTRACE_EVENT_FL_ENABLED = (1 << FTRACE_EVENT_FL_ENABLED_BIT), FTRACE_EVENT_FL_RECORDED_CMD = (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT), + FTRACE_EVENT_FL_FILTERED = (1 << FTRACE_EVENT_FL_FILTERED_BIT), + FTRACE_EVENT_FL_NO_SET_FILTER = (1 << FTRACE_EVENT_FL_NO_SET_FILTER_BIT), FTRACE_EVENT_FL_SOFT_MODE = (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT), FTRACE_EVENT_FL_SOFT_DISABLED = (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT), }; @@ -275,6 +285,7 @@ enum { struct ftrace_event_file { struct list_head list; struct ftrace_event_call *event_call; + struct event_filter *filter; struct dentry *dir; struct trace_array *tr; struct ftrace_subsystem_dir *system; @@ -310,12 +321,16 @@ struct ftrace_event_file { #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */ -extern void destroy_preds(struct ftrace_event_call *call); +extern void destroy_preds(struct ftrace_event_file *file); +extern void destroy_call_preds(struct ftrace_event_call *call); extern int filter_match_preds(struct event_filter *filter, void *rec); -extern int filter_current_check_discard(struct ring_buffer *buffer, - struct ftrace_event_call *call, - void *rec, - struct ring_buffer_event *event); + +extern int filter_check_discard(struct ftrace_event_file *file, void *rec, + struct ring_buffer *buffer, + struct ring_buffer_event *event); +extern int call_filter_check_discard(struct ftrace_event_call *call, void *rec, + struct ring_buffer *buffer, + struct ring_buffer_event *event); enum { FILTER_OTHER = 0, diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 7fac04e7ff6e..10bafa97049d 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -120,7 +120,7 @@ extern struct trace_event_functions exit_syscall_print_funcs; .class = &event_class_syscall_enter, \ .event.funcs = &enter_syscall_print_funcs, \ .data = (void *)&__syscall_meta_##sname,\ - .flags = TRACE_EVENT_FL_CAP_ANY, \ + .flags = TRACE_EVENT_FL_CAP_ANY | TRACE_EVENT_FL_USE_CALL_FILTER,\ }; \ static struct ftrace_event_call __used \ __attribute__((section("_ftrace_events"))) \ @@ -134,7 +134,7 @@ extern struct trace_event_functions exit_syscall_print_funcs; .class = &event_class_syscall_exit, \ .event.funcs = &exit_syscall_print_funcs, \ .data = (void *)&__syscall_meta_##sname,\ - .flags = TRACE_EVENT_FL_CAP_ANY, \ + .flags = TRACE_EVENT_FL_CAP_ANY | TRACE_EVENT_FL_USE_CALL_FILTER,\ }; \ static struct ftrace_event_call __used \ __attribute__((section("_ftrace_events"))) \ diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 5c7ab17cbb02..52594b20179e 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -437,9 +437,8 @@ static inline notrace int ftrace_get_offsets_##call( \ * { ; } <-- Here we assign the entries by the __field and * __array macros. * - * if (!filter_current_check_discard(buffer, event_call, entry, event)) - * trace_nowake_buffer_unlock_commit(buffer, - * event, irq_flags, pc); + * if (!filter_check_discard(ftrace_file, entry, buffer, event)) + * trace_buffer_unlock_commit(buffer, event, irq_flags, pc); * } * * static struct trace_event ftrace_event_type_ = { @@ -553,7 +552,7 @@ ftrace_raw_event_##call(void *__data, proto) \ \ { assign; } \ \ - if (!filter_current_check_discard(buffer, event_call, entry, event)) \ + if (!filter_check_discard(ftrace_file, entry, buffer, event)) \ trace_buffer_unlock_commit(buffer, event, irq_flags, pc); \ } /* diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 063a92bad578..489da8b19f30 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -235,13 +235,33 @@ void trace_array_put(struct trace_array *this_tr) mutex_unlock(&trace_types_lock); } -int filter_current_check_discard(struct ring_buffer *buffer, - struct ftrace_event_call *call, void *rec, - struct ring_buffer_event *event) +int filter_check_discard(struct ftrace_event_file *file, void *rec, + struct ring_buffer *buffer, + struct ring_buffer_event *event) { - return filter_check_discard(call, rec, buffer, event); + if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && + !filter_match_preds(file->filter, rec)) { + ring_buffer_discard_commit(buffer, event); + return 1; + } + + return 0; +} +EXPORT_SYMBOL_GPL(filter_check_discard); + +int call_filter_check_discard(struct ftrace_event_call *call, void *rec, + struct ring_buffer *buffer, + struct ring_buffer_event *event) +{ + if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && + !filter_match_preds(call->filter, rec)) { + ring_buffer_discard_commit(buffer, event); + return 1; + } + + return 0; } -EXPORT_SYMBOL_GPL(filter_current_check_discard); +EXPORT_SYMBOL_GPL(call_filter_check_discard); cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) { @@ -1633,7 +1653,7 @@ trace_function(struct trace_array *tr, entry->ip = ip; entry->parent_ip = parent_ip; - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); } @@ -1717,7 +1737,7 @@ static void __ftrace_trace_stack(struct ring_buffer *buffer, entry->size = trace.nr_entries; - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); out: @@ -1819,7 +1839,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) trace.entries = entry->caller; save_stack_trace_user(&trace); - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); out_drop_count: @@ -2011,7 +2031,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) entry->fmt = fmt; memcpy(entry->buf, tbuffer, sizeof(u32) * len); - if (!filter_check_discard(call, entry, buffer, event)) { + if (!call_filter_check_discard(call, entry, buffer, event)) { __buffer_unlock_commit(buffer, event); ftrace_trace_stack(buffer, flags, 6, pc); } @@ -2066,7 +2086,7 @@ __trace_array_vprintk(struct ring_buffer *buffer, memcpy(&entry->buf, tbuffer, len); entry->buf[len] = '\0'; - if (!filter_check_discard(call, entry, buffer, event)) { + if (!call_filter_check_discard(call, entry, buffer, event)) { __buffer_unlock_commit(buffer, event); ftrace_trace_stack(buffer, flags, 6, pc); } diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index d1cf5159bec0..12d1a612a73e 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1007,9 +1007,9 @@ struct filter_pred { extern enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not); -extern void print_event_filter(struct ftrace_event_call *call, +extern void print_event_filter(struct ftrace_event_file *file, struct trace_seq *s); -extern int apply_event_filter(struct ftrace_event_call *call, +extern int apply_event_filter(struct ftrace_event_file *file, char *filter_string); extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, char *filter_string); @@ -1020,20 +1020,6 @@ extern int filter_assign_type(const char *type); struct ftrace_event_field * trace_find_event_field(struct ftrace_event_call *call, char *name); -static inline int -filter_check_discard(struct ftrace_event_call *call, void *rec, - struct ring_buffer *buffer, - struct ring_buffer_event *event) -{ - if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && - !filter_match_preds(call->filter, rec)) { - ring_buffer_discard_commit(buffer, event); - return 1; - } - - return 0; -} - extern void trace_event_enable_cmd_record(bool enable); extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); extern int event_trace_del_tracer(struct trace_array *tr); diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index d594da0dc03c..697fb9bac8f0 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -78,7 +78,7 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) entry->line = f->line; entry->correct = val == expect; - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); out: diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 368a4d50cc30..043f833246a0 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -989,7 +989,7 @@ static ssize_t event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call; + struct ftrace_event_file *file; struct trace_seq *s; int r = -ENODEV; @@ -1004,12 +1004,12 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, trace_seq_init(s); mutex_lock(&event_mutex); - call = event_file_data(filp); - if (call) - print_event_filter(call, s); + file = event_file_data(filp); + if (file) + print_event_filter(file, s); mutex_unlock(&event_mutex); - if (call) + if (file) r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len); kfree(s); @@ -1021,7 +1021,7 @@ static ssize_t event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call; + struct ftrace_event_file *file; char *buf; int err = -ENODEV; @@ -1039,9 +1039,9 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, buf[cnt] = '\0'; mutex_lock(&event_mutex); - call = event_file_data(filp); - if (call) - err = apply_event_filter(call, buf); + file = event_file_data(filp); + if (file) + err = apply_event_filter(file, buf); mutex_unlock(&event_mutex); free_page((unsigned long) buf); @@ -1539,7 +1539,7 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file) return -1; } } - trace_create_file("filter", 0644, file->dir, call, + trace_create_file("filter", 0644, file->dir, file, &ftrace_event_filter_fops); trace_create_file("format", 0444, file->dir, call, @@ -1577,6 +1577,7 @@ static void event_remove(struct ftrace_event_call *call) if (file->event_call != call) continue; ftrace_event_enable_disable(file, 0); + destroy_preds(file); /* * The do_for_each_event_file() is * a double loop. After finding the call for this @@ -1700,7 +1701,7 @@ static void __trace_remove_event_call(struct ftrace_event_call *call) { event_remove(call); trace_destroy_fields(call); - destroy_preds(call); + destroy_call_preds(call); } static int probe_remove_event_call(struct ftrace_event_call *call) diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 97daa8cf958d..2468f56dc5db 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -637,10 +637,18 @@ static void append_filter_err(struct filter_parse_state *ps, free_page((unsigned long) buf); } +static inline struct event_filter *event_filter(struct ftrace_event_file *file) +{ + if (file->event_call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + return file->event_call->filter; + else + return file->filter; +} + /* caller must hold event_mutex */ -void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s) +void print_event_filter(struct ftrace_event_file *file, struct trace_seq *s) { - struct event_filter *filter = call->filter; + struct event_filter *filter = event_filter(file); if (filter && filter->filter_string) trace_seq_printf(s, "%s\n", filter->filter_string); @@ -766,11 +774,21 @@ static void __free_preds(struct event_filter *filter) filter->n_preds = 0; } -static void filter_disable(struct ftrace_event_call *call) +static void call_filter_disable(struct ftrace_event_call *call) { call->flags &= ~TRACE_EVENT_FL_FILTERED; } +static void filter_disable(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call_filter_disable(call); + else + file->flags &= ~FTRACE_EVENT_FL_FILTERED; +} + static void __free_filter(struct event_filter *filter) { if (!filter) @@ -781,16 +799,30 @@ static void __free_filter(struct event_filter *filter) kfree(filter); } +void destroy_call_preds(struct ftrace_event_call *call) +{ + __free_filter(call->filter); + call->filter = NULL; +} + +static void destroy_file_preds(struct ftrace_event_file *file) +{ + __free_filter(file->filter); + file->filter = NULL; +} + /* - * Called when destroying the ftrace_event_call. - * The call is being freed, so we do not need to worry about - * the call being currently used. This is for module code removing + * Called when destroying the ftrace_event_file. + * The file is being freed, so we do not need to worry about + * the file being currently used. This is for module code removing * the tracepoints from within it. */ -void destroy_preds(struct ftrace_event_call *call) +void destroy_preds(struct ftrace_event_file *file) { - __free_filter(call->filter); - call->filter = NULL; + if (file->event_call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + destroy_call_preds(file->event_call); + else + destroy_file_preds(file); } static struct event_filter *__alloc_filter(void) @@ -825,28 +857,56 @@ static int __alloc_preds(struct event_filter *filter, int n_preds) return 0; } -static void filter_free_subsystem_preds(struct event_subsystem *system) +static inline void __remove_filter(struct ftrace_event_file *file) { + struct ftrace_event_call *call = file->event_call; + + filter_disable(file); + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + remove_filter_string(call->filter); + else + remove_filter_string(file->filter); +} + +static void filter_free_subsystem_preds(struct event_subsystem *system, + struct trace_array *tr) +{ + struct ftrace_event_file *file; struct ftrace_event_call *call; - list_for_each_entry(call, &ftrace_events, list) { + list_for_each_entry(file, &tr->events, list) { + call = file->event_call; if (strcmp(call->class->system, system->name) != 0) continue; - filter_disable(call); - remove_filter_string(call->filter); + __remove_filter(file); } } -static void filter_free_subsystem_filters(struct event_subsystem *system) +static inline void __free_subsystem_filter(struct ftrace_event_file *file) { + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) { + __free_filter(call->filter); + call->filter = NULL; + } else { + __free_filter(file->filter); + file->filter = NULL; + } +} + +static void filter_free_subsystem_filters(struct event_subsystem *system, + struct trace_array *tr) +{ + struct ftrace_event_file *file; struct ftrace_event_call *call; - list_for_each_entry(call, &ftrace_events, list) { + list_for_each_entry(file, &tr->events, list) { + call = file->event_call; if (strcmp(call->class->system, system->name) != 0) continue; - __free_filter(call->filter); - call->filter = NULL; + __free_subsystem_filter(file); } } @@ -1617,15 +1677,85 @@ fail: return err; } +static inline void event_set_filtered_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call->flags |= TRACE_EVENT_FL_FILTERED; + else + file->flags |= FTRACE_EVENT_FL_FILTERED; +} + +static inline void event_set_filter(struct ftrace_event_file *file, + struct event_filter *filter) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + rcu_assign_pointer(call->filter, filter); + else + rcu_assign_pointer(file->filter, filter); +} + +static inline void event_clear_filter(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + RCU_INIT_POINTER(call->filter, NULL); + else + RCU_INIT_POINTER(file->filter, NULL); +} + +static inline void +event_set_no_set_filter_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call->flags |= TRACE_EVENT_FL_NO_SET_FILTER; + else + file->flags |= FTRACE_EVENT_FL_NO_SET_FILTER; +} + +static inline void +event_clear_no_set_filter_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call->flags &= ~TRACE_EVENT_FL_NO_SET_FILTER; + else + file->flags &= ~FTRACE_EVENT_FL_NO_SET_FILTER; +} + +static inline bool +event_no_set_filter_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (file->flags & FTRACE_EVENT_FL_NO_SET_FILTER) + return true; + + if ((call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) && + (call->flags & TRACE_EVENT_FL_NO_SET_FILTER)) + return true; + + return false; +} + struct filter_list { struct list_head list; struct event_filter *filter; }; static int replace_system_preds(struct event_subsystem *system, + struct trace_array *tr, struct filter_parse_state *ps, char *filter_string) { + struct ftrace_event_file *file; struct ftrace_event_call *call; struct filter_list *filter_item; struct filter_list *tmp; @@ -1633,8 +1763,8 @@ static int replace_system_preds(struct event_subsystem *system, bool fail = true; int err; - list_for_each_entry(call, &ftrace_events, list) { - + list_for_each_entry(file, &tr->events, list) { + call = file->event_call; if (strcmp(call->class->system, system->name) != 0) continue; @@ -1644,18 +1774,20 @@ static int replace_system_preds(struct event_subsystem *system, */ err = replace_preds(call, NULL, ps, filter_string, true); if (err) - call->flags |= TRACE_EVENT_FL_NO_SET_FILTER; + event_set_no_set_filter_flag(file); else - call->flags &= ~TRACE_EVENT_FL_NO_SET_FILTER; + event_clear_no_set_filter_flag(file); } - list_for_each_entry(call, &ftrace_events, list) { + list_for_each_entry(file, &tr->events, list) { struct event_filter *filter; + call = file->event_call; + if (strcmp(call->class->system, system->name) != 0) continue; - if (call->flags & TRACE_EVENT_FL_NO_SET_FILTER) + if (event_no_set_filter_flag(file)) continue; filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL); @@ -1676,17 +1808,17 @@ static int replace_system_preds(struct event_subsystem *system, err = replace_preds(call, filter, ps, filter_string, false); if (err) { - filter_disable(call); + filter_disable(file); parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); append_filter_err(ps, filter); } else - call->flags |= TRACE_EVENT_FL_FILTERED; + event_set_filtered_flag(file); /* * Regardless of if this returned an error, we still * replace the filter for the call. */ - filter = call->filter; - rcu_assign_pointer(call->filter, filter_item->filter); + filter = event_filter(file); + event_set_filter(file, filter_item->filter); filter_item->filter = filter; fail = false; @@ -1816,6 +1948,7 @@ static int create_filter(struct ftrace_event_call *call, * and always remembers @filter_str. */ static int create_system_filter(struct event_subsystem *system, + struct trace_array *tr, char *filter_str, struct event_filter **filterp) { struct event_filter *filter = NULL; @@ -1824,7 +1957,7 @@ static int create_system_filter(struct event_subsystem *system, err = create_filter_start(filter_str, true, &ps, &filter); if (!err) { - err = replace_system_preds(system, ps, filter_str); + err = replace_system_preds(system, tr, ps, filter_str); if (!err) { /* System filters just show a default message */ kfree(filter->filter_string); @@ -1840,20 +1973,25 @@ static int create_system_filter(struct event_subsystem *system, } /* caller must hold event_mutex */ -int apply_event_filter(struct ftrace_event_call *call, char *filter_string) +int apply_event_filter(struct ftrace_event_file *file, char *filter_string) { + struct ftrace_event_call *call = file->event_call; struct event_filter *filter; int err; if (!strcmp(strstrip(filter_string), "0")) { - filter_disable(call); - filter = call->filter; + filter_disable(file); + filter = event_filter(file); + if (!filter) return 0; - RCU_INIT_POINTER(call->filter, NULL); + + event_clear_filter(file); + /* Make sure the filter is not being used */ synchronize_sched(); __free_filter(filter); + return 0; } @@ -1866,14 +2004,15 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string) * string */ if (filter) { - struct event_filter *tmp = call->filter; + struct event_filter *tmp; + tmp = event_filter(file); if (!err) - call->flags |= TRACE_EVENT_FL_FILTERED; + event_set_filtered_flag(file); else - filter_disable(call); + filter_disable(file); - rcu_assign_pointer(call->filter, filter); + event_set_filter(file, filter); if (tmp) { /* Make sure the call is done with the filter */ @@ -1889,6 +2028,7 @@ int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, char *filter_string) { struct event_subsystem *system = dir->subsystem; + struct trace_array *tr = dir->tr; struct event_filter *filter; int err = 0; @@ -1901,18 +2041,18 @@ int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, } if (!strcmp(strstrip(filter_string), "0")) { - filter_free_subsystem_preds(system); + filter_free_subsystem_preds(system, tr); remove_filter_string(system->filter); filter = system->filter; system->filter = NULL; /* Ensure all filters are no longer used */ synchronize_sched(); - filter_free_subsystem_filters(system); + filter_free_subsystem_filters(system, tr); __free_filter(filter); goto out_unlock; } - err = create_system_filter(system, filter_string, &filter); + err = create_system_filter(system, tr, filter_string, &filter); if (filter) { /* * No event actually uses the system filter diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index d21a74670088..7c3e3e72e2b6 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -180,7 +180,7 @@ struct ftrace_event_call __used event_##call = { \ .event.type = etype, \ .class = &event_class_ftrace_##call, \ .print_fmt = print, \ - .flags = TRACE_EVENT_FL_IGNORE_ENABLE, \ + .flags = TRACE_EVENT_FL_IGNORE_ENABLE | TRACE_EVENT_FL_USE_CALL_FILTER, \ }; \ struct ftrace_event_call __used \ __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call; diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index e08c030b8f38..80387d1d27e1 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -270,7 +270,7 @@ int __trace_graph_entry(struct trace_array *tr, return 0; entry = ring_buffer_event_data(event); entry->graph_ent = *trace; - if (!filter_current_check_discard(buffer, call, entry, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); return 1; @@ -385,7 +385,7 @@ void __trace_graph_return(struct trace_array *tr, return; entry = ring_buffer_event_data(event); entry->ret = *trace; - if (!filter_current_check_discard(buffer, call, entry, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 243f6834d026..dae9541ada9e 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -835,7 +835,7 @@ __kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, entry->ip = (unsigned long)tp->rp.kp.addr; store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); - if (!filter_current_check_discard(buffer, call, entry, event)) + if (!filter_check_discard(ftrace_file, entry, buffer, event)) trace_buffer_unlock_commit_regs(buffer, event, irq_flags, pc, regs); } @@ -884,7 +884,7 @@ __kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, entry->ret_ip = (unsigned long)ri->ret_addr; store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); - if (!filter_current_check_discard(buffer, call, entry, event)) + if (!filter_check_discard(ftrace_file, entry, buffer, event)) trace_buffer_unlock_commit_regs(buffer, event, irq_flags, pc, regs); } diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index b3dcfb2f0fef..0abd9b863474 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -323,7 +323,7 @@ static void __trace_mmiotrace_rw(struct trace_array *tr, entry = ring_buffer_event_data(event); entry->rw = *rw; - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) trace_buffer_unlock_commit(buffer, event, 0, pc); } @@ -353,7 +353,7 @@ static void __trace_mmiotrace_map(struct trace_array *tr, entry = ring_buffer_event_data(event); entry->map = *map; - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) trace_buffer_unlock_commit(buffer, event, 0, pc); } diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index 4e98e3b257a3..3f34dc9b40f3 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -45,7 +45,7 @@ tracing_sched_switch_trace(struct trace_array *tr, entry->next_state = next->state; entry->next_cpu = task_cpu(next); - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) trace_buffer_unlock_commit(buffer, event, flags, pc); } @@ -101,7 +101,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr, entry->next_state = wakee->state; entry->next_cpu = task_cpu(wakee); - if (!filter_check_discard(call, entry, buffer, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) trace_buffer_unlock_commit(buffer, event, flags, pc); } diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 559329d9bd2f..32644eece429 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -336,8 +336,8 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) entry->nr = syscall_nr; syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); - if (!filter_current_check_discard(buffer, sys_data->enter_event, - entry, event)) + if (!call_filter_check_discard(sys_data->enter_event, entry, + buffer, event)) trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc); } @@ -377,8 +377,8 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) entry->nr = syscall_nr; entry->ret = syscall_get_return_value(current, regs); - if (!filter_current_check_discard(buffer, sys_data->exit_event, - entry, event)) + if (!call_filter_check_discard(sys_data->exit_event, entry, + buffer, event)) trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc); } diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 272261b5f94f..b6dcc42ef7f5 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -128,6 +128,7 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) if (is_ret) tu->consumer.ret_handler = uretprobe_dispatcher; init_trace_uprobe_filter(&tu->filter); + tu->call.flags |= TRACE_EVENT_FL_USE_CALL_FILTER; return tu; error: @@ -561,7 +562,7 @@ static void uprobe_trace_print(struct trace_uprobe *tu, for (i = 0; i < tu->nr_args; i++) call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset); - if (!filter_current_check_discard(buffer, call, entry, event)) + if (!call_filter_check_discard(call, entry, buffer, event)) trace_buffer_unlock_commit(buffer, event, 0, 0); } -- cgit v1.2.3 From 38de93abec8d8acd8d6dbbe9b0d92d6d5cdb3090 Mon Sep 17 00:00:00 2001 From: Tom Zanussi Date: Thu, 24 Oct 2013 08:34:18 -0500 Subject: tracing: Make register/unregister_ftrace_command __init register/unregister_ftrace_command() are only ever called from __init functions, so can themselves be made __init. Also make register_snapshot_cmd() __init for the same reason. Link: http://lkml.kernel.org/r/d4042c8cadb7ae6f843ac9a89a24e1c6a3099727.1382620672.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt --- include/linux/ftrace.h | 4 ++-- kernel/trace/ftrace.c | 12 ++++++++++-- kernel/trace/trace.c | 4 ++-- 3 files changed, 14 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index ec85d48619e1..31ea4b428360 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -533,11 +533,11 @@ static inline int ftrace_force_update(void) { return 0; } static inline void ftrace_disable_daemon(void) { } static inline void ftrace_enable_daemon(void) { } static inline void ftrace_release_mod(struct module *mod) {} -static inline int register_ftrace_command(struct ftrace_func_command *cmd) +static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) { return -EINVAL; } -static inline int unregister_ftrace_command(char *cmd_name) +static inline __init int unregister_ftrace_command(char *cmd_name) { return -EINVAL; } diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 080b7d41e17f..22fa55696760 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3307,7 +3307,11 @@ void unregister_ftrace_function_probe_all(char *glob) static LIST_HEAD(ftrace_commands); static DEFINE_MUTEX(ftrace_cmd_mutex); -int register_ftrace_command(struct ftrace_func_command *cmd) +/* + * Currently we only register ftrace commands from __init, so mark this + * __init too. + */ +__init int register_ftrace_command(struct ftrace_func_command *cmd) { struct ftrace_func_command *p; int ret = 0; @@ -3326,7 +3330,11 @@ int register_ftrace_command(struct ftrace_func_command *cmd) return ret; } -int unregister_ftrace_command(struct ftrace_func_command *cmd) +/* + * Currently we only unregister ftrace commands from __init, so mark + * this __init too. + */ +__init int unregister_ftrace_command(struct ftrace_func_command *cmd) { struct ftrace_func_command *p, *n; int ret = -ENODEV; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 489da8b19f30..f9fa42b180e3 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5477,12 +5477,12 @@ static struct ftrace_func_command ftrace_snapshot_cmd = { .func = ftrace_trace_snapshot_callback, }; -static int register_snapshot_cmd(void) +static __init int register_snapshot_cmd(void) { return register_ftrace_command(&ftrace_snapshot_cmd); } #else -static inline int register_snapshot_cmd(void) { return 0; } +static inline __init int register_snapshot_cmd(void) { return 0; } #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ struct dentry *tracing_init_dentry_tr(struct trace_array *tr) -- cgit v1.2.3 From d562aff93bfb530b0992141500a402d17081189d Mon Sep 17 00:00:00 2001 From: Tom Zanussi Date: Thu, 24 Oct 2013 08:34:19 -0500 Subject: tracing: Add support for SOFT_DISABLE to syscall events The original SOFT_DISABLE patches didn't add support for soft disable of syscall events; this adds it. Add an array of ftrace_event_file pointers indexed by syscall number to the trace array and remove the existing enabled bitmaps, which as a result are now redundant. The ftrace_event_file structs in turn contain the soft disable flags we need for per-syscall soft disable accounting. Adding ftrace_event_files also means we can remove the USE_CALL_FILTER bit, thus enabling multibuffer filter support for syscall events. Link: http://lkml.kernel.org/r/6e72b566e85d8df8042f133efbc6c30e21fb017e.1382620672.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt --- include/linux/syscalls.h | 4 ++-- kernel/trace/trace.h | 4 ++-- kernel/trace/trace_syscalls.c | 42 ++++++++++++++++++++++++++++++++---------- 3 files changed, 36 insertions(+), 14 deletions(-) (limited to 'include/linux') diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 10bafa97049d..2ef31bfd620b 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -120,7 +120,7 @@ extern struct trace_event_functions exit_syscall_print_funcs; .class = &event_class_syscall_enter, \ .event.funcs = &enter_syscall_print_funcs, \ .data = (void *)&__syscall_meta_##sname,\ - .flags = TRACE_EVENT_FL_CAP_ANY | TRACE_EVENT_FL_USE_CALL_FILTER,\ + .flags = TRACE_EVENT_FL_CAP_ANY, \ }; \ static struct ftrace_event_call __used \ __attribute__((section("_ftrace_events"))) \ @@ -134,7 +134,7 @@ extern struct trace_event_functions exit_syscall_print_funcs; .class = &event_class_syscall_exit, \ .event.funcs = &exit_syscall_print_funcs, \ .data = (void *)&__syscall_meta_##sname,\ - .flags = TRACE_EVENT_FL_CAP_ANY | TRACE_EVENT_FL_USE_CALL_FILTER,\ + .flags = TRACE_EVENT_FL_CAP_ANY, \ }; \ static struct ftrace_event_call __used \ __attribute__((section("_ftrace_events"))) \ diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 12d1a612a73e..9c27cdadd71f 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -192,8 +192,8 @@ struct trace_array { #ifdef CONFIG_FTRACE_SYSCALLS int sys_refcount_enter; int sys_refcount_exit; - DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls); - DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls); + struct ftrace_event_file *enter_syscall_files[NR_syscalls]; + struct ftrace_event_file *exit_syscall_files[NR_syscalls]; #endif int stop_count; int clock_id; diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 32644eece429..e4b6d11bdf78 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -302,6 +302,7 @@ static int __init syscall_exit_define_fields(struct ftrace_event_call *call) static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) { struct trace_array *tr = data; + struct ftrace_event_file *ftrace_file; struct syscall_trace_enter *entry; struct syscall_metadata *sys_data; struct ring_buffer_event *event; @@ -314,7 +315,13 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) syscall_nr = trace_get_syscall_nr(current, regs); if (syscall_nr < 0) return; - if (!test_bit(syscall_nr, tr->enabled_enter_syscalls)) + + /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */ + ftrace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]); + if (!ftrace_file) + return; + + if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) return; sys_data = syscall_nr_to_meta(syscall_nr); @@ -336,8 +343,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) entry->nr = syscall_nr; syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); - if (!call_filter_check_discard(sys_data->enter_event, entry, - buffer, event)) + if (!filter_check_discard(ftrace_file, entry, buffer, event)) trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc); } @@ -345,6 +351,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) { struct trace_array *tr = data; + struct ftrace_event_file *ftrace_file; struct syscall_trace_exit *entry; struct syscall_metadata *sys_data; struct ring_buffer_event *event; @@ -356,7 +363,13 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) syscall_nr = trace_get_syscall_nr(current, regs); if (syscall_nr < 0) return; - if (!test_bit(syscall_nr, tr->enabled_exit_syscalls)) + + /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */ + ftrace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]); + if (!ftrace_file) + return; + + if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) return; sys_data = syscall_nr_to_meta(syscall_nr); @@ -377,8 +390,7 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) entry->nr = syscall_nr; entry->ret = syscall_get_return_value(current, regs); - if (!call_filter_check_discard(sys_data->exit_event, entry, - buffer, event)) + if (!filter_check_discard(ftrace_file, entry, buffer, event)) trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc); } @@ -397,7 +409,7 @@ static int reg_event_syscall_enter(struct ftrace_event_file *file, if (!tr->sys_refcount_enter) ret = register_trace_sys_enter(ftrace_syscall_enter, tr); if (!ret) { - set_bit(num, tr->enabled_enter_syscalls); + rcu_assign_pointer(tr->enter_syscall_files[num], file); tr->sys_refcount_enter++; } mutex_unlock(&syscall_trace_lock); @@ -415,10 +427,15 @@ static void unreg_event_syscall_enter(struct ftrace_event_file *file, return; mutex_lock(&syscall_trace_lock); tr->sys_refcount_enter--; - clear_bit(num, tr->enabled_enter_syscalls); + rcu_assign_pointer(tr->enter_syscall_files[num], NULL); if (!tr->sys_refcount_enter) unregister_trace_sys_enter(ftrace_syscall_enter, tr); mutex_unlock(&syscall_trace_lock); + /* + * Callers expect the event to be completely disabled on + * return, so wait for current handlers to finish. + */ + synchronize_sched(); } static int reg_event_syscall_exit(struct ftrace_event_file *file, @@ -435,7 +452,7 @@ static int reg_event_syscall_exit(struct ftrace_event_file *file, if (!tr->sys_refcount_exit) ret = register_trace_sys_exit(ftrace_syscall_exit, tr); if (!ret) { - set_bit(num, tr->enabled_exit_syscalls); + rcu_assign_pointer(tr->exit_syscall_files[num], file); tr->sys_refcount_exit++; } mutex_unlock(&syscall_trace_lock); @@ -453,10 +470,15 @@ static void unreg_event_syscall_exit(struct ftrace_event_file *file, return; mutex_lock(&syscall_trace_lock); tr->sys_refcount_exit--; - clear_bit(num, tr->enabled_exit_syscalls); + rcu_assign_pointer(tr->exit_syscall_files[num], NULL); if (!tr->sys_refcount_exit) unregister_trace_sys_exit(ftrace_syscall_exit, tr); mutex_unlock(&syscall_trace_lock); + /* + * Callers expect the event to be completely disabled on + * return, so wait for current handlers to finish. + */ + synchronize_sched(); } static int __init init_syscall_trace(struct ftrace_event_call *call) -- cgit v1.2.3 From 042b10d83d05174e50ee861ee3aca55fd6204324 Mon Sep 17 00:00:00 2001 From: Steven Rostedt (Red Hat) Date: Wed, 6 Nov 2013 12:19:37 -0500 Subject: tracing: Remove unused function ftrace_off_permanent() In the past, ftrace_off_permanent() was called if something strange was detected. But the ftrace_bug() now handles all the anomolies that can happen with ftrace (function tracing), and there are no uses of ftrace_off_permanent(). Get rid of it. Signed-off-by: Steven Rostedt --- include/linux/kernel.h | 2 -- kernel/trace/trace.c | 15 --------------- 2 files changed, 17 deletions(-) (limited to 'include/linux') diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 672ddc4de4af..d4e98d13eff4 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -501,7 +501,6 @@ void tracing_snapshot_alloc(void); extern void tracing_start(void); extern void tracing_stop(void); -extern void ftrace_off_permanent(void); static inline __printf(1, 2) void ____trace_printk_check_format(const char *fmt, ...) @@ -639,7 +638,6 @@ extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); #else static inline void tracing_start(void) { } static inline void tracing_stop(void) { } -static inline void ftrace_off_permanent(void) { } static inline void trace_dump_stack(int skip) { } static inline void tracing_on(void) { } diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 2a595cf14f1c..d72a15c0b32c 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1283,21 +1283,6 @@ int is_tracing_stopped(void) return global_trace.stop_count; } -/** - * ftrace_off_permanent - disable all ftrace code permanently - * - * This should only be called when a serious anomally has - * been detected. This will turn off the function tracing, - * ring buffers, and other tracing utilites. It takes no - * locks and can be called from any context. - */ -void ftrace_off_permanent(void) -{ - tracing_disabled = 1; - ftrace_stop(); - tracing_off_permanent(); -} - /** * tracing_start - quick start of the tracer * -- cgit v1.2.3