Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756893AbZCaFtK (ORCPT ); Tue, 31 Mar 2009 01:49:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754582AbZCaFsz (ORCPT ); Tue, 31 Mar 2009 01:48:55 -0400 Received: from mail-qy0-f118.google.com ([209.85.221.118]:45171 "EHLO mail-qy0-f118.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752457AbZCaFsy (ORCPT ); Tue, 31 Mar 2009 01:48:54 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:content-type:date:message-id:mime-version :x-mailer:content-transfer-encoding; b=g7zgFy9zoSKM79IA4hS6JrG73+ljlFyTZxSipwJsrMPDQZdcSynm7Sq0xvuFpLjjm4 a8rCOysxw0XFxqiNWbvd/8IIYK8AQ34IG0RaMoL0ZKLdSuOinLYTnixgSKr1iiRMGRSU sioFUDSGZBwPVCKtQ+MOiXHDSewgfRRPPf6DI= Subject: [PATCH v2] tracing/filters: add run-time field descriptions to TRACE_EVENT_FORMAT events From: Tom Zanussi To: linux-kernel Cc: Ingo Molnar , Steven Rostedt , fweisbec@gmail.com Content-Type: text/plain Date: Tue, 31 Mar 2009 00:48:49 -0500 Message-Id: <1238478529.6749.12.camel@bookworm> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 19176 Lines: 546 This patch adds run-time field descriptions to all the event formats exported using TRACE_EVENT_FORMAT. It also hooks up all the tracers that use them (i.e. the tracers in the 'ftrace subsystem') so they can also have their output filtered by the event-filtering mechanism. When I was testing this, there were a couple of things that fooled me into thinking the filters weren't working, when actually they were - I'll mention them here so others don't make the same mistakes (and file bug reports. ;-) One is that some of the tracers trace multiple events e.g. the sched_switch tracer uses the context_switch and wakeup events, and if you don't set filters on all of the traced events, the unfiltered output from the events without filters on them can make it look like the filtering as a whole isn't working properly, when actually it is doing what it was asked to do - it just wasn't asked to do the right thing. The other is that for the really high-volume tracers e.g. the function tracer, the volume of filtered events can be so high that it pushes the unfiltered events out of the ring buffer before they can be read so e.g. cat'ing the trace file repeatedly shows either no output, or once in awhile some output but that isn't there the next time you read the trace, which isn't what you normally expect when reading the trace file. If you read from the trace_pipe file though, you can catch them before they disappear. Changes from v1: As suggested by Frederic Weisbecker: - get rid of externs in functions - added unlikely() to filter_check_discard() Signed-off-by: Tom Zanussi --- kernel/trace/kmemtrace.c | 6 ++++ kernel/trace/trace.c | 25 +++++++++++++++ kernel/trace/trace.h | 20 ++++++++++++ kernel/trace/trace_branch.c | 3 ++ kernel/trace/trace_event_types.h | 6 ++- kernel/trace/trace_events.c | 7 ++++ kernel/trace/trace_events_filter.c | 4 +- kernel/trace/trace_events_stage_2.h | 7 ---- kernel/trace/trace_export.c | 57 +++++++++++++++++++++++++++++++++-- kernel/trace/trace_hw_branches.c | 2 + kernel/trace/trace_power.c | 4 ++ 11 files changed, 127 insertions(+), 14 deletions(-) diff --git a/kernel/trace/kmemtrace.c b/kernel/trace/kmemtrace.c index 5011f4d..65aba48 100644 --- a/kernel/trace/kmemtrace.c +++ b/kernel/trace/kmemtrace.c @@ -42,6 +42,7 @@ static inline void kmemtrace_alloc(enum kmemtrace_type_id type_id, gfp_t gfp_flags, int node) { + struct ftrace_event_call *call = &event_kmem_alloc; struct trace_array *tr = kmemtrace_array; struct kmemtrace_alloc_entry *entry; struct ring_buffer_event *event; @@ -62,6 +63,8 @@ static inline void kmemtrace_alloc(enum kmemtrace_type_id type_id, entry->gfp_flags = gfp_flags; entry->node = node; + filter_check_discard(call, entry, event); + ring_buffer_unlock_commit(tr->buffer, event); trace_wake_up(); @@ -71,6 +74,7 @@ static inline void kmemtrace_free(enum kmemtrace_type_id type_id, unsigned long call_site, const void *ptr) { + struct ftrace_event_call *call = &event_kmem_free; struct trace_array *tr = kmemtrace_array; struct kmemtrace_free_entry *entry; struct ring_buffer_event *event; @@ -86,6 +90,8 @@ static inline void kmemtrace_free(enum kmemtrace_type_id type_id, entry->call_site = call_site; entry->ptr = ptr; + filter_check_discard(call, entry, event); + ring_buffer_unlock_commit(tr->buffer, event); trace_wake_up(); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 2a81dec..39b5de1 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -898,6 +898,7 @@ trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc) { + struct ftrace_event_call *call = &event_function; struct ring_buffer_event *event; struct ftrace_entry *entry; @@ -912,6 +913,9 @@ trace_function(struct trace_array *tr, entry = ring_buffer_event_data(event); entry->ip = ip; entry->parent_ip = parent_ip; + + filter_check_discard(call, entry, event); + ring_buffer_unlock_commit(tr->buffer, event); } @@ -921,6 +925,7 @@ static int __trace_graph_entry(struct trace_array *tr, unsigned long flags, int pc) { + struct ftrace_event_call *call = &event_funcgraph_entry; struct ring_buffer_event *event; struct ftrace_graph_ent_entry *entry; @@ -933,6 +938,7 @@ static int __trace_graph_entry(struct trace_array *tr, return 0; entry = ring_buffer_event_data(event); entry->graph_ent = *trace; + filter_check_discard(call, entry, event); ring_buffer_unlock_commit(global_trace.buffer, event); return 1; @@ -943,6 +949,7 @@ static void __trace_graph_return(struct trace_array *tr, unsigned long flags, int pc) { + struct ftrace_event_call *call = &event_funcgraph_exit; struct ring_buffer_event *event; struct ftrace_graph_ret_entry *entry; @@ -955,6 +962,7 @@ static void __trace_graph_return(struct trace_array *tr, return; entry = ring_buffer_event_data(event); entry->ret = *trace; + filter_check_discard(call, entry, event); ring_buffer_unlock_commit(global_trace.buffer, event); } #endif @@ -973,6 +981,7 @@ static void __ftrace_trace_stack(struct trace_array *tr, int skip, int pc) { #ifdef CONFIG_STACKTRACE + struct ftrace_event_call *call = &event_kernel_stack; struct ring_buffer_event *event; struct stack_entry *entry; struct stack_trace trace; @@ -990,6 +999,7 @@ static void __ftrace_trace_stack(struct trace_array *tr, trace.entries = entry->caller; save_stack_trace(&trace); + filter_check_discard(call, entry, event); ring_buffer_unlock_commit(tr->buffer, event); #endif } @@ -1015,6 +1025,7 @@ static void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) { #ifdef CONFIG_STACKTRACE + struct ftrace_event_call *call = &event_user_stack; struct ring_buffer_event *event; struct userstack_entry *entry; struct stack_trace trace; @@ -1036,6 +1047,7 @@ static void ftrace_trace_userstack(struct trace_array *tr, trace.entries = entry->caller; save_stack_trace_user(&trace); + filter_check_discard(call, entry, event); ring_buffer_unlock_commit(tr->buffer, event); #endif } @@ -1052,6 +1064,7 @@ ftrace_trace_special(void *__tr, unsigned long arg1, unsigned long arg2, unsigned long arg3, int pc) { + struct ftrace_event_call *call = &event_special; struct ring_buffer_event *event; struct trace_array *tr = __tr; struct special_entry *entry; @@ -1064,6 +1077,7 @@ ftrace_trace_special(void *__tr, entry->arg1 = arg1; entry->arg2 = arg2; entry->arg3 = arg3; + filter_check_discard(call, entry, event); trace_buffer_unlock_commit(tr, event, 0, pc); } @@ -1080,6 +1094,7 @@ tracing_sched_switch_trace(struct trace_array *tr, struct task_struct *next, unsigned long flags, int pc) { + struct ftrace_event_call *call = &event_context_switch; struct ring_buffer_event *event; struct ctx_switch_entry *entry; @@ -1095,6 +1110,9 @@ tracing_sched_switch_trace(struct trace_array *tr, entry->next_prio = next->prio; entry->next_state = next->state; entry->next_cpu = task_cpu(next); + + filter_check_discard(call, entry, event); + trace_buffer_unlock_commit(tr, event, flags, pc); } @@ -1104,6 +1122,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr, struct task_struct *curr, unsigned long flags, int pc) { + struct ftrace_event_call *call = &event_wakeup; struct ring_buffer_event *event; struct ctx_switch_entry *entry; @@ -1120,6 +1139,8 @@ tracing_sched_wakeup_trace(struct trace_array *tr, entry->next_state = wakee->state; entry->next_cpu = task_cpu(wakee); + filter_check_discard(call, entry, event); + ring_buffer_unlock_commit(tr->buffer, event); ftrace_trace_stack(tr, flags, 6, pc); ftrace_trace_userstack(tr, flags, pc); @@ -1221,6 +1242,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; static u32 trace_buf[TRACE_BUF_SIZE]; + struct ftrace_event_call *call = &event_bprint; struct ring_buffer_event *event; struct trace_array *tr = &global_trace; struct trace_array_cpu *data; @@ -1260,6 +1282,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) entry->fmt = fmt; memcpy(entry->buf, trace_buf, sizeof(u32) * len); + filter_check_discard(call, entry, event); ring_buffer_unlock_commit(tr->buffer, event); out_unlock: @@ -1279,6 +1302,7 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args) static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; static char trace_buf[TRACE_BUF_SIZE]; + struct ftrace_event_call *call = &event_print; struct ring_buffer_event *event; struct trace_array *tr = &global_trace; struct trace_array_cpu *data; @@ -1314,6 +1338,7 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args) memcpy(&entry->buf, trace_buf, len); entry->buf[len] = 0; + filter_check_discard(call, entry, event); ring_buffer_unlock_commit(tr->buffer, event); out_unlock: diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index fec6521..f56c628 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -860,6 +860,21 @@ extern void filter_free_subsystem_preds(struct event_subsystem *system); extern int filter_add_subsystem_pred(struct event_subsystem *system, struct filter_pred *pred); +static inline void +filter_check_discard(struct ftrace_event_call *call, void *rec, + struct ring_buffer_event *event) +{ + if (unlikely(call->preds) && !filter_match_preds(call, rec)) + ring_buffer_event_discard(event); +} + +#define __common_field(type, item) \ + ret = trace_define_field(event_call, #type, "common_" #item, \ + offsetof(typeof(field.ent), item), \ + sizeof(field.ent.item)); \ + if (ret) \ + return ret; + void event_trace_printk(unsigned long ip, const char *fmt, ...); extern struct ftrace_event_call __start_ftrace_events[]; extern struct ftrace_event_call __stop_ftrace_events[]; @@ -891,4 +906,9 @@ do { \ __trace_printk(ip, fmt, ##args); \ } while (0) +#undef TRACE_EVENT_FORMAT +#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ + extern struct ftrace_event_call event_##call; +#include "trace_event_types.h" + #endif /* _LINUX_KERNEL_TRACE_H */ diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index e6e3291..c95c25d 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -30,6 +30,7 @@ static struct trace_array *branch_tracer; static void probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) { + struct ftrace_event_call *call = &event_branch; struct trace_array *tr = branch_tracer; struct ring_buffer_event *event; struct trace_branch *entry; @@ -73,6 +74,8 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) entry->line = f->line; entry->correct = val == expect; + filter_check_discard(call, entry, event); + ring_buffer_unlock_commit(tr->buffer, event); out: diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h index fd78bee..95b147a 100644 --- a/kernel/trace/trace_event_types.h +++ b/kernel/trace/trace_event_types.h @@ -122,8 +122,10 @@ TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore, TRACE_EVENT_FORMAT(branch, TRACE_BRANCH, trace_branch, ignore, TRACE_STRUCT( TRACE_FIELD(unsigned int, line, line) - TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE+1], func, func) - TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE+1], file, file) + TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE+1], func, + TRACE_FUNC_SIZE+1, func) + TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE+1], file, + TRACE_FUNC_SIZE+1, file) TRACE_FIELD(char, correct, correct) ), TP_RAW_FMT("%u:%s:%s (%u)") diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 64ec4d2..be9299a 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -680,6 +680,7 @@ static struct dentry * event_subsystem_dir(const char *name, struct dentry *d_events) { struct event_subsystem *system; + struct dentry *entry; /* First see if we did not already create this dir */ list_for_each_entry(system, &event_subsystems, list) { @@ -708,6 +709,12 @@ event_subsystem_dir(const char *name, struct dentry *d_events) system->preds = NULL; + entry = debugfs_create_file("filter", 0644, system->entry, system, + &ftrace_subsystem_filter_fops); + if (!entry) + pr_warning("Could not create debugfs " + "'%s/filter' entry\n", name); + return system->entry; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 026be41..470ad94 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -185,7 +185,7 @@ void filter_free_subsystem_preds(struct event_subsystem *system) } events_for_each(call) { - if (!call->name || !call->regfunc) + if (!call->define_fields) continue; if (!strcmp(call->system, system->name)) @@ -324,7 +324,7 @@ int filter_add_subsystem_pred(struct event_subsystem *system, events_for_each(call) { int err; - if (!call->name || !call->regfunc) + if (!call->define_fields) continue; if (strcmp(call->system, system->name)) diff --git a/kernel/trace/trace_events_stage_2.h b/kernel/trace/trace_events_stage_2.h index 30743f7..1c94b87 100644 --- a/kernel/trace/trace_events_stage_2.h +++ b/kernel/trace/trace_events_stage_2.h @@ -146,13 +146,6 @@ ftrace_format_##call(struct trace_seq *s) \ if (ret) \ return ret; -#define __common_field(type, item) \ - ret = trace_define_field(event_call, #type, "common_" #item, \ - offsetof(typeof(field.ent), item), \ - sizeof(field.ent.item)); \ - if (ret) \ - return ret; - #undef TRACE_EVENT #define TRACE_EVENT(call, proto, args, tstruct, func, print) \ int \ diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index 4d9952d..47989be 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -30,7 +30,7 @@ #undef TRACE_FIELD_SPECIAL -#define TRACE_FIELD_SPECIAL(type_item, item, cmd) \ +#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd) \ ret = trace_seq_printf(s, "\tfield special:" #type_item ";\t" \ "offset:%u;\tsize:%u;\n", \ (unsigned int)offsetof(typeof(field), item), \ @@ -85,18 +85,69 @@ ftrace_format_##call(struct trace_seq *s) \ #define TRACE_ENTRY entry #undef TRACE_FIELD_SPECIAL -#define TRACE_FIELD_SPECIAL(type_item, item, cmd) \ +#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd) \ cmd; #undef TRACE_EVENT_FORMAT #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ +int ftrace_define_fields_##call(void); \ +static int ftrace_raw_init_event_##call(void); \ \ -static struct ftrace_event_call __used \ +struct ftrace_event_call __used \ __attribute__((__aligned__(4))) \ __attribute__((section("_ftrace_events"))) event_##call = { \ .name = #call, \ .id = proto, \ .system = __stringify(TRACE_SYSTEM), \ + .raw_init = ftrace_raw_init_event_##call, \ .show_format = ftrace_format_##call, \ + .define_fields = ftrace_define_fields_##call, \ +}; \ +static int ftrace_raw_init_event_##call(void) \ +{ \ + INIT_LIST_HEAD(&event_##call.fields); \ + return 0; \ +} \ + +#include "trace_event_types.h" + +#undef TRACE_FIELD +#define TRACE_FIELD(type, item, assign) \ + ret = trace_define_field(event_call, #type, #item, \ + offsetof(typeof(field), item), \ + sizeof(field.item)); \ + if (ret) \ + return ret; + +#undef TRACE_FIELD_SPECIAL +#define TRACE_FIELD_SPECIAL(type, item, len, cmd) \ + ret = trace_define_field(event_call, #type "[" #len "]", #item, \ + offsetof(typeof(field), item), \ + sizeof(field.item)); \ + if (ret) \ + return ret; + +#undef TRACE_FIELD_ZERO_CHAR +#define TRACE_FIELD_ZERO_CHAR(item) + +#undef TRACE_EVENT_FORMAT +#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ +int \ +ftrace_define_fields_##call(void) \ +{ \ + struct ftrace_event_call *event_call = &event_##call; \ + struct args field; \ + int ret; \ + \ + __common_field(unsigned char, type); \ + __common_field(unsigned char, flags); \ + __common_field(unsigned char, preempt_count); \ + __common_field(int, pid); \ + __common_field(int, tgid); \ + \ + tstruct; \ + \ + return ret; \ } + #include "trace_event_types.h" diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c index 7bfdf4c..e6b275b 100644 --- a/kernel/trace/trace_hw_branches.c +++ b/kernel/trace/trace_hw_branches.c @@ -168,6 +168,7 @@ static enum print_line_t bts_trace_print_line(struct trace_iterator *iter) void trace_hw_branch(u64 from, u64 to) { + struct ftrace_event_call *call = &event_hw_branch; struct trace_array *tr = hw_branch_trace; struct ring_buffer_event *event; struct hw_branch_entry *entry; @@ -194,6 +195,7 @@ void trace_hw_branch(u64 from, u64 to) entry->ent.type = TRACE_HW_BRANCHES; entry->from = from; entry->to = to; + filter_check_discard(call, entry, event); trace_buffer_unlock_commit(tr, event, 0, 0); out: diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c index bae791e..8ce7d7d 100644 --- a/kernel/trace/trace_power.c +++ b/kernel/trace/trace_power.c @@ -36,6 +36,7 @@ static void probe_power_start(struct power_trace *it, unsigned int type, static void probe_power_end(struct power_trace *it) { + struct ftrace_event_call *call = &event_power; struct ring_buffer_event *event; struct trace_power *entry; struct trace_array_cpu *data; @@ -54,6 +55,7 @@ static void probe_power_end(struct power_trace *it) goto out; entry = ring_buffer_event_data(event); entry->state_data = *it; + filter_check_discard(call, entry, event); trace_buffer_unlock_commit(tr, event, 0, 0); out: preempt_enable(); @@ -62,6 +64,7 @@ static void probe_power_end(struct power_trace *it) static void probe_power_mark(struct power_trace *it, unsigned int type, unsigned int level) { + struct ftrace_event_call *call = &event_power; struct ring_buffer_event *event; struct trace_power *entry; struct trace_array_cpu *data; @@ -84,6 +87,7 @@ static void probe_power_mark(struct power_trace *it, unsigned int type, goto out; entry = ring_buffer_event_data(event); entry->state_data = *it; + filter_check_discard(call, entry, event); trace_buffer_unlock_commit(tr, event, 0, 0); out: preempt_enable(); -- 1.5.6.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/