Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752590AbZGTCWl (ORCPT ); Sun, 19 Jul 2009 22:22:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752471AbZGTCWj (ORCPT ); Sun, 19 Jul 2009 22:22:39 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:52272 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751553AbZGTCWi (ORCPT ); Sun, 19 Jul 2009 22:22:38 -0400 Message-ID: <4A63D485.7030703@cn.fujitsu.com> Date: Mon, 20 Jul 2009 10:20:53 +0800 From: Li Zefan User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1b3pre) Gecko/20090513 Fedora/3.0-2.3.beta2.fc11 Thunderbird/3.0b2 MIME-Version: 1.0 To: Frederic Weisbecker , Ingo Molnar CC: Steven Rostedt , Tom Zanussi , LKML Subject: [PATCH v2] tracing/filters: Improve subsystem filter Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9507 Lines: 338 Currently a subsystem filter should be applicable to all events under the subsystem, and if it failed, all the event filters will be cleared. Those behaviors make subsys filter much less useful: # echo 'vec == 1' > irq/softirq_entry/filter # echo 'irq == 5' > irq/filter bash: echo: write error: Invalid argument # cat irq/softirq_entry/filter none I'd expect it set the filter for irq_handler_entry/exit, and not touch softirq_entry/exit. The basic idea is, try to see if the filter can be applied to which events, and then just apply to the those events: # echo 'vec == 1' > softirq_entry/filter # echo 'irq == 5' > filter # cat irq_handler_entry/filter irq == 5 # cat softirq_entry/filter vec == 1 Changelog for v2: - do some cleanups to address Frederic's comments. Inspied-by: Steven Rostedt Signed-off-by: Li Zefan --- include/linux/ftrace_event.h | 4 +- kernel/trace/trace.h | 3 +- kernel/trace/trace_events_filter.c | 124 ++++++++++++++++++++++++------------ 3 files changed, 87 insertions(+), 44 deletions(-) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 5c093ff..26d3673 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -101,6 +101,8 @@ void trace_current_buffer_discard_commit(struct ring_buffer_event *event); void tracing_record_cmdline(struct task_struct *tsk); +struct event_filter; + struct ftrace_event_call { struct list_head list; char *name; @@ -116,7 +118,7 @@ struct ftrace_event_call { int (*define_fields)(void); struct list_head fields; int filter_active; - void *filter; + struct event_filter *filter; void *mod; #ifdef CONFIG_EVENT_PROFILE diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 06886a0..3a87d46 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -768,13 +768,14 @@ struct event_filter { int n_preds; struct filter_pred **preds; char *filter_string; + bool no_reset; }; struct event_subsystem { struct list_head list; const char *name; struct dentry *entry; - void *filter; + struct event_filter *filter; int nr_events; }; diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index b9aae72..c7ed427 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -418,7 +418,14 @@ oom: } EXPORT_SYMBOL_GPL(init_preds); -static void filter_free_subsystem_preds(struct event_subsystem *system) +enum { + FILTER_DISABLE_ALL, + FILTER_INIT_NO_RESET, + FILTER_SKIP_NO_RESET, +}; + +static void filter_free_subsystem_preds(struct event_subsystem *system, + int flag) { struct ftrace_event_call *call; @@ -426,6 +433,14 @@ static void filter_free_subsystem_preds(struct event_subsystem *system) if (!call->define_fields) continue; + if (flag == FILTER_INIT_NO_RESET) { + call->filter->no_reset = false; + continue; + } + + if (flag == FILTER_SKIP_NO_RESET && call->filter->no_reset) + continue; + if (!strcmp(call->system, system->name)) { filter_disable_preds(call); remove_filter_string(call->filter); @@ -527,7 +542,8 @@ static filter_pred_fn_t select_comparison_fn(int op, int field_size, static int filter_add_pred(struct filter_parse_state *ps, struct ftrace_event_call *call, - struct filter_pred *pred) + struct filter_pred *pred, + bool dry_run) { struct ftrace_event_field *field; filter_pred_fn_t fn; @@ -539,10 +555,12 @@ static int filter_add_pred(struct filter_parse_state *ps, if (pred->op == OP_AND) { pred->pop_n = 2; - return filter_add_pred_fn(ps, call, pred, filter_pred_and); + fn = filter_pred_and; + goto add_pred_fn; } else if (pred->op == OP_OR) { pred->pop_n = 2; - return filter_add_pred_fn(ps, call, pred, filter_pred_or); + fn = filter_pred_or; + goto add_pred_fn; } field = find_event_field(call, pred->field_name); @@ -565,9 +583,6 @@ static int filter_add_pred(struct filter_parse_state *ps, else fn = filter_pred_strloc; pred->str_len = field->size; - if (pred->op == OP_NE) - pred->not = 1; - return filter_add_pred_fn(ps, call, pred, fn); } else { if (field->is_signed) ret = strict_strtoll(pred->str_val, 0, &val); @@ -578,27 +593,33 @@ static int filter_add_pred(struct filter_parse_state *ps, return -EINVAL; } pred->val = val; - } - fn = select_comparison_fn(pred->op, field->size, field->is_signed); - if (!fn) { - parse_error(ps, FILT_ERR_INVALID_OP, 0); - return -EINVAL; + fn = select_comparison_fn(pred->op, field->size, + field->is_signed); + if (!fn) { + parse_error(ps, FILT_ERR_INVALID_OP, 0); + return -EINVAL; + } } if (pred->op == OP_NE) pred->not = 1; - return filter_add_pred_fn(ps, call, pred, fn); +add_pred_fn: + if (!dry_run) + return filter_add_pred_fn(ps, call, pred, fn); + return 0; } static int filter_add_subsystem_pred(struct filter_parse_state *ps, struct event_subsystem *system, struct filter_pred *pred, - char *filter_string) + char *filter_string, + bool dry_run) { struct ftrace_event_call *call; int err = 0; + bool fail = true; list_for_each_entry(call, &ftrace_events, list) { @@ -608,16 +629,24 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps, if (strcmp(call->system, system->name)) continue; - err = filter_add_pred(ps, call, pred); - if (err) { - filter_free_subsystem_preds(system); - parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); - goto out; - } - replace_filter_string(call->filter, filter_string); + if (call->filter->no_reset) + continue; + + err = filter_add_pred(ps, call, pred, dry_run); + if (err) + call->filter->no_reset = true; + else + fail = false; + + if (!dry_run) + replace_filter_string(call->filter, filter_string); } -out: - return err; + + if (fail) { + parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); + return err; + } + return 0; } static void parse_init(struct filter_parse_state *ps, @@ -976,12 +1005,14 @@ static int check_preds(struct filter_parse_state *ps) static int replace_preds(struct event_subsystem *system, struct ftrace_event_call *call, struct filter_parse_state *ps, - char *filter_string) + char *filter_string, + bool dry_run) { char *operand1 = NULL, *operand2 = NULL; struct filter_pred *pred; struct postfix_elt *elt; int err; + int n_preds = 0; err = check_preds(ps); if (err) @@ -1000,19 +1031,14 @@ static int replace_preds(struct event_subsystem *system, continue; } + if (n_preds++ == MAX_FILTER_PRED) { + parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); + return -ENOSPC; + } + if (elt->op == OP_AND || elt->op == OP_OR) { pred = create_logical_pred(elt->op); - if (call) - err = filter_add_pred(ps, call, pred); - else - err = filter_add_subsystem_pred(ps, system, - pred, filter_string); - filter_free_pred(pred); - if (err) - return err; - - operand1 = operand2 = NULL; - continue; + goto add_pred; } if (!operand1 || !operand2) { @@ -1021,11 +1047,12 @@ static int replace_preds(struct event_subsystem *system, } pred = create_pred(elt->op, operand1, operand2); +add_pred: if (call) - err = filter_add_pred(ps, call, pred); + err = filter_add_pred(ps, call, pred, false); else err = filter_add_subsystem_pred(ps, system, pred, - filter_string); + filter_string, dry_run); filter_free_pred(pred); if (err) return err; @@ -1066,7 +1093,7 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string) goto out; } - err = replace_preds(NULL, call, ps, filter_string); + err = replace_preds(NULL, call, ps, filter_string, false); if (err) append_filter_err(ps, call->filter); @@ -1090,7 +1117,7 @@ int apply_subsystem_event_filter(struct event_subsystem *system, mutex_lock(&event_mutex); if (!strcmp(strstrip(filter_string), "0")) { - filter_free_subsystem_preds(system); + filter_free_subsystem_preds(system, FILTER_DISABLE_ALL); remove_filter_string(system->filter); mutex_unlock(&event_mutex); return 0; @@ -1101,7 +1128,6 @@ int apply_subsystem_event_filter(struct event_subsystem *system, if (!ps) goto out_unlock; - filter_free_subsystem_preds(system); replace_filter_string(system->filter, filter_string); parse_init(ps, filter_ops, filter_string); @@ -1111,9 +1137,23 @@ int apply_subsystem_event_filter(struct event_subsystem *system, goto out; } - err = replace_preds(system, NULL, ps, filter_string); - if (err) + filter_free_subsystem_preds(system, FILTER_INIT_NO_RESET); + + /* try to see the filter can be applied to which events */ + err = replace_preds(system, NULL, ps, filter_string, true); + if (err) { + append_filter_err(ps, system->filter); + goto out; + } + + filter_free_subsystem_preds(system, FILTER_SKIP_NO_RESET); + + /* really apply the filter to the events */ + err = replace_preds(system, NULL, ps, filter_string, false); + if (err) { append_filter_err(ps, system->filter); + filter_free_subsystem_preds(system, 2); + } out: filter_opstack_clear(ps); -- 1.6.3 -- 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/