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![Steven Rostedt (Red Hat)](/assets/img/avatar_default.png)
As trace event triggers are now part of the mainline kernel, I added my trace event trigger tests to my test suite I run on all my kernels. Now these tests get run under different config options, and one of those options is CONFIG_PROVE_RCU, which checks under lockdep that the rcu locking primitives are being used correctly. This triggered the following splat: =============================== [ INFO: suspicious RCU usage. ] 3.15.0-rc2-test+ #11 Not tainted ------------------------------- kernel/trace/trace_events_trigger.c:80 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by swapper/1/0: #0: ((&(&j_cdbs->work)->timer)){..-...}, at: [<ffffffff8104d2cc>] call_timer_fn+0x5/0x1be #1: (&(&pool->lock)->rlock){-.-...}, at: [<ffffffff81059856>] __queue_work+0x140/0x283 #2: (&p->pi_lock){-.-.-.}, at: [<ffffffff8106e961>] try_to_wake_up+0x2e/0x1e8 #3: (&rq->lock){-.-.-.}, at: [<ffffffff8106ead3>] try_to_wake_up+0x1a0/0x1e8 stack backtrace: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.15.0-rc2-test+ #11 Hardware name: /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006 0000000000000001 ffff88007e083b98 ffffffff819f53a5 0000000000000006 ffff88007b0942c0 ffff88007e083bc8 ffffffff81081307 ffff88007ad96d20 0000000000000000 ffff88007af2d840 ffff88007b2e701c ffff88007e083c18 Call Trace: <IRQ> [<ffffffff819f53a5>] dump_stack+0x4f/0x7c [<ffffffff81081307>] lockdep_rcu_suspicious+0x107/0x110 [<ffffffff810ee51c>] event_triggers_call+0x99/0x108 [<ffffffff810e8174>] ftrace_event_buffer_commit+0x42/0xa4 [<ffffffff8106aadc>] ftrace_raw_event_sched_wakeup_template+0x71/0x7c [<ffffffff8106bcbf>] ttwu_do_wakeup+0x7f/0xff [<ffffffff8106bd9b>] ttwu_do_activate.constprop.126+0x5c/0x61 [<ffffffff8106eadf>] try_to_wake_up+0x1ac/0x1e8 [<ffffffff8106eb77>] wake_up_process+0x36/0x3b [<ffffffff810575cc>] wake_up_worker+0x24/0x26 [<ffffffff810578bc>] insert_work+0x5c/0x65 [<ffffffff81059982>] __queue_work+0x26c/0x283 [<ffffffff81059999>] ? __queue_work+0x283/0x283 [<ffffffff810599b7>] delayed_work_timer_fn+0x1e/0x20 [<ffffffff8104d3a6>] call_timer_fn+0xdf/0x1be^M [<ffffffff8104d2cc>] ? call_timer_fn+0x5/0x1be [<ffffffff81059999>] ? __queue_work+0x283/0x283 [<ffffffff8104d823>] run_timer_softirq+0x1a4/0x22f^M [<ffffffff8104696d>] __do_softirq+0x17b/0x31b^M [<ffffffff81046d03>] irq_exit+0x42/0x97 [<ffffffff81a08db6>] smp_apic_timer_interrupt+0x37/0x44 [<ffffffff81a07a2f>] apic_timer_interrupt+0x6f/0x80 <EOI> [<ffffffff8100a5d8>] ? default_idle+0x21/0x32 [<ffffffff8100a5d6>] ? default_idle+0x1f/0x32 [<ffffffff8100ac10>] arch_cpu_idle+0xf/0x11 [<ffffffff8107b3a4>] cpu_startup_entry+0x1a3/0x213 [<ffffffff8102a23c>] start_secondary+0x212/0x219 The cause is that the triggers are protected by rcu_read_lock_sched() but the data is dereferenced with rcu_dereference() which expects it to be protected with rcu_read_lock(). The proper reference should be rcu_dereference_sched(). Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
1437 lines
35 KiB
C
1437 lines
35 KiB
C
/*
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* trace_events_trigger - trace event triggers
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*
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* Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com>
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*/
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#include <linux/module.h>
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#include <linux/ctype.h>
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#include <linux/mutex.h>
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#include <linux/slab.h>
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#include "trace.h"
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static LIST_HEAD(trigger_commands);
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static DEFINE_MUTEX(trigger_cmd_mutex);
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static void
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trigger_data_free(struct event_trigger_data *data)
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{
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if (data->cmd_ops->set_filter)
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data->cmd_ops->set_filter(NULL, data, NULL);
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synchronize_sched(); /* make sure current triggers exit before free */
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kfree(data);
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}
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/**
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* event_triggers_call - Call triggers associated with a trace event
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* @file: The ftrace_event_file associated with the event
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* @rec: The trace entry for the event, NULL for unconditional invocation
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*
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* For each trigger associated with an event, invoke the trigger
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* function registered with the associated trigger command. If rec is
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* non-NULL, it means that the trigger requires further processing and
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* shouldn't be unconditionally invoked. If rec is non-NULL and the
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* trigger has a filter associated with it, rec will checked against
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* the filter and if the record matches the trigger will be invoked.
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* If the trigger is a 'post_trigger', meaning it shouldn't be invoked
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* in any case until the current event is written, the trigger
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* function isn't invoked but the bit associated with the deferred
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* trigger is set in the return value.
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*
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* Returns an enum event_trigger_type value containing a set bit for
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* any trigger that should be deferred, ETT_NONE if nothing to defer.
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*
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* Called from tracepoint handlers (with rcu_read_lock_sched() held).
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*
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* Return: an enum event_trigger_type value containing a set bit for
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* any trigger that should be deferred, ETT_NONE if nothing to defer.
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*/
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enum event_trigger_type
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event_triggers_call(struct ftrace_event_file *file, void *rec)
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{
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struct event_trigger_data *data;
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enum event_trigger_type tt = ETT_NONE;
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struct event_filter *filter;
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if (list_empty(&file->triggers))
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return tt;
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list_for_each_entry_rcu(data, &file->triggers, list) {
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if (!rec) {
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data->ops->func(data);
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continue;
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}
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filter = rcu_dereference_sched(data->filter);
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if (filter && !filter_match_preds(filter, rec))
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continue;
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if (data->cmd_ops->post_trigger) {
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tt |= data->cmd_ops->trigger_type;
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continue;
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}
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data->ops->func(data);
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}
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return tt;
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}
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EXPORT_SYMBOL_GPL(event_triggers_call);
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/**
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* event_triggers_post_call - Call 'post_triggers' for a trace event
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* @file: The ftrace_event_file associated with the event
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* @tt: enum event_trigger_type containing a set bit for each trigger to invoke
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*
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* For each trigger associated with an event, invoke the trigger
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* function registered with the associated trigger command, if the
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* corresponding bit is set in the tt enum passed into this function.
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* See @event_triggers_call for details on how those bits are set.
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*
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* Called from tracepoint handlers (with rcu_read_lock_sched() held).
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*/
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void
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event_triggers_post_call(struct ftrace_event_file *file,
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enum event_trigger_type tt)
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{
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struct event_trigger_data *data;
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list_for_each_entry_rcu(data, &file->triggers, list) {
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if (data->cmd_ops->trigger_type & tt)
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data->ops->func(data);
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}
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}
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EXPORT_SYMBOL_GPL(event_triggers_post_call);
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#define SHOW_AVAILABLE_TRIGGERS (void *)(1UL)
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static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
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{
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struct ftrace_event_file *event_file = event_file_data(m->private);
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if (t == SHOW_AVAILABLE_TRIGGERS)
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return NULL;
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return seq_list_next(t, &event_file->triggers, pos);
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}
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static void *trigger_start(struct seq_file *m, loff_t *pos)
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{
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struct ftrace_event_file *event_file;
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/* ->stop() is called even if ->start() fails */
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mutex_lock(&event_mutex);
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event_file = event_file_data(m->private);
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if (unlikely(!event_file))
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return ERR_PTR(-ENODEV);
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if (list_empty(&event_file->triggers))
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return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL;
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return seq_list_start(&event_file->triggers, *pos);
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}
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static void trigger_stop(struct seq_file *m, void *t)
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{
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mutex_unlock(&event_mutex);
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}
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static int trigger_show(struct seq_file *m, void *v)
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{
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struct event_trigger_data *data;
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struct event_command *p;
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if (v == SHOW_AVAILABLE_TRIGGERS) {
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seq_puts(m, "# Available triggers:\n");
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seq_putc(m, '#');
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mutex_lock(&trigger_cmd_mutex);
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list_for_each_entry_reverse(p, &trigger_commands, list)
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seq_printf(m, " %s", p->name);
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seq_putc(m, '\n');
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mutex_unlock(&trigger_cmd_mutex);
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return 0;
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}
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data = list_entry(v, struct event_trigger_data, list);
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data->ops->print(m, data->ops, data);
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return 0;
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}
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static const struct seq_operations event_triggers_seq_ops = {
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.start = trigger_start,
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.next = trigger_next,
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.stop = trigger_stop,
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.show = trigger_show,
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};
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static int event_trigger_regex_open(struct inode *inode, struct file *file)
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{
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int ret = 0;
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mutex_lock(&event_mutex);
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if (unlikely(!event_file_data(file))) {
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mutex_unlock(&event_mutex);
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return -ENODEV;
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}
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if (file->f_mode & FMODE_READ) {
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ret = seq_open(file, &event_triggers_seq_ops);
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if (!ret) {
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struct seq_file *m = file->private_data;
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m->private = file;
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}
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}
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mutex_unlock(&event_mutex);
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return ret;
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}
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static int trigger_process_regex(struct ftrace_event_file *file, char *buff)
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{
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char *command, *next = buff;
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struct event_command *p;
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int ret = -EINVAL;
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command = strsep(&next, ": \t");
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command = (command[0] != '!') ? command : command + 1;
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mutex_lock(&trigger_cmd_mutex);
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list_for_each_entry(p, &trigger_commands, list) {
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if (strcmp(p->name, command) == 0) {
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ret = p->func(p, file, buff, command, next);
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goto out_unlock;
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}
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}
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out_unlock:
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mutex_unlock(&trigger_cmd_mutex);
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return ret;
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}
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static ssize_t event_trigger_regex_write(struct file *file,
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const char __user *ubuf,
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size_t cnt, loff_t *ppos)
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{
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struct ftrace_event_file *event_file;
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ssize_t ret;
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char *buf;
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if (!cnt)
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return 0;
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if (cnt >= PAGE_SIZE)
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return -EINVAL;
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buf = (char *)__get_free_page(GFP_TEMPORARY);
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if (!buf)
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return -ENOMEM;
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if (copy_from_user(buf, ubuf, cnt)) {
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free_page((unsigned long)buf);
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return -EFAULT;
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}
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buf[cnt] = '\0';
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strim(buf);
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mutex_lock(&event_mutex);
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event_file = event_file_data(file);
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if (unlikely(!event_file)) {
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mutex_unlock(&event_mutex);
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free_page((unsigned long)buf);
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return -ENODEV;
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}
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ret = trigger_process_regex(event_file, buf);
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mutex_unlock(&event_mutex);
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free_page((unsigned long)buf);
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if (ret < 0)
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goto out;
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*ppos += cnt;
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ret = cnt;
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out:
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return ret;
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}
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static int event_trigger_regex_release(struct inode *inode, struct file *file)
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{
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mutex_lock(&event_mutex);
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if (file->f_mode & FMODE_READ)
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seq_release(inode, file);
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mutex_unlock(&event_mutex);
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return 0;
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}
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static ssize_t
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event_trigger_write(struct file *filp, const char __user *ubuf,
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size_t cnt, loff_t *ppos)
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{
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return event_trigger_regex_write(filp, ubuf, cnt, ppos);
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}
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static int
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event_trigger_open(struct inode *inode, struct file *filp)
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{
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return event_trigger_regex_open(inode, filp);
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}
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static int
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event_trigger_release(struct inode *inode, struct file *file)
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{
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return event_trigger_regex_release(inode, file);
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}
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const struct file_operations event_trigger_fops = {
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.open = event_trigger_open,
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.read = seq_read,
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.write = event_trigger_write,
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.llseek = tracing_lseek,
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.release = event_trigger_release,
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};
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/*
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* Currently we only register event commands from __init, so mark this
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* __init too.
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*/
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static __init int register_event_command(struct event_command *cmd)
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{
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struct event_command *p;
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int ret = 0;
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mutex_lock(&trigger_cmd_mutex);
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list_for_each_entry(p, &trigger_commands, list) {
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if (strcmp(cmd->name, p->name) == 0) {
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ret = -EBUSY;
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goto out_unlock;
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}
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}
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list_add(&cmd->list, &trigger_commands);
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out_unlock:
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mutex_unlock(&trigger_cmd_mutex);
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return ret;
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}
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/*
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* Currently we only unregister event commands from __init, so mark
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* this __init too.
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*/
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static __init int unregister_event_command(struct event_command *cmd)
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{
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struct event_command *p, *n;
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int ret = -ENODEV;
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mutex_lock(&trigger_cmd_mutex);
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list_for_each_entry_safe(p, n, &trigger_commands, list) {
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if (strcmp(cmd->name, p->name) == 0) {
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ret = 0;
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list_del_init(&p->list);
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goto out_unlock;
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}
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}
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out_unlock:
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mutex_unlock(&trigger_cmd_mutex);
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return ret;
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}
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/**
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* event_trigger_print - Generic event_trigger_ops @print implementation
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* @name: The name of the event trigger
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* @m: The seq_file being printed to
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* @data: Trigger-specific data
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* @filter_str: filter_str to print, if present
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*
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* Common implementation for event triggers to print themselves.
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*
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* Usually wrapped by a function that simply sets the @name of the
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* trigger command and then invokes this.
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*
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* Return: 0 on success, errno otherwise
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*/
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static int
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event_trigger_print(const char *name, struct seq_file *m,
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void *data, char *filter_str)
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{
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long count = (long)data;
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seq_printf(m, "%s", name);
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if (count == -1)
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seq_puts(m, ":unlimited");
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else
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seq_printf(m, ":count=%ld", count);
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if (filter_str)
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seq_printf(m, " if %s\n", filter_str);
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else
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seq_puts(m, "\n");
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return 0;
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}
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/**
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* event_trigger_init - Generic event_trigger_ops @init implementation
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* @ops: The trigger ops associated with the trigger
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* @data: Trigger-specific data
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*
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* Common implementation of event trigger initialization.
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*
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* Usually used directly as the @init method in event trigger
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* implementations.
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*
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* Return: 0 on success, errno otherwise
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*/
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static int
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event_trigger_init(struct event_trigger_ops *ops,
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struct event_trigger_data *data)
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{
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data->ref++;
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return 0;
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}
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/**
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* event_trigger_free - Generic event_trigger_ops @free implementation
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* @ops: The trigger ops associated with the trigger
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* @data: Trigger-specific data
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*
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* Common implementation of event trigger de-initialization.
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*
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* Usually used directly as the @free method in event trigger
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* implementations.
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*/
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static void
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event_trigger_free(struct event_trigger_ops *ops,
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struct event_trigger_data *data)
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{
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if (WARN_ON_ONCE(data->ref <= 0))
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return;
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data->ref--;
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if (!data->ref)
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trigger_data_free(data);
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}
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static int trace_event_trigger_enable_disable(struct ftrace_event_file *file,
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int trigger_enable)
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{
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int ret = 0;
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if (trigger_enable) {
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if (atomic_inc_return(&file->tm_ref) > 1)
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return ret;
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set_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags);
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ret = trace_event_enable_disable(file, 1, 1);
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} else {
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if (atomic_dec_return(&file->tm_ref) > 0)
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return ret;
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clear_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags);
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ret = trace_event_enable_disable(file, 0, 1);
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}
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return ret;
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}
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/**
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* clear_event_triggers - Clear all triggers associated with a trace array
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* @tr: The trace array to clear
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*
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* For each trigger, the triggering event has its tm_ref decremented
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* via trace_event_trigger_enable_disable(), and any associated event
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* (in the case of enable/disable_event triggers) will have its sm_ref
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|
* decremented via free()->trace_event_enable_disable(). That
|
|
* combination effectively reverses the soft-mode/trigger state added
|
|
* by trigger registration.
|
|
*
|
|
* Must be called with event_mutex held.
|
|
*/
|
|
void
|
|
clear_event_triggers(struct trace_array *tr)
|
|
{
|
|
struct ftrace_event_file *file;
|
|
|
|
list_for_each_entry(file, &tr->events, list) {
|
|
struct event_trigger_data *data;
|
|
list_for_each_entry_rcu(data, &file->triggers, list) {
|
|
trace_event_trigger_enable_disable(file, 0);
|
|
if (data->ops->free)
|
|
data->ops->free(data->ops, data);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* update_cond_flag - Set or reset the TRIGGER_COND bit
|
|
* @file: The ftrace_event_file associated with the event
|
|
*
|
|
* If an event has triggers and any of those triggers has a filter or
|
|
* a post_trigger, trigger invocation needs to be deferred until after
|
|
* the current event has logged its data, and the event should have
|
|
* its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be
|
|
* cleared.
|
|
*/
|
|
static void update_cond_flag(struct ftrace_event_file *file)
|
|
{
|
|
struct event_trigger_data *data;
|
|
bool set_cond = false;
|
|
|
|
list_for_each_entry_rcu(data, &file->triggers, list) {
|
|
if (data->filter || data->cmd_ops->post_trigger) {
|
|
set_cond = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (set_cond)
|
|
set_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags);
|
|
else
|
|
clear_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags);
|
|
}
|
|
|
|
/**
|
|
* register_trigger - Generic event_command @reg implementation
|
|
* @glob: The raw string used to register the trigger
|
|
* @ops: The trigger ops associated with the trigger
|
|
* @data: Trigger-specific data to associate with the trigger
|
|
* @file: The ftrace_event_file associated with the event
|
|
*
|
|
* Common implementation for event trigger registration.
|
|
*
|
|
* Usually used directly as the @reg method in event command
|
|
* implementations.
|
|
*
|
|
* Return: 0 on success, errno otherwise
|
|
*/
|
|
static int register_trigger(char *glob, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data,
|
|
struct ftrace_event_file *file)
|
|
{
|
|
struct event_trigger_data *test;
|
|
int ret = 0;
|
|
|
|
list_for_each_entry_rcu(test, &file->triggers, list) {
|
|
if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) {
|
|
ret = -EEXIST;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (data->ops->init) {
|
|
ret = data->ops->init(data->ops, data);
|
|
if (ret < 0)
|
|
goto out;
|
|
}
|
|
|
|
list_add_rcu(&data->list, &file->triggers);
|
|
ret++;
|
|
|
|
if (trace_event_trigger_enable_disable(file, 1) < 0) {
|
|
list_del_rcu(&data->list);
|
|
ret--;
|
|
}
|
|
update_cond_flag(file);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* unregister_trigger - Generic event_command @unreg implementation
|
|
* @glob: The raw string used to register the trigger
|
|
* @ops: The trigger ops associated with the trigger
|
|
* @test: Trigger-specific data used to find the trigger to remove
|
|
* @file: The ftrace_event_file associated with the event
|
|
*
|
|
* Common implementation for event trigger unregistration.
|
|
*
|
|
* Usually used directly as the @unreg method in event command
|
|
* implementations.
|
|
*/
|
|
static void unregister_trigger(char *glob, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *test,
|
|
struct ftrace_event_file *file)
|
|
{
|
|
struct event_trigger_data *data;
|
|
bool unregistered = false;
|
|
|
|
list_for_each_entry_rcu(data, &file->triggers, list) {
|
|
if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) {
|
|
unregistered = true;
|
|
list_del_rcu(&data->list);
|
|
update_cond_flag(file);
|
|
trace_event_trigger_enable_disable(file, 0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (unregistered && data->ops->free)
|
|
data->ops->free(data->ops, data);
|
|
}
|
|
|
|
/**
|
|
* event_trigger_callback - Generic event_command @func implementation
|
|
* @cmd_ops: The command ops, used for trigger registration
|
|
* @file: The ftrace_event_file associated with the event
|
|
* @glob: The raw string used to register the trigger
|
|
* @cmd: The cmd portion of the string used to register the trigger
|
|
* @param: The params portion of the string used to register the trigger
|
|
*
|
|
* Common implementation for event command parsing and trigger
|
|
* instantiation.
|
|
*
|
|
* Usually used directly as the @func method in event command
|
|
* implementations.
|
|
*
|
|
* Return: 0 on success, errno otherwise
|
|
*/
|
|
static int
|
|
event_trigger_callback(struct event_command *cmd_ops,
|
|
struct ftrace_event_file *file,
|
|
char *glob, char *cmd, char *param)
|
|
{
|
|
struct event_trigger_data *trigger_data;
|
|
struct event_trigger_ops *trigger_ops;
|
|
char *trigger = NULL;
|
|
char *number;
|
|
int ret;
|
|
|
|
/* separate the trigger from the filter (t:n [if filter]) */
|
|
if (param && isdigit(param[0]))
|
|
trigger = strsep(¶m, " \t");
|
|
|
|
trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
|
|
|
|
ret = -ENOMEM;
|
|
trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
|
|
if (!trigger_data)
|
|
goto out;
|
|
|
|
trigger_data->count = -1;
|
|
trigger_data->ops = trigger_ops;
|
|
trigger_data->cmd_ops = cmd_ops;
|
|
INIT_LIST_HEAD(&trigger_data->list);
|
|
|
|
if (glob[0] == '!') {
|
|
cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
|
|
kfree(trigger_data);
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
if (trigger) {
|
|
number = strsep(&trigger, ":");
|
|
|
|
ret = -EINVAL;
|
|
if (!strlen(number))
|
|
goto out_free;
|
|
|
|
/*
|
|
* We use the callback data field (which is a pointer)
|
|
* as our counter.
|
|
*/
|
|
ret = kstrtoul(number, 0, &trigger_data->count);
|
|
if (ret)
|
|
goto out_free;
|
|
}
|
|
|
|
if (!param) /* if param is non-empty, it's supposed to be a filter */
|
|
goto out_reg;
|
|
|
|
if (!cmd_ops->set_filter)
|
|
goto out_reg;
|
|
|
|
ret = cmd_ops->set_filter(param, trigger_data, file);
|
|
if (ret < 0)
|
|
goto out_free;
|
|
|
|
out_reg:
|
|
ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
|
|
/*
|
|
* The above returns on success the # of functions enabled,
|
|
* but if it didn't find any functions it returns zero.
|
|
* Consider no functions a failure too.
|
|
*/
|
|
if (!ret) {
|
|
ret = -ENOENT;
|
|
goto out_free;
|
|
} else if (ret < 0)
|
|
goto out_free;
|
|
ret = 0;
|
|
out:
|
|
return ret;
|
|
|
|
out_free:
|
|
if (cmd_ops->set_filter)
|
|
cmd_ops->set_filter(NULL, trigger_data, NULL);
|
|
kfree(trigger_data);
|
|
goto out;
|
|
}
|
|
|
|
/**
|
|
* set_trigger_filter - Generic event_command @set_filter implementation
|
|
* @filter_str: The filter string for the trigger, NULL to remove filter
|
|
* @trigger_data: Trigger-specific data
|
|
* @file: The ftrace_event_file associated with the event
|
|
*
|
|
* Common implementation for event command filter parsing and filter
|
|
* instantiation.
|
|
*
|
|
* Usually used directly as the @set_filter method in event command
|
|
* implementations.
|
|
*
|
|
* Also used to remove a filter (if filter_str = NULL).
|
|
*
|
|
* Return: 0 on success, errno otherwise
|
|
*/
|
|
static int set_trigger_filter(char *filter_str,
|
|
struct event_trigger_data *trigger_data,
|
|
struct ftrace_event_file *file)
|
|
{
|
|
struct event_trigger_data *data = trigger_data;
|
|
struct event_filter *filter = NULL, *tmp;
|
|
int ret = -EINVAL;
|
|
char *s;
|
|
|
|
if (!filter_str) /* clear the current filter */
|
|
goto assign;
|
|
|
|
s = strsep(&filter_str, " \t");
|
|
|
|
if (!strlen(s) || strcmp(s, "if") != 0)
|
|
goto out;
|
|
|
|
if (!filter_str)
|
|
goto out;
|
|
|
|
/* The filter is for the 'trigger' event, not the triggered event */
|
|
ret = create_event_filter(file->event_call, filter_str, false, &filter);
|
|
if (ret)
|
|
goto out;
|
|
assign:
|
|
tmp = rcu_access_pointer(data->filter);
|
|
|
|
rcu_assign_pointer(data->filter, filter);
|
|
|
|
if (tmp) {
|
|
/* Make sure the call is done with the filter */
|
|
synchronize_sched();
|
|
free_event_filter(tmp);
|
|
}
|
|
|
|
kfree(data->filter_str);
|
|
data->filter_str = NULL;
|
|
|
|
if (filter_str) {
|
|
data->filter_str = kstrdup(filter_str, GFP_KERNEL);
|
|
if (!data->filter_str) {
|
|
free_event_filter(rcu_access_pointer(data->filter));
|
|
data->filter = NULL;
|
|
ret = -ENOMEM;
|
|
}
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static void
|
|
traceon_trigger(struct event_trigger_data *data)
|
|
{
|
|
if (tracing_is_on())
|
|
return;
|
|
|
|
tracing_on();
|
|
}
|
|
|
|
static void
|
|
traceon_count_trigger(struct event_trigger_data *data)
|
|
{
|
|
if (tracing_is_on())
|
|
return;
|
|
|
|
if (!data->count)
|
|
return;
|
|
|
|
if (data->count != -1)
|
|
(data->count)--;
|
|
|
|
tracing_on();
|
|
}
|
|
|
|
static void
|
|
traceoff_trigger(struct event_trigger_data *data)
|
|
{
|
|
if (!tracing_is_on())
|
|
return;
|
|
|
|
tracing_off();
|
|
}
|
|
|
|
static void
|
|
traceoff_count_trigger(struct event_trigger_data *data)
|
|
{
|
|
if (!tracing_is_on())
|
|
return;
|
|
|
|
if (!data->count)
|
|
return;
|
|
|
|
if (data->count != -1)
|
|
(data->count)--;
|
|
|
|
tracing_off();
|
|
}
|
|
|
|
static int
|
|
traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data)
|
|
{
|
|
return event_trigger_print("traceon", m, (void *)data->count,
|
|
data->filter_str);
|
|
}
|
|
|
|
static int
|
|
traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data)
|
|
{
|
|
return event_trigger_print("traceoff", m, (void *)data->count,
|
|
data->filter_str);
|
|
}
|
|
|
|
static struct event_trigger_ops traceon_trigger_ops = {
|
|
.func = traceon_trigger,
|
|
.print = traceon_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops traceon_count_trigger_ops = {
|
|
.func = traceon_count_trigger,
|
|
.print = traceon_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops traceoff_trigger_ops = {
|
|
.func = traceoff_trigger,
|
|
.print = traceoff_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops traceoff_count_trigger_ops = {
|
|
.func = traceoff_count_trigger,
|
|
.print = traceoff_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops *
|
|
onoff_get_trigger_ops(char *cmd, char *param)
|
|
{
|
|
struct event_trigger_ops *ops;
|
|
|
|
/* we register both traceon and traceoff to this callback */
|
|
if (strcmp(cmd, "traceon") == 0)
|
|
ops = param ? &traceon_count_trigger_ops :
|
|
&traceon_trigger_ops;
|
|
else
|
|
ops = param ? &traceoff_count_trigger_ops :
|
|
&traceoff_trigger_ops;
|
|
|
|
return ops;
|
|
}
|
|
|
|
static struct event_command trigger_traceon_cmd = {
|
|
.name = "traceon",
|
|
.trigger_type = ETT_TRACE_ONOFF,
|
|
.func = event_trigger_callback,
|
|
.reg = register_trigger,
|
|
.unreg = unregister_trigger,
|
|
.get_trigger_ops = onoff_get_trigger_ops,
|
|
.set_filter = set_trigger_filter,
|
|
};
|
|
|
|
static struct event_command trigger_traceoff_cmd = {
|
|
.name = "traceoff",
|
|
.trigger_type = ETT_TRACE_ONOFF,
|
|
.func = event_trigger_callback,
|
|
.reg = register_trigger,
|
|
.unreg = unregister_trigger,
|
|
.get_trigger_ops = onoff_get_trigger_ops,
|
|
.set_filter = set_trigger_filter,
|
|
};
|
|
|
|
#ifdef CONFIG_TRACER_SNAPSHOT
|
|
static void
|
|
snapshot_trigger(struct event_trigger_data *data)
|
|
{
|
|
tracing_snapshot();
|
|
}
|
|
|
|
static void
|
|
snapshot_count_trigger(struct event_trigger_data *data)
|
|
{
|
|
if (!data->count)
|
|
return;
|
|
|
|
if (data->count != -1)
|
|
(data->count)--;
|
|
|
|
snapshot_trigger(data);
|
|
}
|
|
|
|
static int
|
|
register_snapshot_trigger(char *glob, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data,
|
|
struct ftrace_event_file *file)
|
|
{
|
|
int ret = register_trigger(glob, ops, data, file);
|
|
|
|
if (ret > 0 && tracing_alloc_snapshot() != 0) {
|
|
unregister_trigger(glob, ops, data, file);
|
|
ret = 0;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data)
|
|
{
|
|
return event_trigger_print("snapshot", m, (void *)data->count,
|
|
data->filter_str);
|
|
}
|
|
|
|
static struct event_trigger_ops snapshot_trigger_ops = {
|
|
.func = snapshot_trigger,
|
|
.print = snapshot_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops snapshot_count_trigger_ops = {
|
|
.func = snapshot_count_trigger,
|
|
.print = snapshot_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops *
|
|
snapshot_get_trigger_ops(char *cmd, char *param)
|
|
{
|
|
return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops;
|
|
}
|
|
|
|
static struct event_command trigger_snapshot_cmd = {
|
|
.name = "snapshot",
|
|
.trigger_type = ETT_SNAPSHOT,
|
|
.func = event_trigger_callback,
|
|
.reg = register_snapshot_trigger,
|
|
.unreg = unregister_trigger,
|
|
.get_trigger_ops = snapshot_get_trigger_ops,
|
|
.set_filter = set_trigger_filter,
|
|
};
|
|
|
|
static __init int register_trigger_snapshot_cmd(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = register_event_command(&trigger_snapshot_cmd);
|
|
WARN_ON(ret < 0);
|
|
|
|
return ret;
|
|
}
|
|
#else
|
|
static __init int register_trigger_snapshot_cmd(void) { return 0; }
|
|
#endif /* CONFIG_TRACER_SNAPSHOT */
|
|
|
|
#ifdef CONFIG_STACKTRACE
|
|
/*
|
|
* Skip 3:
|
|
* stacktrace_trigger()
|
|
* event_triggers_post_call()
|
|
* ftrace_raw_event_xxx()
|
|
*/
|
|
#define STACK_SKIP 3
|
|
|
|
static void
|
|
stacktrace_trigger(struct event_trigger_data *data)
|
|
{
|
|
trace_dump_stack(STACK_SKIP);
|
|
}
|
|
|
|
static void
|
|
stacktrace_count_trigger(struct event_trigger_data *data)
|
|
{
|
|
if (!data->count)
|
|
return;
|
|
|
|
if (data->count != -1)
|
|
(data->count)--;
|
|
|
|
stacktrace_trigger(data);
|
|
}
|
|
|
|
static int
|
|
stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data)
|
|
{
|
|
return event_trigger_print("stacktrace", m, (void *)data->count,
|
|
data->filter_str);
|
|
}
|
|
|
|
static struct event_trigger_ops stacktrace_trigger_ops = {
|
|
.func = stacktrace_trigger,
|
|
.print = stacktrace_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops stacktrace_count_trigger_ops = {
|
|
.func = stacktrace_count_trigger,
|
|
.print = stacktrace_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops *
|
|
stacktrace_get_trigger_ops(char *cmd, char *param)
|
|
{
|
|
return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops;
|
|
}
|
|
|
|
static struct event_command trigger_stacktrace_cmd = {
|
|
.name = "stacktrace",
|
|
.trigger_type = ETT_STACKTRACE,
|
|
.post_trigger = true,
|
|
.func = event_trigger_callback,
|
|
.reg = register_trigger,
|
|
.unreg = unregister_trigger,
|
|
.get_trigger_ops = stacktrace_get_trigger_ops,
|
|
.set_filter = set_trigger_filter,
|
|
};
|
|
|
|
static __init int register_trigger_stacktrace_cmd(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = register_event_command(&trigger_stacktrace_cmd);
|
|
WARN_ON(ret < 0);
|
|
|
|
return ret;
|
|
}
|
|
#else
|
|
static __init int register_trigger_stacktrace_cmd(void) { return 0; }
|
|
#endif /* CONFIG_STACKTRACE */
|
|
|
|
static __init void unregister_trigger_traceon_traceoff_cmds(void)
|
|
{
|
|
unregister_event_command(&trigger_traceon_cmd);
|
|
unregister_event_command(&trigger_traceoff_cmd);
|
|
}
|
|
|
|
/* Avoid typos */
|
|
#define ENABLE_EVENT_STR "enable_event"
|
|
#define DISABLE_EVENT_STR "disable_event"
|
|
|
|
struct enable_trigger_data {
|
|
struct ftrace_event_file *file;
|
|
bool enable;
|
|
};
|
|
|
|
static void
|
|
event_enable_trigger(struct event_trigger_data *data)
|
|
{
|
|
struct enable_trigger_data *enable_data = data->private_data;
|
|
|
|
if (enable_data->enable)
|
|
clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags);
|
|
else
|
|
set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags);
|
|
}
|
|
|
|
static void
|
|
event_enable_count_trigger(struct event_trigger_data *data)
|
|
{
|
|
struct enable_trigger_data *enable_data = data->private_data;
|
|
|
|
if (!data->count)
|
|
return;
|
|
|
|
/* Skip if the event is in a state we want to switch to */
|
|
if (enable_data->enable == !(enable_data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED))
|
|
return;
|
|
|
|
if (data->count != -1)
|
|
(data->count)--;
|
|
|
|
event_enable_trigger(data);
|
|
}
|
|
|
|
static int
|
|
event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data)
|
|
{
|
|
struct enable_trigger_data *enable_data = data->private_data;
|
|
|
|
seq_printf(m, "%s:%s:%s",
|
|
enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
|
|
enable_data->file->event_call->class->system,
|
|
ftrace_event_name(enable_data->file->event_call));
|
|
|
|
if (data->count == -1)
|
|
seq_puts(m, ":unlimited");
|
|
else
|
|
seq_printf(m, ":count=%ld", data->count);
|
|
|
|
if (data->filter_str)
|
|
seq_printf(m, " if %s\n", data->filter_str);
|
|
else
|
|
seq_puts(m, "\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
event_enable_trigger_free(struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data)
|
|
{
|
|
struct enable_trigger_data *enable_data = data->private_data;
|
|
|
|
if (WARN_ON_ONCE(data->ref <= 0))
|
|
return;
|
|
|
|
data->ref--;
|
|
if (!data->ref) {
|
|
/* Remove the SOFT_MODE flag */
|
|
trace_event_enable_disable(enable_data->file, 0, 1);
|
|
module_put(enable_data->file->event_call->mod);
|
|
trigger_data_free(data);
|
|
kfree(enable_data);
|
|
}
|
|
}
|
|
|
|
static struct event_trigger_ops event_enable_trigger_ops = {
|
|
.func = event_enable_trigger,
|
|
.print = event_enable_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_enable_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops event_enable_count_trigger_ops = {
|
|
.func = event_enable_count_trigger,
|
|
.print = event_enable_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_enable_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops event_disable_trigger_ops = {
|
|
.func = event_enable_trigger,
|
|
.print = event_enable_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_enable_trigger_free,
|
|
};
|
|
|
|
static struct event_trigger_ops event_disable_count_trigger_ops = {
|
|
.func = event_enable_count_trigger,
|
|
.print = event_enable_trigger_print,
|
|
.init = event_trigger_init,
|
|
.free = event_enable_trigger_free,
|
|
};
|
|
|
|
static int
|
|
event_enable_trigger_func(struct event_command *cmd_ops,
|
|
struct ftrace_event_file *file,
|
|
char *glob, char *cmd, char *param)
|
|
{
|
|
struct ftrace_event_file *event_enable_file;
|
|
struct enable_trigger_data *enable_data;
|
|
struct event_trigger_data *trigger_data;
|
|
struct event_trigger_ops *trigger_ops;
|
|
struct trace_array *tr = file->tr;
|
|
const char *system;
|
|
const char *event;
|
|
char *trigger;
|
|
char *number;
|
|
bool enable;
|
|
int ret;
|
|
|
|
if (!param)
|
|
return -EINVAL;
|
|
|
|
/* separate the trigger from the filter (s:e:n [if filter]) */
|
|
trigger = strsep(¶m, " \t");
|
|
if (!trigger)
|
|
return -EINVAL;
|
|
|
|
system = strsep(&trigger, ":");
|
|
if (!trigger)
|
|
return -EINVAL;
|
|
|
|
event = strsep(&trigger, ":");
|
|
|
|
ret = -EINVAL;
|
|
event_enable_file = find_event_file(tr, system, event);
|
|
if (!event_enable_file)
|
|
goto out;
|
|
|
|
enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
|
|
|
|
trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
|
|
|
|
ret = -ENOMEM;
|
|
trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
|
|
if (!trigger_data)
|
|
goto out;
|
|
|
|
enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL);
|
|
if (!enable_data) {
|
|
kfree(trigger_data);
|
|
goto out;
|
|
}
|
|
|
|
trigger_data->count = -1;
|
|
trigger_data->ops = trigger_ops;
|
|
trigger_data->cmd_ops = cmd_ops;
|
|
INIT_LIST_HEAD(&trigger_data->list);
|
|
RCU_INIT_POINTER(trigger_data->filter, NULL);
|
|
|
|
enable_data->enable = enable;
|
|
enable_data->file = event_enable_file;
|
|
trigger_data->private_data = enable_data;
|
|
|
|
if (glob[0] == '!') {
|
|
cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
|
|
kfree(trigger_data);
|
|
kfree(enable_data);
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
if (trigger) {
|
|
number = strsep(&trigger, ":");
|
|
|
|
ret = -EINVAL;
|
|
if (!strlen(number))
|
|
goto out_free;
|
|
|
|
/*
|
|
* We use the callback data field (which is a pointer)
|
|
* as our counter.
|
|
*/
|
|
ret = kstrtoul(number, 0, &trigger_data->count);
|
|
if (ret)
|
|
goto out_free;
|
|
}
|
|
|
|
if (!param) /* if param is non-empty, it's supposed to be a filter */
|
|
goto out_reg;
|
|
|
|
if (!cmd_ops->set_filter)
|
|
goto out_reg;
|
|
|
|
ret = cmd_ops->set_filter(param, trigger_data, file);
|
|
if (ret < 0)
|
|
goto out_free;
|
|
|
|
out_reg:
|
|
/* Don't let event modules unload while probe registered */
|
|
ret = try_module_get(event_enable_file->event_call->mod);
|
|
if (!ret) {
|
|
ret = -EBUSY;
|
|
goto out_free;
|
|
}
|
|
|
|
ret = trace_event_enable_disable(event_enable_file, 1, 1);
|
|
if (ret < 0)
|
|
goto out_put;
|
|
ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
|
|
/*
|
|
* The above returns on success the # of functions enabled,
|
|
* but if it didn't find any functions it returns zero.
|
|
* Consider no functions a failure too.
|
|
*/
|
|
if (!ret) {
|
|
ret = -ENOENT;
|
|
goto out_disable;
|
|
} else if (ret < 0)
|
|
goto out_disable;
|
|
/* Just return zero, not the number of enabled functions */
|
|
ret = 0;
|
|
out:
|
|
return ret;
|
|
|
|
out_disable:
|
|
trace_event_enable_disable(event_enable_file, 0, 1);
|
|
out_put:
|
|
module_put(event_enable_file->event_call->mod);
|
|
out_free:
|
|
if (cmd_ops->set_filter)
|
|
cmd_ops->set_filter(NULL, trigger_data, NULL);
|
|
kfree(trigger_data);
|
|
kfree(enable_data);
|
|
goto out;
|
|
}
|
|
|
|
static int event_enable_register_trigger(char *glob,
|
|
struct event_trigger_ops *ops,
|
|
struct event_trigger_data *data,
|
|
struct ftrace_event_file *file)
|
|
{
|
|
struct enable_trigger_data *enable_data = data->private_data;
|
|
struct enable_trigger_data *test_enable_data;
|
|
struct event_trigger_data *test;
|
|
int ret = 0;
|
|
|
|
list_for_each_entry_rcu(test, &file->triggers, list) {
|
|
test_enable_data = test->private_data;
|
|
if (test_enable_data &&
|
|
(test_enable_data->file == enable_data->file)) {
|
|
ret = -EEXIST;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (data->ops->init) {
|
|
ret = data->ops->init(data->ops, data);
|
|
if (ret < 0)
|
|
goto out;
|
|
}
|
|
|
|
list_add_rcu(&data->list, &file->triggers);
|
|
ret++;
|
|
|
|
if (trace_event_trigger_enable_disable(file, 1) < 0) {
|
|
list_del_rcu(&data->list);
|
|
ret--;
|
|
}
|
|
update_cond_flag(file);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static void event_enable_unregister_trigger(char *glob,
|
|
struct event_trigger_ops *ops,
|
|
struct event_trigger_data *test,
|
|
struct ftrace_event_file *file)
|
|
{
|
|
struct enable_trigger_data *test_enable_data = test->private_data;
|
|
struct enable_trigger_data *enable_data;
|
|
struct event_trigger_data *data;
|
|
bool unregistered = false;
|
|
|
|
list_for_each_entry_rcu(data, &file->triggers, list) {
|
|
enable_data = data->private_data;
|
|
if (enable_data &&
|
|
(enable_data->file == test_enable_data->file)) {
|
|
unregistered = true;
|
|
list_del_rcu(&data->list);
|
|
update_cond_flag(file);
|
|
trace_event_trigger_enable_disable(file, 0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (unregistered && data->ops->free)
|
|
data->ops->free(data->ops, data);
|
|
}
|
|
|
|
static struct event_trigger_ops *
|
|
event_enable_get_trigger_ops(char *cmd, char *param)
|
|
{
|
|
struct event_trigger_ops *ops;
|
|
bool enable;
|
|
|
|
enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
|
|
|
|
if (enable)
|
|
ops = param ? &event_enable_count_trigger_ops :
|
|
&event_enable_trigger_ops;
|
|
else
|
|
ops = param ? &event_disable_count_trigger_ops :
|
|
&event_disable_trigger_ops;
|
|
|
|
return ops;
|
|
}
|
|
|
|
static struct event_command trigger_enable_cmd = {
|
|
.name = ENABLE_EVENT_STR,
|
|
.trigger_type = ETT_EVENT_ENABLE,
|
|
.func = event_enable_trigger_func,
|
|
.reg = event_enable_register_trigger,
|
|
.unreg = event_enable_unregister_trigger,
|
|
.get_trigger_ops = event_enable_get_trigger_ops,
|
|
.set_filter = set_trigger_filter,
|
|
};
|
|
|
|
static struct event_command trigger_disable_cmd = {
|
|
.name = DISABLE_EVENT_STR,
|
|
.trigger_type = ETT_EVENT_ENABLE,
|
|
.func = event_enable_trigger_func,
|
|
.reg = event_enable_register_trigger,
|
|
.unreg = event_enable_unregister_trigger,
|
|
.get_trigger_ops = event_enable_get_trigger_ops,
|
|
.set_filter = set_trigger_filter,
|
|
};
|
|
|
|
static __init void unregister_trigger_enable_disable_cmds(void)
|
|
{
|
|
unregister_event_command(&trigger_enable_cmd);
|
|
unregister_event_command(&trigger_disable_cmd);
|
|
}
|
|
|
|
static __init int register_trigger_enable_disable_cmds(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = register_event_command(&trigger_enable_cmd);
|
|
if (WARN_ON(ret < 0))
|
|
return ret;
|
|
ret = register_event_command(&trigger_disable_cmd);
|
|
if (WARN_ON(ret < 0))
|
|
unregister_trigger_enable_disable_cmds();
|
|
|
|
return ret;
|
|
}
|
|
|
|
static __init int register_trigger_traceon_traceoff_cmds(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = register_event_command(&trigger_traceon_cmd);
|
|
if (WARN_ON(ret < 0))
|
|
return ret;
|
|
ret = register_event_command(&trigger_traceoff_cmd);
|
|
if (WARN_ON(ret < 0))
|
|
unregister_trigger_traceon_traceoff_cmds();
|
|
|
|
return ret;
|
|
}
|
|
|
|
__init int register_trigger_cmds(void)
|
|
{
|
|
register_trigger_traceon_traceoff_cmds();
|
|
register_trigger_snapshot_cmd();
|
|
register_trigger_stacktrace_cmd();
|
|
register_trigger_enable_disable_cmds();
|
|
|
|
return 0;
|
|
}
|