linux/kernel/trace/trace_events_trigger.c, branch v4.5

Merge tag 'trace-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2016-01-13T04:04:15Z

Pull tracing updates from Steven Rostedt: "Not much new with tracing for this release. Mostly just clean ups and minor fixes. Here's what else is new: - A new TRACE_EVENT_FN_COND macro, combining both _FN and _COND for those that want both. - New selftest to test the instance create and delete - Better debug output when ftrace fails" * tag 'trace-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits) ftrace: Fix the race between ftrace and insmod ftrace: Add infrastructure for delayed enabling of module functions x86: ftrace: Fix the comments for ftrace_modify_code_direct() tracing: Fix comment to use tracing_on over tracing_enable metag: ftrace: Fix the comments for ftrace_modify_code sh: ftrace: Fix the comments for ftrace_modify_code() ia64: ftrace: Fix the comments for ftrace_modify_code() ftrace: Clean up ftrace_module_init() code ftrace: Join functions ftrace_module_init() and ftrace_init_module() tracing: Introduce TRACE_EVENT_FN_COND macro tracing: Use seq_buf_used() in seq_buf_to_user() instead of len bpf: Constify bpf_verifier_ops structure ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too ftrace: Remove use of control list and ops ftrace: Fix output of enabled_functions for showing tramp ftrace: Fix a typo in comment ftrace: Show all tramps registered to a record on ftrace_bug() ftrace: Add variable ftrace_expected for archs to show expected code ftrace: Add new type to distinguish what kind of ftrace_bug() tracing: Update cond flag when enabling or disabling a trigger ...

kernel/*: switch to memdup_user_nul()

2016-01-04T15:27:55Z

Signed-off-by: Al Viro

tracing: Update cond flag when enabling or disabling a trigger

2015-11-25T20:24:14Z

When a trigger is enabled, the cond flag should be set beforehand, otherwise a trigger that's expecting to process a trace record (e.g. one with post_trigger set) could be invoked without one. Likewise a trigger's cond flag should be reset after it's disabled, not before. Link: http://lkml.kernel.org/r/a420b52a67b1c2d3cab017914362d153255acb99.1448303214.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi Signed-off-by: Daniel Wagner Reviewed-by: Masami Hiramatsu Reviewed-by: Namhyung Kim Tested-by: Masami Hiramatsu Signed-off-by: Steven Rostedt

tracing: Rename ftrace_raw_##call event structures to trace_event_raw_##call

2015-05-14T01:48:40Z

The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The ftrace_raw_##call structures are built by macros for trace events. They have nothing to do with function tracing. Rename them. Signed-off-by: Steven Rostedt

tracing: Rename FTRACE_EVENT_FL_* flags to EVENT_FILE_FL_*

2015-05-13T19:24:57Z

The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The FTRACE_EVENT_FL_* flags are flags to do with the trace_event files in the tracefs directory. They are not related to function tracing. Rename them to a more descriptive name. Signed-off-by: Steven Rostedt

tracing: Rename ftrace_event_name() to trace_event_name()

2015-05-13T18:20:14Z

The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. ftrace_event_name() returns the name of an event tracepoint, has nothing to do with function tracing. Rename it to trace_event_name(). Signed-off-by: Steven Rostedt

tracing: Rename ftrace_event_file to trace_event_file

2015-05-13T18:05:16Z

The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The structure ftrace_event_file is really about trace events and not "ftrace". Rename it to trace_event_file. Signed-off-by: Steven Rostedt

trace: Replace single-character seq_puts with seq_putc

2014-11-14T12:55:55Z

Printing a single character to a seqfile might as well be done with seq_putc instead of seq_puts; this avoids a strlen() call and a memory access. It also shaves another few bytes off the generated code. Link: http://lkml.kernel.org/r/1415479332-25944-4-git-send-email-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Signed-off-by: Steven Rostedt

tracing: Replace seq_printf by simpler equivalents

2014-11-14T02:32:19Z

Using seq_printf to print a simple string or a single character is a lot more expensive than it needs to be, since seq_puts and seq_putc exist. These patches do seq_printf(m, s) -> seq_puts(m, s) seq_printf(m, "%s", s) -> seq_puts(m, s) seq_printf(m, "%c", c) -> seq_putc(m, c) Subsequent patches will simplify further. Link: http://lkml.kernel.org/r/1415479332-25944-2-git-send-email-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Signed-off-by: Steven Rostedt

tracing: Use rcu_dereference_sched() for trace event triggers

2014-05-03T03:12:42Z

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: [] call_timer_fn+0x5/0x1be #1: (&(&pool->lock)->rlock){-.-...}, at: [] __queue_work+0x140/0x283 #2: (&p->pi_lock){-.-.-.}, at: [] try_to_wake_up+0x2e/0x1e8 #3: (&rq->lock){-.-.-.}, at: [] 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: [] dump_stack+0x4f/0x7c [] lockdep_rcu_suspicious+0x107/0x110 [] event_triggers_call+0x99/0x108 [] ftrace_event_buffer_commit+0x42/0xa4 [] ftrace_raw_event_sched_wakeup_template+0x71/0x7c [] ttwu_do_wakeup+0x7f/0xff [] ttwu_do_activate.constprop.126+0x5c/0x61 [] try_to_wake_up+0x1ac/0x1e8 [] wake_up_process+0x36/0x3b [] wake_up_worker+0x24/0x26 [] insert_work+0x5c/0x65 [] __queue_work+0x26c/0x283 [] ? __queue_work+0x283/0x283 [] delayed_work_timer_fn+0x1e/0x20 [] call_timer_fn+0xdf/0x1be^M [] ? call_timer_fn+0x5/0x1be [] ? __queue_work+0x283/0x283 [] run_timer_softirq+0x1a4/0x22f^M [] __do_softirq+0x17b/0x31b^M [] irq_exit+0x42/0x97 [] smp_apic_timer_interrupt+0x37/0x44 [] apic_timer_interrupt+0x6f/0x80 [] ? default_idle+0x21/0x32 [] ? default_idle+0x1f/0x32 [] arch_cpu_idle+0xf/0x11 [] cpu_startup_entry+0x1a3/0x213 [] 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 Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Steven Rostedt