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2013-06-11tracing: Fix outputting formats of x86-tsc and counter when use trace_clockYoshihiro YUNOMAE
Outputting formats of x86-tsc and counter should be a raw format, but after applying the patch(2b6080f28c7cc3efc8625ab71495aae89aeb63a0), the format was changed to nanosec. This is because the global variable trace_clock_id was used. When we use multiple buffers, clock_id of each sub-buffer should be used. Then, this patch uses tr->clock_id instead of the global variable trace_clock_id. [ Basically, this fixes a regression where the multibuffer code changed the trace_clock file to update tr->clock_id but the traces still use the old global trace_clock_id variable, negating the file's effect. The global trace_clock_id variable is obsolete and removed. - SR ] Link: http://lkml.kernel.org/r/20130423013239.22334.7394.stgit@yunodevel Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-06-06tracing: Use current_uid() for critical time tracingSteven Rostedt (Red Hat)
The irqsoff tracer records the max time that interrupts are disabled. There are hooks in the assembly code that calls back into the tracer when interrupts are disabled or enabled. When they are enabled, the tracer checks if the amount of time they were disabled is larger than the previous recorded max interrupts off time. If it is, it creates a snapshot of the currently running trace to store where the last largest interrupts off time was held and how it happened. During testing, this RCU lockdep dump appeared: [ 1257.829021] =============================== [ 1257.829021] [ INFO: suspicious RCU usage. ] [ 1257.829021] 3.10.0-rc1-test+ #171 Tainted: G W [ 1257.829021] ------------------------------- [ 1257.829021] /home/rostedt/work/git/linux-trace.git/include/linux/rcupdate.h:780 rcu_read_lock() used illegally while idle! [ 1257.829021] [ 1257.829021] other info that might help us debug this: [ 1257.829021] [ 1257.829021] [ 1257.829021] RCU used illegally from idle CPU! [ 1257.829021] rcu_scheduler_active = 1, debug_locks = 0 [ 1257.829021] RCU used illegally from extended quiescent state! [ 1257.829021] 2 locks held by trace-cmd/4831: [ 1257.829021] #0: (max_trace_lock){......}, at: [<ffffffff810e2b77>] stop_critical_timing+0x1a3/0x209 [ 1257.829021] #1: (rcu_read_lock){.+.+..}, at: [<ffffffff810dae5a>] __update_max_tr+0x88/0x1ee [ 1257.829021] [ 1257.829021] stack backtrace: [ 1257.829021] CPU: 3 PID: 4831 Comm: trace-cmd Tainted: G W 3.10.0-rc1-test+ #171 [ 1257.829021] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007 [ 1257.829021] 0000000000000001 ffff880065f49da8 ffffffff8153dd2b ffff880065f49dd8 [ 1257.829021] ffffffff81092a00 ffff88006bd78680 ffff88007add7500 0000000000000003 [ 1257.829021] ffff88006bd78680 ffff880065f49e18 ffffffff810daebf ffffffff810dae5a [ 1257.829021] Call Trace: [ 1257.829021] [<ffffffff8153dd2b>] dump_stack+0x19/0x1b [ 1257.829021] [<ffffffff81092a00>] lockdep_rcu_suspicious+0x109/0x112 [ 1257.829021] [<ffffffff810daebf>] __update_max_tr+0xed/0x1ee [ 1257.829021] [<ffffffff810dae5a>] ? __update_max_tr+0x88/0x1ee [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810dbf85>] update_max_tr_single+0x11d/0x12d [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810e2b15>] stop_critical_timing+0x141/0x209 [ 1257.829021] [<ffffffff8109569a>] ? trace_hardirqs_on+0xd/0xf [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810e3057>] time_hardirqs_on+0x2a/0x2f [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff8109550c>] trace_hardirqs_on_caller+0x16/0x197 [ 1257.829021] [<ffffffff8109569a>] trace_hardirqs_on+0xd/0xf [ 1257.829021] [<ffffffff811002b9>] user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810029b4>] do_notify_resume+0x92/0x97 [ 1257.829021] [<ffffffff8154bdca>] int_signal+0x12/0x17 What happened was entering into the user code, the interrupts were enabled and a max interrupts off was recorded. The trace buffer was saved along with various information about the task: comm, pid, uid, priority, etc. The uid is recorded with task_uid(tsk). But this is a macro that uses rcu_read_lock() to retrieve the data, and this happened to happen where RCU is blind (user_enter). As only the preempt and irqs off tracers can have this happen, and they both only have the tsk == current, if tsk == current, use current_uid() instead of task_uid(), as current_uid() does not use RCU as only current can change its uid. This fixes the RCU suspicious splat. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-29tracing: Fix bad parameter passed in branch selftestSteven Rostedt (Red Hat)
The branch selftest calls trace_test_buffer(), but with the new code it expects the first parameter to be a pointer to a struct trace_buffer. All self tests were changed but the branch selftest was missed. This caused either a crash or failed test when the branch selftest was enabled. Link: http://lkml.kernel.org/r/20130529141333.GA24064@localhost Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-28ftrace: Use the rcu _notrace variants for rcu_dereference_raw() and friendsSteven Rostedt
As rcu_dereference_raw() under RCU debug config options can add quite a bit of checks, and that tracing uses rcu_dereference_raw(), these checks happen with the function tracer. The function tracer also happens to trace these debug checks too. This added overhead can livelock the system. Have the function tracer use the new RCU _notrace equivalents that do not do the debug checks for RCU. Link: http://lkml.kernel.org/r/20130528184209.467603904@goodmis.org Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-28ring-buffer: Do not poll non allocated cpu buffersSteven Rostedt (Red Hat)
The tracing infrastructure sets up for possible CPUs, but it uses the ring buffer polling, it is possible to call the ring buffer polling code with a CPU that hasn't been allocated. This will cause a kernel oops when it access a ring buffer cpu buffer that is part of the possible cpus but hasn't been allocated yet as the CPU has never been online. Reported-by: Mauro Carvalho Chehab <mchehab@redhat.com> Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-23tracing: Fix crash when ftrace=nop on the kernel command lineSteven Rostedt (Red Hat)
If ftrace=<tracer> is on the kernel command line, when that tracer is registered, it will be initiated by tracing_set_tracer() to execute that tracer. The nop tracer is just a stub tracer that is used to have no tracer enabled. It is assigned at early bootup as it is the default tracer. But if ftrace=nop is on the kernel command line, the registering of the nop tracer will call tracing_set_tracer() which will try to execute the nop tracer. But it expects tr->current_trace to be assigned something as it usually is assigned to the nop tracer. As it hasn't been assigned to anything yet, it causes the system to crash. The simple fix is to move the tr->current_trace = nop before registering the nop tracer. The functionality is still the same as the nop tracer doesn't do anything anyway. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-16tracing: Return -EBUSY when event_enable_func() fails to get moduleMasami Hiramatsu
Since try_module_get() returns false( = 0) when it fails to pindown a module, event_enable_func() returns 0 which means "succeed". This can cause a kernel panic when the entry is removed, because the event is already released. This fixes the bug by returning -EBUSY, because the reason why it fails is that the module is being removed at that time. Link: http://lkml.kernel.org/r/20130516114848.13508.97899.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15tracing/kprobes: Make print_*probe_event staticMasami Hiramatsu
According to sparse warning, print_*probe_event static because those functions are not directly called from outside. Link: http://lkml.kernel.org/r/20130513115839.6545.83067.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15tracing/kprobes: Fix a sparse warning for incorrect type in assignmentMasami Hiramatsu
Fix a sparse warning about the rcu operated pointer is defined without __rcu address space. Link: http://lkml.kernel.org/r/20130513115837.6545.23322.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15tracing/kprobes: Use rcu_dereference_raw for tp->filesMasami Hiramatsu
Use rcu_dereference_raw() for accessing tp->files. Because the write-side uses rcu_assign_pointer() for memory barrier, the read-side also has to use rcu_dereference_raw() with read memory barrier. Link: http://lkml.kernel.org/r/20130513115834.6545.17022.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15tracing: Fix leaks of filter predsSteven Rostedt (Red Hat)
Special preds are created when folding a series of preds that can be done in serial. These are allocated in an ops field of the pred structure. But they were never freed, causing memory leaks. This was discovered using the kmemleak checker: unreferenced object 0xffff8800797fd5e0 (size 32): comm "swapper/0", pid 1, jiffies 4294690605 (age 104.608s) hex dump (first 32 bytes): 00 00 01 00 03 00 05 00 07 00 09 00 0b 00 0d 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff814b52af>] kmemleak_alloc+0x73/0x98 [<ffffffff8111ff84>] kmemleak_alloc_recursive.constprop.42+0x16/0x18 [<ffffffff81120e68>] __kmalloc+0xd7/0x125 [<ffffffff810d47eb>] kcalloc.constprop.24+0x2d/0x2f [<ffffffff810d4896>] fold_pred_tree_cb+0xa9/0xf4 [<ffffffff810d3781>] walk_pred_tree+0x47/0xcc [<ffffffff810d5030>] replace_preds.isra.20+0x6f8/0x72f [<ffffffff810d50b5>] create_filter+0x4e/0x8b [<ffffffff81b1c30d>] ftrace_test_event_filter+0x5a/0x155 [<ffffffff8100028d>] do_one_initcall+0xa0/0x137 [<ffffffff81afbedf>] kernel_init_freeable+0x14d/0x1dc [<ffffffff814b24b7>] kernel_init+0xe/0xdb [<ffffffff814d539c>] ret_from_fork+0x7c/0xb0 [<ffffffffffffffff>] 0xffffffffffffffff Cc: Tom Zanussi <tzanussi@gmail.com> Cc: stable@vger.kernel.org # 2.6.39+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-11Merge tag 'trace-fixes-v3.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing/kprobes update from Steven Rostedt: "The majority of these changes are from Masami Hiramatsu bringing kprobes up to par with the latest changes to ftrace (multi buffering and the new function probes). He also discovered and fixed some bugs in doing so. When pulling in his patches, I also found a few minor bugs as well and fixed them. This also includes a compile fix for some archs that select the ring buffer but not tracing. I based this off of the last patch you took from me that fixed the merge conflict error, as that was the commit that had all the changes I needed for this set of changes." * tag 'trace-fixes-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Support soft-mode disabling tracing/kprobes: Support ftrace_event_file base multibuffer tracing/kprobes: Pass trace_probe directly from dispatcher tracing/kprobes: Increment probe hit-count even if it is used by perf tracing/kprobes: Use bool for retprobe checker ftrace: Fix function probe when more than one probe is added ftrace: Fix the output of enabled_functions debug file ftrace: Fix locking in register_ftrace_function_probe() tracing: Add helper function trace_create_new_event() to remove duplicate code tracing: Modify soft-mode only if there's no other referrer tracing: Indicate enabled soft-mode in enable file tracing/kprobes: Fix to increment return event probe hit-count ftrace: Cleanup regex_lock and ftrace_lock around hash updating ftrace, kprobes: Fix a deadlock on ftrace_regex_lock ftrace: Have ftrace_regex_write() return either read or error tracing: Return error if register_ftrace_function_probe() fails for event_enable_func() tracing: Don't succeed if event_enable_func did not register anything ring-buffer: Select IRQ_WORK
2013-05-09tracing/kprobes: Support soft-mode disablingMasami Hiramatsu
Support soft-mode disabling on kprobe-based dynamic events. Soft-disabling is just ignoring recording if the soft disabled flag is set. Link: http://lkml.kernel.org/r/20130509054454.30398.7237.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing/kprobes: Support ftrace_event_file base multibufferMasami Hiramatsu
Support multi-buffer on kprobe-based dynamic events by using ftrace_event_file. Link: http://lkml.kernel.org/r/20130509054449.30398.88343.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing/kprobes: Pass trace_probe directly from dispatcherMasami Hiramatsu
Pass the pointer of struct trace_probe directly from probe dispatcher to handlers. This removes redundant container_of macro uses. Same thing has already done in trace_uprobe. Link: http://lkml.kernel.org/r/20130509054441.30398.69112.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing/kprobes: Increment probe hit-count even if it is used by perfMasami Hiramatsu
Increment probe hit-count for profiling even if it is used by perf tool. Same thing has already done in trace_uprobe. Link: http://lkml.kernel.org/r/20130509054436.30398.21133.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing/kprobes: Use bool for retprobe checkerMasami Hiramatsu
Use bool instead of int for kretprobe checker. Link: http://lkml.kernel.org/r/20130509054431.30398.38561.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09ftrace: Fix function probe when more than one probe is addedSteven Rostedt (Red Hat)
When the first function probe is added and the function tracer is updated the functions are modified to call the probe. But when a second function is added, it updates the function records to have the second function also update, but it fails to update the actual function itself. This prevents the second (or third or forth and so on) probes from having their functions called. # echo vfs_symlink:enable_event:sched:sched_switch > set_ftrace_filter # echo vfs_unlink:enable_event:sched:sched_switch > set_ftrace_filter # cat trace # tracer: nop # # entries-in-buffer/entries-written: 0/0 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | # touch /tmp/a # rm /tmp/a # cat trace # tracer: nop # # entries-in-buffer/entries-written: 0/0 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | # ln -s /tmp/a # cat trace # tracer: nop # # entries-in-buffer/entries-written: 414/414 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | <idle>-0 [000] d..3 2847.923031: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=bash next_pid=2786 next_prio=120 <...>-3114 [001] d..4 2847.923035: sched_switch: prev_comm=ln prev_pid=3114 prev_prio=120 prev_state=x ==> next_comm=swapper/1 next_pid=0 next_prio=120 bash-2786 [000] d..3 2847.923535: sched_switch: prev_comm=bash prev_pid=2786 prev_prio=120 prev_state=S ==> next_comm=kworker/0:1 next_pid=34 next_prio=120 kworker/0:1-34 [000] d..3 2847.923552: sched_switch: prev_comm=kworker/0:1 prev_pid=34 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120 <idle>-0 [002] d..3 2847.923554: sched_switch: prev_comm=swapper/2 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=sshd next_pid=2783 next_prio=120 sshd-2783 [002] d..3 2847.923660: sched_switch: prev_comm=sshd prev_pid=2783 prev_prio=120 prev_state=S ==> next_comm=swapper/2 next_pid=0 next_prio=120 Still need to update the functions even though the probe itself does not need to be registered again when added a new probe. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09ftrace: Fix the output of enabled_functions debug fileSteven Rostedt (Red Hat)
The enabled_functions debugfs file was created to be able to see what functions have been modified from nops to calling a tracer. The current method uses the counter in the function record. As when a ftrace_ops is registered to a function, its count increases. But that doesn't mean that the function is actively being traced. /proc/sys/kernel/ftrace_enabled can be set to zero which would disable it, as well as something can go wrong and we can think its enabled when only the counter is set. The record's FTRACE_FL_ENABLED flag is set or cleared when its function is modified. That is a much more accurate way of knowing what function is enabled or not. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09ftrace: Fix locking in register_ftrace_function_probe()Steven Rostedt (Red Hat)
The iteration of the ftrace function list and the call to ftrace_match_record() need to be protected by the ftrace_lock. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing: Add helper function trace_create_new_event() to remove duplicate codeSteven Rostedt (Red Hat)
Both __trace_add_new_event() and __trace_early_add_new_event() do basically the same thing, except that __trace_add_new_event() does a little more. Instead of having duplicate code between the two functions, add a helper function trace_create_new_event() that both can use. This will help against having bugs fixed in one function but not the other. Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing: Modify soft-mode only if there's no other referrerMasami Hiramatsu
Modify soft-mode flag only if no other soft-mode referrer (currently only the ftrace triggers) by using a reference counter in each ftrace_event_file. Without this fix, adding and removing several different enable/disable_event triggers on the same event clear soft-mode bit from the ftrace_event_file. This also happens with a typo of glob on setting triggers. e.g. # echo vfs_symlink:enable_event:net:netif_rx > set_ftrace_filter # cat events/net/netif_rx/enable 0* # echo typo_func:enable_event:net:netif_rx > set_ftrace_filter # cat events/net/netif_rx/enable 0 # cat set_ftrace_filter #### all functions enabled #### vfs_symlink:enable_event:net:netif_rx:unlimited As above, we still have a trigger, but soft-mode is gone. Link: http://lkml.kernel.org/r/20130509054429.30398.7464.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: David Sharp <dhsharp@google.com> Cc: Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing: Indicate enabled soft-mode in enable fileMasami Hiramatsu
Indicate enabled soft-mode event as "1*" in "enable" file for each event, because it can be soft-disabled when disable_event trigger is hit. Link: http://lkml.kernel.org/r/20130509054426.30398.28202.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing/kprobes: Fix to increment return event probe hit-countMasami Hiramatsu
Fix to increment probe hit-count for function return event. Link: http://lkml.kernel.org/r/20130509054424.30398.34058.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09ftrace: Cleanup regex_lock and ftrace_lock around hash updatingMasami Hiramatsu
Cleanup regex_lock and ftrace_lock locking points around ftrace_ops hash update code. The new rule is that regex_lock protects ops->*_hash read-update-write code for each ftrace_ops. Usually, hash update is done by following sequence. 1. allocate a new local hash and copy the original hash. 2. update the local hash. 3. move(actually, copy) back the local hash to ftrace_ops. 4. update ftrace entries if needed. 5. release the local hash. This makes regex_lock protect #1-#4, and ftrace_lock to protect #3, #4 and adding and removing ftrace_ops from the ftrace_ops_list. The ftrace_lock protects #3 as well because the move functions update the entries too. Link: http://lkml.kernel.org/r/20130509054421.30398.83411.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09ftrace, kprobes: Fix a deadlock on ftrace_regex_lockMasami Hiramatsu
Fix a deadlock on ftrace_regex_lock which happens when setting an enable_event trigger on dynamic kprobe event as below. ---- sh-2.05b# echo p vfs_symlink > kprobe_events sh-2.05b# echo vfs_symlink:enable_event:kprobes:p_vfs_symlink_0 > set_ftrace_filter ============================================= [ INFO: possible recursive locking detected ] 3.9.0+ #35 Not tainted --------------------------------------------- sh/72 is trying to acquire lock: (ftrace_regex_lock){+.+.+.}, at: [<ffffffff810ba6c1>] ftrace_set_hash+0x81/0x1f0 but task is already holding lock: (ftrace_regex_lock){+.+.+.}, at: [<ffffffff810b7cbd>] ftrace_regex_write.isra.29.part.30+0x3d/0x220 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(ftrace_regex_lock); lock(ftrace_regex_lock); *** DEADLOCK *** ---- To fix that, this introduces a finer regex_lock for each ftrace_ops. ftrace_regex_lock is too big of a lock which protects all filter/notrace_hash operations, but it doesn't need to be a global lock after supporting multiple ftrace_ops because each ftrace_ops has its own filter/notrace_hash. Link: http://lkml.kernel.org/r/20130509054417.30398.84254.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> [ Added initialization flag and automate mutex initialization for non ftrace.c ftrace_probes. ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09ftrace: Have ftrace_regex_write() return either read or errorSteven Rostedt (Red Hat)
As ftrace_regex_write() reads the result of ftrace_process_regex() which can sometimes return a positive number, only consider a failure if the return is negative. Otherwise, it will skip possible other registered probes and by returning a positive number that wasn't read, it will confuse the user processes doing the writing. Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing: Return error if register_ftrace_function_probe() fails for ↵Steven Rostedt (Red Hat)
event_enable_func() register_ftrace_function_probe() returns the number of functions it registered, which can be zero, it can also return a negative number if something went wrong. But event_enable_func() only checks for the case that it didn't register anything, it needs to also check for the case that something went wrong and return that error code as well. Added some comments about the code as well, to make it more understandable. Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-09tracing: Don't succeed if event_enable_func did not register anythingMasami Hiramatsu
Return 0 instead of the number of activated ftrace function probes if event_enable_func succeeded and return an error code if it failed or did not register any functions. But it currently returns the number of registered functions and if it didn't register anything, it returns 0, but that is considered success. This also fixes the return value. As if it succeeds, it returns the number of functions that were enabled, which is returned back to the user in ftrace_regex_write (the write() return code). If only one function is enabled, then the return code of the write is one, and this can confuse the user program in thinking it only wrote 1 byte. Link: http://lkml.kernel.org/r/20130509054413.30398.55650.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> [ Rewrote change log to reflect that this fixes two bugs - SR ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-08Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "It might look big in volume, but when categorized, not a lot of drivers are touched. The pull request contains: - mtip32xx fixes from Micron. - A slew of drbd updates, this time in a nicer series. - bcache, a flash/ssd caching framework from Kent. - Fixes for cciss" * 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits) bcache: Use bd_link_disk_holder() bcache: Allocator cleanup/fixes cciss: bug fix to prevent cciss from loading in kdump crash kernel cciss: add cciss_allow_hpsa module parameter drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions mtip32xx: Workaround for unaligned writes bcache: Make sure blocksize isn't smaller than device blocksize bcache: Fix merge_bvec_fn usage for when it modifies the bvm bcache: Correctly check against BIO_MAX_PAGES bcache: Hack around stuff that clones up to bi_max_vecs bcache: Set ra_pages based on backing device's ra_pages bcache: Take data offset from the bdev superblock. mtip32xx: mtip32xx: Disable TRIM support mtip32xx: fix a smatch warning bcache: Disable broken btree fuzz tester bcache: Fix a format string overflow bcache: Fix a minor memory leak on device teardown bcache: Documentation updates bcache: Use WARN_ONCE() instead of __WARN() bcache: Add missing #include <linux/prefetch.h> ...
2013-05-03ring-buffer: Select IRQ_WORKSteven Rostedt (Red Hat)
As the wake up logic for waiters on the buffer has been moved from the tracing code to the ring buffer, it requires also adding IRQ_WORK as the wake up code is performed via irq_work. This fixes compile breakage when a user of the ring buffer is selected but tracing and irq_work are not. Link http://lkml.kernel.org/r/20130503115332.GT8356@rric.localhost Cc: Arnd Bergmann <arnd@arndb.de> Reported-by: Robert Richter <rric@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-04-30Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Features: - Add "uretprobes" - an optimization to uprobes, like kretprobes are an optimization to kprobes. "perf probe -x file sym%return" now works like kretprobes. By Oleg Nesterov. - Introduce per core aggregation in 'perf stat', from Stephane Eranian. - Add memory profiling via PEBS, from Stephane Eranian. - Event group view for 'annotate' in --stdio, --tui and --gtk, from Namhyung Kim. - Add support for AMD NB and L2I "uncore" counters, by Jacob Shin. - Add Ivy Bridge-EP uncore support, by Zheng Yan - IBM zEnterprise EC12 oprofile support patchlet from Robert Richter. - Add perf test entries for checking breakpoint overflow signal handler issues, from Jiri Olsa. - Add perf test entry for for checking number of EXIT events, from Namhyung Kim. - Add perf test entries for checking --cpu in record and stat, from Jiri Olsa. - Introduce perf stat --repeat forever, from Frederik Deweerdt. - Add --no-demangle to report/top, from Namhyung Kim. - PowerPC fixes plus a couple of cleanups/optimizations in uprobes and trace_uprobes, by Oleg Nesterov. Various fixes and refactorings: - Fix dependency of the python binding wrt libtraceevent, from Naohiro Aota. - Simplify some perf_evlist methods and to allow 'stat' to share code with 'record' and 'trace', by Arnaldo Carvalho de Melo. - Remove dead code in related to libtraceevent integration, from Namhyung Kim. - Revert "perf sched: Handle PERF_RECORD_EXIT events" to get 'perf sched lat' back working, by Arnaldo Carvalho de Melo - We don't use Newt anymore, just plain libslang, by Arnaldo Carvalho de Melo. - Kill a bunch of die() calls, from Namhyung Kim. - Fix build on non-glibc systems due to libio.h absence, from Cody P Schafer. - Remove some perf_session and tracing dead code, from David Ahern. - Honor parallel jobs, fix from Borislav Petkov - Introduce tools/lib/lk library, initially just removing duplication among tools/perf and tools/vm. from Borislav Petkov ... and many more I missed to list, see the shortlog and git log for more details." * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (136 commits) perf/x86/intel/P4: Robistify P4 PMU types perf/x86/amd: Fix AMD NB and L2I "uncore" support perf/x86/amd: Remove old-style NB counter support from perf_event_amd.c perf/x86: Check all MSRs before passing hw check perf/x86/amd: Add support for AMD NB and L2I "uncore" counters perf/x86/intel: Add Ivy Bridge-EP uncore support perf/x86/intel: Fix SNB-EP CBO and PCU uncore PMU filter management perf/x86: Avoid kfree() in CPU_{STARTING,DYING} uprobes/perf: Avoid perf_trace_buf_prepare/submit if ->perf_events is empty uprobes/tracing: Don't pass addr=ip to perf_trace_buf_submit() uprobes/tracing: Change create_trace_uprobe() to support uretprobes uprobes/tracing: Make seq_printf() code uretprobe-friendly uprobes/tracing: Make register_uprobe_event() paths uretprobe-friendly uprobes/tracing: Make uprobe_{trace,perf}_print() uretprobe-friendly uprobes/tracing: Introduce is_ret_probe() and uretprobe_dispatcher() uprobes/tracing: Introduce uprobe_{trace,perf}_print() helpers uprobes/tracing: Generalize struct uprobe_trace_entry_head uprobes/tracing: Kill the pointless local_save_flags/preempt_count calls uprobes/tracing: Kill the pointless seq_print_ip_sym() call uprobes/tracing: Kill the pointless task_pt_regs() calls ...
2013-04-30tracing: Fix small merge bugSteven Rostedt
During the 3.10 merge, a conflict happened and the resolution was almost, but not quite, correct. An if statement was reversed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> [ Duh. That was just silly of me - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29Merge tag 'trace-3.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "Along with the usual minor fixes and clean ups there are a few major changes with this pull request. 1) Multiple buffers for the ftrace facility This feature has been requested by many people over the last few years. I even heard that Google was about to implement it themselves. I finally had time and cleaned up the code such that you can now create multiple instances of the ftrace buffer and have different events go to different buffers. This way, a low frequency event will not be lost in the noise of a high frequency event. Note, currently only events can go to different buffers, the tracers (ie function, function_graph and the latency tracers) still can only be written to the main buffer. 2) The function tracer triggers have now been extended. The function tracer had two triggers. One to enable tracing when a function is hit, and one to disable tracing. Now you can record a stack trace on a single (or many) function(s), take a snapshot of the buffer (copy it to the snapshot buffer), and you can enable or disable an event to be traced when a function is hit. 3) A perf clock has been added. A "perf" clock can be chosen to be used when tracing. This will cause ftrace to use the same clock as perf uses, and hopefully this will make it easier to interleave the perf and ftrace data for analysis." * tag 'trace-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (82 commits) tracepoints: Prevent null probe from being added tracing: Compare to 1 instead of zero for is_signed_type() tracing: Remove obsolete macro guard _TRACE_PROFILE_INIT ftrace: Get rid of ftrace_profile_bits tracing: Check return value of tracing_init_dentry() tracing: Get rid of unneeded key calculation in ftrace_hash_move() tracing: Reset ftrace_graph_filter_enabled if count is zero tracing: Fix off-by-one on allocating stat->pages kernel: tracing: Use strlcpy instead of strncpy tracing: Update debugfs README file tracing: Fix ftrace_dump() tracing: Rename trace_event_mutex to trace_event_sem tracing: Fix comment about prefix in arch_syscall_match_sym_name() tracing: Convert trace_destroy_fields() to static tracing: Move find_event_field() into trace_events.c tracing: Use TRACE_MAX_PRINT instead of constant tracing: Use pr_warn_once instead of open coded implementation ring-buffer: Add ring buffer startup selftest tracing: Bring Documentation/trace/ftrace.txt up to date tracing: Add "perf" trace_clock ... Conflicts: kernel/trace/ftrace.c kernel/trace/trace.c
2013-04-21Merge branch 'perf/urgent' into perf/coreIngo Molnar
Conflicts: arch/x86/kernel/cpu/perf_event_intel.c Merge in the latest fixes before applying new patches, resolve the conflict. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-04-18Revert "block: add missing block_bio_complete() tracepoint"Linus Torvalds
This reverts commit 3a366e614d0837d9fc23f78cdb1a1186ebc3387f. Wanlong Gao reports that it causes a kernel panic on his machine several minutes after boot. Reverting it removes the panic. Jens says: "It's not quite clear why that is yet, so I think we should just revert the commit for 3.9 final (which I'm assuming is pretty close). The wifi is crap at the LSF hotel, so sending this email instead of queueing up a revert and pull request." Reported-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Requested-by: Jens Axboe <axboe@kernel.dk> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-15uprobes/perf: Avoid perf_trace_buf_prepare/submit if ->perf_events is emptyOleg Nesterov
perf_trace_buf_prepare() + perf_trace_buf_submit() make no sense if this task/CPU has no active counters. Change uprobe_perf_print() to return if hlist_empty(call->perf_events). Note: this is not uprobe-specific, we can change other users too. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-04-14Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Misc fixlets" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Fix error return code ftrace: Fix strncpy() use, use strlcpy() instead of strncpy() perf: Fix strncpy() use, use strlcpy() instead of strncpy() perf: Fix strncpy() use, always make sure it's NUL terminated perf: Fix ring_buffer perf_output_space() boundary calculation perf/x86: Fix uninitialized pt_regs in intel_pmu_drain_bts_buffer()
2013-04-13uprobes/tracing: Don't pass addr=ip to perf_trace_buf_submit()Oleg Nesterov
uprobe_perf_print() passes addr=ip to perf_trace_buf_submit() for no reason. This sets perf_sample_data->addr for PERF_SAMPLE_ADDR, we already have perf_sample_data->ip initialized if PERF_SAMPLE_IP. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2013-04-13uprobes/tracing: Change create_trace_uprobe() to support uretprobesOleg Nesterov
Finally change create_trace_uprobe() to check if argv[0][0] == 'r' and pass the correct "is_ret" to alloc_trace_uprobe(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Make seq_printf() code uretprobe-friendlyOleg Nesterov
Change probes_seq_show() and print_uprobe_event() to check is_ret_probe() and print the correct data. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Make register_uprobe_event() paths uretprobe-friendlyOleg Nesterov
Change uprobe_event_define_fields(), and __set_print_fmt() to check is_ret_probe() and use the appropriate format/fields. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Make uprobe_{trace,perf}_print() uretprobe-friendlyOleg Nesterov
Change uprobe_trace_print() and uprobe_perf_print() to check is_ret_probe() and fill ring_buffer_event accordingly. Also change uprobe_trace_func() and uprobe_perf_func() to not _print() if is_ret_probe() is true. Note that we keep ->handler() nontrivial even for uretprobe, we need this for filtering and for other potential extensions. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Introduce is_ret_probe() and uretprobe_dispatcher()Oleg Nesterov
Create the new functions we need to support uretprobes, and change alloc_trace_uprobe() to initialize consumer.ret_handler if the new "is_ret" argument is true. Curently this argument is always false, so the new code is never called and is_ret_probe(tu) is false too. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Introduce uprobe_{trace,perf}_print() helpersOleg Nesterov
Extract the output code from uprobe_trace_func() and uprobe_perf_func() into the new helpers, they will be used by ->ret_handler() too. We also add the unused "unsigned long func" argument in advance, to simplify the next changes. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Generalize struct uprobe_trace_entry_headOleg Nesterov
struct uprobe_trace_entry_head has a single member for reporting, "unsigned long ip". If we want to support uretprobes we need to create another struct which has "func" and "ret_ip" and duplicate a lot of functions, like trace_kprobe.c does. To avoid this copy-and-paste horror we turn ->ip into ->vaddr[] and add couple of trivial helpers to calculate sizeof/data. This uglifies the code a bit, but this allows us to avoid a lot more complications later, when we add the support for ret-probes. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Kill the pointless local_save_flags/preempt_count callsOleg Nesterov
uprobe_trace_func() is never called with irqs or preemption disabled, no need to ask preempt_count() or local_save_flags(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Kill the pointless seq_print_ip_sym() callOleg Nesterov
seq_print_ip_sym(ip) in print_uprobe_event() is pointless, kallsyms_lookup(ip) can not resolve a user-space address. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-13uprobes/tracing: Kill the pointless task_pt_regs() callsOleg Nesterov
uprobe_trace_func() and uprobe_perf_func() do not need task_pt_regs(), we already have "struct pt_regs *regs". Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Anton Arapov <anton@redhat.com>
2013-04-12ftrace: Get rid of ftrace_profile_bitsNamhyung Kim
It seems that function profiler's hash size is fixed at 1024. Add and use FTRACE_PROFILE_HASH_BITS instead and update hash size macro. Link: http://lkml.kernel.org/r/1365551750-4504-1-git-send-email-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>