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* tracing: Fix stacktrace of latency tracers (irqsoff and friends)Steven Rostedt2012-04-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | While debugging a latency with someone on IRC (mirage335) on #linux-rt (OFTC), we discovered that the stacktrace output of the latency tracers (preemptirqsoff) was empty. This bug was caused by the creation of the dynamic length stack trace again (like commit 12b5da3 "tracing: Fix ent_size in trace output" was). This bug is caused by the latency tracers requiring the next event to determine the time between the current event and the next. But by grabbing the next event, the iter->ent_size is set to the next event instead of the current one. As the stacktrace event is the last event, this makes the ent_size zero and causes nothing to be printed for the stack trace. The dynamic stacktrace uses the ent_size to determine how much of the stack can be printed. The ent_size of zero means no stack. The simple fix is to save the iter->ent_size before finding the next event. Note, mirage335 asked to remain anonymous from LKML and git, so I will not add the Reported-by and Tested-by tags, even though he did report the issue and tested the fix. Cc: stable@vger.kernel.org # 3.1+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Fix regression with tracing_onSteven Rostedt2012-04-16
| | | | | | | | | | | | | | | | The change to make tracing_on affect only the ftrace ring buffer, caused a bug where it wont affect any ring buffer. The problem was that the buffer of the trace_array was passed to the write function and not the trace array itself. The trace_array can change the buffer when running a latency tracer. If this happens, then the buffer being disabled may not be the buffer currently used by ftrace. This will cause the tracing_on file to become useless. The simple fix is to pass the trace_array to the write function instead of the buffer. Then the actual buffer may be changed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Fix build breakage without CONFIG_PERF_EVENTS (again)Mark Brown2012-04-13
| | | | | | | | | | | | | | | | | | | Today's -next fails to link for me: kernel/built-in.o:(.data+0x178e50): undefined reference to `perf_ftrace_event_register' It looks like multiple fixes have been merged for the issue fixed by commit fa73dc9 (tracing: Fix build breakage without CONFIG_PERF_EVENTS) though I can't identify the other changes that have gone in at the minute, it's possible that the changes which caused the breakage fixed by the previous commit got dropped but the fix made it in. Link: http://lkml.kernel.org/r/1334307179-21255-1-git-send-email-broonie@opensource.wolfsonmicro.com Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds2012-04-05
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge batch of fixes from Andrew Morton: "The simple_open() cleanup was held back while I wanted for laggards to merge things. I still need to send a few checkpoint/restore patches. I've been wobbly about merging them because I'm wobbly about the overall prospects for success of the project. But after speaking with Pavel at the LSF conference, it sounds like they're further toward completion than I feared - apparently davem is at the "has stopped complaining" stage regarding the net changes. So I need to go back and re-review those patchs and their (lengthy) discussion." * emailed from Andrew Morton <akpm@linux-foundation.org>: (16 patches) memcg swap: use mem_cgroup_uncharge_swap fix backlight: add driver for DA9052/53 PMIC v1 C6X: use set_current_blocked() and block_sigmask() MAINTAINERS: add entry for sparse checker MAINTAINERS: fix REMOTEPROC F: typo alpha: use set_current_blocked() and block_sigmask() simple_open: automatically convert to simple_open() scripts/coccinelle/api/simple_open.cocci: semantic patch for simple_open() libfs: add simple_open() hugetlbfs: remove unregister_filesystem() when initializing module drivers/rtc/rtc-88pm860x.c: fix rtc irq enable callback fs/xattr.c:setxattr(): improve handling of allocation failures fs/xattr.c:listxattr(): fall back to vmalloc() if kmalloc() failed fs/xattr.c: suppress page allocation failure warnings from sys_listxattr() sysrq: use SEND_SIG_FORCED instead of force_sig() proc: fix mount -t proc -o AAA
| * simple_open: automatically convert to simple_open()Stephen Boyd2012-04-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: <smpl> @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; </smpl> [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | tracing: Fix ent_size in trace outputSteven Rostedt2012-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When reading the trace file, the records of each of the per_cpu buffers are examined to find the next event to print out. At the point of looking at the event, the size of the event is recorded. But if the first event is chosen, the other events in the other CPU buffers will reset the event size that is stored in the iterator descriptor, causing the event size passed to the output functions to be incorrect. In most cases this is not a problem, but for the case of stack traces, it is. With the change to the stack tracing to record a dynamic number of back traces, the output depends on the size of the entry instead of the fixed 8 back traces. When the entry size is not correct, the back traces would not be fully printed. Note, reading from the per-cpu trace files were not affected. Reported-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | Merge branch 'linus' into perf/urgentIngo Molnar2012-03-26
|\| | | | | | | | | | | Merge reason: we need to fix a non-trivial merge conflict. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * Merge branch 'for-linus' of ↵Linus Torvalds2012-03-21
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 1 from Al Viro: "This is _not_ all; in particular, Miklos' and Jan's stuff is not there yet." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits) ext4: initialization of ext4_li_mtx needs to be done earlier debugfs-related mode_t whack-a-mole hfsplus: add an ioctl to bless files hfsplus: change finder_info to u32 hfsplus: initialise userflags qnx4: new helper - try_extent() qnx4: get rid of qnx4_bread/qnx4_getblk take removal of PF_FORKNOEXEC to flush_old_exec() trim includes in inode.c um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it um: embed ->stub_pages[] into mmu_context gadgetfs: list_for_each_safe() misuse ocfs2: fix leaks on failure exits in module_init ecryptfs: make register_filesystem() the last potential failure exit ntfs: forgets to unregister sysctls on register_filesystem() failure logfs: missing cleanup on register_filesystem() failure jfs: mising cleanup on register_filesystem() failure make configfs_pin_fs() return root dentry on success configfs: configfs_create_dir() has parent dentry in dentry->d_parent configfs: sanitize configfs_create() ...
| | * constify path argument of trace_seq_path()Al Viro2012-03-20
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | Merge branch 'tip/perf/urgent' of ↵Ingo Molnar2012-03-24
|\ \ \ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/urgent
| * | | tracing: Fix ftrace stack trace entriesWolfgang Mauerer2012-03-22
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | 8 hex characters tell only half the tale for 64 bit CPUs, so use the appropriate length. Link: http://lkml.kernel.org/r/1332411501-8059-2-git-send-email-wolfgang.mauerer@siemens.com Cc: stable@vger.kernel.org Signed-off-by: Wolfgang Mauerer <wolfgang.mauerer@siemens.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Fix build breakage without CONFIG_PERF_EVENTSMark Brown2012-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Today's -next fails to build for me: CC kernel/trace/trace_export.o In file included from kernel/trace/trace_export.c:197: kernel/trace/trace_entries.h:58: error: 'perf_ftrace_event_register' undeclared here (not in a function) make[2]: *** [kernel/trace/trace_export.o] Error 1 make[1]: *** [kernel/trace] Error 2 make: *** [kernel] Error 2 because as of ced390 (ftrace, perf: Add support to use function tracepoint in perf) perf_trace_event_register() is declared in trace.h only if CONFIG_PERF_EVENTS is enabled but I don't have that set. Ensure that we always have a definition of perf_trace_event_register() by making the definition unconditional. Link: http://lkml.kernel.org/r/1330426967-17067-1-git-send-email-broonie@opensource.wolfsonmicro.com Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | ftrace: Fix function_graph for archs that test ftrace_trace_functionRajesh Bhagat2012-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When CONFIG_DYNAMIC_FTRACE is not set, some archs (ARM) test the variable function_trace_function to determine if it should call the function tracer. If it is not set to ftrace_stub, then it will call the function and return, and not call the function graph tracer. But some of these archs (ARM) do not have the assembly code to test if function tracing is enabled or not (quick stop of tracing) and it calls the helper routine ftrace_test_stop_func() instead. If function tracer is enabled and then disabled, the variable ftrace_trace_function is still set to the helper routine ftrace_test_stop_func(), and not to ftrace_stub. This will prevent the function graph tracer from ever running. Output before patch /debug/tracing # echo function > current_tracer /debug/tracing # echo function_graph > current_tracer /debug/tracing # cat trace Output after patch /debug/tracing # echo function > current_tracer /debug/tracing # echo function_graph > current_tracer /debug/tracing # cat trace 0) ! 253.375 us | } /* irq_enter */ 0) | generic_handle_irq() { 0) | handle_fasteoi_irq() { 0) 9.208 us | _raw_spin_lock(); 0) | handle_irq_event() { 0) | handle_irq_event_percpu() { Signed-off-by: Rajesh Bhagat <rajesh.lnx@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Keep NMI watchdog from triggering when dumping traceSteven Rostedt2012-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As ftrace_dump() (called by ftrace_dump_on_oops) disables interrupts as it dumps its output to the console, it can keep interrupts disabled for long periods of time. This is likely to trigger the NMI watchdog, and it can disrupt the output of critical data. Add a touch_nmi_watchdog() to each event that is written to the screen to keep the NMI watchdog from affecting the output. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Do not select FRAME_POINTER on PPCGerlando Falauto2012-02-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On PowerPC, FUNCTION_TRACER selects FRAME_POINTER, even though the architecture does not support it. This causes the following warning: warning: (LOCKDEP && FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && FUNCTION_TRACER && KMEMCHECK) selects FRAME_POINTER which has unmet direct dependencies (DEBUG_KERNEL && (CRIS || M68K || FRV || UML || AVR32 || SUPERH || BLACKFIN || MN10300) || ARCH_WANT_FRAME_POINTERS) So remove the warning by adding the extra condition "if !PPC" to FUNCTION_TRACER for FRAME_POINTER selection Link: http://lkml.kernel.org/r/1330330101-8618-1-git-send-email-gerlando.falauto@keymile.com Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing/ring-buffer: Only have tracing_on disable tracing buffersSteven Rostedt2012-02-22
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | As the ring-buffer code is being used by other facilities in the kernel, having tracing_on file disable *all* buffers is not a desired affect. It should only disable the ftrace buffers that are being used. Move the code into the trace.c file and use the buffer disabling for tracing_on() and tracing_off(). This way only the ftrace buffers will be affected by them and other kernel utilities will not be confused to why their output suddenly stopped. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace, perf: Add filter support for function trace eventJiri Olsa2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding support to filter function trace event via perf interface. It is now possible to use filter interface in the perf tool like: perf record -e ftrace:function --filter="(ip == mm_*)" ls The filter syntax is restricted to the the 'ip' field only, and following operators are accepted '==' '!=' '||', ending up with the filter strings like: ip == f1[, ]f2 ... || ip != f3[, ]f4 ... with comma ',' or space ' ' as a function separator. If the space ' ' is used as a separator, the right side of the assignment needs to be enclosed in double quotes '"', e.g.: perf record -e ftrace:function --filter '(ip == do_execve,sys_*,ext*)' ls perf record -e ftrace:function --filter '(ip == "do_execve,sys_*,ext*")' ls perf record -e ftrace:function --filter '(ip == "do_execve sys_* ext*")' ls The '==' operator adds trace filter with same effect as would be added via set_ftrace_filter file. The '!=' operator adds trace filter with same effect as would be added via set_ftrace_notrace file. The right side of the '!=', '==' operators is list of functions or regexp. to be added to filter separated by space. The '||' operator is used for connecting multiple filter definitions together. It is possible to have more than one '==' and '!=' operators within one filter string. Link: http://lkml.kernel.org/r/1329317514-8131-8-git-send-email-jolsa@redhat.com Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace: Allow to specify filter field type for ftrace eventsJiri Olsa2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding FILTER_TRACE_FN event field type for function tracepoint event, so it can be properly recognized within filtering code. Currently all fields of ftrace subsystem events share the common field type FILTER_OTHER. Since the function trace fields need special care within the filtering code we need to recognize it properly, hence adding the FILTER_TRACE_FN event type. Adding filter parameter to the FTRACE_ENTRY macro, to specify the filter field type for the event. Link: http://lkml.kernel.org/r/1329317514-8131-7-git-send-email-jolsa@redhat.com Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace, perf: Add support to use function tracepoint in perfJiri Olsa2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding perf registration support for the ftrace function event, so it is now possible to register it via perf interface. The perf_event struct statically contains ftrace_ops as a handle for function tracer. The function tracer is registered/unregistered in open/close actions. To be efficient, we enable/disable ftrace_ops each time the traced process is scheduled in/out (via TRACE_REG_PERF_(ADD|DELL) handlers). This way tracing is enabled only when the process is running. Intentionally using this way instead of the event's hw state PERF_HES_STOPPED, which would not disable the ftrace_ops. It is now possible to use function trace within perf commands like: perf record -e ftrace:function ls perf stat -e ftrace:function ls Allowed only for root. Link: http://lkml.kernel.org/r/1329317514-8131-6-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace: Add FTRACE_ENTRY_REG macro to allow event registrationJiri Olsa2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding FTRACE_ENTRY_REG macro so particular ftrace entries could specify registration function and thus become accesible via perf. This will be used in upcomming patch for function trace. Link: http://lkml.kernel.org/r/1329317514-8131-5-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace, perf: Add add/del tracepoint perf registration actionsJiri Olsa2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding TRACE_REG_PERF_ADD and TRACE_REG_PERF_DEL to handle perf event schedule in/out actions. The add action is invoked for when the perf event is scheduled in, while the del action is invoked when the event is scheduled out. Link: http://lkml.kernel.org/r/1329317514-8131-4-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace, perf: Add open/close tracepoint perf registration actionsJiri Olsa2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding TRACE_REG_PERF_OPEN and TRACE_REG_PERF_CLOSE to differentiate register/unregister from open/close actions. The register/unregister actions are invoked for the first/last tracepoint user when opening/closing the event. The open/close actions are invoked for each tracepoint user when opening/closing the event. Link: http://lkml.kernel.org/r/1329317514-8131-3-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace: Add enable/disable ftrace_ops control interfaceJiri Olsa2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding a way to temporarily enable/disable ftrace_ops. The change follows the same way as 'global' ftrace_ops are done. Introducing 2 global ftrace_ops - control_ops and ftrace_control_list which take over all ftrace_ops registered with FTRACE_OPS_FL_CONTROL flag. In addition new per cpu flag called 'disabled' is also added to ftrace_ops to provide the control information for each cpu. When ftrace_ops with FTRACE_OPS_FL_CONTROL is registered, it is set as disabled for all cpus. The ftrace_control_list contains all the registered 'control' ftrace_ops. The control_ops provides function which iterates ftrace_control_list and does the check for 'disabled' flag on current cpu. Adding 3 inline functions: ftrace_function_local_disable/ftrace_function_local_enable - enable/disable the ftrace_ops on current cpu ftrace_function_local_disabled - get disabled ftrace_ops::disabled value for current cpu Link: http://lkml.kernel.org/r/1329317514-8131-2-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | tracing: Don't use p->len field to determine output in __print_*() functionsSteven Rostedt2012-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | If more than one __print_*() function is used in a tracepoint (__print_flags(), __print_symbols(), etc), then the temp seq buffer will not be zero on entry. Using the temp seq buffer's length to know if data has been printed or not in the current function is incorrect and may produce incorrect results. Currently, no in-tree tracepoint causes this bug, but new ones may be created. Cc: Andrew Vagin <avagin@openvz.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | tracing: Don't print an extra separator of flagsAndrey Vagin2012-02-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If __print_flags() is used after another __print_*() function, the temp seq_file buffer will not be empty on entry, and the delimiter will be printed even though there's just one field. We get something like: |S instead of just: S This is because the length of the temp seq buffer is used to determine if the delimiter is printed or not. But this algorithm fails when the seq buffer is not empty on entry, and the delimiter will be printed because it thinks that a previous field was already printed. Link: http://lkml.kernel.org/r/1329650167-480655-1-git-send-email-avagin@openvz.org Signed-off-by: Andrew Vagin <avagin@openvz.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | tracing/trivial: Use kcalloc instead of kzalloc to allocate arrayThomas Meyer2012-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The advantage of kcalloc is, that will prevent integer overflows which could result from the multiplication of number of elements and size and it is also a bit nicer to read. The semantic patch that makes this change is available in https://lkml.org/lkml/2011/11/25/107 Link: http://lkml.kernel.org/r/1322600880.1534.347.camel@localhost.localdomain Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace: sched_switch plugin is deprecatedGeunsik Lim2012-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Actually, sched_switch function tracer is merged into wakeup/wakeup_rt Update 'mini-HOWTO' for ftrace(Kernel function tracer). If we want to trace "sched:sched_switch" to trace sched_switch func, We may utilize event option.(e.g: trace-cmd list -e | grep sched) This patch is based on Linux-3.3.rc2-SMP-PREEMPT Link: http://lkml.kernel.org/r/1328695537-15081-1-git-send-email-geunsik.lim@gmail.com Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Geunsik Lim <geunsik.lim@samsung.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace: Change filter/notrace set functions to return exit codeJiri Olsa2012-02-03
|/ | | | | | | | | | | | | | | | | | | | | | Currently the ftrace_set_filter and ftrace_set_notrace functions do not return any return code. So there's no way for ftrace_ops user to tell wether the filter was correctly applied. The set_ftrace_filter interface returns error in case the filter did not match: # echo krava > set_ftrace_filter bash: echo: write error: Invalid argument Changing both ftrace_set_filter and ftrace_set_notrace functions to return zero if the filter was applied correctly or -E* values in case of error. Link: http://lkml.kernel.org/r/1325495060-6402-2-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2012-01-15
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits) perf tools: Fix compile error on x86_64 Ubuntu perf report: Fix --stdio output alignment when --showcpuutilization used perf annotate: Get rid of field_sep check perf annotate: Fix usage string perf kmem: Fix a memory leak perf kmem: Add missing closedir() calls perf top: Add error message for EMFILE perf test: Change type of '-v' option to INCR perf script: Add missing closedir() calls tracing: Fix compile error when static ftrace is enabled recordmcount: Fix handling of elf64 big-endian objects. perf tools: Add const.h to MANIFEST to make perf-tar-src-pkg work again perf tools: Add support for guest/host-only profiling perf kvm: Do guest-only counting by default perf top: Don't update total_period on process_sample perf hists: Stop using 'self' for struct hist_entry perf hists: Rename total_session to total_period x86: Add counter when debug stack is used with interrupts enabled x86: Allow NMIs to hit breakpoints in i386 x86: Keep current stack in NMI breakpoints ...
| * tracing: Factorize filter creationTejun Heo2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are four places where new filter for a given filter string is created, which involves several different steps. This patch factors those steps into create_[system_]filter() functions which in turn make use of create_filter_{start|finish}() for common parts. The only functional change is that if replace_filter_string() is requested and fails, creation fails without any side effect instead of being ignored. Note that system filter is now installed after the processing is complete which makes freeing before and then restoring filter string on error unncessary. -v2: Rebased to resolve conflict with 49aa29513e and updated both create_filter() functions to always set *filterp instead of requiring the caller to clear it to %NULL on entry. Link: http://lkml.kernel.org/r/1323988305-1469-2-git-send-email-tj@kernel.org Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Have stack tracing set filtered functions at bootSteven Rostedt2011-12-21
| | | | | | | | | | | | | | Add stacktrace_filter= to the kernel command line that lets the user pick specific functions to check the stack on. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Allow access to the boot time function enablingSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | Change set_ftrace_early_filter() to ftrace_set_early_filter() and make it a global function. This will allow other subsystems in the kernel to be able to enable function tracing at start up and reuse the ftrace function parsing code. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Have stack_tracer use a separate list of functionsSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The stack_tracer is used to look at every function and check if the current stack is bigger than the last recorded max stack size. When a new max is found, then it saves that stack off. Currently the stack tracer is limited by the global_ops of the function tracer. As the stack tracer has nothing to do with the ftrace function tracer, except that it uses it as its internal engine, the stack tracer should have its own list. A new file is added to the tracing debugfs directory called: stack_trace_filter that can be used to select which functions you want to check the stack on. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Decouple hash items from showing filtered functionsSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | The set_ftrace_filter shows "hashed" functions, which are functions that are added with operations to them (like traceon and traceoff). As other subsystems may be able to show what functions they are using for function tracing, the hash items should no longer be shown just because the FILTER flag is set. As they have nothing to do with other subsystems filters. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Allow other users of function tracing to use the output listingSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | The function tracer is set up to allow any other subsystem (like perf) to use it. Ftrace already has a way to list what functions are enabled by the global_ops. It would be very helpful to let other users of the function tracer to be able to use the same code. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Create ftrace_hash_empty() helper routineSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are two types of hashes in the ftrace_ops; one type is the filter_hash and the other is the notrace_hash. Either one may be null, meaning it has no elements. But when elements are added, the hash is allocated. Throughout the code, a check needs to be made to see if a hash exists or the hash has elements, but the check if the hash exists is usually missing causing the possible "NULL pointer dereference bug". Add a helper routine called "ftrace_hash_empty()" that returns true if the hash doesn't exist or its count is zero. As they mean the same thing. Last-bug-reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Fix ftrace hash record update with notraceSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When disabling the "notrace" records, that means we want to trace them. If the notrace_hash is zero, it means that we want to trace all records. But to disable a zero notrace_hash means nothing. The check for the notrace_hash count was incorrect with: if (hash && !hash->count) return With the correct comment above it that states that we do nothing if the notrace_hash has zero count. But !hash also means that the notrace hash has zero count. I think this was done to protect against dereferencing NULL. But if !hash is true, then we go through the following loop without doing a single thing. Fix it to: if (!hash || !hash->count) return; Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Use bsearch to find record ipSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that each set of pages in the function list are sorted by ip, we can use bsearch to find a record within each set of pages. This speeds up the ftrace_location() function by magnitudes. For archs (like x86) that need to add a breakpoint at every function that will be converted from a nop to a callback and vice versa, the breakpoint callback needs to know if the breakpoint was for ftrace or not. It requires finding the breakpoint ip within the records. Doing a linear search is extremely inefficient. It is a must to be able to do a fast binary search to find these locations. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Sort the mcount records on each pageSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | Sort records by ip locations of the ftrace mcount calls on each of the set of pages in the function list. This helps in localizing cache usuage when updating the function locations, as well as gives us the ability to quickly find an ip location in the list. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Replace record newlist with record page listSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As new functions come in to be initalized from mcount to nop, they are done by groups of pages. Whether it is the core kernel or a module. There's no need to keep track of these on a per record basis. At startup, and as any module is loaded, the functions to be traced are stored in a group of pages and added to the function list at the end. We just need to keep a pointer to the first page of the list that was added, and use that to know where to start on the list for initializing functions. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Allocate the mcount record pages as groupsSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | Allocate the mcount record pages as a group of pages as big as can be allocated and waste no more than a single page. Grouping the mcount pages as much as possible helps with cache locality, as we do not need to redirect with descriptors as we cross from page to page. It also allows us to do more with the records later on (sort them with bigger benefits). Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Remove usage of "freed" recordsSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | Records that are added to the function trace table are permanently there, except for modules. By separating out the modules to their own pages that can be freed in one shot we can remove the "freed" flag and simplify some of the record management. Another benefit of doing this is that we can also move the records around; sort them. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Allow archs to modify code without stop machineSteven Rostedt2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The stop machine method to modify all functions in the kernel (some 20,000 of them) is the safest way to do so across all archs. But some archs may not need this big hammer approach to modify code on SMP machines, and can simply just update the code it needs. Adding a weak function arch_ftrace_update_code() that now does the stop machine, will also let any arch override this method. If the arch needs to check the system and then decide if it can avoid stop machine, it can still call ftrace_run_stop_machine() to use the old method. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Fix unregister ftrace_ops accountingJiri Olsa2011-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Multiple users of the function tracer can register their functions with the ftrace_ops structure. The accounting within ftrace will update the counter on each function record that is being traced. When the ftrace_ops filtering adds or removes functions, the function records will be updated accordingly if the ftrace_ops is still registered. When a ftrace_ops is removed, the counter of the function records, that the ftrace_ops traces, are decremented. When they reach zero the functions that they represent are modified to stop calling the mcount code. When changes are made, the code is updated via stop_machine() with a command passed to the function to tell it what to do. There is an ENABLE and DISABLE command that tells the called function to enable or disable the functions. But the ENABLE is really a misnomer as it should just update the records, as records that have been enabled and now have a count of zero should be disabled. The DISABLE command is used to disable all functions regardless of their counter values. This is the big off switch and is not the complement of the ENABLE command. To make matters worse, when a ftrace_ops is unregistered and there is another ftrace_ops registered, neither the DISABLE nor the ENABLE command are set when calling into the stop_machine() function and the records will not be updated to match their counter. A command is passed to that function that will update the mcount code to call the registered callback directly if it is the only one left. This means that the ftrace_ops that is still registered will have its callback called by all functions that have been set for it as well as the ftrace_ops that was just unregistered. Here's a way to trigger this bug. Compile the kernel with CONFIG_FUNCTION_PROFILER set and with CONFIG_FUNCTION_GRAPH not set: CONFIG_FUNCTION_PROFILER=y # CONFIG_FUNCTION_GRAPH is not set This will force the function profiler to use the function tracer instead of the function graph tracer. # cd /sys/kernel/debug/tracing # echo schedule > set_ftrace_filter # echo function > current_tracer # cat set_ftrace_filter schedule # cat trace # tracer: nop # # entries-in-buffer/entries-written: 692/68108025 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | kworker/0:2-909 [000] .... 531.235574: schedule <-worker_thread <idle>-0 [001] .N.. 531.235575: schedule <-cpu_idle kworker/0:2-909 [000] .... 531.235597: schedule <-worker_thread sshd-2563 [001] .... 531.235647: schedule <-schedule_hrtimeout_range_clock # echo 1 > function_profile_enabled # echo 0 > function_porfile_enabled # cat set_ftrace_filter schedule # cat trace # tracer: function # # entries-in-buffer/entries-written: 159701/118821262 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | <idle>-0 [002] ...1 604.870655: local_touch_nmi <-cpu_idle <idle>-0 [002] d..1 604.870655: enter_idle <-cpu_idle <idle>-0 [002] d..1 604.870656: atomic_notifier_call_chain <-enter_idle <idle>-0 [002] d..1 604.870656: __atomic_notifier_call_chain <-atomic_notifier_call_chain The same problem could have happened with the trace_probe_ops, but they are modified with the set_frace_filter file which does the update at closure of the file. The simple solution is to change ENABLE to UPDATE and call it every time an ftrace_ops is unregistered. Link: http://lkml.kernel.org/r/1323105776-26961-3-git-send-email-jolsa@redhat.com Cc: stable@vger.kernel.org # 3.0+ Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | Merge branch 'for-linus2' of ↵Linus Torvalds2012-01-08
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs * 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits) reiserfs: Properly display mount options in /proc/mounts vfs: prevent remount read-only if pending removes vfs: count unlinked inodes vfs: protect remounting superblock read-only vfs: keep list of mounts for each superblock vfs: switch ->show_options() to struct dentry * vfs: switch ->show_path() to struct dentry * vfs: switch ->show_devname() to struct dentry * vfs: switch ->show_stats to struct dentry * switch security_path_chmod() to struct path * vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb vfs: trim includes a bit switch mnt_namespace ->root to struct mount vfs: take /proc/*/mounts and friends to fs/proc_namespace.c vfs: opencode mntget() mnt_set_mountpoint() vfs: spread struct mount - remaining argument of next_mnt() vfs: move fsnotify junk to struct mount vfs: move mnt_devname vfs: move mnt_list to struct mount vfs: switch pnode.h macros to struct mount * ...
| * | switch debugfs to umode_tAl Viro2012-01-03
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2012-01-06
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (106 commits) perf kvm: Fix copy & paste error in description perf script: Kill script_spec__delete perf top: Fix a memory leak perf stat: Introduce get_ratio_color() helper perf session: Remove impossible condition check perf tools: Fix feature-bits rework fallout, remove unused variable perf script: Add generic perl handler to process events perf tools: Use for_each_set_bit() to iterate over feature flags perf tools: Unify handling of features when writing feature section perf report: Accept fifos as input file perf tools: Moving code in some files perf tools: Fix out-of-bound access to struct perf_session perf tools: Continue processing header on unknown features perf tools: Improve macros for struct feature_ops perf: builtin-record: Document and check that mmap_pages must be a power of two. perf: builtin-record: Provide advice if mmap'ing fails with EPERM. perf tools: Fix truncated annotation perf script: look up thread using tid instead of pid perf tools: Look up thread names for system wide profiling perf tools: Fix comm for processes with named threads ...
| * | Merge branch 'tip/perf/core' of ↵Ingo Molnar2011-12-06
| |\ \ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core
| | * | tracing: Add entries in buffer and total entries to default output headerSteven Rostedt2011-11-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Knowing the number of event entries in the ring buffer compared to the total number that were written is useful information. The latency format gives this information and there's no reason that the default format does not. This information is now added to the default header, along with the number of online CPUs: # tracer: nop # # entries-in-buffer/entries-written: 159836/64690869 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | <idle>-0 [000] ...2 49.442971: local_touch_nmi <-cpu_idle <idle>-0 [000] d..2 49.442973: enter_idle <-cpu_idle <idle>-0 [000] d..2 49.442974: atomic_notifier_call_chain <-enter_idle <idle>-0 [000] d..2 49.442976: __atomic_notifier_call_chain <-atomic_notifier The above shows that the trace contains 159836 entries, but 64690869 were written. One could figure out that there were 64531033 entries that were dropped. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | tracing: Add irq, preempt-count and need resched info to default trace outputSteven Rostedt2011-11-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | People keep asking how to get the preempt count, irq, and need resched info and we keep telling them to enable the latency format. Some developers think that traces without this info is completely useless, and for a lot of tasks it is useless. The first option was to enable the latency trace as the default format, but the header for the latency format is pretty useless for most tracers and it also does the timestamp in straight microseconds from the time the trace started. This is sometimes more difficult to read as the default trace is seconds from the start of boot up. Latency format: # tracer: nop # # nop latency trace v1.1.5 on 3.2.0-rc1-test+ # -------------------------------------------------------------------- # latency: 0 us, #159771/64234230, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4) # ----------------- # | task: -0 (uid:0 nice:0 policy:0 rt_prio:0) # ----------------- # # _------=> CPU# # / _-----=> irqs-off # | / _----=> need-resched # || / _---=> hardirq/softirq # ||| / _--=> preempt-depth # |||| / delay # cmd pid ||||| time | caller # \ / ||||| \ | / migratio-6 0...2 41778231us+: rcu_note_context_switch <-__schedule migratio-6 0...2 41778233us : trace_rcu_utilization <-rcu_note_context_switch migratio-6 0...2 41778235us+: rcu_sched_qs <-rcu_note_context_switch migratio-6 0d..2 41778236us+: rcu_preempt_qs <-rcu_note_context_switch migratio-6 0...2 41778238us : trace_rcu_utilization <-rcu_note_context_switch migratio-6 0...2 41778239us+: debug_lockdep_rcu_enabled <-__schedule default format: # tracer: nop # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | migration/0-6 [000] 50.025810: rcu_note_context_switch <-__schedule migration/0-6 [000] 50.025812: trace_rcu_utilization <-rcu_note_context_switch migration/0-6 [000] 50.025813: rcu_sched_qs <-rcu_note_context_switch migration/0-6 [000] 50.025815: rcu_preempt_qs <-rcu_note_context_switch migration/0-6 [000] 50.025817: trace_rcu_utilization <-rcu_note_context_switch migration/0-6 [000] 50.025818: debug_lockdep_rcu_enabled <-__schedule migration/0-6 [000] 50.025820: debug_lockdep_rcu_enabled <-__schedule The latency format header has latency information that is pretty meaningless for most tracers. Although some of the header is useful, and we can add that later to the default format as well. What is really useful with the latency format is the irqs-off, need-resched hard/softirq context and the preempt count. This commit adds the option irq-info which is on by default that adds this information: # tracer: nop # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | <idle>-0 [000] d..2 49.309305: cpuidle_get_driver <-cpuidle_idle_call <idle>-0 [000] d..2 49.309307: mwait_idle <-cpu_idle <idle>-0 [000] d..2 49.309309: need_resched <-mwait_idle <idle>-0 [000] d..2 49.309310: test_ti_thread_flag <-need_resched <idle>-0 [000] d..2 49.309312: trace_power_start.constprop.13 <-mwait_idle <idle>-0 [000] d..2 49.309313: trace_cpu_idle <-mwait_idle <idle>-0 [000] d..2 49.309315: need_resched <-mwait_idle If a user wants the old format, they can disable the 'irq-info' option: # tracer: nop # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | <idle>-0 [000] 49.309305: cpuidle_get_driver <-cpuidle_idle_call <idle>-0 [000] 49.309307: mwait_idle <-cpu_idle <idle>-0 [000] 49.309309: need_resched <-mwait_idle <idle>-0 [000] 49.309310: test_ti_thread_flag <-need_resched <idle>-0 [000] 49.309312: trace_power_start.constprop.13 <-mwait_idle <idle>-0 [000] 49.309313: trace_cpu_idle <-mwait_idle <idle>-0 [000] 49.309315: need_resched <-mwait_idle Requested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-23 02:49:39 -0500