aboutsummaryrefslogtreecommitdiffstats
path: root/kernel
Commit message (Collapse)AuthorAge
* Merge branch 'tracing/core' of ↵Ingo Molnar2009-08-26
|\ | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core Conflicts: include/linux/tracepoint.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * tracing: Create generic syscall TRACE_EVENTsJosh Stone2009-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This converts the syscall_enter/exit tracepoints into TRACE_EVENTs, so you can have generic ftrace events that capture all system calls with arguments and return values. These generic events are also renamed to sys_enter/exit, so they're more closely aligned to the specific sys_enter_foo events. Signed-off-by: Josh Stone <jistone@redhat.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> LKML-Reference: <1251150194-1713-5-git-send-email-jistone@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
| * tracing: Move tracepoint callbacks from declaration to definitionJosh Stone2009-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's not strictly correct for the tracepoint reg/unreg callbacks to occur when a client is hooking up, because the actual tracepoint may not be present yet. This happens to be fine for syscall, since that's in the core kernel, but it would cause problems for tracepoints defined in a module that hasn't been loaded yet. It also means the reg/unreg has to be EXPORTed for any modules to use the tracepoint (as in SystemTap). This patch removes DECLARE_TRACE_WITH_CALLBACK, and instead introduces DEFINE_TRACE_FN which stores the callbacks in struct tracepoint. The callbacks are used now when the active state of the tracepoint changes in set_tracepoint & disable_tracepoint. This also introduces TRACE_EVENT_FN, so ftrace events can also provide registration callbacks if needed. Signed-off-by: Josh Stone <jistone@redhat.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> LKML-Reference: <1251150194-1713-4-git-send-email-jistone@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
| * tracing: Make syscall tracepoints conditionalJosh Stone2009-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The syscall enter/exit tracepoints are only supported on archs that HAVE_SYSCALL_TRACEPOINTS, so the declarations should be #ifdef'ed. Also, the definition of syscall_regfunc and syscall_unregfunc should depend on this same config, rather than the ftrace-specific one. Signed-off-by: Josh Stone <jistone@redhat.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> LKML-Reference: <1251150194-1713-3-git-send-email-jistone@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
| * tracing: Rename FTRACE_SYSCALLS for tracepointsJosh Stone2009-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | s/HAVE_FTRACE_SYSCALLS/HAVE_SYSCALL_TRACEPOINTS/g s/TIF_SYSCALL_FTRACE/TIF_SYSCALL_TRACEPOINT/g The syscall enter/exit tracing is no longer specific to just ftrace, so they now have names that reflect their tie to tracepoints instead. Signed-off-by: Josh Stone <jistone@redhat.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> LKML-Reference: <1251150194-1713-2-git-send-email-jistone@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* | ftrace: Move setting of clock-source out of optionsZhaolei2009-08-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are many clock sources for the tracing system but we can only enable/disable one at a time with the trace/options file. We can move the setting of clock-source out of options and add a separate file for it: # cat trace_clock [local] global # echo global > trace_clock # cat trace_clock local [global] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> LKML-Reference: <4A939D08.6050604@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | tracing/filters: Support filtering for char * stringsLi Zefan2009-08-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Usually, char * entries are dangerous in traces because the string can be released whereas a pointer to it can still wait to be read from the ring buffer. But sometimes we can assume it's safe, like in case of RO data (eg: __file__ or __line__, used in bkl trace event). If these RO data are in a module and so is the call to the trace event, then it's safe, because the ring buffer will be flushed once this module get unloaded. To allow char * to be treated as a string: TRACE_EVENT(..., TP_STRUCT__entry( __field_ext(const char *, name, FILTER_PTR_STRING) ... ) ... ); The filtering will not dereference "char *" unless the developer explicitly sets FILTER_PTR_STR in __field_ext. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4A7B9287.90205@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | tracing/filters: Add __field_ext() to TRACE_EVENTLi Zefan2009-08-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add __field_ext(), so a field can be assigned to a specific filter_type, which matches a corresponding filter function. For example, a later patch will allow this: __field_ext(const char *, str, FILTER_PTR_STR); Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4A7B9272.6050709@cn.fujitsu.com> [ Fixed a -1 to FILTER_OTHER Forward ported to latest kernel. ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | tracing/filters: Add filter_type to struct ftrace_event_fieldLi Zefan2009-08-26
|/ | | | | | | | | | | | | | | The type of a field is stored as a string in @type, and here we add @filter_type which is an enum value. This prepares for later patches, so we can specifically assign different @filter_type for the same @type. For example normally a "char *" field is treated as a ptr, but we may want it to be treated as a string when doing filting. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4A7B925E.9030605@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Eliminate code duplication in kernel/tracepoint.cAnirban Sinha2009-08-25
| | | | | | | | Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com> Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> Cc: "Oleg Nesterov" <oleg@tv-sign.ru> LKML-Reference: <DDFD17CC94A9BD49A82147DDF7D545C501EA9047@exchange.ZeugmaSystems.local> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/syscalls: Fix the output of syscalls with no argumentsLi Zefan2009-08-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before: # echo 1 > events/syscalls/sys_enter_sync/enable # cat events/syscalls/sys_enter_sync/format ... field:int nr; offset:12; size:4; print fmt: "# sync # cat trace ... sync-8950 [000] 2366.087670: sys_sync( After: # echo 1 > events/syscalls/sys_enter_sync/enable # cat events/syscalls/sys_enter_sync/format ... field:int nr; offset:12; size:4; print fmt: "" # sync # cat trace sync-2134 [001] 136.780735: sys_sync() Reported-by: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> LKML-Reference: <4A8D05AF.20103@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/syscalls: Add filtering supportLi Zefan2009-08-19
| | | | | | | | | | | | | | | | | | | | | | | Add filtering support for syscall events: # echo 'mode == 0666' > events/syscalls/sys_enter_open # echo 'ret == 0' > events/syscalls/sys_exit_open # echo 1 > events/syscalls/sys_enter_open # echo 1 > events/syscalls/sys_exit_open # cat trace ... modprobe-3084 [001] 117.463140: sys_open(filename: 917d3e8, flags: 0, mode: 1b6) modprobe-3084 [001] 117.463176: sys_open -> 0x0 less-3086 [001] 117.510455: sys_open(filename: 9c6bdb8, flags: 8000, mode: 1b6) sendmail-2574 [001] 122.145840: sys_open(filename: b807a365, flags: 0, mode: 1b6) ... Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A8BAFCB.1040006@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/events: Add trace_define_common_fields()Li Zefan2009-08-19
| | | | | | | | | | | Extract duplicate code. Also prepare for the later patch. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A8BAFB8.1010304@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/events: Add ftrace_event_call param to define_fields()Li Zefan2009-08-19
| | | | | | | | | | | | This parameter is needed by syscall events to add define_fields() handler. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A8BAF90.6060801@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/syscalls: Add fields format for exit eventsLi Zefan2009-08-19
| | | | | | | | | | | | | | | | | | | | | | | | Add "format" file for syscall exit events: # cat events/syscalls/sys_exit_open/format name: sys_exit_open ID: 344 format: field:unsigned short common_type; offset:0; size:2; field:unsigned char common_flags; offset:2; size:1; field:unsigned char common_preempt_count; offset:3; size:1; field:int common_pid; offset:4; size:4; field:int common_tgid; offset:8; size:4; field:int nr; offset:12; size:4; field:unsigned long ret; offset:16; size:4; Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A8BAF61.3060307@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/syscalls: Fix fields format for enter eventsLi Zefan2009-08-19
| | | | | | | | | | | | | | | | | | | | The "format" file of a trace event is originally for parsers to parse ftrace binary output. But the "format" file of a syscall event can only be used by perfcounter, because it describes the format of struct syscall_enter_record not struct syscall_trace_enter. To fix this, we remove struct syscall_enter_record, and then struct syscall_trace_enter will be used by both perf profile and ftrace. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A8BAF39.1030404@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* ftrace: Simplify seqfile codeLi Zefan2009-08-17
| | | | | | | | | | | Use seq_release_private(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4A891AAB.8090701@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* trace_stack: Simplify seqfile codeLi Zefan2009-08-17
| | | | | | | | | | Extract duplicate code in t_start() and t_next(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A891A91.4030602@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* trace_stat: Fix missing entry in stat fileLi Zefan2009-08-17
| | | | | | | | | | | | | | One entry is missing in the output of a stat file. The cause is, when stat_seq_start() is called the 2nd time, we should start from the (pos-1)th elem in the rbtree but not pos, because pos == 0 is the header. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A891A65.70009@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/syscalls: Fix to print parameter typesLi Zefan2009-08-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | When syscall tracing was implemented as a tracer, "syscall_arg_type" trace option could be set to enable the display of syscall parameter types. Now this option is gone since it's no longer a tracer, but the code is still there but dead. So we remove dead code and re-enable the printing of paramete types via the verbose option: # echo verbose > trace_options # echo syscalls > set_event # cat trace ... bash-3331 [000] 95.348937: sys_fcntl64 -> 0x1 bash-3331 [000] 95.348942: sys_close(unsigned int fd: a) ... Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> LKML-Reference: <4A891AF6.5050102@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/events: Add module tracepointsLi Zefan2009-08-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add trace points to trace module_load, module_free, module_get, module_put and module_request, and use trace_event facility to get the trace output. Here's the sample output: TASK-PID CPU# TIMESTAMP FUNCTION | | | | | <...>-42 [000] 1.758380: module_request: fb0 wait=1 call_site=fb_open ... <...>-60 [000] 3.269403: module_load: scsi_wait_scan <...>-60 [000] 3.269432: module_put: scsi_wait_scan call_site=sys_init_module refcnt=0 <...>-61 [001] 3.273168: module_free: scsi_wait_scan ... <...>-1021 [000] 13.836081: module_load: sunrpc <...>-1021 [000] 13.840589: module_put: sunrpc call_site=sys_init_module refcnt=-1 <...>-1027 [000] 13.848098: module_get: sunrpc call_site=try_module_get refcnt=0 <...>-1027 [000] 13.848308: module_get: sunrpc call_site=get_filesystem refcnt=1 <...>-1027 [000] 13.848692: module_put: sunrpc call_site=put_filesystem refcnt=0 ... modprobe-2587 [001] 1088.437213: module_load: trace_events_sample F modprobe-2587 [001] 1088.437786: module_put: trace_events_sample call_site=sys_init_module refcnt=0 Note: - the taints flag can be 'F', 'C' and/or 'P' if mod->taints != 0 - the module refcnt is percpu, so it can be negative in a specific cpu Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Rusty Russell <rusty@rustcorp.com.au> LKML-Reference: <4A891B3C.5030608@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing: Fix syscall tracing on !HAVE_FTRACE_SYSCALLS architecturesIngo Molnar2009-08-13
| | | | | | | | | | | | | The new syscall_regfunc()/unregfunc() functions rely on the existence of TIF_SYSCALL_FTRACE - but that TIF flag is only offered by HAVE_FTRACE_SYSCALLS. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing: Support for syscall events raw records in perfcountersFrederic Weisbecker2009-08-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This bring the support for raw syscall events in perfcounters. The arguments or exit value are saved as a raw sample using the PERF_SAMPLE_RAW attribute in a perf counter. Example (for now you must explicitly set the PERF_SAMPLE_RAW flag in perf record): perf record -e syscalls:sys_enter_open -f -F 1 -a perf report -D 0x2cbb8 [0x50]: event: 9 . . ... raw event: size 80 bytes . 0000: 09 00 00 00 02 00 50 00 20 e9 39 ab 0a 7f 00 00 ......P. .9.... . 0010: bc 14 00 00 bc 14 00 00 01 00 00 00 00 00 00 00 ............... . 0020: 2c 00 00 00 15 01 01 00 bc 14 00 00 bc 14 00 00 ,.............. ^ ^ ^ ^ ^ ^ ^ .......................... Event Size struct trace_entry . 0030: 00 00 00 00 46 98 43 02 00 00 00 00 80 08 00 00 ....F.C........ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ptr to file name open flags . 0040: 00 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 ............... ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ . open mode padding 0x2cbb8 [0x50]: PERF_EVENT_SAMPLE (IP, 2): 5308: 0x7f0aab39e920 period: 1 Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Masami Hiramatsu <mhiramat@redhat.com>
* tracing: Add fields format definition for syscall eventsFrederic Weisbecker2009-08-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Define the format of the syscall trace fields to parse the binary values from a raw trace using the syscall events "format" file. This is defined dynamically using the syscalls metadata. It prepares the export of syscall event raw records to perf counters. Example: $ cat /debug/tracing/events/syscalls/sys_enter_sched_getparam/format name: sys_enter_sched_getparam ID: 39 format: field:unsigned short common_type; offset:0; size:2; field:unsigned char common_flags; offset:2; size:1; field:unsigned char common_preempt_count; offset:3; size:1; field:int common_pid; offset:4; size:4; field:int common_tgid; offset:8; size:4; field:pid_t pid; offset:12; size:8; field:struct sched_param * param; offset:20; size:8; print fmt: "pid: 0x%08lx, param: 0x%08lx", ((unsigned long)(REC->pid)), ((unsigned long)(REC->param)) Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jason Baron <jbaron@redhat.com>
* tracing: Add ftrace event call parameter to its field descriptor handlerFrederic Weisbecker2009-08-11
| | | | | | | | | | | | | | | | | | Add the struct ftrace_event_call as a parameter of its show_format() callback. This way we can use it from the syscall trace events to retrieve the syscall name from the ftrace event call parameter and describe its fields using the syscalls metadata. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jason Baron <jbaron@redhat.com>
* tracing: Add perf counter support for syscalls tracingJason Baron2009-08-11
| | | | | | | | | | | | | | | | | | | | The perf counter support is automated for usual trace events. But we have to define specific callbacks for this to handle syscalls trace events Make 'perf stat -e syscalls:sys_enter_blah' work with syscall style tracepoints. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* tracing: Add individual syscalls tracepoint id supportJason Baron2009-08-11
| | | | | | | | | | | | | | | | | | | The current state of syscalls tracepoints generates only one event id for every syscall events. This patch associates an id with each syscall trace event, so that we can identify each syscall trace event using the 'perf' tool. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* tracing: Add trace events for each syscall entry/exitJason Baron2009-08-11
| | | | | | | | | | | | | | | | | Layer Frederic's syscall tracer on tracepoints. We create trace events via hooking into the SYSCALL_DEFINE macros. This allows us to individually toggle syscall entry and exit points on/off. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* tracing: Add ftrace_event_call void * 'data' fieldJason Baron2009-08-11
| | | | | | | | | | | | | | | | | | | | add an optional void * pointer to 'ftrace_event_call' that is passed in for regfunc and unregfunc. This prepares for syscall tracepoints creation by passing the name of the syscall we want to trace and then retrieve its number through our arch syscall table. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* tracing: Raw_init() bailout in trace event register fail caseJason Baron2009-08-11
| | | | | | | | | | | | | | | | | | | | | | Allow the return value of raw_init() trace event callback to bail us out of creating a trace event file, in case we fail to register our event. Also, we plan to return -ENOSYS for syscall events that don't match any syscalls listed in our arch tracing syscall table, we don't want to warn in that case, we just want this event to be invisible in debugfs and ignored. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* tracing: Add syscall tracepointsJason Baron2009-08-11
| | | | | | | | | | | | | | | | add two tracepoints in syscall exit and entry path, conditioned on TIF_SYSCALL_FTRACE. Supports the syscall trace event code. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* tracing: Call arch_init_ftrace_syscalls at bootJason Baron2009-08-11
| | | | | | | | | | | | | | | | Call arch_init_ftrace_syscalls at boot, so we can determine early the set of syscalls for the syscall trace events. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Jiaying Zhang <jiayingz@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* tracing: Rename set_tracer_flags()'s local variable trace_flagsZhaolei2009-08-11
| | | | | | | | | | | | | | | | set_tracer_flags() have a local variable named trace_flags which has the same name than a global one in the same scope. This leads to confusion, using tracer_flags should be better by its meaning. Changelog: v1->v2: Simplified another patch in this patchset, no change in this patch. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* Merge branch 'linus' into tracing/coreIngo Molnar2009-08-11
|\ | | | | | | | | | | | | | | | | Conflicts: kernel/trace/trace_events_filter.c We use the tracing/core version. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * Merge branch 'perfcounters-fixes-for-linus' of ↵Linus Torvalds2009-08-10
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (27 commits) perf_counter: Zero dead bytes from ftrace raw samples size alignment perf_counter: Subtract the buffer size field from the event record size perf_counter: Require CAP_SYS_ADMIN for raw tracepoint data perf_counter: Correct PERF_SAMPLE_RAW output perf tools: callchain: Fix bad rounding of minimum rate perf_counter tools: Fix libbfd detection for systems with libz dependency perf: "Longum est iter per praecepta, breve et efficax per exempla" perf_counter: Fix a race on perf_counter_ctx perf_counter: Fix tracepoint sampling to be part of generic sampling perf_counter: Work around gcc warning by initializing tracepoint record unconditionally perf tools: callchain: Fix sum of percentages to be 100% by displaying amount of ignored chains in fractal mode perf tools: callchain: Fix 'perf report' display to be callchain by default perf tools: callchain: Fix spurious 'perf report' warnings: ignore empty callchains perf record: Fix the -A UI for empty or non-existent perf.data perf util: Fix do_read() to fail on EOF instead of busy-looping perf list: Fix the output to not include tracepoints without an id perf_counter/powerpc: Fix oops on cpus without perf_counter hardware support perf stat: Fix tool option consistency: rename -S/--scale to -c/--scale perf report: Add debug help for the finding of symbol bugs - show the symtab origin (DSO, build-id, kernel, etc) perf report: Fix per task mult-counter stat reporting ...
| | * perf_counter: Require CAP_SYS_ADMIN for raw tracepoint dataPeter Zijlstra2009-08-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Raw tracepoint data contains various kernel internals and data from other users, so restrict this to CAP_SYS_ADMIN. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1249896452.17467.75.camel@twins> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * perf_counter: Correct PERF_SAMPLE_RAW outputPeter Zijlstra2009-08-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PERF_SAMPLE_* output switches should unconditionally output the correct format, as they are the only way to unambiguously parse the PERF_EVENT_SAMPLE data. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1249896447.17467.74.camel@twins> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * perf_counter: Fix a race on perf_counter_ctxPeter Zijlstra2009-08-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While extending perfcounters with BTS hw-tracing, Markus Metzger managed to trigger this warning: [ 995.557128] WARNING: at kernel/perf_counter.c:1191 __perf_counter_task_sched_out+0x48/0x6b() triggers because commit 9f498cc5be7e013d8d6e4c616980ed0ffc8680d2 (perf_counter: Full task tracing) removed clearing of tsk->perf_counter_ctxp out from under ctx->lock which introduced a race (against perf_lock_task_context). Move it back and deal with the exit notification by explicitly passing along the former task context. Reported-by: Markus T Metzger <markus.t.metzger@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1249667341.17467.5.camel@twins> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * perf_counter: Fix tracepoint sampling to be part of generic samplingFrederic Weisbecker2009-08-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on Peter's comments, make tracepoint sampling generic just like all the other sampling bits are. This is a rename with no code changes: - PERF_SAMPLE_TP_RECORD to PERF_SAMPLE_RAW - struct perf_tracepoint_record to perf_raw_record We want the system in place that transport tracepoints raw samples events into the perf ring buffer to be generalized and usable by any type of counter. Reported-by; Peter Zijlstra <peterz@infradead.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1249698400-5441-4-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * perf_counter: Work around gcc warning by initializing tracepoint record ↵Frederic Weisbecker2009-08-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | unconditionally Despite that the tracepoint record is always present when the PERF_SAMPLE_TP_RECORD flag is set, gcc raises a warning, thinking it might not be initialized: kernel/perf_counter.c: In function ‘perf_counter_output’: kernel/perf_counter.c:2650: warning: ‘tp’ may be used uninitialized in this function Then, initialize it to NULL and always check if it's not NULL before dereference it. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1249698400-5441-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * perf_counter: Fix software counters for fast moving event sourcesPeter Zijlstra2009-08-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reimplement the software counters to deal with fast moving event sources (such as tracepoints). This means being able to generate multiple overflows from a single 'event' as well as support throttling. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | Merge branch 'irq-fixes-for-linus' of ↵Linus Torvalds2009-08-10
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86/irq: Fix move_irq_desc() for nodes without ram
| | * | x86/irq: Fix move_irq_desc() for nodes without ramYinghai Lu2009-08-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't move it if target node is -1. Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <4A785B5D.4070702@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | Merge branch 'timers-fixes-for-linus' of ↵Linus Torvalds2009-08-09
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: posix_cpu_timers_exit_group(): Do not use thread_group_cputimer()
| | * | | posix_cpu_timers_exit_group(): Do not use thread_group_cputimer()Stanislaw Gruszka2009-08-08
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the process exits we don't have to run new cputimer nor use running one (as it not accounts when tsk->exit_state != 0) to get process CPU times. As there is only one thread we can just use CPU times fields from task and signal structs. Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Roland McGrath <roland@redhat.com> Cc: Vitaly Mayatskikh <vmayatsk@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds2009-08-09
| |\ \ \ | | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf_counter: Fix/complete ftrace event records sampling perf_counter, ftrace: Fix perf_counter integration tracing/filters: Always free pred on filter_add_subsystem_pred() failure tracing/filters: Don't use pred on alloc failure ring-buffer: Fix memleak in ring_buffer_free() tracing: Fix recordmcount.pl to handle sections with only weak functions ring-buffer: Fix advance of reader in rb_buffer_peek() tracing: do not use functions starting with .L in recordmcount.pl ring-buffer: do not disable ring buffer on oops_in_progress ring-buffer: fix check of try_to_discard result
| | * | perf_counter: Fix/complete ftrace event records samplingFrederic Weisbecker2009-08-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements the kernel side support for ftrace event record sampling. A new counter sampling attribute is added: PERF_SAMPLE_TP_RECORD which requests ftrace events record sampling. In this case if a PERF_TYPE_TRACEPOINT counter is active and a tracepoint fires, we emit the tracepoint binary record to the perfcounter event buffer, as a sample. Result, after setting PERF_SAMPLE_TP_RECORD attribute from perf record: perf record -f -F 1 -a -e workqueue:workqueue_execution perf report -D 0x21e18 [0x48]: event: 9 . . ... raw event: size 72 bytes . 0000: 09 00 00 00 01 00 48 00 d0 c7 00 81 ff ff ff ff ......H........ . 0010: 0a 00 00 00 0a 00 00 00 21 00 00 00 00 00 00 00 ........!...... . 0020: 2b 00 01 02 0a 00 00 00 0a 00 00 00 65 76 65 6e +...........eve . 0030: 74 73 2f 31 00 00 00 00 00 00 00 00 0a 00 00 00 ts/1........... . 0040: e0 b1 31 81 ff ff ff ff ....... . 0x21e18 [0x48]: PERF_EVENT_SAMPLE (IP, 1): 10: 0xffffffff8100c7d0 period: 33 The raw ftrace binary record starts at offset 0020. Translation: struct trace_entry { type = 0x2b = 43; flags = 1; preempt_count = 2; pid = 0xa = 10; tgid = 0xa = 10; } thread_comm = "events/1" thread_pid = 0xa = 10; func = 0xffffffff8131b1e0 = flush_to_ldisc() What will come next? - Userspace support ('perf trace'), 'flight data recorder' mode for perf trace, etc. - The unconditional copy from the profiling callback brings some costs however if someone wants no such sampling to occur, and needs to be fixed in the future. For that we need to have an instant access to the perf counter attribute. This is a matter of a flag to add in the struct ftrace_event. - Take care of the events recursivity! Don't ever try to record a lock event for example, it seems some locking is used in the profiling fast path and lead to a tracing recursivity. That will be fixed using raw spinlock or recursivity protection. - [...] - Profit! :-) Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Gabriel Munteanu <eduard.munteanu@linux360.ro> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | perf_counter, ftrace: Fix perf_counter integrationPeter Zijlstra2009-08-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds possible second part to the assign argument of TP_EVENT(). TP_perf_assign( __perf_count(foo); __perf_addr(bar); ) Which, when specified make the swcounter increment with @foo instead of the usual 1, and report @bar for PERF_SAMPLE_ADDR (data address associated with the event) when this triggers a counter overflow. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | Merge branch 'linus' into tracing/urgentIngo Molnar2009-08-09
| | |\| | | | | | | | | | | | | | | | | | | | | | | | | Merge reason: Merge up to almost-rc6 to pick up latest perfcounters (on which we'll queue up a dependent fix) Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | tracing/filters: Always free pred on filter_add_subsystem_pred() failureTom Zanussi2009-08-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If filter_add_subsystem_pred() fails due to ENOSPC or ENOMEM, the pred doesn't get freed, while as a side effect it does for other errors. Make it so the caller always frees the pred for any error. Signed-off-by: Tom Zanussi <tzanussi@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <1249746593.6453.32.camel@tropicana> Signed-off-by: Ingo Molnar <mingo@elte.hu>