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* perf inject: Mark a dso if it's usedAndrew Vagin2012-10-261-3/+8
| | | | | | | | | | | | Otherwise they will be not written in an output file. Signed-off-by: Andrew Vagin <avagin@openvz.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1344344165-369636-5-git-send-email-avagin@openvz.org [ committer note: Fixed up wrt changes made in the immediate previous patches ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Merge sched_stat_* and sched_switch eventsAndrew Vagin2012-10-261-3/+139
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | You may want to know where and how long a task is sleeping. A callchain may be found in sched_switch and a time slice in stat_iowait, so I add handler in perf inject for merging this events. My code saves sched_switch event for each process and when it meets stat_iowait, it reports the sched_switch event, because this event contains a correct callchain. By another words it replaces all stat_iowait events on proper sched_switch events. I use the next sequence of commands for testing: perf record -e sched:sched_stat_sleep -e sched:sched_switch \ -e sched:sched_process_exit -g -o ~/perf.data.raw \ ~/test-program perf inject -v -s -i ~/perf.data.raw -o ~/perf.data perf report --stdio -i ~/perf.data 100.00% foo [kernel.kallsyms] [k] __schedule | --- __schedule schedule | |--79.75%-- schedule_hrtimeout_range_clock | schedule_hrtimeout_range | poll_schedule_timeout | do_select | core_sys_select | sys_select | system_call_fastpath | __select | __libc_start_main | --20.25%-- do_nanosleep hrtimer_nanosleep sys_nanosleep system_call_fastpath __GI___libc_nanosleep __libc_start_main And here is test-program.c: #include<unistd.h> #include<time.h> #include<sys/select.h> int main() { struct timespec ts1; struct timeval tv1; int i; long s; for (i = 0; i < 10; i++) { ts1.tv_sec = 0; ts1.tv_nsec = 10000000; nanosleep(&ts1, NULL); tv1.tv_sec = 0; tv1.tv_usec = 40000; select(0, NULL, NULL, NULL,&tv1); } return 1; } Signed-off-by: Andrew Vagin <avagin@openvz.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1344344165-369636-4-git-send-email-avagin@openvz.org [ committer note: Made it use evsel->handler ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Work with filesAndrew Vagin2012-10-261-3/+35
| | | | | | | | | | | | | | | | | Before this patch "perf inject" can only handle data from pipe. I want to use "perf inject" for reworking events. Look at my following patch. v2: add information about new options in tools/perf/Documentation/ Signed-off-by: Andrew Vagin <avagin@openvz.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1344344165-369636-2-git-send-email-avagin@openvz.org [ committer note: fixed it up to cope with 5852a44, 5ded57a, 002439e & f62d3f0 ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf event: No need to create a thread when handling PERF_RECORD_EXITArnaldo Carvalho de Melo2012-10-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we were processing a PERF_RECORD_EXIT event we first used machine__findnew_thread for both the thread exiting and for its parent, only to use just the thread struct associated with the one exiting, and to just delete it. If it existed, i.e. not created at this very moment in machine__findnew_thread, it will be moved to the machine->dead_threads linked list, because we may have hist_entries pointing to it, but if it was created just do be deleted, it will just sit there with no references at all. Use the new machine__find_thread() method so that if it is not there, we don't create it. As a bonus the parent thread will also not be created at this point. Create process_fork() and process_exit() helpers to use this and make the builtins use it instead of the generic process_task(), ditched by this patch. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-z7n2y98ebjyrvmytaope4vdl@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Don't use globals where not needed toArnaldo Carvalho de Melo2012-10-021-7/+6
| | | | | | | | | | | | | | | | | | Some variables were global but used in just one function, so move it to where it belongs. Leftover from patch at the beggining of this series. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-9cer20zhw64wbxyb0zias82i@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Remove static variablesArnaldo Carvalho de Melo2012-10-021-34/+38
| | | | | | | | | | | | | | | | | | | | | We want to reduce the impact that each of the builtins has on perf as a whole, so use the superclassing of perf_tool mechanizm to move its config knobs to the stack, so that only if we use that tool, its impact will be felt. In this case is more about consistency, as the impact of this tool is minimal. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-z2b3matvawihtenmez9hkcja@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Remove unused 'input_name' static varArnaldo Carvalho de Melo2012-10-021-2/+1
| | | | | | | | | | | | | | | | If we ever want to allow inject to work with something other than stdin, we can put it back, but so far it is completely unused, so ditch it. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-qmwpnktckhd43eynnkxgqfpm@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Convert to LIBELF_SUPPORTNamhyung Kim2012-09-291-1/+1
| | | | | | | | | | | | | | | For building perf without libelf, we can set NO_LIBELF=1 as a argument of make. It then defines NO_LIBELF_SUPPORT macro for C code to do the proper handling. However it usually used in a negative semantics - e.g. #ifndef - so we saw double negations which can be misleading. Convert it to a positive form to make it more readable. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1348824728-14025-4-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Use __maybe_used for unused variablesIrina Tirdea2012-09-111-11/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | perf defines both __used and __unused variables to use for marking unused variables. The variable __used is defined to __attribute__((__unused__)), which contradicts the kernel definition to __attribute__((__used__)) for new gcc versions. On Android, __used is also defined in system headers and this leads to warnings like: warning: '__used__' attribute ignored __unused is not defined in the kernel and is not a standard definition. If __unused is included everywhere instead of __used, this leads to conflicts with glibc headers, since glibc has a variables with this name in its headers. The best approach is to use __maybe_unused, the definition used in the kernel for __attribute__((unused)). In this way there is only one definition in perf sources (instead of 2 definitions that point to the same thing: __used and __unused) and it works on both Linux and Android. This patch simply replaces all instances of __used and __unused with __maybe_unused. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1347315303-29906-7-git-send-email-irina.tirdea@intel.com [ committer note: fixed up conflict with a116e05 in builtin-sched.c ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Support minimal build without libelfNamhyung Kim2012-08-091-1/+4
| | | | | | | | | | | | | | | | | | | | Now we have isolated all ELF-specific stuff, it's possible to build without libelf. The output binary can do most of jobs but lacks (user level) symbol information - kernel symbols are still accessable thanks to the kallsyms. To build perf without libelf (elfutils), give NO_LIBELF=1 to make. For now, only 'perf probe' command is removed since it depends on libelf/libdw heavily. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1344228082-15569-4-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Fix broken perf inject -bStephane Eranian2012-05-221-0/+5
| | | | | | | | | | | | | | | | | | | | | perf inject -b was broken. It would not inject any build_id into the stream. Furthermore, it would strip samples from the stream. The reason was a missing initialization of the event attribute structure. The perf_tool.tool.attr() callback was pointing to a simple repipe. But there was no initialization of the internal data structures to keep track of events and event ids. That later caused event id lookups to fail, and sample would get removed. The patch simply adds back the call to perf_event__process_attr() to initialize the evlist structure and now build_ids are again injected. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1337081295-10303-2-git-send-email-eranian@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Rename perf_event_ops to perf_toolArnaldo Carvalho de Melo2011-11-281-27/+28
| | | | | | | | | | | | | | To better reflect that it became the base class for all tools, that must be in each tool struct and where common stuff will be put. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-qgpc4msetqlwr8y2k7537cxe@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Resolve machine earlier and pass it to perf_event_opsArnaldo Carvalho de Melo2011-11-281-32/+38
| | | | | | | | | | | | | | Reducing the exposure of perf_session further, so that we can use the classes in cases where no perf.data file is created. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-stua66dcscsezzrcdugvbmvd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Pass tool context in the the perf_event_ops functionsArnaldo Carvalho de Melo2011-11-281-21/+34
| | | | | | | | | | | | | | | | | | | So that we don't need to have that many globals. Next steps will remove the 'session' pointer, that in most cases is not needed. Then we can rename perf_event_ops to 'perf_tool' that better describes this class hierarchy. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-wp4djox7x6w1i2bab1pt4xxp@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf event: perf_event_ops->attr() manipulates only an evlistArnaldo Carvalho de Melo2011-11-281-1/+7
| | | | | | | | | | | | | | Removing another case where a perf_session is required when processing events. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-ug1wtjbnva4bxwknflkkrlrh@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf session: Pass evsel in event_ops->sample()Arnaldo Carvalho de Melo2011-03-231-1/+10
| | | | | | | | | | | | | | | | | | | | Resolving the sample->id to an evsel since the most advanced tools, report and annotate, and the others will too when they evolve to properly support multi-event perf.data files. Good also because it does an extra validation, checking that the ID is valid when present. When that is not the case, the overhead is just a branch + function call (perf_evlist__id2evsel). Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Kill event_t typedef, use 'union perf_event' insteadArnaldo Carvalho de Melo2011-01-291-39/+43
| | | | | | | | | | | | | | | | And move the event_t methods to the perf_event__ too. No code changes, just namespace consistency. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Rename 'struct sample_data' to 'struct perf_sample'Arnaldo Carvalho de Melo2011-01-291-4/+4
| | | | | | | | | | | | | | Making the namespace more uniform. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf session: Fallback to unordered processing if no sample_id_allIan Munsie2010-12-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we are running the new perf on an old kernel without support for sample_id_all, we should fall back to the old unordered processing of events. If we didn't than we would *always* process events without timestamps out of order, whether or not we hit a reordering race. In other words, instead of there being a chance of not attributing samples correctly, we would guarantee that samples would not be attributed. While processing all events without timestamps before events with timestamps may seem like an intuitive solution, it falls down as PERF_RECORD_EXIT events would also be processed before any samples. Even with a workaround for that case, samples before/after an exec would not be attributed correctly. This patch allows commands to indicate whether they need to fall back to unordered processing, so that commands that do not care about timestamps on every event will not be affected. If we do fallback, this will print out a warning if report -D was invoked. This patch adds the test in perf_session__new so that we only need to test once per session. Commands that do not use an event_ops (such as record and top) can simply pass NULL in it's place. Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <1291951882-sup-6069@au1.ibm.com> Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf session: Parse sample earlierArnaldo Carvalho de Melo2010-12-051-15/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At perf_session__process_event, so that we reduce the number of lines in eache tool sample processing routine that now receives a sample_data pointer already parsed. This will also be useful in the next patch, where we'll allow sample the identity fields in MMAP, FORK, EXIT, etc, when it will be possible to see (cpu, timestamp) just after before every event. Also validate callchains in perf_session__process_event, i.e. as early as possible, and keep a counter of the number of events discarded due to invalid callchains, warning the user about it if it happens. There is an assumption that was kept that all events have the same sample_type, that will be dealt with in the future, when this preexisting limitation will be removed. Tested-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Ian Munsie <imunsie@au1.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <1291318772-30880-4-git-send-email-acme@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Add missing bitsArnaldo Carvalho de Melo2010-05-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | New commands need to have Documentation and be added to command-list.txt so that they can appear when 'perf' is called withouth any subcommand: [root@doppio linux-2.6-tip]# perf usage: perf [--version] [--help] COMMAND [ARGS] The most commonly used perf commands are: annotate Read perf.data (created by perf record) and display annotated code archive Create archive with object files with build-ids found in perf.data file bench General framework for benchmark suites buildid-cache Manage build-id cache. buildid-list List the buildids in a perf.data file diff Read two perf.data files and display the differential profile inject Filter to augment the events stream with additional information kmem Tool to trace/measure kernel memory(slab) properties kvm Tool to trace/measure kvm guest os list List all symbolic event types lock Analyze lock events probe Define new dynamic tracepoints record Run a command and record its profile into perf.data report Read perf.data (created by perf record) and display the profile sched Tool to trace/measure scheduler properties (latencies) stat Run a command and gather performance counter statistics test Runs sanity tests. timechart Tool to visualize total system behavior during a workload top System profiling tool. trace Read perf.data (created by perf record) and display trace output See 'perf help COMMAND' for more information on a specific command. [root@doppio linux-2.6-tip]# The new 'perf inject' command hadn't so it wasn't appearing on that list. Also fix the long option, that should have no spaces in it, rename the faulty one to be '--build-ids', instead of '--inject build-ids'. Reported-by: Ingo Molnar <mingo@elte.hu> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf inject: Refactor read_buildid functionArnaldo Carvalho de Melo2010-05-031-38/+38
| | | | | | | | | | | | | | Into two functions, one that actually reads the build_id for the dso if it wasn't already read, and another taht will inject the event if the build_id is available. Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf: add perf-inject builtinTom Zanussi2010-05-021-0/+228
Currently, perf 'live mode' writes build-ids at the end of the session, which isn't actually useful for processing live mode events. What would be better would be to have the build-ids sent before any of the samples that reference them, which can be done by processing the event stream and retrieving the build-ids on the first hit. Doing that in perf-record itself, however, is off-limits. This patch introduces perf-inject, which does the same job while leaving perf-record untouched. Normal mode perf still records the build-ids at the end of the session as it should, but for live mode, perf-inject can be injected in between the record and report steps e.g.: perf record -o - ./hackbench 10 | perf inject -v -b | perf report -v -i - perf-inject reads a perf-record event stream and repipes it to stdout. At any point the processing code can inject other events into the event stream - in this case build-ids (-b option) are read and injected as needed into the event stream. Build-ids are just the first user of perf-inject - potentially anything that needs userspace processing to augment the trace stream with additional information could make use of this facility. Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frédéric Weisbecker <fweisbec@gmail.com> LKML-Reference: <1272696080-16435-3-git-send-email-tzanussi@gmail.com> Signed-off-by: Tom Zanussi <tzanussi@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>