kernel/tools/perf/util/event.c, branch linux-4.3.y

perf tools: Add new PERF_RECORD_SWITCH event

2015-07-24T01:51:13Z

Support processing of PERF_RECORD_SWITCH events and PERF_RECORD_SWITCH_CPU_WIDE events. There is a single tools callback for them both so that the tool must check the event type before using the extra members in PERF_RECORD_SWITCH_CPU_WIDE. There is still no way to select the events, though. That is added in a subsequest patch. Signed-off-by: Adrian Hunter Acked-by: Peter Zijlstra (Intel) Tested-by: Jiri Olsa Cc: Andi Kleen Cc: Mathieu Poirier Cc: Pawel Moll Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1437471846-26995-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf thread_map: Don't access the array entries directly

2015-06-23T21:21:44Z

Instead provide a method to set the array entries, and another to access the contents. Signed-off-by: Jiri Olsa Cc: Adrian Hunter Cc: Andi Kleen Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1435012588-9007-2-git-send-email-jolsa@kernel.org [ Split providing the set/get accessors from transforming the entries structs ] Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Configurable per thread proc map processing time out

2015-06-19T21:27:13Z

The time out to limit the individual proc map processing was hard code to 500ms. This patch introduce a new option --proc-map-timeout to make the time limit configurable. Signed-off-by: Kan Liang Cc: Andi Kleen Cc: David Ahern Cc: Ying Huang Link: http://lkml.kernel.org/r/1434549071-25611-2-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add time out to force stop proc map processing

2015-06-19T21:20:15Z

System wide sampling like 'perf top' or 'perf record -a' read all threads /proc/xxx/maps before sampling. If there are any threads which generating a keeping growing huge maps, perf will do infinite loop during synthesizing. Nothing will be sampled. This patch fixes this issue by adding per-thread timeout to force stop this kind of endless proc map processing. PERF_RECORD_MISC_PROC_MAP_PARSE_TIME_OUT is introduced to indicate that the mmap record are truncated by time out. User will get warning notification when truncated mmap records are detected. Reported-by: Ying Huang Signed-off-by: Kan Liang Cc: Andi Kleen Cc: David Ahern Cc: Ying Huang Link: http://lkml.kernel.org/r/1434549071-25611-1-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: handle PERF_RECORD_LOST_SAMPLES

2015-06-07T14:09:06Z

This patch modifies the perf tool to handle the new RECORD type, PERF_RECORD_LOST_SAMPLES. The number of lost-sample events is stored in .nr_events[PERF_RECORD_LOST_SAMPLES]. The exact number of samples which the kernel dropped is stored in total_lost_samples. When the percentage of dropped samples is greater than 5%, a warning is printed. Here are some examples: Eg 1, Recording different frequently-occurring events is safe with the patch. Only a very low drop rate is associated with such actions. $ perf record -e '{cycles:p,instructions:p}' -c 20003 --no-time ~/tchain ~/tchain $ perf report -D | tail SAMPLE events: 120243 MMAP2 events: 5 LOST_SAMPLES events: 24 FINISHED_ROUND events: 15 cycles:p stats: TOTAL events: 59348 SAMPLE events: 59348 instructions:p stats: TOTAL events: 60895 SAMPLE events: 60895 $ perf report --stdio --group # To display the perf.data header info, please use --header/--header-only options. # # # Total Lost Samples: 24 # # Samples: 120K of event 'anon group { cycles:p, instructions:p }' # Event count (approx.): 24048600000 # # Overhead Command Shared Object Symbol # ................ ........... ................ .................................. # 99.74% 99.86% tchain_edit tchain_edit [.] f3 0.09% 0.02% tchain_edit tchain_edit [.] f2 0.04% 0.00% tchain_edit [kernel.vmlinux] [k] ixgbe_read_reg Eg 2, Recording the same thing multiple times can lead to high drop rate, but it is not a useful configuration. $ perf record -e '{cycles:p,cycles:p}' -c 20003 --no-time ~/tchain Warning: Processed 600592 samples and lost 99.73% samples! [perf record: Woken up 148 times to write data] [perf record: Captured and wrote 36.922 MB perf.data (1206322 samples)] [perf record: Woken up 1 times to write data] [perf record: Captured and wrote 0.121 MB perf.data (1629 samples)] Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: acme@infradead.org Cc: eranian@google.com Link: http://lkml.kernel.org/r/1431285195-14269-9-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar

perf tools: Introduce struct maps

2015-05-27T23:21:41Z

That for now has the maps rbtree and the list for the dead maps, that may be still referenced from some hist_entry, etc. This paves the way for protecting the rbtree with a lock, then refcount the maps and finally remove the removed_maps list, as it'll not ne anymore needed. Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-fl0fa6142pj8khj97fow3uw0@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Use mapsfirst()/mapnext()

2015-05-27T15:21:45Z

In a few more remaining places, for consistency. Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-c2n7slwtto29wndfttdrhfrx@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Protect the machine->threads with a rwlock

2015-05-08T19:19:27Z

In addition to using refcounts for the struct thread lifetime management, we need to protect access to machine->threads from concurrent access. That happens in 'perf top', where a thread processes events, inserting and deleting entries from that rb_tree while another thread decays hist_entries, that end up dropping references and ultimately deleting threads from the rb_tree and releasing its resources when no further hist_entry (or other data structures, like in 'perf sched') references it. So the rule is the same for refcounts + protected trees in the kernel, get the tree lock, find object, bump the refcount, drop the tree lock, return, use object, drop the refcount if no more use of it is needed, keep it if storing it in some other data structure, drop when releasing that data structure. I.e. pair "t = machine__find(new)_thread()" with a "thread__put(t)", and "perf_event__preprocess_sample(&al)" with "addr_location__put(&al)". The addr_location__put() one is because as we return references to several data structures, we may end up adding more reference counting for the other data structures and then we'll drop it at addr_location__put() time. Acked-by: David Ahern Cc: Adrian Hunter Cc: Borislav Petkov Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-bs9rt4n0jw3hi9f3zxyy3xln@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add support for PERF_RECORD_ITRACE_START

2015-05-05T21:12:58Z

Add support for the PERF_RECORD_ITRACE_START event type. This event can be used to determine the pid and tid that are running when Instruction Tracing starts. Generally that information would come from a sched_switch event but, at the start, no sched_switch events may yet have been recorded. Signed-off-by: Adrian Hunter Acked-by: Jiri Olsa Cc: David Ahern Cc: Frederic Weisbecker Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1430404667-10593-8-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add support for PERF_RECORD_AUX

2015-05-05T21:12:57Z

Add support for the PERF_RECORD_AUX event type. PERF_RECORD_AUX is a new kernel event that records when new data lands in the AUX buffer. Currently it is assumed that AUX data follows the same ring buffer conventions used by the perf events buffer, and consequently the AUX event is not processed during recording. It is processed during session processing so that the information in the 'flags' member is made available. The format of PERF_RECORD_AUX is outlined in the linux/perf_events.h header file. The 'flags' are also enumerated. Intel PT and Intel BTS use the flag named PERF_AUX_FLAG_TRUNCATED to determine if data has been lost because the buffer became full as perf was not able to empty it fast enough. Signed-off-by: Adrian Hunter Acked-by: Jiri Olsa Cc: David Ahern Cc: Frederic Weisbecker Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1430404667-10593-7-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo