kernel/tools/perf/util/machine.h, 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 symbols: Provide libtraceevent callback to resolve kernel symbols

2015-07-24T01:01:37Z

That provides the function signature expected by libtraceevent's pevent_set_function_resolver(). Acked-by: David Ahern Cc: Adrian Hunter Cc: Borislav Petkov Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Cc: Steven Rostedt Link: http://lkml.kernel.org/n/tip-ie6hvlb6u15y4ulg9j1612zg@git.kernel.org 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: Ensure thread-stack is flushed

2015-06-19T19:03:33Z

The thread-stack represents a thread's current stack. When a thread exits there can still be many functions on the stack e.g. exit() can be called many levels deep, so all the callers will never return. To get that information output, the thread-stack must be flushed. Previously it was assumed the thread-stack would be flushed when the struct thread was deleted. With thread ref-counting it is no longer clear when that will be, if ever. So instead explicitly flush all the thread-stacks at the end of a session. Signed-off-by: Adrian Hunter Cc: Jiri Olsa Link: http://lkml.kernel.org/r/1432906425-9911-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Fix up some more method names

2015-06-08T13:31:34Z

Calling the function 'machine__new_module' implies a new 'module' will be allocated, when in fact what is returned is a 'struct map' instance, that not necessarily will be instantiated, as if one already exists with the given module name, it will be returned instead. So be consistent with other "find and if not there, create" like functions, like machine__findnew_thread, machine__findnew_dso, etc, and rename it to machine__findnew_module_map(), that in turn will call machine__findnew_module_dso(). Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/n/tip-acv830vd3hwww2ih5vjtbmu3@git.kernel.org 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 machine: Introduce machine__findnew_dso() method

2015-05-29T15:43:44Z

Similar to machine__findnew_thread(), also prepping for refcounting and locking, this time for struct dso instances. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/n/tip-fv3tshv5o1413coh147lszjc@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf machine: No need to have two DSOs lists

2015-05-29T15:43:43Z

We can, given a DSO, figure out if it is a kernel, a kernel module or a userlevel DSO, so stop having to process two lists in several functions. If searching becomes an issue at some point, we can have them in a rbtree, etc. 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-s4yb0onpdywu6dj2xl9lxi4t@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