BMC/Intel-BMC/linux.git/tools/perf/builtin-top.c, branch dev

perf top: Show backtrace when handling a SIGSEGV on --stdio mode

2015-08-19T18:16:08+00:00

It was just freezing instead of informing about the SEGV, fix it and also print a backtrace, just like in the TUI mode and in 'perf trace'. Tested by provoking a NULL deref when pressing 'z': 0.31% libc-2.20.so [.] malloc_consolidate 0.31% ld-2.20.so [.] _dl_relocate_object 0.28% cc1 [.] ht_lookup 0.28% cc1 [.] ira_init_register_move_cost perf: Segmentation fault Obtained 7 stack frames. perf(dump_stack+0x32) [0x4d69f2] perf(sighandler_dump_stack+0x29) [0x4d6a89] /lib64/libc.so.6(+0x34960) [0x7f5064333960] perf() [0x438790] /lib64/libpthread.so.0(+0x752a) [0x7f50663dd52a] /lib64/libc.so.6(clone+0x6d) [0x7f50643ff22d] # Reported-by: Linus Torvalds Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-pewrpzqd29rgmhu2wkk7fhww@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf top: Move toggling event logic into hists browser

2015-06-22T14:21:11+00:00

Current 'f' key action to enable/disable events won't work if there're more than one event since perf_evsel_menu__run() doesn't return the key. So move it to the hists browser loop so that it can be processed as like other key action, and it's more natural to handle it there IMHO. Signed-off-by: Namhyung Kim Cc: David Ahern Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1434858076-6533-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Configurable per thread proc map processing time out

2015-06-19T21:27:13+00:00

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 top: Tell the user how to unfreeze events after pressing 'f'

2015-06-19T21:13:59+00:00

When the user presses 'f' to disable events the visual cues are, well, the percentages not changing and the number of events freezing. Be more explicit by changing the help line at the bottom of the screen to show the following messages when 'f' is pressed: "Press 'f' again to re-enable the events" And then, when 'f' is pressed again: "Press 'f' to disable the events or 'h' Suggested-by: Ingo Molnar 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-uhiswg9a9rxm5gxg7ptjskjn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf top: Replace CTRL+z with 'f' as hotkey for enable/disable events

2015-06-19T19:56:04+00:00

I.e. 'freeze'/'unfreeze', this is because CTRL+z has a well known action, i.e. suspend the app, perf needs to follow that convention, that will be done on a separate patch, tho. 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-oedcl6ovohara4koig14ayip@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf top: Allow disabling/enabling events dynamicly

2015-06-17T19:50:52+00:00

Now it is possible to press CTRL+z at anytime and that will disable the events being monitored, essentially turning 'top' into 'report', with pressing CTRL+z again making it enable the events again, returning to the 'top' behaviour, i.e. dynamic + decaying of older samples. One may want, for instance, play with: -d, --delay number of seconds to delay between refreshes and: -z, --zero zero history across updates Plus CTRL+z to see only the events since last zeroing, etc. Suggested-by: Ingo Molnar 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-zq7tnh5462blt2yda0bcxh5b@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf hists: Reducing arguments of hist_entry_iter__add()

2015-05-27T15:21:43+00:00

The evsel and sample arguments are to set iter for later use. As it also receives an iter as another argument, just set them before calling the function. Signed-off-by: Namhyung Kim Cc: David Ahern Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1432022650-18205-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'perf/urgent' into perf/core, to resolve conflicts

2015-05-11T09:56:27+00:00

Conflicts: tools/perf/builtin-kmem.c Signed-off-by: Ingo Molnar

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

2015-05-08T19:19:27+00:00

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 top: Fix a segfault when kernel map is restricted.

2015-04-27T16:24:32+00:00

Perf top raise a warning if a kernel sample is collected but kernel map is restricted. The warning message needs to dereference al.map->dso... However, previous perf_event__preprocess_sample() doesn't always guarantee al.map != NULL, for example, when kernel map is restricted. This patch validates al.map before dereferencing, avoid the segfault. Before this patch: $ cat /proc/sys/kernel/kptr_restrict 1 $ perf top -p 120183 perf: Segmentation fault -------- backtrace -------- /path/to/perf[0x509868] /lib64/libc.so.6(+0x3545f)[0x7f9a1540045f] /path/to/perf[0x448820] /path/to/perf(cmd_top+0xe3c)[0x44a5dc] /path/to/perf[0x4766a2] /path/to/perf(main+0x5f5)[0x42e545] /lib64/libc.so.6(__libc_start_main+0xf4)[0x7f9a153ecbd4] /path/to/perf[0x42e674] And gdb call trace: Program received signal SIGSEGV, Segmentation fault. perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0) at builtin-top.c:736 736 !RB_EMPTY_ROOT(&al.map->dso->symbols[MAP__FUNCTION]) ? (gdb) bt #0 perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0) at builtin-top.c:736 #1 perf_top__mmap_read_idx (top=top@entry=0x7fffffffa8a0, idx=idx@entry=0) at builtin-top.c:855 #2 0x000000000044a5dd in perf_top__mmap_read (top=0x7fffffffa8a0) at builtin-top.c:872 #3 __cmd_top (top=0x7fffffffa8a0) at builtin-top.c:997 #4 cmd_top (argc=, argv=, prefix=) at builtin-top.c:1267 #5 0x00000000004766a3 in run_builtin (p=p@entry=0x8a6ce8 , argc=argc@entry=3, argv=argv@entry=0x7fffffffdf70) at perf.c:371 #6 0x000000000042e546 in handle_internal_command (argv=0x7fffffffdf70, argc=3) at perf.c:430 #7 run_argv (argv=0x7fffffffdcf0, argcp=0x7fffffffdcfc) at perf.c:474 #8 main (argc=3, argv=0x7fffffffdf70) at perf.c:589 (gdb) Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Jiri Olsa Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Zefan Li Link: http://lkml.kernel.org/r/1429946703-80807-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo