user/sven/linux.git/tools/perf, branch v4.4

perf list: Robustify event printing routine

2015-12-16T19:43:10Z

When a43eec304259 ("bpf: introduce bpf_perf_event_output() helper") added PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw array that wasn't initialized, thus set to NULL, fix print_symbol_events() to check for that case so that we don't crash if this happens again. (gdb) bt #0 __match_glob (ignore_space=false, pat=, str=) at util/string.c:198 #1 strglobmatch (str=, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252 #2 0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 , max=11, name_only=false, event_glob=0x7fffffffe61d "stall") at util/parse-events.c:1615 #3 print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675 #4 0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=) at builtin-list.c:68 #5 0x00000000004788a5 in run_builtin (p=p@entry=0x871758 , argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370 #6 0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429 #7 run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473 #8 main (argc=2, argv=0x7fffffffe390) at perf.c:588 (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT] $4 = {symbol = 0x0, alias = 0x0} (gdb) A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar Cc: Adrian Hunter Cc: Alexei Starovoitov Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-57wysblcjfrseb0zg5u7ek10@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf list: Add support for PERF_COUNT_SW_BPF_OUT

2015-12-16T19:43:10Z

When PERF_COUNT_SW_BPF_OUTPUT was added to the kernel we should've added it to tools/perf, where it is used just to list events. This ended up causing a segfault in commands like "perf list stall". Fix it by adding that new software counter. A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar Cc: Adrian Hunter Cc: Alexei Starovoitov Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-uya354upi3eprsey6mi5962d@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf hists browser: Fix segfault if use symbol filter in cmdline

2015-12-07T15:02:35Z

If feed perf a symbol filter in cmdline and the result is empty, pressing 'Enter' in the hist browser causes crash: # ./perf report perf.data <-- Common mistake for beginners Then press 'Enter': perf: Segmentation fault -------- backtrace -------- /home/wangnan/perf[0x53e578] /lib64/libc.so.6(+0x3545f)[0x7f76bafe045f] /home/wangnan/perf[0x539dd4] /home/wangnan/perf(perf_evlist__tui_browse_hists+0x96)[0x53d216] /home/wangnan/perf(cmd_report+0x1b9f)[0x442c7f] /home/wangnan/perf[0x47efa2] /home/wangnan/perf(main+0x5f5)[0x432fa5] /lib64/libc.so.6(__libc_start_main+0xf4)[0x7f76bafccbd4] /home/wangnan/perf[0x4330d4] This is because 'perf.data' is interpreted as a symbol filter, and the result is empty, so selection is empty. However, hist_browser__toggle_fold() forgets to check it. This patch simply return false when selection is NULL. Signed-off-by: Wang Nan Acked-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1449455746-41952-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf hists browser: Reset selection when refresh

2015-12-07T15:02:12Z

With the following steps: Step 1: perf report Step 2: Use UP/DOWN to select an entry, don't press 'ENTER' Step 3: Use '/' to filter symbols, use a filter which returns empty result Step 4: Press 'ENTER' We see that, even if we have filtered all the symbols (and the main interface is empty), pressing 'ENTER' still selects one symbol. This behavior surprises the user. This patch resets browser->{he_,}selection in hist_browser__refresh() and lets it choose default selection. In this case browser->{he_,}selection keeps NULL so user won't see annotation item in menu. Signed-off-by: Wang Nan Acked-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1449455746-41952-4-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf hists browser: Add NULL pointer check to prevent crash

2015-12-07T15:02:11Z

Before this patch we can trigger a segfault by following steps: Step 0: Use 'perf record' to generate a perf.data without callchain Step 1: perf report Step 2: Use UP/DOWN to select an entry, don't press 'ENTER' Step 3: Use '/' to filter symbols, use a filter which returns empty result Step 4: Press 'ENTER' (notice here that the old selection is still there. This is another problem) Step 5: Press 'ENTER' to annotate that symbol Step 6: Press 'LEFT' to go out. Result: segfault: perf: Segmentation fault -------- backtrace -------- /home/wangnan/perf[0x53e568] /lib64/libc.so.6(+0x3545f)[0x7fba75d3245f] /home/wangnan/perf[0x537516] /home/wangnan/perf[0x533fef] /home/wangnan/perf[0x53b347] /home/wangnan/perf(perf_evlist__tui_browse_hists+0x96)[0x53d206] /home/wangnan/perf(cmd_report+0x1b9f)[0x442c7f] /home/wangnan/perf[0x47efa2] /home/wangnan/perf(main+0x5f5)[0x432fa5] /lib64/libc.so.6(__libc_start_main+0xf4)[0x7fba75d1ebd4] /home/wangnan/perf[0x4330d4] This is because in this case 'nd' could be NULL in ui_browser__hists_seek(), but that function never checks it. This patch adds checker for potential NULL pointer in that function. After this patch the above steps won't segfault. Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1449455746-41952-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf buildid-list: Fix return value of perf buildid-list -k

2015-12-07T15:02:10Z

The buildid string length is returned by perf buildid-list -k command. Since a non-zero return value means an error, perf buildid-list -k cmd should return 0 when successful instead. Before: # perf buildid-list -k 39356d74e96e02346fe0ec1f3f162b6c522bac62 # echo $? 41 After: # perf buildid-list -k 39356d74e96e02346fe0ec1f3f162b6c522bac62 # echo $? 0 Signed-off-by: Michael Petlan Tested-by: Arnaldo Carvalho de Melo Cc: Masami Hiramatsu Fixes: 0b5a7935f3b5 ("perf buildid: Introduce sysfs/filename__sprintf_build_id") LPU-Reference: 1449080871.24573.145.camel@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf buildid-list: Show running kernel build id fix

2015-12-07T15:02:10Z

The --kernel option of perf buildid-list tool should show the running kernel buildid. The functionality has been lost during other changes of the related code. The build_id__sprintf() function should return length of the build-id string, but it was the length of the build-id raw data instead. Due to that, some return value checking caused that the final string was not printed out. With this patch the build_id__sprintf() returns the correct value, so the --kernel option works again. Before: # perf buildid-list --kernel # After: # perf buildid-list --kernel 972c1edab5bdc06cc224af45d510af662a3c6972 # Signed-off-by: Michael Petlan Cc: Jiri Olsa Cc: Masami Hiramatsu LPU-Reference: 1448632089.24573.114.camel@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Clear probe_trace_event when add_probe_trace_event() fails

2015-11-13T15:28:09Z

When probing with a glob, errors in add_probe_trace_event() won't be passed to debuginfo__find_trace_events() because it would be modified by probe_point_search_cb(). It causes a segfault if perf fails to find an argument for a probe point matched by the glob. For example: # ./perf probe -v -n 'SyS_dup? oldfd' probe-definition(0): SyS_dup? oldfd symbol:SyS_dup? file:(null) line:0 offset:0 return:0 lazy:(null) parsing arg: oldfd into oldfd 1 arguments Looking at the vmlinux_path (7 entries long) Using /lib/modules/4.3.0-rc4+/build/vmlinux for symbols Open Debuginfo file: /lib/modules/4.3.0-rc4+/build/vmlinux Try to find probe point from debuginfo. Matched function: SyS_dup3 found inline addr: 0xffffffff812095c0 Probe point found: SyS_dup3+0 Searching 'oldfd' variable in context. Converting variable oldfd into trace event. oldfd type is long int. found inline addr: 0xffffffff812096d4 Probe point found: SyS_dup2+36 Searching 'oldfd' variable in context. Failed to find 'oldfd' in this function. Matched function: SyS_dup3 Probe point found: SyS_dup3+0 Searching 'oldfd' variable in context. Converting variable oldfd into trace event. oldfd type is long int. Matched function: SyS_dup2 Probe point found: SyS_dup2+0 Searching 'oldfd' variable in context. Converting variable oldfd into trace event. oldfd type is long int. Found 4 probe_trace_events. Opening /sys/kernel/debug/tracing//kprobe_events write=1 Writing event: p:probe/SyS_dup3 _text+2135488 oldfd=%di:s64 Segmentation fault (core dumped) # This patch ensures that add_probe_trace_event() doesn't touches tf->ntevs and tf->tevs if those functions fail. After the patch: # perf probe 'SyS_dup? oldfd' Failed to find 'oldfd' in this function. Added new events: probe:SyS_dup3 (on SyS_dup? with oldfd) probe:SyS_dup3_1 (on SyS_dup? with oldfd) probe:SyS_dup2 (on SyS_dup? with oldfd) You can now use it in all perf tools, such as: perf record -e probe:SyS_dup2 -aR sleep 1 Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Alexei Starovoitov Cc: Masami Hiramatsu Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447417761-156094-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Fix memory leaking on failure by clearing all probe_trace_events

2015-11-13T15:24:32Z

Fix memory leaking on the debuginfo__find_trace_events() failure path which frees an array of probe_trace_events but doesn't clears all the allocated sub-structures and strings. So, before doing zfree(tevs), clear all the array elements which may have allocated resources. Reported-by: Wang Nan Signed-off-by: Masami Hiramatsu Cc: Alexei Starovoitov Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447417761-156094-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf inject: Also re-pipe lost_samples event

2015-11-13T15:23:12Z

perf inject must re-pipe all events otherwise they get dropped from the output file. Signed-off-by: Adrian Hunter Cc: Jiri Olsa Link: http://lkml.kernel.org/r/1447408112-1920-4-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo