user/sven/linux.git/tools/perf/util/thread.c, branch v4.9.2

perf tools: Experiment with cppcheck

2016-10-03T14:24:13Z

Experimenting a bit using cppcheck[1], a static checker brought to my attention by Colin, reducing the scope of some variables, reducing the line of source code lines in the process: $ cppcheck --enable=style tools/perf/util/thread.c Checking tools/perf/util/thread.c... [tools/perf/util/thread.c:17]: (style) The scope of the variable 'leader' can be reduced. [tools/perf/util/thread.c:133]: (style) The scope of the variable 'err' can be reduced. [tools/perf/util/thread.c:273]: (style) The scope of the variable 'err' can be reduced. Will continue later, but these are already useful, keep them. 1: https://sourceforge.net/p/cppcheck/wiki/Home/ Cc: Adrian Hunter Cc: Colin Ian King Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-ixws7lbycihhpmq9cc949ti6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Call unwind__prepare_access for forked thread

2016-07-04T23:27:25Z

Currently we call unwind__prepare_access for map event. In case we report fork event the thread inherits its parent's maps and unwind__prepare_access is never called for the thread. This causes unwind__get_entries seeing uninitialized unwind_libunwind_ops and thus returning no callchain. Adding unwind__prepare_access calls for fork even processing. Signed-off-by: Jiri Olsa Cc: David Ahern Cc: He Kuang Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1467634583-29147-5-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Add initialized arg into unwind__prepare_access

2016-07-04T23:27:12Z

Adding initialized arg into unwind__prepare_access to get feedback about the initialization state. It's not possible to get it from error code, because we return 0 even in case we don't recognize dso, which is valid. The 'initialized' value is used in following patch to speedup unwind__prepare_access calls logic in fork path. Signed-off-by: Jiri Olsa Cc: David Ahern Cc: He Kuang Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1467634583-29147-4-git-send-email-jolsa@kernel.org [ Remove ; after static inline function signatures, fixes build break ] Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Check the target platform before assigning unwind methods

2016-06-07T18:09:36Z

Currently, 'perf script' uses host unwind methods to parse perf.data callchain info without taking the target architecture into account, i.e. assuming the perf.data file was generated on the same machine where the analysis is being performed. So we get wrong result without any warnings when unwinding callchains of x86(32-bit) on x86(64-bit) machine. This patch adds an extra step that checks the target platform before assigning unwind methods. In later patches in this series, we can use this info to assign the right unwind methods for supported platforms. Committer note: After fixing it to register the local unwinder for live mode tools ('perf trace', 'perf top'), i.e. tools that don't use a perf.data file, it works as intended and passes the 'perf test unwind' test: # perf trace -e nanosleep --call dwarf usleep 1 0.328 ( 0.058 ms): usleep/11115 nanosleep(rqtp: 0x7fff083fa480) = 0 __nanosleep_nocancel+0x7 (/usr/lib64/libc-2.22.so) usleep+0x34 (/usr/lib64/libc-2.22.so) main+0x1eb (/usr/bin/usleep) __libc_start_main+0xf0 (/usr/lib64/libc-2.22.so) _start+0x29 (/usr/bin/usleep) # perf test 48 48: Test dwarf unwind : Ok # Signed-off-by: He Kuang Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: David Ahern Cc: Ekaterina Tumanova Cc: Josh Poimboeuf Cc: Kan Liang Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Sukadev Bhattiprolu Cc: Wang Nan Link: http://lkml.kernel.org/r/1464924803-22214-11-git-send-email-hekuang@huawei.com [ Fixed exit path for 'live' mode tools, where we need to default to local unwinding ] Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Move unwind__prepare_access from thread_new into thread__insert_map

2016-06-07T15:08:52Z

To determine the libunwind methods to use, we should get the 32bit/64bit information from maps of a thread. When a thread is newly created, the information is not prepared. This patch moves unwind__prepare_access() into thread__insert_map() so we can get the information we need from maps. Meanwhile, let thread__insert_map() return value and show messages on error. Signed-off-by: He Kuang Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: David Ahern Cc: Ekaterina Tumanova Cc: Josh Poimboeuf Cc: Kan Liang Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Sukadev Bhattiprolu Cc: Wang Nan Link: http://lkml.kernel.org/r/1464924803-22214-5-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf thread: Adopt get_main_thread from db-export.c

2016-05-30T15:41:43Z

Move the get_main_thread function from db-export.c to thread.c so that it can be used elsewhere. Signed-off-by: Andi Kleen Cc: Jiri Olsa Link: http://lkml.kernel.org/r/1464051145-19968-2-git-send-email-andi@firstfloor.org [ Removed leftover bits from db-export.h ] Signed-off-by: Arnaldo Carvalho de Melo

perf thread: Introduce method to set comm from /proc/pid/self

2016-04-26T16:15:00Z

Will be used for lazy comm loading in 'perf trace'. Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Jiri Olsa Cc: Milian Wolff Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-7ogbkuoka1y2qsmcckqxvl5m@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove duplicate const qualifier

2016-04-25T21:12:25Z

Signed-off-by: Eric Engestrom Cc: Adrian Hunter Cc: David Ahern Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1461577678-29517-1-git-send-email-eric.engestrom@imgtec.com Signed-off-by: Arnaldo Carvalho de Melo

perf thread: Fix reference count initial state

2015-12-14T15:08:55Z

We should always return from thread__new(), the constructor, with the object with a reference count of one, so that: struct thread *thread = thread__new(); thread__put(thread); Will call thread__delete(). If any reference is made to that 'thread' variable, it better use thread__get(thread) to hold a reference. We were returning with thread->refcnt set to zero, fix it and some cases where thread__delete() was being called, which were not a problem because just one reference was being used, now that we set it to 1, use thread__put() instead. Reported-by: Masami Hiramatsu Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-4b9mkuk66to4ecckpmpvqx6s@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Avoid deadlock when map_groups are broken

2015-08-19T17:15:09Z

Attempting to clone map groups onto themselves will deadlock. It only happens because of other bugs, but the code should protect itself anyway. Reported-by: Linus Torvalds Signed-off-by: Adrian Hunter Tested-by: Jiri Olsa Link: http://lkml.kernel.org/r/1439994561-27436-2-git-send-email-adrian.hunter@intel.com [ Use pr_debug() instead of dump_fprintf() ] Signed-off-by: Arnaldo Carvalho de Melo