linux/tools/perf, branch v3.0-rc2

perf top: Don't stop if no kernel symtab is found

2011-05-27T19:02:29Z

We now just warn the user about the fact and go on providing just userspace samples. This fixes a problem when no vmlinux is explicetely passed by the user, thus symbol_conf.vmlinux_name is NULL, no suitable vmlinux is found, and then we get: aldebaran:~> perf top -p 7557 [kernel.kallsyms] with build id 44d9a989eabbd79e486bc079d6b743d397c204e0 not found, continuing without symbols The (null) file can't be used Reported-by: Ingo Molnar Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/n/tip-cj2g81hn64wv2bipmqk4fy2m@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf top: Handle kptr_restrict

2011-05-27T19:02:25Z

Reported-by: Ingo Molnar Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/n/tip-cyl5zmi1nu35vyu7l5im2pyv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf top: Remove unused macro

2011-05-27T19:02:20Z

Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/n/tip-weqbs0tkk2u0qp1xxdxxosfg@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf events: initialize fd array to -1 instead of 0

2011-05-27T19:02:12Z

perf_evsel__alloc_fd allocates an array of file descriptors with the memory initialized to 0. The array has dimensions for cpus and threads. Later, __perf_evsel__open calls sys_perf_event_open for each cpu and thread dimensions. If the open fails for any of the cpus or threads then the fd's for this event are closed and the fd entry in the array is set to -1. Now, if the first attempt fails for the event (e.g., the event is not supported) the remaining dimensions (cpu > 0 and thread > 0) are not touched and left at the initialized value of 0. builtin-stat catches ENOENT and ENOSYS failures and allows the command to continue. The end result is that stat attempts to read from an fd of 0 which of course is stdin and so the command hangs until you type ctrl-D. Resolve by initializing the array to -1 since an fd < 0 is already handled. Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1306511914-8016-1-git-send-email-dsahern@gmail.com Signed-off-by: David Ahern Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Make sure kptr_restrict warnings fit 80 col terms

2011-05-27T19:02:09Z

Suggested-by: Ingo Molnar Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/n/tip-i1p8vrhq7xveyui6t1sc914e@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix build on older systems

2011-05-26T14:16:29Z

Where /usr/include/linux/const.h is not present, e.g. RHEL5. Reported-by: Srikar Dronamraju Cc: Srikar Dronamraju Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/n/tip-ypcw2mu0w7dl1rrc6ncz3pee@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Handle /proc/sys/kernel/kptr_restrict

2011-05-26T14:15:25Z

Perf uses /proc/modules to figure out where kernel modules are loaded. With the advent of kptr_restrict, non root users get zeroes for all module start addresses. So check if kptr_restrict is non zero and don't generate the syntethic PERF_RECORD_MMAP events for them. Warn the user about it in perf record and in perf report. In perf report the reference relocation symbol being zero means that kptr_restrict was set, thus /proc/kallsyms has only zeroed addresses, so don't use it to fixup symbol addresses when using a valid kallsyms (in the buildid cache) or vmlinux (in the vmlinux path) build-id located automatically or specified by the user. Provide an explanation about it in 'perf report' if kernel samples were taken, checking if a suitable vmlinux or kallsyms was found/specified. Restricted /proc/kallsyms don't go to the buildid cache anymore. Example: [acme@emilia ~]$ perf record -F 100000 sleep 1 WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted, check /proc/sys/kernel/kptr_restrict. Samples in kernel functions may not be resolved if a suitable vmlinux file is not found in the buildid cache or in the vmlinux path. Samples in kernel modules won't be resolved at all. If some relocation was applied (e.g. kexec) symbols may be misresolved even with a suitable vmlinux or kallsyms file. [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.005 MB perf.data (~231 samples) ] [acme@emilia ~]$ [acme@emilia ~]$ perf report --stdio Kernel address maps (/proc/{kallsyms,modules}) were restricted, check /proc/sys/kernel/kptr_restrict before running 'perf record'. If some relocation was applied (e.g. kexec) symbols may be misresolved. Samples in kernel modules can't be resolved as well. # Events: 13 cycles # # Overhead Command Shared Object Symbol # ........ ....... ................. ..................... # 20.24% sleep [kernel.kallsyms] [k] page_fault 20.04% sleep [kernel.kallsyms] [k] filemap_fault 19.78% sleep [kernel.kallsyms] [k] __lru_cache_add 19.69% sleep ld-2.12.so [.] memcpy 14.71% sleep [kernel.kallsyms] [k] dput 4.70% sleep [kernel.kallsyms] [k] flush_signal_handlers 0.73% sleep [kernel.kallsyms] [k] perf_event_comm 0.11% sleep [kernel.kallsyms] [k] native_write_msr_safe # # (For a higher level overview, try: perf report --sort comm,dso) # [acme@emilia ~]$ This is because it found a suitable vmlinux (build-id checked) in /lib/modules/2.6.39-rc7+/build/vmlinux (use -v in perf report to see the long file name). If we remove that file from the vmlinux path: [root@emilia ~]# mv /lib/modules/2.6.39-rc7+/build/vmlinux \ /lib/modules/2.6.39-rc7+/build/vmlinux.OFF [acme@emilia ~]$ perf report --stdio [kernel.kallsyms] with build id 57298cdbe0131f6871667ec0eaab4804dcf6f562 not found, continuing without symbols Kernel address maps (/proc/{kallsyms,modules}) were restricted, check /proc/sys/kernel/kptr_restrict before running 'perf record'. As no suitable kallsyms nor vmlinux was found, kernel samples can't be resolved. Samples in kernel modules can't be resolved as well. # Events: 13 cycles # # Overhead Command Shared Object Symbol # ........ ....... ................. ...... # 80.31% sleep [kernel.kallsyms] [k] 0xffffffff8103425a 19.69% sleep ld-2.12.so [.] memcpy # # (For a higher level overview, try: perf report --sort comm,dso) # [acme@emilia ~]$ Reported-by: Stephane Eranian Suggested-by: David Miller Cc: Dave Jones Cc: David Miller Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Kees Cook Cc: Linus Torvalds Cc: Mike Galbraith Cc: Paul Mackerras Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/n/tip-mt512joaxxbhhp1odop04yit@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf: Remove duplicate headers

2011-05-26T11:49:57Z

Signed-off-by: Jesper Juhl Cc: Tom Zanussi Cc: Arnaldo Carvalho de Melo Cc: trivial@kernel.org Cc: Peter Zijlstra Cc: Paul Mackerras Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1105261011290.17400@swampdragon.chaosbits.net Signed-off-by: Ingo Molnar

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2011-05-24T04:20:48Z

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf tools: Fix sample type size calculation in 32 bits archs profile: Use vzalloc() rather than vmalloc() & memset()

perf tools: Fix sample type size calculation in 32 bits archs

2011-05-24T02:33:24Z

The shift used here to count the number of bits set in the mask doesn't work above the low part for archs that are not 64 bits. Fix the constant used for the shift. This fixes a 32-bit perf top failure reported by Eric Dumazet: Can't parse sample, err = -14 Can't parse sample, err = -14 ... Reported-and-tested-by: Eric Dumazet Signed-off-by: Frederic Weisbecker Cc: Linus Torvalds Cc: Steven Rostedt Cc: Eric Dumazet Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Stephane Eranian