BMC/Intel-BMC/linux.git/tools/perf/util/dso.h, branch dev

perf tools: Reference count struct dso

2015-06-08T13:31:40+00:00

This has a different model than the 'thread' and 'map' struct lifetimes: there is not a definitive "don't use this DSO anymore" event, i.e. we may get many 'struct map' holding references to the '/usr/lib64/libc-2.20.so' DSO but then at some point some DSO may have no references but we still don't want to straight away release its resources, because "soon" we may get a new 'struct map' that needs it and we want to reuse its symtab or other resources. So we need some way to garbage collect it when crossing some memory usage threshold, which is left for anoter patch, for now it is sufficient to release it when calling dsos__exit(), i.e. when deleting the whole list as part of deleting the 'struct machine' containing it, which will leave only referenced objects being used. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/n/tip-majzgz07cm90t2tejrjy4clf@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Protect accesses the dso rbtrees/lists with a rw lock

2015-06-08T13:31:40+00:00

To allow concurrent access, next step: refcount struct dso instances, so that we can ditch unused them when the last map pointing to it goes away. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/n/tip-yk1k08etpd2aoe3tnrf0oizn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Deal with kernel module names in '[]' correctly

2015-06-03T13:02:38+00:00

Before patch ba92732e9808 ('perf kmaps: Check kmaps to make code more robust'), 'perf report' and 'perf annotate' will segfault if trace data contains kernel module information like this: # perf report -D -i ./perf.data ... 0 0 0x188 [0x50]: PERF_RECORD_MMAP -1/0: [0xffffffbff1018000(0xf068000) @ 0]: x [test_module] ... # perf report -i ./perf.data --objdump=/path/to/objdump --kallsyms=/path/to/kallsyms perf: Segmentation fault -------- backtrace -------- /path/to/perf[0x503478] /lib64/libc.so.6(+0x3545f)[0x7fb201f3745f] /path/to/perf[0x499b56] /path/to/perf(dso__load_kallsyms+0x13c)[0x49b56c] /path/to/perf(dso__load+0x72e)[0x49c21e] /path/to/perf(map__load+0x6e)[0x4ae9ee] /path/to/perf(thread__find_addr_map+0x24c)[0x47deec] /path/to/perf(perf_event__preprocess_sample+0x88)[0x47e238] /path/to/perf[0x43ad02] /path/to/perf[0x4b55bc] /path/to/perf(ordered_events__flush+0xca)[0x4b57ea] /path/to/perf[0x4b1a01] /path/to/perf(perf_session__process_events+0x3be)[0x4b428e] /path/to/perf(cmd_report+0xf11)[0x43bfc1] /path/to/perf[0x474702] /path/to/perf(main+0x5f5)[0x42de95] /lib64/libc.so.6(__libc_start_main+0xf4)[0x7fb201f23bd4] /path/to/perf[0x42dfc4] This is because __kmod_path__parse treats '[' leading names as kernel name instead of names of kernel module. If perf.data contains build information and the buildid of such modules can be found, the dso->kernel of it will be set to DSO_TYPE_KERNEL by __event_process_build_id(), not kernel module. It will then be passed to dso__load() -> dso__load_kernel_sym() -> dso__load_kcore() if --kallsyms is provided. The refered patch adds NULL pointer checker to avoid segfault. However, such kernel modules are still processed incorrectly. This patch fixes __kmod_path__parse, makes it treat names like '[test_module]' as kernel modules. kmod-path.c is also update to reflect the above changes. Signed-off-by: Wang Nan Acked-by: Jiri Olsa Cc: Namhyung Kim Cc: Zefan Li Link: http://lkml.kernel.org/r/1433321541-170245-1-git-send-email-wangnan0@huawei.com [ Fixed the merged with 0443f36b0de0 ("perf machine: Fix the search for the kernel DSO on the unified list" ] Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Adopt findnew_kernel method

2015-05-29T15:43:43+00:00

It never was a 'struct dso' method, so fix that by rename dso__kernel_findnew() to machine__findnew_kernel(). At some point I'll move it all to the machine.[ch] files, for now lets ease patch review by not moving too much stuff. 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-zrxmblgsg5vx0iv4rhvq2f6l@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add dso__data_get/put_fd()

2015-05-27T15:21:44+00:00

Using dso__data_fd() in multi-thread environment is not safe since returned fd can be closed and/or reused anytime. So convert it to the dso__data_get/put_fd() pair to protect the access with lock. The original dso__data_fd() is deprecated and kept only for testing. Signed-off-by: Namhyung Kim Acked-by: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1432137821-10853-3-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Protect dso symbol loading using a mutex

2015-05-18T13:17:36+00:00

Add mutex to protect it from concurrent dso__load(). Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Andi Kleen Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1431909055-21442-26-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add member to struct dso for an instruction cache

2015-04-29T13:37:56+00:00

Add a member to struct dso that can be used by Instruction Trace implementations to hold a cache for decoded instructions. Signed-off-by: Adrian Hunter Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1428594864-29309-16-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Save DSO loading errno to better report errors

2015-03-24T15:08:43+00:00

Before, when some problem happened while trying to load the kernel symtab, 'perf top' would show: ┌─Warning:───────────────────────────┐ │The vmlinux file can't be used. │ │Kernel samples will not be resolved.│ │ │ │ │ │Press any key... │ └────────────────────────────────────┘ Now, it reports: # perf top --vmlinux /dev/null ┌─Warning:───────────────────────────────────────────┐ │The /tmp/passwd file can't be used: Invalid ELF file│ │Kernel samples will not be resolved. │ │ │ │ │ │Press any key... │ └────────────────────────────────────────────────────┘ This is possible because we now register the reason for not being able to load the symtab in the dso->load_errno member, and provide a dso__strerror_load() routine to format this error into a strerror like string with a short reason for the error while loading. That can be just forwarding the dso__strerror_load() call to strerror_r(), or, for a separate errno range providing a custom message. Reported-by: Ingo Molnar Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-u5rb5uq63xqhkfb8uv2lxd5u@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove is_kmodule_extension function

2015-03-23T15:40:15+00:00

Because it's no longer needed. Signed-off-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Corey Ashford Cc: David Ahern Cc: Frederic Weisbecker Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-bb84vlg76t78q8y8fdeed2qn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove compressed argument from is_kernel_module

2015-03-23T15:39:30+00:00

We no longer need the 'compressed' argument, because all current users use 'NULL' for it. Signed-off-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Corey Ashford Cc: David Ahern Cc: Frederic Weisbecker Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-d72q2s7ggbmy2yzhumux4zzw@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo