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* perf report: Add callchain value optionNamhyung Kim2015-11-193-11/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now -g/--call-graph option supports how to display callchain values. Possible values are 'percent', 'period' and 'count'. The percent is same as before and it's the default behavior. The period displays the raw period value rather than the percentage. The count displays the number of occurrences. $ perf report --no-children --stdio -g percent ... 39.93% swapper [kernel.vmlinux] [k] intel_idel | ---intel_idle cpuidle_enter_state cpuidle_enter call_cpuidle cpu_startup_entry | |--28.63%-- start_secondary | --11.30%-- rest_init $ perf report --no-children --show-total-period --stdio -g period ... 39.93% 13018705 swapper [kernel.vmlinux] [k] intel_idel | ---intel_idle cpuidle_enter_state cpuidle_enter call_cpuidle cpu_startup_entry | |--9334403-- start_secondary | --3684302-- rest_init $ perf report --no-children --show-nr-samples --stdio -g count ... 39.93% 80 swapper [kernel.vmlinux] [k] intel_idel | ---intel_idle cpuidle_enter_state cpuidle_enter call_cpuidle cpu_startup_entry | |--57-- start_secondary | --23-- rest_init Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1447047946-1691-6-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf callchain: Add count fields to struct callchain_nodeNamhyung Kim2015-11-192-0/+17
| | | | | | | | | | | | | | | It's to track the count of occurrences of the callchains. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Brendan Gregg <brendan.d.gregg@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1447047946-1691-5-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf callchain: Abstract callchain print functionNamhyung Kim2015-11-192-0/+33
| | | | | | | | | | | | | | | | | This is a preparation to support for printing other type of callchain value like count or period. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1447047946-1691-4-git-send-email-namhyung@kernel.org [ renamed new _sprintf_ operation to _scnprintf_ ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf report: Support folded callchain mode on --stdioNamhyung Kim2015-11-192-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add new call chain option (-g) 'folded' to print callchains in a line. The callchains are separated by semicolons, and preceded by (absolute) percent values and a space. For example, the following 20 lines can be printed in 3 lines with the folded output mode: $ perf report -g flat --no-children | grep -v ^# | head -20 60.48% swapper [kernel.vmlinux] [k] intel_idle 54.60% intel_idle cpuidle_enter_state cpuidle_enter call_cpuidle cpu_startup_entry start_secondary 5.88% intel_idle cpuidle_enter_state cpuidle_enter call_cpuidle cpu_startup_entry rest_init start_kernel x86_64_start_reservations x86_64_start_kernel $ perf report -g folded --no-children | grep -v ^# | head -3 60.48% swapper [kernel.vmlinux] [k] intel_idle 54.60% intel_idle;cpuidle_enter_state;cpuidle_enter;call_cpuidle;cpu_startup_entry;start_secondary 5.88% intel_idle;cpuidle_enter_state;cpuidle_enter;call_cpuidle;cpu_startup_entry;rest_init;start_kernel;x86_64_start_reservations;x86_64_start_kernel This mode is supported only for --stdio now and intended to be used by some scripts like in FlameGraphs[1]. Support for other UI might be added later. [1] http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html Requested-and-Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1447047946-1691-2-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf machine: Fix machine__findnew_module_map to put dsoMasami Hiramatsu2015-11-191-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix machine__findnew_module_map to drop the reference to the dso because it is already referenced by both machine__findnew_module_dso() and map__new2(). Refcnt debugger shows: ==== [1] ==== Unreclaimed dso: 0x1ffd980 Refcount +1 => 1 at ./perf(dso__new+0x1ff) [0x4a62df] ./perf(__dsos__addnew+0x29) [0x4a6e19] ./perf() [0x4b8b91] ./perf(modules__parse+0xfc) [0x4a9d5c] ./perf() [0x4b8460] ./perf(machine__create_kernel_maps+0x150) [0x4bb550] ./perf(machine__new_host+0xfa) [0x4bb75a] ./perf(init_probe_symbol_maps+0x93) [0x506623] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1345a8eaf5] ./perf() [0x4220a9] This map_groups__insert(0x4b8b91) already gets a reference to the new dso: ---- eu-addr2line -e ./perf -f 0x4b8b91 map_groups__insert inlined at util/machine.c:586 in machine__create_module util/map.h:207 ---- So this dso refcnt will be released when map_groups gets released. [snip] Refcount +1 => 2 at ./perf(dso__get+0x34) [0x4a65f4] ./perf() [0x4b8b35] ./perf(modules__parse+0xfc) [0x4a9d5c] ./perf() [0x4b8460] ./perf(machine__create_kernel_maps+0x150) [0x4bb550] ./perf(machine__new_host+0xfa) [0x4bb75a] ./perf(init_probe_symbol_maps+0x93) [0x506623] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1345a8eaf5] ./perf() [0x4220a9] Here, machine__findnew_module_dso(0x4b8b35) gets the dso (and stores it in a local variable): ---- # eu-addr2line -e ./perf -f 0x4b8b35 machine__findnew_module_dso inlined at util/machine.c:578 in machine__create_module util/machine.c:514 ---- Refcount +1 => 3 at ./perf(dso__get+0x34) [0x4a65f4] ./perf(map__new2+0x76) [0x4be1c6] ./perf() [0x4b8b4f] ./perf(modules__parse+0xfc) [0x4a9d5c] ./perf() [0x4b8460] ./perf(machine__create_kernel_maps+0x150) [0x4bb550] ./perf(machine__new_host+0xfa) [0x4bb75a] ./perf(init_probe_symbol_maps+0x93) [0x506623] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1345a8eaf5] ./perf() [0x4220a9] But also map__new2() gets the dso which will be put when the map is released. So, we have to drop the constructor reference obtained in machine__findnew_module_dso(). Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064035.30709.58824.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Fix machine__create_kernel_maps to put kernel dso refcountMasami Hiramatsu2015-11-191-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix machine__create_kernel_maps() to put kernel dso because the dso has been gotten via __machine__create_kernel_maps(). Refcnt debugger shows: ==== [0] ==== Unreclaimed dso: 0x3036ab0 Refcount +1 => 1 at ./perf(dso__new+0x1ff) [0x4a62df] ./perf(__dsos__addnew+0x29) [0x4a6e19] ./perf(dsos__findnew+0xd1) [0x4a7181] ./perf(machine__findnew_kernel+0x27) [0x4a5e17] ./perf() [0x4b8cf2] ./perf(machine__create_kernel_maps+0x28) [0x4bb428] ./perf(machine__new_host+0xfa) [0x4bb74a] ./perf(init_probe_symbol_maps+0x93) [0x506613] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7ffa6809eaf5] ./perf() [0x4220a9] [snip] Refcount +1 => 2 at ./perf(dsos__findnew+0x7e) [0x4a712e] ./perf(machine__findnew_kernel+0x27) [0x4a5e17] ./perf() [0x4b8cf2] ./perf(machine__create_kernel_maps+0x28) [0x4bb428] ./perf(machine__new_host+0xfa) [0x4bb74a] ./perf(init_probe_symbol_maps+0x93) [0x506613] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7ffa6809eaf5] ./perf() [0x4220a9] [snip] Refcount -1 => 1 at ./perf(dso__put+0x2f) [0x4a664f] ./perf(machine__delete+0xfe) [0x4b93ee] ./perf(exit_probe_symbol_maps+0x28) [0x5066b8] ./perf() [0x45628a] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7ffa6809eaf5] ./perf() [0x4220a9] Actually, dsos__findnew gets the dso before returning it, so the dso user (in this case machine__create_kernel_maps) has to put the dso after used. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064033.30709.98954.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Fix __dsos__addnew to put dso after adding it to the listMasami Hiramatsu2015-11-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __dsos__addnew should drop the constructor reference to dso after adding it to the list, because __dsos__add() will get a reference that will be kept while it is in the list. This fixes DSO leaks when entries are removed to the list and the refcount never gets to zero. Refcnt debugger shows: ==== [0] ==== Unreclaimed dso: 0x2fccab0 Refcount +1 => 1 at ./perf(dso__new+0x1ff) [0x4a62df] ./perf(__dsos__addnew+0x29) [0x4a6e19] ./perf(dsos__findnew+0xd1) [0x4a7281] ./perf(machine__findnew_kernel+0x27) [0x4a5e17] ./perf() [0x4b8df2] ./perf(machine__create_kernel_maps+0x28) [0x4bb528] ./perf(machine__new_host+0xfa) [0x4bb84a] ./perf(init_probe_symbol_maps+0x93) [0x506713] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f46df132af5] ./perf() [0x4220a9] Refcount +1 => 2 at ./perf(__dsos__addnew+0xfb) [0x4a6eeb] ./perf(dsos__findnew+0xd1) [0x4a7281] ./perf(machine__findnew_kernel+0x27) [0x4a5e17] ./perf() [0x4b8df2] ./perf(machine__create_kernel_maps+0x28) [0x4bb528] ./perf(machine__new_host+0xfa) [0x4bb84a] ./perf(init_probe_symbol_maps+0x93) [0x506713] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f46df132af5] ./perf() [0x4220a9] Refcount +1 => 3 at ./perf(dsos__findnew+0x7e) [0x4a722e] ./perf(machine__findnew_kernel+0x27) [0x4a5e17] ./perf() [0x4b8df2] ./perf(machine__create_kernel_maps+0x28) [0x4bb528] ./perf(machine__new_host+0xfa) [0x4bb84a] ./perf(init_probe_symbol_maps+0x93) [0x506713] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f46df132af5] ./perf() [0x4220a9] [snip] Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064031.30709.81460.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Fix to put new map after inserting to map_groups in dso__load_symMasami Hiramatsu2015-11-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix dso__load_sym to put the map object which is already insterted to kmaps. Refcnt debugger shows ==== [0] ==== Unreclaimed map: 0x39113e0 Refcount +1 => 1 at ./perf(map__new2+0xb5) [0x4be155] ./perf(dso__load_sym+0xee1) [0x503461] ./perf(dso__load_vmlinux+0xbf) [0x4aa6df] ./perf(dso__load_vmlinux_path+0x8c) [0x4aa83c] ./perf() [0x50528a] ./perf(convert_perf_probe_events+0xd79) [0x50ac29] ./perf() [0x45600f] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f152368baf5] ./perf() [0x4220a9] Refcount +1 => 2 at ./perf(maps__insert+0x9a) [0x4bfffa] ./perf(dso__load_sym+0xf89) [0x503509] ./perf(dso__load_vmlinux+0xbf) [0x4aa6df] ./perf(dso__load_vmlinux_path+0x8c) [0x4aa83c] ./perf() [0x50528a] ./perf(convert_perf_probe_events+0xd79) [0x50ac29] ./perf() [0x45600f] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f152368baf5] ./perf() [0x4220a9] Refcount -1 => 1 at ./perf(map_groups__exit+0x94) [0x4bed04] ./perf(machine__delete+0xb0) [0x4b9300] ./perf(exit_probe_symbol_maps+0x28) [0x506608] ./perf() [0x45628a] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f152368baf5] ./perf() [0x4220a9] This means that the dso__load_sym calls map__new2 and maps_insert, both of them bump the map refcount, but map_groups__exit will drop just one reference. Fix it by dropping the refcount after inserting it into kmaps. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064026.30709.50038.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Make perf_exec_path() always return malloc'd stringMasami Hiramatsu2015-11-193-14/+18
| | | | | | | | | | | | | | | | | | | | | Since system_path() returns malloc'd string if given path is not an absolute path, perf_exec_path() sometimes returns a static string and sometimes returns a malloc'd string depending on the environment variables or command options. This may cause a memory leak because the caller can not unconditionally free the returned string. This fixes perf_exec_path() and system_path() to always return a malloc'd string, so the caller can always free it. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151119060453.14210.65666.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf machine: Fix to destroy kernel maps when machine exitsMasami Hiramatsu2015-11-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Actually machine__exit forgot to call machine__destroy_kernel_maps. This fixes some memory leaks on map as below. Without this fix. ---- ./perf probe vfs_read Added new event: probe:vfs_read (on vfs_read) You can now use it in all perf tools, such as: perf record -e probe:vfs_read -aR sleep 1 REFCNT: BUG: Unreclaimed objects found. REFCNT: Total 4 objects are not reclaimed. To see all backtraces, rerun with -v option ---- With this fix. ---- ./perf probe vfs_read Added new event: probe:vfs_read (on vfs_read) You can now use it in all perf tools, such as: perf record -e probe:vfs_read -aR sleep 1 REFCNT: BUG: Unreclaimed objects found. REFCNT: Total 2 objects are not reclaimed. To see all backtraces, rerun with -v option ---- Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064024.30709.43577.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf machine: Fix machine__destroy_kernel_maps to drop vmlinux_maps referencesMasami Hiramatsu2015-11-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix machine__destroy_kernel_maps() to drop vmlinux_maps references before filling it with NULL. Refcnt debugger shows ==== [1] ==== Unreclaimed map: 0x36b1070 Refcount +1 => 1 at ./perf(map__new2+0xb5) [0x4bdec5] ./perf(machine__create_kernel_maps+0x72) [0x4bb152] ./perf(machine__new_host+0xfa) [0x4bb41a] ./perf(init_probe_symbol_maps+0x93) [0x5062d3] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1fc9fc4af5] ./perf() [0x4220a9] Refcount +1 => 2 at ./perf(maps__insert+0x9a) [0x4bfd6a] ./perf(machine__create_kernel_maps+0xc3) [0x4bb1a3] ./perf(machine__new_host+0xfa) [0x4bb41a] ./perf(init_probe_symbol_maps+0x93) [0x5062d3] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1fc9fc4af5] ./perf() [0x4220a9] Refcount -1 => 1 at ./perf(map_groups__exit+0x94) [0x4bea74] ./perf(machine__delete+0x3d) [0x4b91fd] ./perf(exit_probe_symbol_maps+0x28) [0x506378] ./perf() [0x45628a] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1fc9fc4af5] ./perf() [0x4220a9] map__new2() returns map with refcnt = 1, and also map_groups__insert gets it again in__machine__create_kernel_maps(). machine__destroy_kernel_maps() calls map_groups__remove() to decrement the refcnt, but before decrement it again (corresponding to map__new2), it makes vmlinux_maps[type] = NULL. And this may cause a refcnt leak. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064022.30709.3897.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf machine: Fix machine__findnew_module_map to put registered mapMasami Hiramatsu2015-11-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix machine object to drop the reference to the map object after it inserted it into machine->kmaps. refcnt debugger shows what happened: ---- ==== [2] ==== Unreclaimed map: 0x346f750 Refcount +1 => 1 at ./perf(map__new2+0xb5) [0x4bdea5] ./perf() [0x4b8aaf] ./perf(modules__parse+0xfc) [0x4a9cbc] ./perf() [0x4b83c0] ./perf(machine__create_kernel_maps+0x148) [0x4bb208] ./perf(machine__new_host+0xfa) [0x4bb3fa] ./perf(init_probe_symbol_maps+0x93) [0x5062b3] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5] ./perf() [0x4220a9] Refcount +1 => 2 at ./perf(maps__insert+0x9a) [0x4bfd4a] ./perf() [0x4b8acb] ./perf(modules__parse+0xfc) [0x4a9cbc] ./perf() [0x4b83c0] ./perf(machine__create_kernel_maps+0x148) [0x4bb208] ./perf(machine__new_host+0xfa) [0x4bb3fa] ./perf(init_probe_symbol_maps+0x93) [0x5062b3] ./perf() [0x455ffa] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5] ./perf() [0x4220a9] Refcount -1 => 1 at ./perf(map_groups__exit+0x94) [0x4bea54] ./perf(machine__delete+0x3d) [0x4b91ed] ./perf(exit_probe_symbol_maps+0x28) [0x506358] ./perf() [0x45628a] ./perf(cmd_probe+0x6c) [0x4566bc] ./perf() [0x47abc5] ./perf(main+0x610) [0x421f90] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5] ./perf() [0x4220a9] ---- This pattern clearly shows that the refcnt of the map is acquired twice by map__new2 and maps__insert but released onlu once at map_groups__exit, when we purge its maps rbtree. Since maps__insert already reference counted the map, we have to drop the constructor (map__new2) reference count right after inserting it. These happened in machine__findnew_module_map, as below. ---- # eu-addr2line -e ./perf -f 0x4b8aaf machine__findnew_module_map inlined at util/machine.c:1046 in machine__create_module util/machine.c:582 # eu-addr2line -e ./perf -f 0x4b8acb map_groups__insert inlined at util/machine.c:585 in machine__create_module util/map.h:208 ---- (note that both are at util/machine.c:58X which is machine__findnew_module_map) Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064020.30709.40499.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf probe: Fix to free temporal Dwarf_FrameMasami Hiramatsu2015-11-191-3/+6
| | | | | | | | | | | | | Since dwarf_cfi_addrframe returns malloc'd Dwarf_Frame object, it has to be freed after it is used. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151118064011.30709.65674.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Use same BPF program if arguments are identicalWang Nan2015-11-181-7/+131
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows creating only one BPF program for different 'probe_trace_event'(tev) entries generated by one 'perf_probe_event'(pev) if their prologues are identical. This is done by comparing the argument list of different tev instances, and the maps type of prologue and tev using a mapping array. This patch utilizes qsort to sort the tevs. After sorting, tevs with identical argument lists will be grouped together. Test result: Sample BPF program: #define SEC(NAME) __attribute__((section(NAME), used)) SEC("inlines=no;" "func=SyS_dup? oldfd") int func(void *ctx) { return 1; } It would probe at SyS_dup2 and SyS_dup3, obtaining oldfd as its argument. The following cmdline shows a BPF program being loaded into the kernel by perf: # perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog Before this patch: # perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog [1] 24858 lrwx------ 1 root root 64 Nov 14 04:09 3 -> anon_inode:bpf-prog lrwx------ 1 root root 64 Nov 14 04:09 4 -> anon_inode:bpf-prog ... After this patch: # perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog [1] 25699 lrwx------ 1 root root 64 Nov 14 04:10 3 -> anon_inode:bpf-prog ... Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447749170-175898-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Generate prologue for BPF programsWang Nan2015-11-181-1/+119
| | | | | | | | | | | | | | | | | | | This patch generates a prologue for each 'struct probe_trace_event' for fetching arguments for BPF programs. After bpf__probe(), iterate over each program to check whether prologues are required. If none of the 'struct perf_probe_event' programs will attach to have at least one argument, simply skip preprocessor hooking. For those who a prologue is required, call bpf__gen_prologue() and paste the original instruction after the prologue. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447675815-166222-12-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Add prologue for BPF programs for fetching argumentsHe Kuang2015-11-185-0/+496
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch generates a prologue for a BPF program which fetches arguments for it. With this patch, the program can have arguments as follow: SEC("lock_page=__lock_page page->flags") int lock_page(struct pt_regs *ctx, int err, unsigned long flags) { return 1; } This patch passes at most 3 arguments from r3, r4 and r5. r1 is still the ctx pointer. r2 is used to indicate if dereferencing was done successfully. This patch uses r6 to hold ctx (struct pt_regs) and r7 to hold stack pointer for result. Result of each arguments first store on stack: low address BPF_REG_FP - 24 ARG3 BPF_REG_FP - 16 ARG2 BPF_REG_FP - 8 ARG1 BPF_REG_FP high address Then loaded into r3, r4 and r5. The output prologue for offn(...off2(off1(reg)))) should be: r6 <- r1 // save ctx into a callee saved register r7 <- fp r7 <- r7 - stack_offset // pointer to result slot /* load r3 with the offset in pt_regs of 'reg' */ (r7) <- r3 // make slot valid r3 <- r3 + off1 // prepare to read unsafe pointer r2 <- 8 r1 <- r7 // result put onto stack call probe_read // read unsafe pointer jnei r0, 0, err // error checking r3 <- (r7) // read result r3 <- r3 + off2 // prepare to read unsafe pointer r2 <- 8 r1 <- r7 call probe_read jnei r0, 0, err ... /* load r2, r3, r4 from stack */ goto success err: r2 <- 1 /* load r3, r4, r5 with 0 */ goto usercode success: r2 <- 0 usercode: r1 <- r6 // restore ctx // original user code If all of arguments reside in register (dereferencing is not required), gen_prologue_fastpath() will be used to create fast prologue: r3 <- (r1 + offset of reg1) r4 <- (r1 + offset of reg2) r5 <- (r1 + offset of reg3) r2 <- 0 P.S. eBPF calling convention is defined as: * r0 - return value from in-kernel function, and exit value for eBPF program * r1 - r5 - arguments from eBPF program to in-kernel function * r6 - r9 - callee saved registers that in-kernel function will preserve * r10 - read-only frame pointer to access stack Committer note: At least testing if it builds and loads: # cat test_probe_arg.c struct pt_regs; __attribute__((section("lock_page=__lock_page page->flags"), used)) int func(struct pt_regs *ctx, int err, unsigned long flags) { return 1; } char _license[] __attribute__((section("license"), used)) = "GPL"; int _version __attribute__((section("version"), used)) = 0x40300; # perf record -e ./test_probe_arg.c usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.016 MB perf.data ] # perf evlist perf_bpf_probe:lock_page # Signed-off-by: He Kuang <hekuang@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447675815-166222-11-git-send-email-wangnan0@huawei.com Signed-off-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Allow BPF program config probing optionsWang Nan2015-11-182-4/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By extending the syntax of BPF object section names, this patch allows users to config probing options like what they can do in 'perf probe'. The error message in 'perf probe' is also updated. Test result: For following BPF file test_probe_glob.c: # cat test_probe_glob.c __attribute__((section("inlines=no;func=SyS_dup?"), used)) int func(void *ctx) { return 1; } char _license[] __attribute__((section("license"), used)) = "GPL"; int _version __attribute__((section("version"), used)) = 0x40300; # # ./perf record -e ./test_probe_glob.c ls / ... [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data ] # ./perf evlist perf_bpf_probe:func_1 perf_bpf_probe:func After changing "inlines=no" to "inlines=yes": # ./perf record -e ./test_probe_glob.c ls / ... [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data ] # ./perf evlist perf_bpf_probe:func_3 perf_bpf_probe:func_2 perf_bpf_probe:func_1 perf_bpf_probe:func Then test 'force': Use following program: # cat test_probe_force.c __attribute__((section("func=sys_write"), used)) int funca(void *ctx) { return 1; } __attribute__((section("force=yes;func=sys_write"), used)) int funcb(void *ctx) { return 1; } char _license[] __attribute__((section("license"), used)) = "GPL"; int _version __attribute__((section("version"), used)) = 0x40300; # # perf record -e ./test_probe_force.c usleep 1 Error: event "func" already exists. Hint: Remove existing event by 'perf probe -d' or force duplicates by 'perf probe -f' or set 'force=yes' in BPF source. event syntax error: './test_probe_force.c' \___ Probe point exist. Try 'perf probe -d "*"' and set 'force=yes' (add -v to see detail) ... Then replace 'force=no' to 'force=yes': # vim test_probe_force.c # perf record -e ./test_probe_force.c usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.017 MB perf.data ] # perf evlist perf_bpf_probe:func_1 perf_bpf_probe:func # Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447675815-166222-7-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Allow attaching BPF programs to modules symbolsWang Nan2015-11-181-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By extending the syntax of BPF object section names, this patch allows users to attach BPF programs to symbols in modules. For example: SEC("module=i915;" "parse_cmds=i915_parse_cmds") int parse_cmds(void *ctx) { return 1; } The implementation is very simple: like what 'perf probe' does, for module, fill 'uprobe' field in 'struct perf_probe_event'. Other parts will be done automatically. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447675815-166222-5-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Allow BPF program attach to uprobe eventsWang Nan2015-11-182-6/+115
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a new syntax to the BPF object section name to support probing at uprobe event. Now we can use BPF program like this: SEC( "exec=/lib64/libc.so.6;" "libcwrite=__write" ) int libcwrite(void *ctx) { return 1; } Where, in section name of a program, before the main config string, we can use 'key=value' style options. Now the only option key is "exec", for uprobes. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447675815-166222-4-git-send-email-wangnan0@huawei.com [ Changed the separator from \n to ; ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools: Adopt memdup() from tools/perf, moving it to tools/lib/string.cArnaldo Carvalho de Melo2015-11-183-19/+6
| | | | | | | | | | | | | | That will contain more string functions with counterparts, sometimes verbatim copies, in the kernel. Acked-by: Wang Nan <wangnan0@huawei.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/n/tip-rah6g97kn21vfgmlramorz6o@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf probe: Clear probe_trace_event when add_probe_trace_event() failsWang Nan2015-11-131-6/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> 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 <acme@redhat.com>
* perf probe: Fix memory leaking on failure by clearing all probe_trace_eventsMasami Hiramatsu2015-11-131-1/+3
| | | | | | | | | | | | | | | | | 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 <wangnan0@huawei.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Zefan Li <lizefan@huawei.com> 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 <acme@redhat.com>
* perf buildid-list: Requires ordered eventsAdrian Hunter2015-11-131-0/+1
| | | | | | | | | | | | 'perf buildid-list' processes events to determine hits (i.e. with-hits option). That may not work if events are not sorted in order. i.e. MMAP events must be processed before the samples that depend on them so that sample processing can 'hit' the DSO to which the MMAP refers. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1447408112-1920-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Fix dso lookup by long name and missing buildidsAdrian Hunter2015-11-133-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 4598a0a6d22f ("perf symbols: Improve DSO long names lookup speed with rbtree") Added a tree to lookup dsos by long name. That tree gets corrupted whenever a dso long name is changed because the tree is not updated. One effect of that is buildid-list does not work with the 'with-hits' option because dso lookup fails and results in two structs for the same dso. The first has the buildid but no hits, the second has hits but no buildid. e.g. Before: $ tools/perf/perf record ls arch certs CREDITS Documentation firmware include ipc Kconfig lib Makefile net REPORTING-BUGS scripts sound usr block COPYING crypto drivers fs init Kbuild kernel MAINTAINERS mm README samples security tools virt [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.012 MB perf.data (11 samples) ] $ tools/perf/perf buildid-list 574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms] 30c94dc66a1fe95180c3d68d2b89e576d5ae213c /lib/x86_64-linux-gnu/libc-2.19.so $ tools/perf/perf buildid-list -H 574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms] 0000000000000000000000000000000000000000 /lib/x86_64-linux-gnu/libc-2.19.so After: $ tools/perf/perf buildid-list -H 574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms] 30c94dc66a1fe95180c3d68d2b89e576d5ae213c /lib/x86_64-linux-gnu/libc-2.19.so The fix is to record the root of the tree on the dso so that dso__set_long_name() can update the tree when the long name changes. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Douglas Hatch <doug.hatch@hp.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Scott J Norton <scott.norton@hp.com> Cc: Waiman Long <Waiman.Long@hp.com> Fixes: 4598a0a6d22f ("perf symbols: Improve DSO long names lookup speed with rbtree") Link: http://lkml.kernel.org/r/1447408112-1920-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Allow forcing reading of non-root owned files by rootArnaldo Carvalho de Melo2015-11-122-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | When the root user tries to read a file owned by some other user we get: # ls -la perf.data -rw-------. 1 acme acme 20032 Nov 12 15:50 perf.data # perf report File perf.data not owned by current user or root (use -f to override) # perf report -f | grep -v ^# | head -2 30.96% ls [kernel.vmlinux] [k] do_set_pte 28.24% ls libc-2.20.so [.] intel_check_word # That wasn't happening when the symbol code tried to read a JIT map, where the same check was done but no forcing was possible, fix it. Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com> Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2380 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Rebuild rbtree when adjusting symbols for kcoreAdrian Hunter2015-11-121-16/+14
| | | | | | | | | | | | | | | | | | | | | | | | | Normally symbols are read from the DSO and adjusted, if need be, so that the symbol start matches the file offset in the DSO file (we want the file offset because that is what we know from MMAP events). That is done by dso__load_sym() which inserts the symbols *after* adjusting them. In the case of kcore, the symbols have been read from kallsyms and the symbol start is the memory address. The symbols have to be adjusted to match the kcore file offsets. dso__split_kallsyms_for_kcore() does that, but now the adjustment is being done *after* the symbols have been inserted. It appears dso__split_kallsyms_for_kcore() was assuming that changing the symbol start would not change the order in the rbtree - which is, of course, not guaranteed. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/563CB241.2090701@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf probe: Verify parameters in two functionsWang Nan2015-11-111-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | On kernel with only one out of CONFIG_KPROBE_EVENTS and CONFIG_UPROBE_EVENTS enabled, 'perf probe -d' causes a segfault because perf_del_probe_events() calls probe_file__get_events() with a negative fd. This patch fixes it by adding parameter validation at the entry of probe_file__get_events() and probe_file__get_rawlist(). Since they are both non-static public functions (in .h file), parameter verifying is required. v1 -> v2: Verify fd at the head of probe_file__get_rawlist() instead of checking at call site (suggested by Masami and Arnaldo at [1,2]). [1] http://lkml.kernel.org/r/50399556C9727B4D88A595C8584AAB37526048E3@GSjpTKYDCembx32.service.hitachi.net [2] http://lkml.kernel.org/r/20151105155830.GV13236@kernel.org Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446803415-83382-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf session: Add missing newlines to some pr_err() callsArnaldo Carvalho de Melo2015-11-111-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | Before: [acme@zoo linux]$ perf evlist WARNING: The perf.data file's data size field is 0 which is unexpected. Was the 'perf record' command properly terminated? non matching sample_type[acme@zoo linux]$ After: [acme@zoo linux]$ perf evlist WARNING: The perf.data file's data size field is 0 which is unexpected. Was the 'perf record' command properly terminated? non matching sample_type [acme@zoo linux]$ Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-wscok3a2s7yrj8156oc2r6qe@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf annotate: Support full source file paths for srcline fixMichael Petlan2015-11-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The --full-paths option did not show the full source file paths in the 'perf annotate' tool, because the value of the option was not propagated into the related functions. With this patch the value of the --full-paths option is known to the function that composes the srcline string, so it prints the full path when necessary. Committer Note: This affects annotate when the --print-line option is used: # perf annotate -h 2>&1 | grep print-line -l, --print-line print matching source lines (may be slow) Looking just at the lines that should be affected by this change: Before: # perf annotate --print-line --full-paths --stdio fput | grep '\.[ch]:[0-9]\+' 94.44 atomic64_64.h:114 5.56 file_table.c:265 file_table.c:265 5.56 : ffffffff81219a00: callq ffffffff81769360 <__fentry__> atomic64_64.h:114 94.44 : ffffffff81219a05: lock decq 0x38(%rdi) After: # perf annotate --print-line --full-paths --stdio fput | grep '\.[ch]:[0-9]\+' 94.44 /home/git/linux/arch/x86/include/asm/atomic64_64.h:114 5.56 /home/git/linux/fs/file_table.c:265 /home/git/linux/fs/file_table.c:265 5.56 : ffffffff81219a00: callq ffffffff81769360 <__fentry__> /home/git/linux/arch/x86/include/asm/atomic64_64.h:114 94.44 : ffffffff81219a05: lock decq 0x38(%rdi) # Signed-off-by: Michael Petlan <mpetlan@redhat.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2365 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf test: Add 'perf test BPF'Wang Nan2015-11-062-1/+33
| | | | | | | | | | | | | | | | | | | | This patch adds BPF testcase for testing BPF event filtering. By utilizing the result of 'perf test LLVM', this patch compiles the eBPF sample program then test its ability. The BPF script in 'perf test LLVM' lets only 50% samples generated by epoll_pwait() to be captured. This patch runs that system call for 111 times, so the result should contain 56 samples. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Improve BPF related error messagesWang Nan2015-11-064-15/+108
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A series of bpf loader related error codes were introduced to help error reporting. Functions were improved to return these new error codes. Functions which return pointers were adjusted to encode error codes into return value using the ERR_PTR() interface. bpf_loader_strerror() was improved to convert these error messages to strings. It checks the error codes and calls libbpf_strerror() and strerror_r() accordingly, so caller don't need to consider checking the range of the error code. In bpf__strerror_load(), print kernel version of running kernel and the object's 'version' section to notify user how to fix his/her program. v1 -> v2: Use macro for error code. Fetch error message based on array index, eliminate for-loop. Print version strings. Before: # perf record -e ./test_kversion_nomatch_program.o sleep 1 event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP After: # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ 'version' (4.4.0) doesn't match running kernel (4.3.0) SKIP Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446818289-87444-1-git-send-email-wangnan0@huawei.com [ Add 'static inline' to bpf__strerror_prepare_load() when LIBBPF is disabled ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Make fetch_kernel_version() publicly availableWang Nan2015-11-063-33/+49
| | | | | | | | | | | | | | | There are 2 places in llvm-utils.c which find kernel version information through uname. This patch extracts the uname related code into a fetch_kernel_version() function and puts it into util.h so it can be reused. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446818135-87310-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* bpf tools: Improve libbpf error reportingWang Nan2015-11-062-9/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In this patch, a series of libbpf specific error numbers and libbpf_strerror() are introduced to help reporting errors. Functions are updated to pass correct the error number through the CHECK_ERR() macro. All users of bpf_object__open{_buffer}() and bpf_program__title() in perf are modified accordingly. In addition, due to the error codes changing, bpf__strerror_load() is also modified to use them. bpf__strerror_head() is also changed accordingly so it can parse libbpf errors. bpf_loader_strerror() is introduced for that purpose, and will be improved by the following patch. load_program() is improved not to dump log buffer if it is empty. log buffer is also used to deduce whether the error was caused by an invalid program or other problem. v1 -> v2: - Using macro for error code. - Fetch error message based on array index, eliminate for-loop. - Use log buffer to detect the reason of failure. 3 new error code are introduced to replace LIBBPF_ERRNO__LOAD. In v1: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_big_program.o ls event syntax error: './test_big_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP In v2: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Kernel verifier blocks program loading SKIP # perf record -e ./test_kversion_nomatch_program.o event syntax error: './test_kversion_nomatch_program.o' \___ Incorrect kernel version SKIP (Will be further improved by following patches) # perf record -e ./test_big_program.o event syntax error: './test_big_program.o' \___ Program too big SKIP Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf probe: Cleanup find_perf_probe_point_from_map to reduce redundancyMasami Hiramatsu2015-11-061-5/+2
| | | | | | | | | | | | | | | | | | | In find_perf_probe_point_from_map(), the 'ret' variable is initialized with -ENOENT but overwritten by the return code of kernel_get_symbol_address_by_name(), and after that it is re-initialized with -ENOENT again. Setting ret=-ENOENT twice looks a bit redundant. This avoids the overwriting and just returns -ENOENT if some error happens to simplify the code. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-ufp1zgbktzmttcputozneomd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf annotate: Inform the user about objdump failures in --stdioAndi Kleen2015-11-061-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the browser fails to annotate it is difficult for users to find out what went wrong. Add some errors for objdump failures that are displayed in the UI. Note it would be even better to handle these errors smarter, like falling back to the binary when the debug info is somehow corrupted. But for now just giving a better error is an improvement. Committer note: This works for --stdio, where errors just scroll by the screen: # perf annotate --stdio intel_idle Failure running objdump --start-address=0xffffffff81418290 --stop-address=0xffffffff814183ae -l -d --no-show-raw -S -C /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1 2>/dev/null|grep -v /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1|expand Percent | Source code & Disassembly of vmlinux for cycles:pp ------------------------------------------------------------------ And with that one can use that command line to try to find out more about what happened instead of getting a blank screen, an improvement. We need tho to improve this further to get it to work with other UIs, like --tui and --gtk, where it continues showing a blank screen, no messages, as the pr_err() used is enough just for --stdio. Signed-off-by: Andi Kleen <ak@linux.intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1446779167-18949-1-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Fix find_perf_probe_point_from_map() which incorrectly returns ↵Wang Nan2015-11-051-0/+3
| | | | | | | | | | | | | | | | | | | | | success It is possible that find_perf_probe_point_from_map() fails to find a symbol but still returns 0 because of an small error when coding: find_perf_probe_point_from_map() set 'ret' to error code at first, but also use it to hold return value of kernel_get_symbol_address_by_name(). This patch resets 'ret' to error even kernel_get_symbol_address_by_name() success, so if !sym, the whole function returns error correctly. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446729565-27592-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf llvm: Pass LINUX_VERSION_CODE to BPF program when compilingWang Nan2015-11-051-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Arnaldo suggests to make LINUX_VERSION_CODE works like __func__ and __FILE__ so user don't need to care setting right linux version too much. In this patch, perf llvm transfers LINUX_VERSION_CODE macro through clang cmdline. [1] http://lkml.kernel.org/r/20151029223744.GK2923@kernel.org Committer notes: Before, forgetting to update the version: # uname -r 4.3.0-rc1+ # cat bpf.c __attribute__((section("fork=_do_fork"), used)) int fork(void *ctx) { return 1; } char _license[] __attribute__((section("license"), used)) = "GPL"; int _version __attribute__((section("version"), used)) = 0x40200; # # perf record -e bpf.c sleep 1 event syntax error: 'bpf.c' \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel? (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events # After: # grep version bpf.c int _version __attribute__((section("version"), used)) = LINUX_VERSION_CODE; # perf record -e bpf.c sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.017 MB perf.data ] # perf evlist -v perf_bpf_probe:fork: type: 2, size: 112, config: 0x5ee, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 # Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446636007-239722-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf llvm: Pass number of configured CPUs to clang compilerWang Nan2015-11-051-6/+18
| | | | | | | | | | | | | | | | | | | | | | This patch introduces a new macro "__NR_CPUS__" to perf's embedded clang compiler, which represent the number of configured CPUs in this system. BPF programs can use this macro to create a map with the same number of system CPUs. For example: struct bpf_map_def SEC("maps") pmu_map = { .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY, .key_size = sizeof(int), .value_size = sizeof(u32), .max_entries = __NR_CPUS__, }; Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446636007-239722-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Insert split maps correctly into origin groupJiri Olsa2015-11-051-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When new maps are cloned out of split map they are added into origin map's group, but their groups pointer is not updated. This could lead to a segfault, because map->groups is expected to be always set as reported by Markus: __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238 238 return __machine__kernel_map(map->groups->machine, map->type) = (gdb) bt #0 __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238 #1 0x00000000004393e4 in symbol_filter (map=map@entry=0x1abb7a0, sym=sym@entry #2 0x00000000004fcd4d in dso__load_sym (dso=dso@entry=0x166dae0, map=map@entry #3 0x00000000004a64e0 in dso__load (dso=0x166dae0, map=map@entry=0x1abb7a0, fi #4 0x00000000004b941f in map__load (filter=0x4393c0 <symbol_filter>, map=<opti #5 map__find_symbol (map=0x1abb7a0, addr=40188, filter=0x4393c0 <symbol_filter ... Adding __map_groups__insert function to add map into groups together with map->groups pointer update. It takes no lock as opposed to existing map_groups__insert, as maps__fixup_overlappings(), where it is being called, already has the necessary lock held. Using __map_groups__insert to add new maps after map split. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20151104140811.GA32664@krava.brq.redhat.com Fixes: cfc5acd4c80b ("perf top: Filter symbols based on __map__is_kernel(map)") Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Move sw clock metrics printout to stat-shadowAndi Kleen2015-11-041-0/+5
| | | | | | | | | | | | The sw clock metrics printing was missed in the earlier move to stat-shadow of all the other metric printouts. Move it too. v2: Fix metrics printing in this version to make bisect safe. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/1446515428-7450-2-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Mute libbpf when '-v' not setWang Nan2015-11-031-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to [1], libbpf should be muted. This patch reset info and warning message level to ensure libbpf doesn't output anything even if error happened. [1] http://lkml.kernel.org/r/20151020151255.GF5119@kernel.org Committer note: Before: Testing it with an incompatible kernel version in the .c file that generated foo.o: [root@zoo ~]# perf record -e /tmp/foo.o sleep 1 libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: libbpf: -- END LOG -- libbpf: failed to load program 'fork=_do_fork' libbpf: failed to load object '/tmp/foo.o' event syntax error: '/tmp/foo.o' \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel? (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events [root@zoo ~]# After: [root@zoo ~]# perf record -e /tmp/foo.o sleep 1 event syntax error: '/tmp/foo.o' \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel? (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events [root@zoo ~]# This, BTW, need fixing to emit a proper message by validating the version in the foo.o "version" ELF section against the running kernel, warning the user instead of asking the kernel to load a binary that it will refuse due to unmatching kernel version. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446547486-229499-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf unwind: Pass symbol source to libunwindRabin Vincent2015-10-291-1/+4
| | | | | | | | | | | | | | | Even if --symfs is used to point to the debug binaries, we send in the non-debug filenames to libunwind, which leads to libunwind not finding the debug frame. Fix this by preferring the file in --symfs, if it is available. Signed-off-by: Rabin Vincent <rabin.vincent@axis.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Rabin Vincent <rabinv@axis.com> Link: http://lkml.kernel.org/r/1446104978-26429-1-git-send-email-rabin.vincent@axis.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Compile scriptlets to BPF objects when passing '.c' to --eventWang Nan2015-10-296-9/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch provides infrastructure for passing source files to --event directly using: # perf record --event bpf-file.c command This patch does following works: 1) Allow passing '.c' file to '--event'. parse_events_load_bpf() is expanded to allow caller tell it whether the passed file is source file or object. 2) llvm__compile_bpf() is called to compile the '.c' file, the result is saved into memory. Use bpf_object__open_buffer() to load the in-memory object. Introduces a bpf-script-example.c so we can manually test it: # perf record --clang-opt "-DLINUX_VERSION_CODE=0x40200" --event ./bpf-script-example.c sleep 1 Note that '--clang-opt' must put before '--event'. Futher patches will merge it into a testcase so can be tested automatically. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-10-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Attach eBPF filter to perf eventWang Nan2015-10-293-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the final patch which makes basic BPF filter work. After applying this patch, users are allowed to use BPF filter like: # perf record --event ./hello_world.o ls A bpf_fd field is appended to 'struct evsel', and setup during the callback function add_bpf_event() for each 'probe_trace_event'. PERF_EVENT_IOC_SET_BPF ioctl is used to attach eBPF program to a newly created perf event. The file descriptor of the eBPF program is passed to perf record using previous patches, and stored into evsel->bpf_fd. It is possible that different perf event are created for one kprobe events for different CPUs. In this case, when trying to call the ioctl, EEXIST will be return. This patch doesn't treat it as an error. Committer note: The bpf proggie used so far: __attribute__((section("fork=_do_fork"), used)) int fork(void *ctx) { return 0; } char _license[] __attribute__((section("license"), used)) = "GPL"; int _version __attribute__((section("version"), used)) = 0x40300; failed to produce any samples, even with forks happening and it being running in system wide mode. That is because now the filter is being associated, and the code above always returns zero, meaning that all forks will be probed but filtered away ;-/ Change it to 'return 1;' instead and after that: # trace --no-syscalls --event /tmp/foo.o 0.000 perf_bpf_probe:fork:(ffffffff8109be30)) 2.333 perf_bpf_probe:fork:(ffffffff8109be30)) 3.725 perf_bpf_probe:fork:(ffffffff8109be30)) 4.550 perf_bpf_probe:fork:(ffffffff8109be30)) ^C# And it works with all tools, including 'perf trace'. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: Collect perf_evsel in BPF object filesWang Nan2015-10-283-7/+99
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch creates a 'struct perf_evsel' for every probe in a BPF object file(s) and fills 'struct evlist' with them. The previously introduced dummy event is now removed. After this patch, the following command: # perf record --event filter.o ls Can trace on each of the probes defined in filter.o. The core of this patch is bpf__foreach_tev(), which calls a callback function for each 'struct probe_trace_event' event for a bpf program with each associated file descriptors. The add_bpf_event() callback creates evsels by calling parse_events_add_tracepoint(). Since bpf-loader.c will not be built if libbpf is turned off, an empty bpf__foreach_tev() is defined in bpf-loader.h to avoid build errors. Committer notes: Before: # /tmp/oldperf record --event /tmp/foo.o -a usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.198 MB perf.data ] # perf evlist /tmp/foo.o # perf evlist -v /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 I.e. we create just the PERF_TYPE_SOFTWARE (type: 1), PERF_COUNT_SW_DUMMY(config 0x9) event, now, with this patch: # perf record --event /tmp/foo.o -a usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.210 MB perf.data ] # perf evlist -v perf_bpf_probe:fork: type: 2, size: 112, config: 0x6bd, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 # We now have a PERF_TYPE_SOFTWARE (type: 1), but the config states 0x6bd, which is how, after setting up the event via the kprobes interface, the 'perf_bpf_probe:fork' event is accessible via the perf_event_open syscall. This is all transient, as soon as the 'perf record' session ends, these probes will go away. To see how it looks like, lets try doing a neverending session, one that expects a control+C to end: # perf record --event /tmp/foo.o -a So, with that in place, we can use 'perf probe' to see what is in place: # perf probe -l perf_bpf_probe:fork (on _do_fork@acme/git/linux/kernel/fork.c) We also can use debugfs: [root@felicio ~]# cat /sys/kernel/debug/tracing/kprobe_events p:perf_bpf_probe/fork _text+638512 Ok, now lets stop and see if we got some forks: [root@felicio linux]# perf record --event /tmp/foo.o -a ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.325 MB perf.data (111 samples) ] [root@felicio linux]# perf script sshd 1271 [003] 81797.507678: perf_bpf_probe:fork: (ffffffff8109be30) sshd 18309 [000] 81797.524917: perf_bpf_probe:fork: (ffffffff8109be30) sshd 18309 [001] 81799.381603: perf_bpf_probe:fork: (ffffffff8109be30) sshd 18309 [001] 81799.408635: perf_bpf_probe:fork: (ffffffff8109be30) <SNIP> Sure enough, we have 111 forks :-) Callchains seems to work as well: # perf report --stdio --no-child # To display the perf.data header info, please use --header/--header-only options. # # Total Lost Samples: 0 # # Samples: 562 of event 'perf_bpf_probe:fork' # Event count (approx.): 562 # # Overhead Command Shared Object Symbol # ........ ........ ................ ............ # 44.66% sh [kernel.vmlinux] [k] _do_fork | ---_do_fork entry_SYSCALL_64_fastpath __libc_fork make_child 26.16% make [kernel.vmlinux] [k] _do_fork <SNIP> # Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-7-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Load eBPF object into kernelWang Nan2015-10-283-0/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch utilizes bpf_object__load() provided by libbpf to load all objects into kernel. Committer notes: Testing it: When using an incorrect kernel version number, i.e., having this in your eBPF proggie: int _version __attribute__((section("version"), used)) = 0x40100; For a 4.3.0-rc6+ kernel, say, this happens and needs checking at event parsing time, to provide a better error report to the user: # perf record --event /tmp/foo.o sleep 1 libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: libbpf: -- END LOG -- libbpf: failed to load program 'fork=_do_fork' libbpf: failed to load object '/tmp/foo.o' event syntax error: '/tmp/foo.o' \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel? (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events If we instead make it match, i.e. use 0x40300 on this v4.3.0-rc6+ kernel, the whole process goes thru: # perf record --event /tmp/foo.o -a usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.202 MB perf.data ] # perf evlist -v /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 # Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-6-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Create probe points for BPF programsWang Nan2015-10-283-1/+268
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces bpf__{un,}probe() functions to enable callers to create kprobe points based on section names a BPF program. It parses the section names in the program and creates corresponding 'struct perf_probe_event' structures. The parse_perf_probe_command() function is used to do the main parsing work. The resuling 'struct perf_probe_event' is stored into program private data for further using. By utilizing the new probing API, this patch creates probe points during event parsing. To ensure probe points be removed correctly, register an atexit hook so even perf quit through exit() bpf__clear() is still called, so probing points are cleared. Note that bpf_clear() should be registered before bpf__probe() is called, so failure of bpf__probe() can still trigger bpf__clear() to remove probe points which are already probed. strerror style error reporting scaffold is created by this patch. bpf__strerror_probe() is the first error reporting function in bpf-loader.c. Committer note: Trying it: To build a test eBPF object file: I am testing using a script I built from the 'perf test -v LLVM' output: $ cat ~/bin/hello-ebpf export KERNEL_INC_OPTIONS="-nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.8.3/include -I/home/acme/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/acme/git/linux/include -Iinclude -I/home/acme/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/acme/git/linux/include/uapi -Iinclude/generated/uapi -include /home/acme/git/linux/include/linux/kconfig.h" export WORKING_DIR=/lib/modules/4.2.0/build export CLANG_SOURCE=- export CLANG_OPTIONS=-xc OBJ=/tmp/foo.o rm -f $OBJ echo '__attribute__((section("fork=do_fork"), used)) int fork(void *ctx) {return 0;} char _license[] __attribute__((section("license"), used)) = "GPL";int _version __attribute__((section("version"), used)) = 0x40100;' | \ clang -D__KERNEL__ $CLANG_OPTIONS $KERNEL_INC_OPTIONS -Wno-unused-value -Wno-pointer-sign -working-directory $WORKING_DIR -c "$CLANG_SOURCE" -target bpf -O2 -o /tmp/foo.o && file $OBJ --- First asking to put a probe in a function not present in the kernel (misses the initial _): $ perf record --event /tmp/foo.o sleep 1 Probe point 'do_fork' not found. event syntax error: '/tmp/foo.o' \___ You need to check probing points in BPF file (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events $ --- Now, with "__attribute__((section("fork=_do_fork"), used)): $ grep _do_fork /proc/kallsyms ffffffff81099ab0 T _do_fork $ perf record --event /tmp/foo.o sleep 1 Failed to open kprobe_events: Permission denied event syntax error: '/tmp/foo.o' \___ Permission denied --- Cool, we need to provide some better hints, "kprobe_events" is too low level, one doesn't strictly need to know the precise details of how these things are put in place, so something that shows the command needed to fix the permissions would be more helpful. Lets try as root instead: # perf record --event /tmp/foo.o sleep 1 Lowering default frequency rate to 1000. Please consider tweaking /proc/sys/kernel/perf_event_max_sample_rate. [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data ] # perf evlist /tmp/foo.o [root@felicio ~]# perf evlist -v /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period, sample_freq }: 1000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 --- Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-5-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Enable passing bpf object file to --eventWang Nan2015-10-285-1/+86
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By introducing new rules in tools/perf/util/parse-events.[ly], this patch enables 'perf record --event bpf_file.o' to select events by an eBPF object file. It calls parse_events_load_bpf() to load that file, which uses bpf__prepare_load() and finally calls bpf_object__open() for the object files. After applying this patch, commands like: # perf record --event foo.o sleep become possible. However, at this point it is unable to link any useful things onto the evsel list because the creating of probe points and BPF program attaching have not been implemented. Before real events are possible to be extracted, to avoid perf report error because of empty evsel list, this patch link a dummy evsel. The dummy event related code will be removed when probing and extracting code is ready. Commiter notes: Using it: $ ls -la foo.o ls: cannot access foo.o: No such file or directory $ perf record --event foo.o sleep libbpf: failed to open foo.o: No such file or directory event syntax error: 'foo.o' \___ BPF object file 'foo.o' is invalid (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events $ $ file /tmp/build/perf/perf.o /tmp/build/perf/perf.o: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), not stripped $ perf record --event /tmp/build/perf/perf.o sleep libbpf: /tmp/build/perf/perf.o is not an eBPF object file event syntax error: '/tmp/build/perf/perf.o' \___ BPF object file '/tmp/build/perf/perf.o' is invalid (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events $ $ file /tmp/foo.o /tmp/foo.o: ELF 64-bit LSB relocatable, no machine, version 1 (SYSV), not stripped $ perf record --event /tmp/foo.o sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data ] $ perf evlist /tmp/foo.o $ perf evlist -v /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 $ So, type 1 is PERF_TYPE_SOFTWARE, config 0x9 is PERF_COUNT_SW_DUMMY, ok. $ perf report --stdio Error: The perf.data file has no samples! # To display the perf.data header info, please use --header/--header-only options. # $ Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-4-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf ebpf: Add the libbpf glueWang Nan2015-10-282-0/+86
| | | | | | | | | | | | | | | | | | | | | | The 'bpf-loader.[ch]' files are introduced in this patch. Which will be the interface between perf and libbpf. bpf__prepare_load() resides in bpf-loader.c. Following patches will enrich these two files. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Fix endless loop in dso__split_kallsyms_for_kcoreJiri Olsa2015-10-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | Currently we split symbols based on the map comparison, but symbols are stored within dso objects and maps could point into same dso objects (kernel maps). Hence we could end up changing rbtree we are currently iterating and mess it up. It's easily reproduced on s390x by running: $ perf record -a -- sleep 3 $ perf buildid-list -i perf.data --with-hits The fix is to compare dso objects instead. Reported-by: Michael Petlan <mpetlan@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20151026135130.GA26003@krava.brq.redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>