From 27cfef009ae8a1019d174153987ce22a0e6677fc Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Tue, 8 Dec 2015 02:25:43 +0000 Subject: [PATCH] perf script: Add support for PERF_TYPE_BREAKPOINT Useful for getting stack traces for hardware breakpoint events. Test result: Before this patch: # ~/perf record -g -e mem:0x600980 ./sample [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.011 MB perf.data (12 samples) ] # ~/perf script # ~/perf script -F comm,tid,pid,time,event,ip,sym,dso sample 22520/22520 97457.836294: mem:0x600980: 5a4ad8 __clear_user (/lib/modules/4.3.0-rc4+/build/vmlinux) ... 3f41ba sys_execve (/lib/modules/4.3.0-rc4+/build/vmlinux) 979395 return_from_execve (/lib/modules/4.3.0-rc4+/build/vmlinux) 7f1b59719cf7 [unknown] ([unknown]) sample 22520/22520 97457.836648: mem:0x600980: 532 main (/home/w00229757/DataBreakpoints/sample) 21bd5 __libc_start_main (/tmp/oxygen_root-root/lib64/libc-2.18.so) ... After this patch: # ~/perf script sample 22520 97457.836294: mem:0x600980: 5a4ad8 __clear_user (/lib/modules/4.3.0-rc4+/build/vmlinux) ... 3f41ba sys_execve (/lib/modules/4.3.0-rc4+/build/vmlinux) 979395 return_from_execve (/lib/modules/4.3.0-rc4+/build/vmlinux) 7f1b59719cf7 [unknown] ([unknown]) sample 22520 97457.836648: mem:0x600980: 532 main (/home/w00229757/DataBreakpoints/sample) 21bd5 __libc_start_main (/tmp/oxygen_root-root/lib64/libc-2.18.so) Committer note: So, further testing, lets do it for a kernel global variable, tcp_hashinfo: # grep -w tcp_hashinfo /proc/kallsyms ffffffff8202fc00 B tcp_hashinfo # Note: allow specifying mem:tcp_hashinfo: # perf record -g -e mem:0xffffffff81c65ac0 -a ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.790 MB perf.data ] # # perf evlist mem:0xffffffff8202fc00 # perf evlist -v mem:0xffffffff8202fc00: type: 5, size: 112, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CALLCHAIN|CPU, disabled: 1, inherit: 1, mmap: 1, comm: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, bp_type: 3, { bp_addr, config1 }: 0xffffffff8202fc00, { bp_len, config2 }: 0x4 # Then, after this patch: # perf script swapper 0 [000] 171036.986988: mem:0xffffffff8202fc00: 8a0fb5 __inet_lookup_established (/lib/modules/4.3.0+/build/vmlinux) 8bc09d tcp_v4_early_demux (/lib/modules/4.3.0+/build/vmlinux) 896def ip_rcv_finish (/lib/modules/4.3.0+/build/vmlinux) 8976c2 ip_rcv (/lib/modules/4.3.0+/build/vmlinux) 855eba __netif_receive_skb_core (/lib/modules/4.3.0+/build/vmlinux) 8565d8 __netif_receive_skb (/lib/modules/4.3.0+/build/vmlinux) 8572a8 process_backlog (/lib/modules/4.3.0+/build/vmlinux) 856b11 net_rx_action (/lib/modules/4.3.0+/build/vmlinux) 2a284b __do_softirq (/lib/modules/4.3.0+/build/vmlinux) 2a2ba3 irq_exit (/lib/modules/4.3.0+/build/vmlinux) 96b7a4 do_IRQ (/lib/modules/4.3.0+/build/vmlinux) 969807 ret_from_intr (/lib/modules/4.3.0+/build/vmlinux) 804c27 cpuidle_enter (/lib/modules/4.3.0+/build/vmlinux) 2ded22 call_cpuidle (/lib/modules/4.3.0+/build/vmlinux) 2defb6 cpu_startup_entry (/lib/modules/4.3.0+/build/vmlinux) 95d5bc rest_init (/lib/modules/4.3.0+/build/vmlinux) 1163ffa start_kernel ([kernel.vmlinux].init.text) 11634d7 x86_64_start_reservations ([kernel.vmlinux].init.text) 1163623 x86_64_start_kernel ([kernel.vmlinux].init.text) Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: David S. Miller Cc: Jiri Olsa Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1449541544-67621-16-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-script.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index 3c3f8d0e3064..d259e9aa3a71 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -130,6 +130,18 @@ static struct { .invalid_fields = PERF_OUTPUT_TRACE, }, + + [PERF_TYPE_BREAKPOINT] = { + .user_set = false, + + .fields = PERF_OUTPUT_COMM | PERF_OUTPUT_TID | + PERF_OUTPUT_CPU | PERF_OUTPUT_TIME | + PERF_OUTPUT_EVNAME | PERF_OUTPUT_IP | + PERF_OUTPUT_SYM | PERF_OUTPUT_DSO | + PERF_OUTPUT_PERIOD, + + .invalid_fields = PERF_OUTPUT_TRACE, + }, }; static bool output_set_by_user(void) @@ -1129,6 +1141,8 @@ static int parse_output_fields(const struct option *opt __maybe_unused, type = PERF_TYPE_TRACEPOINT; else if (!strcmp(str, "raw")) type = PERF_TYPE_RAW; + else if (!strcmp(str, "break")) + type = PERF_TYPE_BREAKPOINT; else { fprintf(stderr, "Invalid event type in field string.\n"); rc = -EINVAL;