From 11c8e39f5133aed9e0f8ffc624c7d5f64c97bc79 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 6 Apr 2016 14:33:07 -0300 Subject: [PATCH] perf trace: Infrastructure to show COMM strings for syscalls returning PIDs Starting with clone, waitid and wait4: # trace -e waitid,wait4 1.385 ( 1.385 ms): bash/12122 wait4(upid: -1, stat_addr: 0x7ffe0cee1720, options: UNTRACED|CONTINUED) = 1210 (ls) 1.426 ( 0.002 ms): bash/12122 wait4(upid: -1, stat_addr: 0x7ffe0cee1150, options: NOHANG|UNTRACED|CONTINUED) = 0 3.293 ( 0.604 ms): bash/1211 wait4(upid: -1, stat_addr: 0x7ffe0cee0560 ) = 1214 (sed) 3.342 ( 0.002 ms): bash/1211 wait4(upid: -1, stat_addr: 0x7ffe0cee01d0, options: NOHANG ) = -1 ECHILD No child processes 3.576 ( 0.016 ms): bash/12122 wait4(upid: -1, stat_addr: 0x7ffe0cee0550, options: NOHANG|UNTRACED|CONTINUED) = 1211 (bash) ^C# trace -e clone 0.027 ( 0.000 ms): systemd/1 ... [continued]: clone()) = 1227 (systemd) 0.050 ( 0.000 ms): systemd/1227 ... [continued]: clone()) = 0 ^C[root@jouet ~]# Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-lyf5d3y5j15wikjb6pe6ukoi@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 9a6c7b1fd5a1..22a4901d057b 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -1082,6 +1082,7 @@ static struct syscall_fmt { size_t (*arg_scnprintf[6])(char *bf, size_t size, struct syscall_arg *arg); void *arg_parm[6]; bool errmsg; + bool errpid; bool timeout; bool hexret; } syscall_fmts[] = { @@ -1099,6 +1100,7 @@ static struct syscall_fmt { { .name = "chroot", .errmsg = true, .arg_scnprintf = { [0] = SCA_FILENAME, /* filename */ }, }, { .name = "clock_gettime", .errmsg = true, STRARRAY(0, clk_id, clockid), }, + { .name = "clone", .errpid = true, }, { .name = "close", .errmsg = true, .arg_scnprintf = { [0] = SCA_CLOSE_FD, /* fd */ }, }, { .name = "connect", .errmsg = true, }, @@ -1365,9 +1367,9 @@ static struct syscall_fmt { .arg_scnprintf = { [0] = SCA_FILENAME, /* filename */ }, }, { .name = "vmsplice", .errmsg = true, .arg_scnprintf = { [0] = SCA_FD, /* fd */ }, }, - { .name = "wait4", .errmsg = true, + { .name = "wait4", .errpid = true, .arg_scnprintf = { [2] = SCA_WAITID_OPTIONS, /* options */ }, }, - { .name = "waitid", .errmsg = true, + { .name = "waitid", .errpid = true, .arg_scnprintf = { [3] = SCA_WAITID_OPTIONS, /* options */ }, }, { .name = "write", .errmsg = true, .arg_scnprintf = { [0] = SCA_FD, /* fd */ }, }, @@ -2156,7 +2158,7 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel, if (sc->fmt == NULL) { signed_print: fprintf(trace->output, ") = %ld", ret); - } else if (ret < 0 && sc->fmt->errmsg) { + } else if (ret < 0 && (sc->fmt->errmsg || sc->fmt->errpid)) { char bf[STRERR_BUFSIZE]; const char *emsg = strerror_r(-ret, bf, sizeof(bf)), *e = audit_errno_to_name(-ret); @@ -2166,7 +2168,16 @@ signed_print: fprintf(trace->output, ") = 0 Timeout"); else if (sc->fmt->hexret) fprintf(trace->output, ") = %#lx", ret); - else + else if (sc->fmt->errpid) { + struct thread *child = machine__find_thread(trace->host, ret, ret); + + if (child != NULL) { + fprintf(trace->output, ") = %ld", ret); + if (child->comm_set) + fprintf(trace->output, " (%s)", thread__comm_str(child)); + thread__put(child); + } + } else goto signed_print; fputc('\n', trace->output);