From f932184e282f574cfd34afee917a10b782fd3e76 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 25 Oct 2018 17:24:45 -0300 Subject: [PATCH] perf trace: Consider syscall aliases too When trying to trace the 'umount' syscall on x86_64 I noticed that it was failing: # trace -e umount umount /mnt event syntax error: 'umount' \___ parser error Run 'perf list' for a list of valid events Usage: perf trace [] [] or: perf trace [] -- [] or: perf trace record [] [] or: perf trace record [] -- [] -e, --event event/syscall selector. use 'perf list' to list available events # This is because in the x86-64 we have it just as 'umount2': $ grep umount arch/x86/entry/syscalls/syscall_64.tbl 166 common umount2 __x64_sys_umount $ So if the syscall name fails, try fallbacking to looking at the aliases we have in the syscall_fmts table to then re-lookup, now: # trace -e umount umount -f /mnt umount: /mnt: not mounted. 1.759 ( 0.004 ms): umount/18365 umount2(name: 0x55fbfcbc4480, flags: 1) = -1 EINVAL Invalid argument # Time to beautify the flags arg :-) Cc: Adrian Hunter Cc: Benjamin Peterson Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-ukweodgzbmjd25lfkgryeft1@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 76c14c0129fc..db8711061ca3 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -862,6 +862,18 @@ static struct syscall_fmt *syscall_fmt__find(const char *name) return bsearch(name, syscall_fmts, nmemb, sizeof(struct syscall_fmt), syscall_fmt__cmp); } +static struct syscall_fmt *syscall_fmt__find_by_alias(const char *alias) +{ + int i, nmemb = ARRAY_SIZE(syscall_fmts); + + for (i = 0; i < nmemb; ++i) { + if (syscall_fmts[i].alias && strcmp(syscall_fmts[i].alias, alias) == 0) + return &syscall_fmts[i]; + } + + return NULL; +} + /* * is_exit: is this "exit" or "exit_group"? * is_open: is this "open" or "openat"? To associate the fd returned in sys_exit with the pathname in sys_enter. @@ -3195,6 +3207,7 @@ static int trace__parse_events_option(const struct option *opt, const char *str, int len = strlen(str) + 1, err = -1, list, idx; char *strace_groups_dir = system_path(STRACE_GROUPS_DIR); char group_name[PATH_MAX]; + struct syscall_fmt *fmt; if (strace_groups_dir == NULL) return -1; @@ -3212,12 +3225,19 @@ static int trace__parse_events_option(const struct option *opt, const char *str, if (syscalltbl__id(trace->sctbl, s) >= 0 || syscalltbl__strglobmatch_first(trace->sctbl, s, &idx) >= 0) { list = 1; + goto do_concat; + } + + fmt = syscall_fmt__find_by_alias(s); + if (fmt != NULL) { + list = 1; + s = fmt->name; } else { path__join(group_name, sizeof(group_name), strace_groups_dir, s); if (access(group_name, R_OK) == 0) list = 1; } - +do_concat: if (lists[list]) { sprintf(lists[list] + strlen(lists[list]), ",%s", s); } else {