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author | Masami Hiramatsu <mhiramat@redhat.com> | 2010-03-16 23:06:26 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2010-03-17 12:11:15 +0100 |
commit | 7df2f32956cf0f1a45df38cd0e0fe0c3467580e8 (patch) | |
tree | 1cccbf0d4239ebdd9c0f67762b5a2f0facbe53dc /tools/perf/util/probe-event.c | |
parent | perf probe: List probes with line number and file name (diff) | |
download | linux-7df2f32956cf0f1a45df38cd0e0fe0c3467580e8.tar.xz linux-7df2f32956cf0f1a45df38cd0e0fe0c3467580e8.zip |
perf probe: Add data structure member access support
Support accessing members in the data structures. With this,
perf-probe accepts data-structure members(IOW, it now accepts
dot '.' and arrow '->' operators) as probe arguemnts.
e.g.
./perf probe --add 'schedule:44 rq->curr'
./perf probe --add 'vfs_read file->f_op->read file->f_path.dentry'
Note that '>' can be interpreted as redirection in command-line.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100316220626.32050.57552.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'tools/perf/util/probe-event.c')
-rw-r--r-- | tools/perf/util/probe-event.c | 90 |
1 files changed, 86 insertions, 4 deletions
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 4e3c1aea7892..64dea6c3d58a 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -262,6 +262,49 @@ static void parse_perf_probe_point(char *arg, struct perf_probe_event *pev) pp->lazy_line); } +/* Parse perf-probe event argument */ +static void parse_perf_probe_arg(const char *str, struct perf_probe_arg *arg) +{ + const char *tmp; + struct perf_probe_arg_field **fieldp; + + pr_debug("parsing arg: %s into ", str); + + tmp = strpbrk(str, "-."); + if (!is_c_varname(str) || !tmp) { + /* A variable, register, symbol or special value */ + arg->name = xstrdup(str); + pr_debug("%s\n", arg->name); + return; + } + + /* Structure fields */ + arg->name = xstrndup(str, tmp - str); + pr_debug("%s, ", arg->name); + fieldp = &arg->field; + + do { + *fieldp = xzalloc(sizeof(struct perf_probe_arg_field)); + if (*tmp == '.') { + str = tmp + 1; + (*fieldp)->ref = false; + } else if (tmp[1] == '>') { + str = tmp + 2; + (*fieldp)->ref = true; + } else + semantic_error("Argument parse error: %s", str); + + tmp = strpbrk(str, "-."); + if (tmp) { + (*fieldp)->name = xstrndup(str, tmp - str); + pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref); + fieldp = &(*fieldp)->next; + } + } while (tmp); + (*fieldp)->name = xstrdup(str); + pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref); +} + /* Parse perf-probe event command */ void parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev) { @@ -281,7 +324,7 @@ void parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev) pev->nargs = argc - 1; pev->args = xzalloc(sizeof(struct perf_probe_arg) * pev->nargs); for (i = 0; i < pev->nargs; i++) { - pev->args[i].name = xstrdup(argv[i + 1]); + parse_perf_probe_arg(argv[i + 1], &pev->args[i]); if (is_c_varname(pev->args[i].name) && pev->point.retprobe) semantic_error("You can't specify local variable for" " kretprobe"); @@ -353,6 +396,33 @@ void parse_kprobe_trace_command(const char *cmd, struct kprobe_trace_event *tev) argv_free(argv); } +/* Compose only probe arg */ +int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len) +{ + struct perf_probe_arg_field *field = pa->field; + int ret; + char *tmp = buf; + + ret = e_snprintf(tmp, len, "%s", pa->name); + if (ret <= 0) + goto error; + tmp += ret; + len -= ret; + + while (field) { + ret = e_snprintf(tmp, len, "%s%s", field->ref ? "->" : ".", + field->name); + if (ret <= 0) + goto error; + tmp += ret; + len -= ret; + field = field->next; + } + return tmp - buf; +error: + die("Failed to synthesize perf probe argument: %s", strerror(-ret)); +} + /* Compose only probe point (not argument) */ static char *synthesize_perf_probe_point(struct perf_probe_point *pp) { @@ -563,6 +633,7 @@ void convert_to_perf_probe_event(struct kprobe_trace_event *tev, void clear_perf_probe_event(struct perf_probe_event *pev) { struct perf_probe_point *pp = &pev->point; + struct perf_probe_arg_field *field, *next; int i; if (pev->event) @@ -575,9 +646,18 @@ void clear_perf_probe_event(struct perf_probe_event *pev) free(pp->function); if (pp->lazy_line) free(pp->lazy_line); - for (i = 0; i < pev->nargs; i++) + for (i = 0; i < pev->nargs; i++) { if (pev->args[i].name) free(pev->args[i].name); + field = pev->args[i].field; + while (field) { + next = field->next; + if (field->name) + free(field->name); + free(field); + field = next; + } + } if (pev->args) free(pev->args); memset(pev, 0, sizeof(*pev)); @@ -682,8 +762,10 @@ static void show_perf_probe_event(struct perf_probe_event *pev) if (pev->nargs > 0) { printf(" with"); - for (i = 0; i < pev->nargs; i++) - printf(" %s", pev->args[i].name); + for (i = 0; i < pev->nargs; i++) { + synthesize_perf_probe_arg(&pev->args[i], buf, 128); + printf(" %s", buf); + } } printf(")\n"); free(place); |