Skip to content

Commit

Permalink
perf probe: Use strbuf for making strings
Browse files Browse the repository at this point in the history 
Replace many fixed-length char array with strbuf to stringify
perf_probe_event and probe_trace_event etc.

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Masami Hiramatsu <[email protected]>
Cc: Ananth N Mavinakayanahalli <[email protected]>
Cc: Hemant Kumar <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/20160427183713.23446.97377.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
  • Loading branch information
@mhiramathitachi @acmel
mhiramathitachi authored and acmel committed Apr 28, 2016
1 parent 81d64f4 commit 909b036
Show file tree
Hide file tree
Showing 3 changed files with 93 additions and 169 deletions.
246 changes: 85 additions & 161 deletions tools/perf/util/probe-event.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1673,69 +1673,51 @@ int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev)
}

/* Compose only probe arg */
int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len)
char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
{
struct perf_probe_arg_field *field = pa->field;
int ret;
char *tmp = buf;
struct strbuf buf;
char *ret;

strbuf_init(&buf, 64);
if (pa->name && pa->var)
ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var);
strbuf_addf(&buf, "%s=%s", pa->name, pa->var);
else
ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var);
if (ret <= 0)
goto error;
tmp += ret;
len -= ret;
strbuf_addstr(&buf, pa->name ?: pa->var);

while (field) {
if (field->name[0] == '[')
ret = e_snprintf(tmp, len, "%s", field->name);
strbuf_addstr(&buf, field->name);
else
ret = e_snprintf(tmp, len, "%s%s",
field->ref ? "->" : ".", field->name);
if (ret <= 0)
goto error;
tmp += ret;
len -= ret;
strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".",
field->name);
field = field->next;
}

if (pa->type) {
ret = e_snprintf(tmp, len, ":%s", pa->type);
if (ret <= 0)
goto error;
tmp += ret;
len -= ret;
}
if (pa->type)
strbuf_addf(&buf, ":%s", pa->type);

ret = strbuf_detach(&buf, NULL);

return tmp - buf;
error:
pr_debug("Failed to synthesize perf probe argument: %d\n", ret);
return ret;
}

/* Compose only probe point (not argument) */
static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
{
char *buf, *tmp;
char offs[32] = "", line[32] = "", file[32] = "";
int ret, len;

buf = zalloc(MAX_CMDLEN);
if (buf == NULL) {
ret = -ENOMEM;
goto error;
}
if (pp->offset) {
ret = e_snprintf(offs, 32, "+%lu", pp->offset);
if (ret <= 0)
goto error;
}
if (pp->line) {
ret = e_snprintf(line, 32, ":%d", pp->line);
if (ret <= 0)
goto error;
struct strbuf buf;
char *tmp;
int len;

strbuf_init(&buf, 64);
if (pp->function) {
strbuf_addstr(&buf, pp->function);
if (pp->offset)
strbuf_addf(&buf, "+%lu", pp->offset);
else if (pp->line)
strbuf_addf(&buf, ":%d", pp->line);
else if (pp->retprobe)
strbuf_addstr(&buf, "%return");
}
if (pp->file) {
tmp = pp->file;
Expand All @@ -1744,25 +1726,12 @@ static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
tmp = strchr(pp->file + len - 30, '/');
tmp = tmp ? tmp + 1 : pp->file + len - 30;
}
ret = e_snprintf(file, 32, "@%s", tmp);
if (ret <= 0)
goto error;
strbuf_addf(&buf, "@%s", tmp);
if (!pp->function && pp->line)
strbuf_addf(&buf, ":%d", pp->line);
}

if (pp->function)
ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
offs, pp->retprobe ? "%return" : "", line,
file);
else
ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
if (ret <= 0)
goto error;

return buf;
error:
pr_debug("Failed to synthesize perf probe point: %d\n", ret);
free(buf);
return NULL;
return strbuf_detach(&buf, NULL);
}

#if 0
Expand Down Expand Up @@ -1791,106 +1760,72 @@ char *synthesize_perf_probe_command(struct perf_probe_event *pev)
#endif

static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
char **buf, size_t *buflen,
int depth)
struct strbuf *buf, int depth)
{
int ret;
if (ref->next) {
depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
buflen, depth + 1);
depth + 1);
if (depth < 0)
goto out;
}

ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset);
if (ret < 0)
depth = ret;
else {
*buf += ret;
*buflen -= ret;
}
strbuf_addf(buf, "%+ld(", ref->offset);
out:
return depth;

}

static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
char *buf, size_t buflen)
struct strbuf *buf)
{
struct probe_trace_arg_ref *ref = arg->ref;
int ret, depth = 0;
char *tmp = buf;
int depth = 0;

/* Argument name or separator */
if (arg->name)
ret = e_snprintf(buf, buflen, " %s=", arg->name);
strbuf_addf(buf, " %s=", arg->name);
else
ret = e_snprintf(buf, buflen, " ");
if (ret < 0)
return ret;
buf += ret;
buflen -= ret;
strbuf_addch(buf, ' ');

/* Special case: @XXX */
if (arg->value[0] == '@' && arg->ref)
ref = ref->next;

/* Dereferencing arguments */
if (ref) {
depth = __synthesize_probe_trace_arg_ref(ref, &buf,
&buflen, 1);
depth = __synthesize_probe_trace_arg_ref(ref, buf, 1);
if (depth < 0)
return depth;
}

/* Print argument value */
if (arg->value[0] == '@' && arg->ref)
ret = e_snprintf(buf, buflen, "%s%+ld", arg->value,
arg->ref->offset);
strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset);
else
ret = e_snprintf(buf, buflen, "%s", arg->value);
if (ret < 0)
return ret;
buf += ret;
buflen -= ret;
strbuf_addstr(buf, arg->value);

/* Closing */
while (depth--) {
ret = e_snprintf(buf, buflen, ")");
if (ret < 0)
return ret;
buf += ret;
buflen -= ret;
}
while (depth--)
strbuf_addch(buf, ')');
/* Print argument type */
if (arg->type) {
ret = e_snprintf(buf, buflen, ":%s", arg->type);
if (ret <= 0)
return ret;
buf += ret;
}
if (arg->type)
strbuf_addf(buf, ":%s", arg->type);

return buf - tmp;
return 0;
}

char *synthesize_probe_trace_command(struct probe_trace_event *tev)
{
struct probe_trace_point *tp = &tev->point;
char *buf;
int i, len, ret;

buf = zalloc(MAX_CMDLEN);
if (buf == NULL)
return NULL;

len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
tev->group, tev->event);
if (len <= 0)
goto error;
struct strbuf buf;
char *ret = NULL;
int i;

/* Uprobes must have tp->module */
if (tev->uprobes && !tp->module)
goto error;
return NULL;

strbuf_init(&buf, 32);
strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
tev->group, tev->event);
/*
* If tp->address == 0, then this point must be a
* absolute address uprobe.
Expand All @@ -1904,34 +1839,23 @@ char *synthesize_probe_trace_command(struct probe_trace_event *tev)

/* Use the tp->address for uprobes */
if (tev->uprobes)
ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s:0x%lx",
tp->module, tp->address);
strbuf_addf(&buf, "%s:0x%lx", tp->module, tp->address);
else if (!strncmp(tp->symbol, "0x", 2))
/* Absolute address. See try_to_find_absolute_address() */
ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s%s0x%lx",
tp->module ?: "", tp->module ? ":" : "",
tp->address);
strbuf_addf(&buf, "%s%s0x%lx", tp->module ?: "",
tp->module ? ":" : "", tp->address);
else
ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s%s%s+%lu",
tp->module ?: "", tp->module ? ":" : "",
tp->symbol, tp->offset);

if (ret <= 0)
goto error;
len += ret;
strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "",
tp->module ? ":" : "", tp->symbol, tp->offset);

for (i = 0; i < tev->nargs; i++) {
ret = synthesize_probe_trace_arg(&tev->args[i], buf + len,
MAX_CMDLEN - len);
if (ret <= 0)
for (i = 0; i < tev->nargs; i++)
if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0)
goto error;
len += ret;
}

return buf;
ret = strbuf_detach(&buf, NULL);
error:
free(buf);
return NULL;
strbuf_release(&buf);
return ret;
}

static int find_perf_probe_point_from_map(struct probe_trace_point *tp,
Expand Down Expand Up @@ -2013,7 +1937,7 @@ static int convert_to_perf_probe_point(struct probe_trace_point *tp,
static int convert_to_perf_probe_event(struct probe_trace_event *tev,
struct perf_probe_event *pev, bool is_kprobe)
{
char buf[64] = "";
struct strbuf buf = STRBUF_INIT;
int i, ret;

/* Convert event/group name */
Expand All @@ -2036,9 +1960,9 @@ static int convert_to_perf_probe_event(struct probe_trace_event *tev,
if (tev->args[i].name)
pev->args[i].name = strdup(tev->args[i].name);
else {
ret = synthesize_probe_trace_arg(&tev->args[i],
buf, 64);
pev->args[i].name = strdup(buf);
strbuf_init(&buf, 32);
ret = synthesize_probe_trace_arg(&tev->args[i], &buf);
pev->args[i].name = strbuf_detach(&buf, NULL);
}
if (pev->args[i].name == NULL && ret >= 0)
ret = -ENOMEM;
Expand Down Expand Up @@ -2216,37 +2140,37 @@ static int perf_probe_event__sprintf(const char *group, const char *event,
const char *module,
struct strbuf *result)
{
int i, ret;
char buf[128];
char *place;
int i;
char *buf;

/* Synthesize only event probe point */
place = synthesize_perf_probe_point(&pev->point);
if (!place)
return -EINVAL;
if (asprintf(&buf, "%s:%s", group, event) < 0)
return -errno;
strbuf_addf(result, " %-20s (on ", buf);
free(buf);

ret = e_snprintf(buf, 128, "%s:%s", group, event);
if (ret < 0)
goto out;
/* Synthesize only event probe point */
buf = synthesize_perf_probe_point(&pev->point);
if (!buf)
return -ENOMEM;
strbuf_addstr(result, buf);
free(buf);

strbuf_addf(result, " %-20s (on %s", buf, place);
if (module)
strbuf_addf(result, " in %s", module);

if (pev->nargs > 0) {
strbuf_add(result, " with", 5);
for (i = 0; i < pev->nargs; i++) {
ret = synthesize_perf_probe_arg(&pev->args[i],
buf, 128);
if (ret < 0)
goto out;
buf = synthesize_perf_probe_arg(&pev->args[i]);
if (!buf)
return -ENOMEM;
strbuf_addf(result, " %s", buf);
free(buf);
}
}
strbuf_addch(result, ')');
out:
free(place);
return ret;

return 0;
}

/* Show an event */
Expand Down
2 changes: 1 addition & 1 deletion tools/perf/util/probe-event.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -120,7 +120,7 @@ int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev);
/* Events to command string */
char *synthesize_perf_probe_command(struct perf_probe_event *pev);
char *synthesize_probe_trace_command(struct probe_trace_event *tev);
int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len);
char *synthesize_perf_probe_arg(struct perf_probe_arg *pa);

/* Check the perf_probe_event needs debuginfo */
bool perf_probe_event_need_dwarf(struct perf_probe_event *pev);
Expand Down
Loading

0 comments on commit 909b036

Please sign in to comment.