From 909b0360ae358f212f526e171ea4ef433b1b4103 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Thu, 28 Apr 2016 03:37:14 +0900 Subject: [PATCH] perf probe: Use strbuf for making strings Replace many fixed-length char array with strbuf to stringify perf_probe_event and probe_trace_event etc. Signed-off-by: Masami Hiramatsu Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Hemant Kumar Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20160427183713.23446.97377.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-event.c | 246 ++++++++++++--------------------- tools/perf/util/probe-event.h | 2 +- tools/perf/util/probe-finder.c | 14 +- 3 files changed, 93 insertions(+), 169 deletions(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index a9774628c6f6..85d82f4dc5e9 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -1673,69 +1673,51 @@ out: } /* 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; @@ -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 @@ -1791,45 +1760,30 @@ 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) @@ -1837,60 +1791,41 @@ static int synthesize_probe_trace_arg(struct probe_trace_arg *arg, /* 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. @@ -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, @@ -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 */ @@ -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; @@ -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 */ diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h index e54e7b011577..e2209623f981 100644 --- a/tools/perf/util/probe-event.h +++ b/tools/perf/util/probe-event.h @@ -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); diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index b3bd0fba0237..9f688758b000 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -553,7 +553,7 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf) static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf) { Dwarf_Die vr_die; - char buf[32], *ptr; + char *buf, *ptr; int ret = 0; /* Copy raw parameters */ @@ -563,13 +563,13 @@ static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf) if (pf->pvar->name) pf->tvar->name = strdup(pf->pvar->name); else { - ret = synthesize_perf_probe_arg(pf->pvar, buf, 32); - if (ret < 0) - return ret; + buf = synthesize_perf_probe_arg(pf->pvar); + if (!buf) + return -ENOMEM; ptr = strchr(buf, ':'); /* Change type separator to _ */ if (ptr) *ptr = '_'; - pf->tvar->name = strdup(buf); + pf->tvar->name = buf; } if (pf->tvar->name == NULL) return -ENOMEM; @@ -1334,8 +1334,8 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data) if (ret2 == 0) { strlist__add(vl->vars, strbuf_detach(&buf, NULL)); - } - strbuf_release(&buf); + } else + strbuf_release(&buf); } } -- 2.20.1