From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754557AbdLHQ3K (ORCPT ); Fri, 8 Dec 2017 11:29:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:46282 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753026AbdLHQ3F (ORCPT ); Fri, 8 Dec 2017 11:29:05 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9264321920 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=mhiramat@kernel.org From: Masami Hiramatsu To: Arnaldo Carvalho de Melo Cc: Masami Hiramatsu , bhargavb , linux-kernel@vger.kernel.org, Paul Clarke , Ravi Bangoria , Thomas Richter , linux-rt-users@vger.kernel.org, linux-perf-users@vger.kernel.org Subject: [PATCH v3 5/5] perf-probe: Support escaped character in parser Date: Sat, 9 Dec 2017 01:28:41 +0900 Message-Id: <151275052163.24652.18205979384585484358.stgit@devbox> X-Mailer: git-send-email 2.13.6 In-Reply-To: <151275037752.24652.5169845651138876257.stgit@devbox> References: <151275037752.24652.5169845651138876257.stgit@devbox> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Support the special characters escaped by '\' in parser. This allows user to specify versions directly like below. ===== # ./perf probe -x /lib64/libc-2.25.so malloc_get_state\\@GLIBC_2.2.5 Added new event: probe_libc:malloc_get_state (on malloc_get_state@GLIBC_2.2.5 in /usr/lib64/libc-2.25.so) You can now use it in all perf tools, such as: perf record -e probe_libc:malloc_get_state -aR sleep 1 ===== Or, you can use separators in source filename, e.g. ===== # ./perf probe -x /opt/test/a.out foo+bar.c:3 Semantic error :There is non-digit character in offset. Error: Command Parse Error. ===== Usually "+" in source file cause parser error, but ===== # ./perf probe -x /opt/test/a.out foo\\+bar.c:4 Added new event: probe_a:main (on @foo+bar.c:4 in /opt/test/a.out) You can now use it in all perf tools, such as: perf record -e probe_a:main -aR sleep 1 ===== escaped "\+" allows you to specify that. Signed-off-by: Masami Hiramatsu Reviewed-by: Thomas Richter Acked-by: Ravi Bangoria --- Changes in v2: - Add a description and samples in Documentation/perf-probe.txt Changes in v3: - Update for new series. --- tools/perf/Documentation/perf-probe.txt | 16 +++++++++ tools/perf/util/probe-event.c | 57 ++++++++++++++++++------------- tools/perf/util/string.c | 46 +++++++++++++++++++++++++ tools/perf/util/string2.h | 2 + 4 files changed, 98 insertions(+), 23 deletions(-) diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt index f96382692f42..b6866a05edd2 100644 --- a/tools/perf/Documentation/perf-probe.txt +++ b/tools/perf/Documentation/perf-probe.txt @@ -182,6 +182,14 @@ Note that before using the SDT event, the target binary (on which SDT events are For details of the SDT, see below. https://sourceware.org/gdb/onlinedocs/gdb/Static-Probe-Points.html +ESCAPED CHARACTER +----------------- + +In the probe syntax, '=', '@', '+', ':' and ';' are treated as a special character. You can use a backslash ('\') to escape the special characters. +This is useful if you need to probe on a specific versioned symbols, like @GLIBC_... suffixes, or also you need to specify a source file which includes the special characters. +Note that usually single backslash is consumed by shell, so you might need to pass double backslash (\\) or wrapping with single quotes (\'AAA\@BBB'). +See EXAMPLES how it is used. + PROBE ARGUMENT -------------- Each probe argument follows below syntax. @@ -277,6 +285,14 @@ Add a USDT probe to a target process running in a different mount namespace ./perf probe --target-ns -x /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.121-0.b13.el7_3.x86_64/jre/lib/amd64/server/libjvm.so %sdt_hotspot:thread__sleep__end +Add a probe on specific versioned symbol by backslash escape + + ./perf probe -x /lib64/libc-2.25.so 'malloc_get_state\@GLIBC_2.2.5' + +Add a probe in a source file using special characters by backslash escape + + ./perf probe -x /opt/test/a.out 'foo\+bar.c:4' + SEE ALSO -------- diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 0d6c66d51939..735972e7bc6b 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -1325,27 +1325,30 @@ static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev) { char *ptr; - ptr = strchr(*arg, ':'); + ptr = strpbrk_esc(*arg, ":"); if (ptr) { *ptr = '\0'; if (!pev->sdt && !is_c_func_name(*arg)) goto ng_name; - pev->group = strdup(*arg); + pev->group = strdup_esc(*arg); if (!pev->group) return -ENOMEM; *arg = ptr + 1; } else pev->group = NULL; - if (!pev->sdt && !is_c_func_name(*arg)) { + + pev->event = strdup_esc(*arg); + if (pev->event == NULL) + return -ENOMEM; + + if (!pev->sdt && !is_c_func_name(pev->event)) { + zfree(&pev->event); ng_name: + zfree(&pev->group); semantic_error("%s is bad for event name -it must " "follow C symbol-naming rule.\n", *arg); return -EINVAL; } - pev->event = strdup(*arg); - if (pev->event == NULL) - return -ENOMEM; - return 0; } @@ -1373,7 +1376,7 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) arg++; } - ptr = strpbrk(arg, ";=@+%"); + ptr = strpbrk_esc(arg, ";=@+%"); if (pev->sdt) { if (ptr) { if (*ptr != '@') { @@ -1387,7 +1390,7 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) pev->target = build_id_cache__origname(tmp); free(tmp); } else - pev->target = strdup(ptr + 1); + pev->target = strdup_esc(ptr + 1); if (!pev->target) return -ENOMEM; *ptr = '\0'; @@ -1421,13 +1424,14 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) * * Otherwise, we consider arg to be a function specification. */ - if (!strpbrk(arg, "+@%") && (ptr = strpbrk(arg, ";:")) != NULL) { + if (!strpbrk_esc(arg, "+@%")) { + ptr = strpbrk_esc(arg, ";:"); /* This is a file spec if it includes a '.' before ; or : */ - if (memchr(arg, '.', ptr - arg)) + if (ptr && memchr(arg, '.', ptr - arg)) file_spec = true; } - ptr = strpbrk(arg, ";:+@%"); + ptr = strpbrk_esc(arg, ";:+@%"); if (ptr) { nc = *ptr; *ptr++ = '\0'; @@ -1436,7 +1440,7 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) if (arg[0] == '\0') tmp = NULL; else { - tmp = strdup(arg); + tmp = strdup_esc(arg); if (tmp == NULL) return -ENOMEM; } @@ -1469,12 +1473,12 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) arg = ptr; c = nc; if (c == ';') { /* Lazy pattern must be the last part */ - pp->lazy_line = strdup(arg); + pp->lazy_line = strdup(arg); /* let leave escapes */ if (pp->lazy_line == NULL) return -ENOMEM; break; } - ptr = strpbrk(arg, ";:+@%"); + ptr = strpbrk_esc(arg, ";:+@%"); if (ptr) { nc = *ptr; *ptr++ = '\0'; @@ -1501,7 +1505,7 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) semantic_error("SRC@SRC is not allowed.\n"); return -EINVAL; } - pp->file = strdup(arg); + pp->file = strdup_esc(arg); if (pp->file == NULL) return -ENOMEM; break; @@ -2803,23 +2807,30 @@ static int find_probe_functions(struct map *map, char *name, struct rb_node *tmp; const char *norm, *ver; char *buf = NULL; + bool cut_version = true; if (map__load(map) < 0) return 0; + /* If user gives a version, don't cut off the version from symbols */ + if (strchr(name, '@')) + cut_version = false; + map__for_each_symbol(map, sym, tmp) { norm = arch__normalize_symbol_name(sym->name); if (!norm) continue; - /* We don't care about default symbol or not */ - ver = strchr(norm, '@'); - if (ver) { - buf = strndup(norm, ver - norm); - if (!buf) - return -ENOMEM; - norm = buf; + if (cut_version) { + /* We don't care about default symbol or not */ + ver = strchr(norm, '@'); + if (ver) { + buf = strndup(norm, ver - norm); + if (!buf) + return -ENOMEM; + norm = buf; } + if (strglobmatch(norm, name)) { found++; if (syms && found < probe_conf.max_probes) diff --git a/tools/perf/util/string.c b/tools/perf/util/string.c index aaa08ee8c717..d8bfd0c4d2cb 100644 --- a/tools/perf/util/string.c +++ b/tools/perf/util/string.c @@ -396,3 +396,49 @@ char *asprintf_expr_inout_ints(const char *var, bool in, size_t nints, int *ints free(expr); return NULL; } + +/* Like strpbrk(), but not break if it is right after a backslash (escaped) */ +char *strpbrk_esc(char *str, const char *stopset) +{ + char *ptr; + + do { + ptr = strpbrk(str, stopset); + if (ptr == str || + (ptr == str + 1 && *(ptr - 1) != '\\')) + break; + str = ptr + 1; + } while (ptr && *(ptr - 1) == '\\' && *(ptr - 2) != '\\'); + + return ptr; +} + +/* Like strdup, but do not copy a single backslash */ +char *strdup_esc(const char *str) +{ + char *s, *d, *p, *ret = strdup(str); + + if (!ret) + return NULL; + + d = strchr(ret, '\\'); + if (!d) + return ret; + + s = d + 1; + do { + if (*s == '\0') { + *d = '\0'; + break; + } + p = strchr(s + 1, '\\'); + if (p) { + memmove(d, s, p - s); + d += p - s; + s = p + 1; + } else + memmove(d, s, strlen(s) + 1); + } while (p); + + return ret; +} diff --git a/tools/perf/util/string2.h b/tools/perf/util/string2.h index ee14ca5451ab..4c68a09b97e8 100644 --- a/tools/perf/util/string2.h +++ b/tools/perf/util/string2.h @@ -39,5 +39,7 @@ static inline char *asprintf_expr_not_in_ints(const char *var, size_t nints, int return asprintf_expr_inout_ints(var, false, nints, ints); } +char *strpbrk_esc(char *str, const char *stopset); +char *strdup_esc(const char *str); #endif /* PERF_STRING_H */