From: Ian Rogers Date: Mon, 3 Apr 2023 18:40:32 +0000 (-0700) Subject: perf srcline: Support for llvm-addr2line X-Git-Tag: v6.4-rc1~1^2~158 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=2c4b928074839425b64155cb3f6d4e0e5e67e835;p=linux-block.git perf srcline: Support for llvm-addr2line The sentinel value differs for llvm-addr2line. Configure this once and then detect when reading records. Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mark Rutland Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Tom Rix Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230403184033.1836023-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c index 5339ab4c5e12..f4fcdada821b 100644 --- a/tools/perf/util/srcline.c +++ b/tools/perf/util/srcline.c @@ -435,7 +435,50 @@ static struct child_process *addr2line_subprocess_init(const char *addr2line_pat return a2l; } +enum a2l_style { + BROKEN, + GNU_BINUTILS, + LLVM, +}; + +static enum a2l_style addr2line_configure(struct child_process *a2l) +{ + static bool cached; + static enum a2l_style style; + + if (!cached) { + char buf[128]; + struct io io; + int ch; + + if (write(a2l->in, ",\n", 2) != 2) + return BROKEN; + + io__init(&io, a2l->out, buf, sizeof(buf)); + ch = io__get_char(&io); + if (ch == ',') { + style = LLVM; + cached = true; + } else if (ch == '?') { + style = GNU_BINUTILS; + cached = true; + } else { + style = BROKEN; + } + do { + ch = io__get_char(&io); + } while (ch > 0 && ch != '\n'); + if (style == GNU_BINUTILS) { + do { + ch = io__get_char(&io); + } while (ch > 0 && ch != '\n'); + } + } + return style; +} + static int read_addr2line_record(struct io *io, + enum a2l_style style, char **function, char **filename, unsigned int *line_nr) @@ -462,6 +505,12 @@ static int read_addr2line_record(struct io *io, if (io__getline(io, &line, &line_len) < 0 || !line_len) goto error; + + if (style == LLVM && line_len == 2 && line[0] == ',') { + zfree(&line); + return 0; + } + if (function != NULL) *function = strdup(strim(line)); @@ -471,7 +520,8 @@ static int read_addr2line_record(struct io *io, if (io__getline(io, &line, &line_len) < 0 || !line_len) goto error; - if (filename_split(line, line_nr == NULL ? &dummy_line_nr : line_nr) == 0) { + if (filename_split(line, line_nr == NULL ? &dummy_line_nr : line_nr) == 0 && + style == GNU_BINUTILS) { ret = 0; goto error; } @@ -523,6 +573,7 @@ static int addr2line(const char *dso_name, u64 addr, char buf[128]; ssize_t written; struct io io; + enum a2l_style a2l_style; if (!a2l) { if (!filename__has_section(dso_name, ".debug_line")) @@ -538,15 +589,22 @@ static int addr2line(const char *dso_name, u64 addr, pr_warning("%s %s: addr2line_subprocess_init failed\n", __func__, dso_name); goto out; } + a2l_style = addr2line_configure(a2l); + if (a2l_style == BROKEN) { + if (!symbol_conf.disable_add2line_warn) + pr_warning("%s: addr2line configuration failed\n", __func__); + goto out; + } /* * Send our request and then *deliberately* send something that can't be interpreted as * a valid address to ask addr2line about (namely, ","). This causes addr2line to first * write out the answer to our request, in an unbounded/unknown number of records, and - * then to write out the lines "??" and "??:0", so that we can detect when it has - * finished giving us anything useful. We have to be careful about the first record, - * though, because it may be genuinely unknown, in which case we'll get two sets of - * "??"/"??:0" lines. + * then to write out the lines "??" and "??:0", for GNU binutils, or "," for + * llvm-addr2line, so that we can detect when it has finished giving us anything + * useful. With GNU binutils, we have to be careful about the first record, though, + * because it may be genuinely unknown, in which case we'll get two sets of "??"/"??:0" + * lines. */ len = snprintf(buf, sizeof(buf), "%016"PRIx64"\n,\n", addr); written = len > 0 ? write(a2l->in, buf, len) : -1; @@ -557,7 +615,8 @@ static int addr2line(const char *dso_name, u64 addr, } io__init(&io, a2l->out, buf, sizeof(buf)); - switch (read_addr2line_record(&io, &record_function, &record_filename, &record_line_nr)) { + switch (read_addr2line_record(&io, a2l_style, + &record_function, &record_filename, &record_line_nr)) { case -1: if (!symbol_conf.disable_add2line_warn) pr_warning("%s %s: could not read first record\n", __func__, dso_name); @@ -567,7 +626,7 @@ static int addr2line(const char *dso_name, u64 addr, * The first record was invalid, so return failure, but first read another * record, since we asked a junk question and have to clear the answer out. */ - switch (read_addr2line_record(&io, NULL, NULL, NULL)) { + switch (read_addr2line_record(&io, a2l_style, NULL, NULL, NULL)) { case -1: if (!symbol_conf.disable_add2line_warn) pr_warning("%s %s: could not read delimiter record\n", @@ -606,6 +665,7 @@ static int addr2line(const char *dso_name, u64 addr, /* We have to read the records even if we don't care about the inline info. */ while ((record_status = read_addr2line_record(&io, + a2l_style, &record_function, &record_filename, &record_line_nr)) == 1) {