From 4235949944d1bb244c85fd184cdc2f78e9df848b Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Thu, 10 Oct 2019 11:36:46 -0700 Subject: [PATCH] perf annotate: Use libsubcmd's run-command.h to fork objdump Reduce duplicated logic by using the subcmd library. Ensure when errors occur they are reported to the caller. Before this patch, if no lines are read the error status is 0. Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Jin Yao Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Song Liu Cc: Stephane Eranian Cc: clang-built-linux@googlegroups.com Link: http://lore.kernel.org/lkml/20191010183649.23768-3-irogers@google.com Link: http://lore.kernel.org/lkml/20191015003418.62563-1-irogers@google.com [ merged follow up fix for NULL termination as in the 2nd link above ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/annotate.c | 72 ++++++++++++++++++++------------------ 1 file changed, 37 insertions(+), 35 deletions(-) diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c index f9c39a742418..9835666db5a7 100644 --- a/tools/perf/util/annotate.c +++ b/tools/perf/util/annotate.c @@ -43,6 +43,7 @@ #include #include #include +#include /* FIXME: For the HE_COLORSET */ #include "ui/browser.h" @@ -1864,12 +1865,19 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) struct kcore_extract kce; bool delete_extract = false; bool decomp = false; - int stdout_fd[2]; int lineno = 0; int nline; - pid_t pid; char *line; size_t line_len; + const char *objdump_argv[] = { + "/bin/sh", + "-c", + NULL, /* Will be the objdump command to run. */ + "--", + NULL, /* Will be the symfs path. */ + NULL, + }; + struct child_process objdump_process; int err = dso__disassemble_filename(dso, symfs_filename, sizeof(symfs_filename)); if (err) @@ -1899,7 +1907,7 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) if (dso__decompress_kmodule_path(dso, symfs_filename, tmp, sizeof(tmp)) < 0) - goto out; + return -1; decomp = true; strcpy(symfs_filename, tmp); @@ -1924,38 +1932,28 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) pr_debug("Executing: %s\n", command); - err = -1; - if (pipe(stdout_fd) < 0) { - pr_err("Failure creating the pipe to run %s\n", command); - goto out_free_command; - } - - pid = fork(); - if (pid < 0) { - pr_err("Failure forking to run %s\n", command); - goto out_close_stdout; - } + objdump_argv[2] = command; + objdump_argv[4] = symfs_filename; - if (pid == 0) { - close(stdout_fd[0]); - dup2(stdout_fd[1], 1); - close(stdout_fd[1]); - execl("/bin/sh", "sh", "-c", command, "--", symfs_filename, - NULL); - perror(command); - exit(-1); + /* Create a pipe to read from for stdout */ + memset(&objdump_process, 0, sizeof(objdump_process)); + objdump_process.argv = objdump_argv; + objdump_process.out = -1; + if (start_command(&objdump_process)) { + pr_err("Failure starting to run %s\n", command); + err = -1; + goto out_free_command; } - close(stdout_fd[1]); - - file = fdopen(stdout_fd[0], "r"); + file = fdopen(objdump_process.out, "r"); if (!file) { pr_err("Failure creating FILE stream for %s\n", command); /* * If we were using debug info should retry with * original binary. */ - goto out_free_command; + err = -1; + goto out_close_stdout; } /* Storage for getline. */ @@ -1979,8 +1977,14 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) } free(line); - if (nline == 0) + err = finish_command(&objdump_process); + if (err) + pr_err("Error running %s\n", command); + + if (nline == 0) { + err = -1; pr_err("No output from %s\n", command); + } /* * kallsyms does not have symbol sizes so there may a nop at the end. @@ -1990,23 +1994,21 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) delete_last_nop(sym); fclose(file); - err = 0; + +out_close_stdout: + close(objdump_process.out); + out_free_command: free(command); -out_remove_tmp: - close(stdout_fd[0]); +out_remove_tmp: if (decomp) unlink(symfs_filename); if (delete_extract) kcore_extract__delete(&kce); -out: - return err; -out_close_stdout: - close(stdout_fd[1]); - goto out_free_command; + return err; } static void calc_percent(struct sym_hist *sym_hist, -- 2.30.2