From 18562261abadfbdf7e19006c381bcb1d6fd6c2fe Mon Sep 17 00:00:00 2001 From: Krzysztof Kanas Date: Tue, 12 Nov 2019 21:31:02 +0100 Subject: [PATCH] test: optimise fd closing in forks Caught while investigating timeouts on a ARM64 server. Stracing a test process running the eal_flags_autotest, we can see that the fork helper is checking all possible file descriptors from getdtablesize() to 2, and close the existing ones. We can do better by inspecting this forked process /proc/self/fd directory. Besides, checking file descriptors via /proc/self/fd only makes sense for Linux. This code was a noop on FreeBSD. Fixes: af75078fece3 ("first public release") Cc: stable@dpdk.org Signed-off-by: Krzysztof Kanas Signed-off-by: David Marchand Tested-by: Krzysztof Kanas Acked-by: Kevin Traynor --- app/test/process.h | 50 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 44 insertions(+), 6 deletions(-) diff --git a/app/test/process.h b/app/test/process.h index 128ce41219..191d2796a9 100644 --- a/app/test/process.h +++ b/app/test/process.h @@ -11,6 +11,7 @@ #include /* NULL */ #include /* strerror */ #include /* readlink */ +#include #include #include /* strlcpy */ @@ -40,7 +41,7 @@ process_dup(const char *const argv[], int numargs, const char *env_value) { int num; char *argv_cpy[numargs + 1]; - int i, fd, status; + int i, status; char path[32]; #ifdef RTE_LIBRTE_PDUMP pthread_t thread; @@ -56,13 +57,50 @@ process_dup(const char *const argv[], int numargs, const char *env_value) argv_cpy[i] = NULL; num = numargs; - /* close all open file descriptors, check /proc/self/fd to only - * call close on open fds. Exclude fds 0, 1 and 2*/ - for (fd = getdtablesize(); fd > 2; fd-- ) { - snprintf(path, sizeof(path), "/proc/" exe "/fd/%d", fd); - if (access(path, F_OK) == 0) +#ifdef RTE_EXEC_ENV_LINUX + { + const char *procdir = "/proc/" self "/fd/"; + struct dirent *dirent; + char *endptr; + int fd, fdir; + DIR *dir; + + /* close all open file descriptors, check /proc/self/fd + * to only call close on open fds. Exclude fds 0, 1 and + * 2 + */ + dir = opendir(procdir); + if (dir == NULL) { + rte_panic("Error opening %s: %s\n", procdir, + strerror(errno)); + } + + fdir = dirfd(dir); + if (fdir < 0) { + status = errno; + closedir(dir); + rte_panic("Error %d obtaining fd for dir %s: %s\n", + fdir, procdir, + strerror(status)); + } + + while ((dirent = readdir(dir)) != NULL) { + errno = 0; + fd = strtol(dirent->d_name, &endptr, 10); + if (errno != 0 || endptr[0] != '\0') { + printf("Error converting name fd %d %s:\n", + fd, dirent->d_name); + continue; + } + + if (fd == fdir || fd <= 2) + continue; + close(fd); + } + closedir(dir); } +#endif printf("Running binary with argv[]:"); for (i = 0; i < num; i++) printf("'%s' ", argv_cpy[i]); -- 2.20.1