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test: optimise fd closing in forks

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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 <kkanas@marvell.com>
Signed-off-by: David Marchand <david.marchand@redhat.com>
Tested-by: Krzysztof Kanas <kkanas@marvell.com>
Acked-by: Kevin Traynor <ktraynor@redhat.com>
This commit is contained in:
Krzysztof Kanas 2019-11-12 21:31:02 +01:00 committed by David Marchand
parent d25ab4b7f1
commit 18562261ab
1 changed files with 44 additions and 6 deletions
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50
app/test/process.h
View File

@ -11,6 +11,7 @@
#include <stdlib.h> /* NULL */
#include <string.h> /* strerror */
#include <unistd.h> /* readlink */
#include <dirent.h>
#include <sys/wait.h>
#include <rte_string_fns.h> /* 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]);