[CRIU] [PATCH 1/2] zdtm: Make file_locks04 test based on /proc/{pid}/fdinfo/{fd}

[Andrew Vagin]

On Tue, Jun 28, 2016 at 09:06:30PM +0300, Kirill Tkhai wrote:
> 
> 
> On 28.06.2016 21:02, Andrew Vagin wrote:
> > On Tue, Jun 28, 2016 at 08:49:04PM +0300, Kirill Tkhai wrote:
> >> /proc/locks is racy with adding/removing locks,
> >> so we may lose test lock on a check.
> >>
> >> Use fdinfo list of locks instead.
> > 
> > fdinfo contains locks starting with the 4.1 kernel, how this test will
> > work on older kernels?
> > 
> > What is about other file_locks* tests?
> 
> They should be fixed as well if they need.

Could you fix them too and remove the excl flag from desc files?

>  
> >>
> >> Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
> >> ---
> >>  test/zdtm/static/file_locks04.c |   32 ++++++++++++++++++--------------
> >>  1 file changed, 18 insertions(+), 14 deletions(-)
> >>
> >> diff --git a/test/zdtm/static/file_locks04.c b/test/zdtm/static/file_locks04.c
> >> index 995dd09..dfb7c53 100644
> >> --- a/test/zdtm/static/file_locks04.c
> >> +++ b/test/zdtm/static/file_locks04.c
> >> @@ -6,6 +6,7 @@
> >>  #include <unistd.h>
> >>  #include <sys/file.h>
> >>  #include <string.h>
> >> +#include <limits.h>
> >>  #include <sys/wait.h>
> >>  
> >>  #include "zdtmtst.h"
> >> @@ -16,27 +17,27 @@ const char *test_author	= "Pavel Emelyanov <xemul at parallels.com>";
> >>  char *filename;
> >>  TEST_OPTION(filename, string, "file name", 1);
> >>  
> >> -static int check_file_locks(int alt_pid, int fd)
> >> +static int check_file_locks(pid_t child_pid, int fd, int child_fd)
> >>  {
> >> +	char		path[PATH_MAX];
> >>  	FILE		*fp_locks = NULL;
> >>  	char		buf[100], fl_flag[16], fl_type[16], fl_option[16];
> >> -	pid_t		pid = getpid();
> >>  	int		found = 0, num, fl_owner;
> >>  
> >> -	fp_locks = fopen("/proc/locks", "r");
> >> -	if (!fp_locks)
> >> +	sprintf(path, "/proc/%d/fdinfo/%d", child_pid, child_fd);
> >> +	fp_locks = fopen(path, "r");
> >> +	if (!fp_locks) {
> >> +		pr_err("Can't open %s\n", path);
> >>  		return -1;
> >> -
> >> -	test_msg("C: %d/%d\n", pid, alt_pid);
> >> +	}
> >>  
> >>  	while (fgets(buf, sizeof(buf), fp_locks)) {
> >> -		test_msg("c: %s", buf);
> >> -
> >> -		if (strstr(buf, "->"))
> >> +		if (strncmp(buf, "lock:\t", 6) != 0)
> >>  			continue;
> >> +		test_msg("c: %s", buf);
> >>  
> >>  		num = sscanf(buf,
> >> -			"%*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
> >> +			"%*s %*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
> >>  			fl_flag, fl_type, fl_option, &fl_owner);
> >>  
> >>  		if (num < 4) {
> >> @@ -44,8 +45,10 @@ static int check_file_locks(int alt_pid, int fd)
> >>  			break;
> >>  		}
> >>  
> >> -		if (fl_owner != pid && fl_owner != alt_pid)
> >> +		if (fl_owner != child_pid && fl_owner != getpid()) {
> >> +			pr_err("Wrong owner\n");
> >>  			continue;
> >> +		}
> >>  
> >>  		if (!strcmp(fl_flag, "FLOCK") &&
> >>  				!strcmp(fl_type, "ADVISORY") &&
> >> @@ -67,11 +70,11 @@ static int check_file_locks(int alt_pid, int fd)
> >>  
> >>  int main(int argc, char **argv)
> >>  {
> >> -	int fd, pid;
> >> +	int fd, child_fd, pid, ret;
> >>  
> >>  	test_init(argc, argv);
> >>  
> >> -	fd = open(filename, O_CREAT | O_RDWR, 0600);
> >> +	fd = child_fd = open(filename, O_CREAT | O_RDWR, 0600);
> >>  	if (fd < 0) {
> >>  		pr_perror("No file");
> >>  		return -1;
> >> @@ -105,11 +108,12 @@ int main(int argc, char **argv)
> >>  	test_daemon();
> >>  	test_waitsig();
> >>  
> >> -	if (check_file_locks(pid, fd))
> >> +	if (check_file_locks(pid, fd, child_fd) > 0)
> >>  		pass();
> >>  	else
> >>  		fail("Flock file locks check failed");
> >>  
> >> +out_kill:
> >>  	kill(pid, SIGTERM);
> >>  	waitpid(pid, NULL, 0);
> >>  	close(fd);
> >>