svn commit: r353305 - head/tests/sys/kern

[Konstantin Belousov]

On Tue, Oct 08, 2019 at 01:43:05PM +0000, Eric van Gyzen wrote:
> Author: vangyzen
> Date: Tue Oct  8 13:43:05 2019
> New Revision: 353305
> URL: https://svnweb.freebsd.org/changeset/base/353305
> 
> Log:
>   Fix problems in the kern_maxfiles__increase test
>   
>   ATF functions such as ATF_REQUIRE do not work correctly in child processes.
>   Use plain C functions to report errors instead.
There are much more tests that fork and use ATF_ in children.
Look e.g. at most ptrace(2) tests.

>   
>   In the parent, check for the untimely demise of children.  Without this,
>   the test hung until the framework's timeout.
>   
>   Raise the resource limit on the number of open files.  If this was too low,
>   the test hit the two problems above.
>   
>   Restore the kern.maxfiles sysctl OID in the cleanup function.
>   The body prematurely removed the symlink in which the old value was saved.
>   
>   Make the test more robust by opening more files.  In fact, due to the
>   integer division by 4, this was necessary to make the test valid with
>   some initial values of maxfiles.  Thanks, asomers at .
>   
>   wait() for children instead of sleeping.
>   
>   Clean up a temporary file created by the test ("afile").
>   
>   Reviewed by:	asomers
>   MFC after:	1 week
>   Sponsored by:	Dell EMC Isilon
>   Differential Revision:	https://reviews.freebsd.org/D21900
> 
> Modified:
>   head/tests/sys/kern/kern_descrip_test.c
> 
> Modified: head/tests/sys/kern/kern_descrip_test.c
> ==============================================================================
> --- head/tests/sys/kern/kern_descrip_test.c	Tue Oct  8 11:27:48 2019	(r353304)
> +++ head/tests/sys/kern/kern_descrip_test.c	Tue Oct  8 13:43:05 2019	(r353305)
> @@ -28,16 +28,22 @@
>  __FBSDID("$FreeBSD$");
>  
>  #include <sys/param.h>
> +#include <sys/limits.h>
> +#include <sys/resource.h>
> +#include <sys/stat.h>
> +#include <sys/sysctl.h>
> +#include <sys/time.h>
> +#include <sys/wait.h>
> +
>  #include <errno.h>
>  #include <fcntl.h>
>  #include <signal.h>
>  #include <stdio.h>
>  #include <stdlib.h>
> +#include <string.h>
>  #include <strings.h>
> -#include <sys/limits.h>
> -#include <sys/stat.h>
> -#include <sys/sysctl.h>
>  #include <unistd.h>
> +
>  #include <atf-c.h>
>  
>  static volatile sig_atomic_t done;
> @@ -92,8 +98,13 @@ openfiles2(size_t n)
>  	int r;
>  
>  	errno = 0;
> -	for (i = 0; i < n; i++)
> -		ATF_REQUIRE((r = open(AFILE, O_RDONLY)) != -1);
> +	for (i = 0; i < n; i++) {
> +		r = open(AFILE, O_RDONLY);
> +		if (r < 0) {
> +			fprintf(stderr, "open: %s\n", strerror(errno));
> +			_exit(1);
> +		}
> +	}
>  	kill(getppid(), SIGUSR1);
>  
>  	for (;;) {
> @@ -118,10 +129,14 @@ openfiles(size_t n)
>  	for (i = 0; i < PARALLEL; i++)
>  		if (fork() == 0)
>  			openfiles2(n / PARALLEL);
> -	while (done != PARALLEL)
> +	while (done != PARALLEL) {
>  		usleep(1000);
> +		ATF_REQUIRE_EQ_MSG(0, waitpid(-1, NULL, WNOHANG),
> +			"a child exited unexpectedly");
> +	}
>  	unlink(RENDEZVOUS);
> -	usleep(40000);
> +	for (i = 0; i < PARALLEL; i++)
> +		ATF_CHECK_MSG(wait(NULL) > 0, "wait: %s", strerror(errno));
>  }
>  
>  ATF_TC_WITH_CLEANUP(kern_maxfiles__increase);
> @@ -138,6 +153,7 @@ ATF_TC_BODY(kern_maxfiles__increase, tc)
>  	size_t oldlen;
>  	int maxfiles, oldmaxfiles, current;
>  	char buf[80];
> +	struct rlimit rl;
>  
>  	oldlen = sizeof(maxfiles);
>  	if (sysctlbyname("kern.maxfiles", &maxfiles, &oldlen, NULL, 0) == -1)
> @@ -160,8 +176,11 @@ ATF_TC_BODY(kern_maxfiles__increase, tc)
>  		atf_tc_fail("getsysctlbyname(%s): %s", "kern.maxfiles",
>  		    strerror(errno));
>  
> -	openfiles(oldmaxfiles - current + 1);
> -	(void)unlink(VALUE);
> +	rl.rlim_cur = rl.rlim_max = maxfiles;
> +	ATF_REQUIRE_EQ_MSG(0, setrlimit(RLIMIT_NOFILE, &rl),
> +		"setrlimit(RLIMIT_NOFILE, %d): %s", maxfiles, strerror(errno));
> +
> +	openfiles(oldmaxfiles - current + EXPANDBY / 2);
>  }
>  
>  ATF_TC_CLEANUP(kern_maxfiles__increase, tc)
> @@ -178,6 +197,8 @@ ATF_TC_CLEANUP(kern_maxfiles__increase, tc)
>  			    &oldmaxfiles, oldlen);
>  		}
>  	}
> +	(void)unlink(VALUE);
> +	(void)unlink(AFILE);
>  }
>  
>  ATF_TP_ADD_TCS(tp)