Re: [PATCH] selftest: add a test case to check how locks are shown in fdinfo

[Shuah Khan <shuahkh@osg.samsung.com>]

On 03/13/2015 03:34 AM, Andrew Vagin wrote:
> On Thu, Mar 12, 2015 at 02:43:19PM -0600, Shuah Khan wrote:
>> Hi Andrey,
>>
>> Looks good in general. Couple of comments.
> 
> Thanks. The updated version is attached.

Please send a properly marked patch v2. Please don't
send patches as attachments.

thanks,
-- Shuah
> 
>>
>> On 03/12/2015 10:30 AM, Andrey Vagin wrote:
>>> The main idea of this test is to check that locks are shown correctly
>>> when they can't be placed in a default seq_file buffer due to its size.
>>>
>>> Cc: Andrew Morton <akpm@linux-foundation.org>
>>> Cc: Shuah Khan <shuahkh@osg.samsung.com>
>>> Signed-off-by: Andrey Vagin <avagin@openvz.org>
>>> ---
>>>  tools/testing/selftests/Makefile        |   1 +
>>>  tools/testing/selftests/fdinfo/Makefile |  11 +++
>>>  tools/testing/selftests/fdinfo/locks.c  | 119 ++++++++++++++++++++++++++++++++
>>>  3 files changed, 131 insertions(+)
>>>  create mode 100644 tools/testing/selftests/fdinfo/Makefile
>>>  create mode 100644 tools/testing/selftests/fdinfo/locks.c
>>>
>>> diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
>>> index 4e51122..8cd57f6 100644
>>> --- a/tools/testing/selftests/Makefile
>>> +++ b/tools/testing/selftests/Makefile
>>> @@ -17,6 +17,7 @@ TARGETS += sysctl
>>>  TARGETS += timers
>>>  TARGETS += user
>>>  TARGETS += vm
>>> +TARGETS += fdinfo
>>>  #Please keep the TARGETS list alphabetically sorted
>>
>> Please move the new target up to keep the TARGETS list
>> alphabetically sorted. This helps avoid conflicts as new
>> tests get added.
>>
>>>  
>>>  TARGETS_HOTPLUG = cpu-hotplug
>>> diff --git a/tools/testing/selftests/fdinfo/Makefile b/tools/testing/selftests/fdinfo/Makefile
>>> new file mode 100644
>>> index 0000000..83f34ef
>>> --- /dev/null
>>> +++ b/tools/testing/selftests/fdinfo/Makefile
>>> @@ -0,0 +1,11 @@
>>> +CFLAGS += -Wall
>>> +
>>> +all: locks
>>> +
>>> +run_tests: all
>>> +	@./locks || echo "locks: [FAIL]"
>>> +
>>> +locks: locks.c
>>> +
>>> +clean:
>>> +	rm -f locks
>>> diff --git a/tools/testing/selftests/fdinfo/locks.c b/tools/testing/selftests/fdinfo/locks.c
>>> new file mode 100644
>>> index 0000000..93f25c6
>>> --- /dev/null
>>> +++ b/tools/testing/selftests/fdinfo/locks.c
>>> @@ -0,0 +1,119 @@
>>> +#include <stdlib.h>
>>> +#include <stdio.h>
>>> +#include <unistd.h>
>>> +#include <string.h>
>>> +#include <sys/types.h>
>>> +#include <sys/stat.h>
>>> +#include <fcntl.h>
>>> +
>>> +#define pr_perror(fmt, ...) fprintf(stderr, "%s:%d: " fmt ": %m\n", \
>>> +					__FILE__, __LINE__, ##__VA_ARGS__)
>>> +
>>> +#define FILE_SIZE 4096
>>> +
>>> +int main(int argc, char **argv)
>>> +{
>>> +	int fd, fdinfo, i, ret, size, bsize = 4096;
>>> +	char *buf, *p, fdinfo_path[] = "/proc/self/fdinfo/XXXXXXXXXX";
>>> +
>>> +	fd = open("test_file", O_RDWR | O_CREAT, 0666);
>>> +	if (fd == -1) {
>>> +		pr_perror("Unable to open test_file");
>>> +		return 1;
>>> +	}
>>> +	unlink("test_file");
>>> +	if (ftruncate(fd, FILE_SIZE) == -1) {
>>> +		pr_perror("Unable to truncate test_file");
>>> +		return 1;
>>> +	}
>>> +
>>> +	/*
>>> +	 * Generate FILE_SIZE locks. We are going to exceed the default
>>> +	 * size of seq buffer
>>> +	 */
>>> +	for (i = 0; i < FILE_SIZE; i++) {
>>> +		struct flock lock;
>>> +
>>> +		if (i % 2)
>>> +			lock.l_type = F_WRLCK;
>>> +		else
>>> +			lock.l_type = F_RDLCK;
>>> +		lock.l_whence = SEEK_SET;
>>> +		lock.l_start  = i;
>>> +		lock.l_len    = 1;
>>> +		lock.l_pid    = -1;
>>> +		if (fcntl(fd, F_SETLK, &lock)) {
>>> +			pr_perror("Unable to set lock %d\n", i);
>>> +			return 1;
>>> +		}
>>> +	}
>>> +
>>> +	snprintf(fdinfo_path, sizeof(fdinfo_path), "/proc/self/fdinfo/%d", fd);
>>> +	fdinfo = open(fdinfo_path, O_RDONLY);
>>> +	if (fdinfo < 0) {
>>> +		pr_perror("Unable to open %s", fdinfo_path);
>>> +		return 1;
>>> +	}
>>> +
>>> +	buf = malloc(bsize);
>>> +	if (buf == NULL) {
>>> +		pr_perror("Unable to allocate a buffer");
>>> +		return 1;
>>> +	}
>>> +	size = 0;
>>> +	while (1) {
>>> +		ret = read(fdinfo, buf + size, bsize - 1 - size);
>>> +		if (ret == 0)
>>> +			break;
>>> +		if (ret == -1) {
>>> +			pr_perror("Unable to read %s", fdinfo_path);
>>> +			return 1;
>>> +		}
>>> +		size += ret;
>>> +		if (bsize - size < 4096)
>>> +			bsize += 4096;
>>> +		buf = realloc(buf, bsize);
>>> +		if (buf == NULL) {
>>> +			pr_perror("Unable to allocate a buffer");
>>> +			return 1;
>>> +		}
>>> +	}
>>> +	buf[size] = 0;
>>> +
>>> +	i = 0;
>>> +	for (p = buf - 1; p != NULL; p = strchr(p, '\n')) {
>>> +		char fl_flag[10], fl_type[15], fl_option[10], end[32];
>>> +		int fl_id, fl_owner, maj, min;
>>> +		unsigned long ino;
>>> +		unsigned long long start;
>>> +
>>> +		p++;
>>> +
>>> +		if (strncmp(p, "lock:", 5))
>>> +			continue;
>>> +		ret = sscanf(p, "lock:\t%d:%s %s %s %d %x:%x:%ld %lld %s",
>>> +				&fl_id, fl_flag, fl_type, fl_option,
>>> +				&fl_owner, &maj, &min, &ino,
>>> +				&start, end);
>>> +		if (ret != 10) {
>>> +			pr_perror("Unable to parse");
>>> +			fprintf(stderr, "%s\n", buf);
>>> +			return 1;
>>> +		}
>>> +		i++;
>>> +	}
>>> +
>>> +	close(fdinfo);
>>> +	close(fd);
>>> +
>>> +	if (i == FILE_SIZE)
>>> +		printf("PASS\n");
>>
>> Look into using ksft framework for reporting pass/fail conditions.
>> Please see kselftest.h for the framework.
>>
>>> +	else {
>>> +		fprintf(stderr, "%s\n", buf);
>>> +		return 1;
>>> +	}
>>> +
>>> +	free(buf);
>>> +
>>> +	return 0;
>>> +}
>>>
>>
>> thanks,
>> -- Shuah
>>
>> -- 
>> Shuah Khan
>> Sr. Linux Kernel Developer
>> Open Source Innovation Group
>> Samsung Research America (Silicon Valley)
>> shuahkh@osg.samsung.com | (970) 217-8978


-- 
Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America (Silicon Valley)
shuahkh@osg.samsung.com | (970) 217-8978