[PATCH] selftest: add a test case to check how locks are shown in fdinfo (v2)

From: Andrey Vagin
Date: Thu Mar 12 2015 - 08:28:55 EST


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.

V2: use the kselftest framework

Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
Signed-off-by: Andrey Vagin <avagin@xxxxxxxxxx>
---
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..061a507 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -2,6 +2,7 @@ TARGETS = breakpoints
TARGETS += cpu-hotplug
TARGETS += efivarfs
TARGETS += exec
+TARGETS += fdinfo
TARGETS += firmware
TARGETS += ftrace
TARGETS += kcmp
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..71fc237
--- /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>
+
+#include "../kselftest.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 ksft_exit_fail();
+ }
+ unlink("test_file");
+ if (ftruncate(fd, FILE_SIZE) == -1) {
+ pr_perror("Unable to truncate test_file");
+ return ksft_exit_fail();
+ }
+
+ /*
+ * 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 ksft_exit_fail();
+ }
+ }
+
+ 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 ksft_exit_fail();
+ }
+
+ buf = malloc(bsize);
+ if (buf == NULL) {
+ pr_perror("Unable to allocate a buffer");
+ return ksft_exit_fail();
+ }
+ 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 ksft_exit_fail();
+ }
+ size += ret;
+ if (bsize - size < 4096)
+ bsize += 4096;
+ buf = realloc(buf, bsize);
+ if (buf == NULL) {
+ pr_perror("Unable to allocate a buffer");
+ return ksft_exit_fail();
+ }
+ }
+ 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 ksft_exit_fail();
+ }
+ i++;
+ }
+
+ close(fdinfo);
+ close(fd);
+
+ if (i != FILE_SIZE) {
+ fprintf(stderr, "%s\n", buf);
+ return ksft_exit_fail();
+ }
+
+ free(buf);
+
+ return ksft_exit_pass();
+}
--
2.1.0


--k1lZvvs/B4yU6o8G--
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