[RESEDN PATCH v2] selftests: introduce additional eventfd test coverage
From: Wen Yang
Date: Sun May 26 2024 - 20:02:58 EST
Add several new test cases which assert corner cases on the eventfd
mechanism, for example, the supplied buffer is less than 8 bytes,
attempting to write a value that is too large, etc.
./eventfd_test
# Starting 9 tests from 1 test cases.
# RUN global.eventfd_check_flag_rdwr ...
# OK global.eventfd_check_flag_rdwr
ok 1 global.eventfd_check_flag_rdwr
# RUN global.eventfd_check_flag_cloexec ...
# OK global.eventfd_check_flag_cloexec
ok 2 global.eventfd_check_flag_cloexec
# RUN global.eventfd_check_flag_nonblock ...
# OK global.eventfd_check_flag_nonblock
ok 3 global.eventfd_check_flag_nonblock
# RUN global.eventfd_chek_flag_cloexec_and_nonblock ...
# OK global.eventfd_chek_flag_cloexec_and_nonblock
ok 4 global.eventfd_chek_flag_cloexec_and_nonblock
# RUN global.eventfd_check_flag_semaphore ...
# OK global.eventfd_check_flag_semaphore
ok 5 global.eventfd_check_flag_semaphore
# RUN global.eventfd_check_write ...
# OK global.eventfd_check_write
ok 6 global.eventfd_check_write
# RUN global.eventfd_check_read ...
# OK global.eventfd_check_read
ok 7 global.eventfd_check_read
# RUN global.eventfd_check_read_with_nonsemaphore ...
# OK global.eventfd_check_read_with_nonsemaphore
ok 8 global.eventfd_check_read_with_nonsemaphore
# RUN global.eventfd_check_read_with_semaphore ...
# OK global.eventfd_check_read_with_semaphore
ok 9 global.eventfd_check_read_with_semaphore
# PASSED: 9 / 9 tests passed.
# Totals: pass:9 fail:0 xfail:0 xpass:0 skip:0 error:0
Signed-off-by: Wen Yang <wen.yang@xxxxxxxxx>
Cc: SShuah Khan <shuah@xxxxxxxxxx>
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Andrei Vagin <avagin@xxxxxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Dave Young <dyoung@xxxxxxxxxx>
Cc: Tim Bird <tim.bird@xxxxxxxx>
Cc: linux-kselftest@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
v2: use strings which indicate what is being tested, that are useful to a human
.../filesystems/eventfd/eventfd_test.c | 136 +++++++++++++++++-
1 file changed, 131 insertions(+), 5 deletions(-)
diff --git a/tools/testing/selftests/filesystems/eventfd/eventfd_test.c b/tools/testing/selftests/filesystems/eventfd/eventfd_test.c
index f142a137526c..85acb4e3ef00 100644
--- a/tools/testing/selftests/filesystems/eventfd/eventfd_test.c
+++ b/tools/testing/selftests/filesystems/eventfd/eventfd_test.c
@@ -13,6 +13,8 @@
#include <sys/eventfd.h>
#include "../../kselftest_harness.h"
+#define EVENTFD_TEST_ITERATIONS 100000UL
+
struct error {
int code;
char msg[512];
@@ -40,7 +42,7 @@ static inline int sys_eventfd2(unsigned int count, int flags)
return syscall(__NR_eventfd2, count, flags);
}
-TEST(eventfd01)
+TEST(eventfd_check_flag_rdwr)
{
int fd, flags;
@@ -54,7 +56,7 @@ TEST(eventfd01)
close(fd);
}
-TEST(eventfd02)
+TEST(eventfd_check_flag_cloexec)
{
int fd, flags;
@@ -68,7 +70,7 @@ TEST(eventfd02)
close(fd);
}
-TEST(eventfd03)
+TEST(eventfd_check_flag_nonblock)
{
int fd, flags;
@@ -83,7 +85,7 @@ TEST(eventfd03)
close(fd);
}
-TEST(eventfd04)
+TEST(eventfd_chek_flag_cloexec_and_nonblock)
{
int fd, flags;
@@ -161,7 +163,7 @@ static int verify_fdinfo(int fd, struct error *err, const char *prefix,
return 0;
}
-TEST(eventfd05)
+TEST(eventfd_check_flag_semaphore)
{
struct error err = {0};
int fd, ret;
@@ -183,4 +185,128 @@ TEST(eventfd05)
close(fd);
}
+/*
+ * A write(2) fails with the error EINVAL if the size of the supplied buffer
+ * is less than 8 bytes, or if an attempt is made to write the value
+ * 0xffffffffffffffff.
+ */
+TEST(eventfd_check_write)
+{
+ uint64_t value = 1;
+ ssize_t size;
+ int fd;
+
+ fd = sys_eventfd2(0, 0);
+ ASSERT_GE(fd, 0);
+
+ size = write(fd, &value, sizeof(int));
+ EXPECT_EQ(size, -1);
+ EXPECT_EQ(errno, EINVAL);
+
+ size = write(fd, &value, sizeof(value));
+ EXPECT_EQ(size, sizeof(value));
+
+ value = (uint64_t)-1;
+ size = write(fd, &value, sizeof(value));
+ EXPECT_EQ(size, -1);
+ EXPECT_EQ(errno, EINVAL);
+
+ close(fd);
+}
+
+/*
+ * A read(2) fails with the error EINVAL if the size of the supplied buffer is
+ * less than 8 bytes.
+ */
+TEST(eventfd_check_read)
+{
+ uint64_t value;
+ ssize_t size;
+ int fd;
+
+ fd = sys_eventfd2(1, 0);
+ ASSERT_GE(fd, 0);
+
+ size = read(fd, &value, sizeof(int));
+ EXPECT_EQ(size, -1);
+ EXPECT_EQ(errno, EINVAL);
+
+ size = read(fd, &value, sizeof(value));
+ EXPECT_EQ(size, sizeof(value));
+ EXPECT_EQ(value, 1);
+
+ close(fd);
+}
+
+
+/*
+ * If EFD_SEMAPHORE was not specified and the eventfd counter has a nonzero
+ * value, then a read(2) returns 8 bytes containing that value, and the
+ * counter's value is reset to zero.
+ * If the eventfd counter is zero at the time of the call to read(2), then the
+ * call fails with the error EAGAIN if the file descriptor has been made nonblocking.
+ */
+TEST(eventfd_check_read_with_nonsemaphore)
+{
+ uint64_t value;
+ ssize_t size;
+ int fd;
+ int i;
+
+ fd = sys_eventfd2(0, EFD_NONBLOCK);
+ ASSERT_GE(fd, 0);
+
+ value = 1;
+ for (i = 0; i < EVENTFD_TEST_ITERATIONS; i++) {
+ size = write(fd, &value, sizeof(value));
+ EXPECT_EQ(size, sizeof(value));
+ }
+
+ size = read(fd, &value, sizeof(value));
+ EXPECT_EQ(size, sizeof(uint64_t));
+ EXPECT_EQ(value, EVENTFD_TEST_ITERATIONS);
+
+ size = read(fd, &value, sizeof(value));
+ EXPECT_EQ(size, -1);
+ EXPECT_EQ(errno, EAGAIN);
+
+ close(fd);
+}
+
+/*
+ * If EFD_SEMAPHORE was specified and the eventfd counter has a nonzero value,
+ * then a read(2) returns 8 bytes containing the value 1, and the counter's
+ * value is decremented by 1.
+ * If the eventfd counter is zero at the time of the call to read(2), then the
+ * call fails with the error EAGAIN if the file descriptor has been made nonblocking.
+ */
+TEST(eventfd_check_read_with_semaphore)
+{
+ uint64_t value;
+ ssize_t size;
+ int fd;
+ int i;
+
+ fd = sys_eventfd2(0, EFD_SEMAPHORE|EFD_NONBLOCK);
+ ASSERT_GE(fd, 0);
+
+ value = 1;
+ for (i = 0; i < EVENTFD_TEST_ITERATIONS; i++) {
+ size = write(fd, &value, sizeof(value));
+ EXPECT_EQ(size, sizeof(value));
+ }
+
+ for (i = 0; i < EVENTFD_TEST_ITERATIONS; i++) {
+ size = read(fd, &value, sizeof(value));
+ EXPECT_EQ(size, sizeof(value));
+ EXPECT_EQ(value, 1);
+ }
+
+ size = read(fd, &value, sizeof(value));
+ EXPECT_EQ(size, -1);
+ EXPECT_EQ(errno, EAGAIN);
+
+ close(fd);
+}
+
TEST_HARNESS_MAIN
--
2.25.1