Commit 87beb669 authored by Wen Yang's avatar Wen Yang Committed by Andrew Morton
Browse files

selftests: introduce additional eventfd test coverage 

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

Link: https://lkml.kernel.org/r/20240527000200.5615-1-wen.yang@linux.dev


Signed-off-by: default avatarWen Yang <wen.yang@linux.dev>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Andrei Vagin <avagin@google.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Tim Bird <tim.bird@sony.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 51d82165

tools/testing/selftests/filesystems/eventfd/eventfd_test.c

+131 −5
Original line number Diff line number Diff line
@@ -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