selftests: add eventfd selftests

This adds the promised selftest for eventfd.  It will verify the flags of
eventfd2, including EFD_CLOEXEC, EFD_NONBLOCK and EFD_SEMAPHORE.

Link: https://lkml.kernel.org/r/tencent_3C9A298878D22B5D8F79DC2FEE99BB4A8F05@qq.com
Signed-off-by: Wen Yang <wenyang.linux@foxmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Pengfei Xu <pengfei.xu@intel.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Andrei Vagin <avagin@google.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/tools/testing/selftests/filesystems/eventfd/.gitignore b/tools/testing/selftests/filesystems/eventfd/.gitignore
new file mode 100644 (file)
index 0000000..483faf5
--- /dev/null
+++ b/tools/testing/selftests/filesystems/eventfd/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+eventfd_test

diff --git a/tools/testing/selftests/filesystems/eventfd/Makefile b/tools/testing/selftests/filesystems/eventfd/Makefile
new file mode 100644 (file)
index 0000000..0a8e391
--- /dev/null
+++ b/tools/testing/selftests/filesystems/eventfd/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+CFLAGS += $(KHDR_INCLUDES)
+LDLIBS += -lpthread
+TEST_GEN_PROGS := eventfd_test
+
+include ../../lib.mk

diff --git a/tools/testing/selftests/filesystems/eventfd/eventfd_test.c b/tools/testing/selftests/filesystems/eventfd/eventfd_test.c
new file mode 100644 (file)
index 0000000..f142a13
--- /dev/null
+++ b/tools/testing/selftests/filesystems/eventfd/eventfd_test.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <asm/unistd.h>
+#include <linux/time_types.h>
+#include <unistd.h>
+#include <assert.h>
+#include <signal.h>
+#include <pthread.h>
+#include <sys/epoll.h>
+#include <sys/eventfd.h>
+#include "../../kselftest_harness.h"
+
+struct error {
+       int  code;
+       char msg[512];
+};
+
+static int error_set(struct error *err, int code, const char *fmt, ...)
+{
+       va_list args;
+       int r;
+
+       if (code == 0 || !err || err->code != 0)
+               return code;
+
+       err->code = code;
+       va_start(args, fmt);
+       r = vsnprintf(err->msg, sizeof(err->msg), fmt, args);
+       assert((size_t)r < sizeof(err->msg));
+       va_end(args);
+
+       return code;
+}
+
+static inline int sys_eventfd2(unsigned int count, int flags)
+{
+       return syscall(__NR_eventfd2, count, flags);
+}
+
+TEST(eventfd01)
+{
+       int fd, flags;
+
+       fd = sys_eventfd2(0, 0);
+       ASSERT_GE(fd, 0);
+
+       flags = fcntl(fd, F_GETFL);
+       // since the kernel automatically added O_RDWR.
+       EXPECT_EQ(flags, O_RDWR);
+
+       close(fd);
+}
+
+TEST(eventfd02)
+{
+       int fd, flags;
+
+       fd = sys_eventfd2(0, EFD_CLOEXEC);
+       ASSERT_GE(fd, 0);
+
+       flags = fcntl(fd, F_GETFD);
+       ASSERT_GT(flags, -1);
+       EXPECT_EQ(flags, FD_CLOEXEC);
+
+       close(fd);
+}
+
+TEST(eventfd03)
+{
+       int fd, flags;
+
+       fd = sys_eventfd2(0, EFD_NONBLOCK);
+       ASSERT_GE(fd, 0);
+
+       flags = fcntl(fd, F_GETFL);
+       ASSERT_GT(flags, -1);
+       EXPECT_EQ(flags & EFD_NONBLOCK, EFD_NONBLOCK);
+       EXPECT_EQ(flags & O_RDWR, O_RDWR);
+
+       close(fd);
+}
+
+TEST(eventfd04)
+{
+       int fd, flags;
+
+       fd = sys_eventfd2(0, EFD_CLOEXEC|EFD_NONBLOCK);
+       ASSERT_GE(fd, 0);
+
+       flags = fcntl(fd, F_GETFL);
+       ASSERT_GT(flags, -1);
+       EXPECT_EQ(flags & EFD_NONBLOCK, EFD_NONBLOCK);
+       EXPECT_EQ(flags & O_RDWR, O_RDWR);
+
+       flags = fcntl(fd, F_GETFD);
+       ASSERT_GT(flags, -1);
+       EXPECT_EQ(flags, FD_CLOEXEC);
+
+       close(fd);
+}
+
+static inline void trim_newline(char *str)
+{
+       char *pos = strrchr(str, '\n');
+
+       if (pos)
+               *pos = '\0';
+}
+
+static int verify_fdinfo(int fd, struct error *err, const char *prefix,
+               size_t prefix_len, const char *expect, ...)
+{
+       char buffer[512] = {0, };
+       char path[512] = {0, };
+       va_list args;
+       FILE *f;
+       char *line = NULL;
+       size_t n = 0;
+       int found = 0;
+       int r;
+
+       va_start(args, expect);
+       r = vsnprintf(buffer, sizeof(buffer), expect, args);
+       assert((size_t)r < sizeof(buffer));
+       va_end(args);
+
+       snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
+       f = fopen(path, "re");
+       if (!f)
+               return error_set(err, -1, "fdinfo open failed for %d", fd);
+
+       while (getline(&line, &n, f) != -1) {
+               char *val;
+
+               if (strncmp(line, prefix, prefix_len))
+                       continue;
+
+               found = 1;
+
+               val = line + prefix_len;
+               r = strcmp(val, buffer);
+               if (r != 0) {
+                       trim_newline(line);
+                       trim_newline(buffer);
+                       error_set(err, -1, "%s '%s' != '%s'",
+                                 prefix, val, buffer);
+               }
+               break;
+       }
+
+       free(line);
+       fclose(f);
+
+       if (found == 0)
+               return error_set(err, -1, "%s not found for fd %d",
+                                prefix, fd);
+
+       return 0;
+}
+
+TEST(eventfd05)
+{
+       struct error err = {0};
+       int fd, ret;
+
+       fd = sys_eventfd2(0, EFD_SEMAPHORE);
+       ASSERT_GE(fd, 0);
+
+       ret = fcntl(fd, F_GETFL);
+       ASSERT_GT(ret, -1);
+       EXPECT_EQ(ret & O_RDWR, O_RDWR);
+
+       // The semaphore could only be obtained from fdinfo.
+       ret = verify_fdinfo(fd, &err, "eventfd-semaphore: ", 19, "1\n");
+       if (ret != 0)
+               ksft_print_msg("eventfd-semaphore check failed, msg: %s\n",
+                               err.msg);
+       EXPECT_EQ(ret, 0);
+
+       close(fd);
+}
+
+TEST_HARNESS_MAIN