Re: [RFC PATCH v4 4/8] selftests/fuse: factor-out test fixture setup/teardown

[Luis Henriques]

On Thu, Sep 17 2026, Amir Goldstein wrote:

> On Wed, Sep 16, 2026 at 5:55 PM Luis Henriques <luis@xxxxxxxxxx> wrote:
>>
>> In order to reduce new tests setup/teardown code duplication, factor-out
>> these functions from the existing acl_cache test into a new fuse_common.c
>> file that can be reused in other tests.
>>
>> While there, also move some of the FIXTURE members into a fuse_common_ctx
>> structure that can be passed into setup/teardown instead of passing them by
>> reference.
>>
>> Signed-off-by: Luis Henriques <luis@xxxxxxxxxx>
>> ---
>>  .../selftests/filesystems/fuse/Makefile       |  8 +-
>>  .../filesystems/fuse/fuse_acl_cache_test.c    | 73 ++++---------------
>>  .../selftests/filesystems/fuse/fuse_common.c  | 58 +++++++++++++++
>>  .../selftests/filesystems/fuse/fuse_common.h  | 31 ++++++++
>>  4 files changed, 111 insertions(+), 59 deletions(-)
>>  create mode 100644 tools/testing/selftests/filesystems/fuse/fuse_common.c
>>  create mode 100644 tools/testing/selftests/filesystems/fuse/fuse_common.h
>>
>> diff --git a/tools/testing/selftests/filesystems/fuse/Makefile b/tools/testing/selftests/filesystems/fuse/Makefile
>> index a3ee9b3a2f5d..7744f796eb06 100644
>> --- a/tools/testing/selftests/filesystems/fuse/Makefile
>> +++ b/tools/testing/selftests/filesystems/fuse/Makefile
>> @@ -21,8 +21,12 @@ ifeq ($(VAR_LDLIBS),)
>>  VAR_LDLIBS := -lfuse3 -pthread
>>  endif
>>
>> +CFLAGS += $(VAR_CFLAGS)
>> +LDLIBS += $(VAR_LDLIBS)
>> +
>>  $(OUTPUT)/fuse_mnt: CFLAGS += $(VAR_CFLAGS)
>>  $(OUTPUT)/fuse_mnt: LDLIBS += $(VAR_LDLIBS)
>>
>> -$(OUTPUT)/fuse_acl_cache_test: CFLAGS += $(VAR_CFLAGS)
>> -$(OUTPUT)/fuse_acl_cache_test: LDLIBS += $(VAR_LDLIBS)
>> +$(OUTPUT)/fuse_acl_cache_test: fuse_common.c fuse_acl_cache_test.c
>> +
>> +EXTRA_CLEAN := fuse_common.o
>> diff --git a/tools/testing/selftests/filesystems/fuse/fuse_acl_cache_test.c b/tools/testing/selftests/filesystems/fuse/fuse_acl_cache_test.c
>> index 2411a6e285f1..d5a966e7fc15 100644
>> --- a/tools/testing/selftests/filesystems/fuse/fuse_acl_cache_test.c
>> +++ b/tools/testing/selftests/filesystems/fuse/fuse_acl_cache_test.c
>> @@ -33,23 +33,15 @@
>>   */
>>
>>  #define _GNU_SOURCE
>> -#include <errno.h>
>>  #include <fcntl.h>
>>  #include <linux/limits.h>
>> -#include <pthread.h>
>>  #include <stdint.h>
>> -#include <stdio.h>
>> -#include <stdlib.h>
>> -#include <string.h>
>> -#include <sys/stat.h>
>>  #include <sys/xattr.h>
>> -#include <unistd.h>
>> -
>> -#define FUSE_USE_VERSION 31
>> -#include <fuse_lowlevel.h>
>>
>>  #include "kselftest_harness.h"
>>
>> +#include "fuse_common.h"
>> +
>>  /* ---- ACL binary encoding ------------------------------------------------ */
>>  /*
>>   * POSIX ACL v2 xattr format (little-endian):
>> @@ -88,6 +80,7 @@ static const uint8_t acl_b[] = {
>>
>>  struct daemon_state {
>>         pthread_mutex_t lock;
>> +       struct fuse_common_ctx ctx;
>>         const uint8_t  *acl;
>>         size_t          acl_size;
>>         int             getxattr_count;
>> @@ -176,69 +169,35 @@ static const struct fuse_lowlevel_ops fs_ops = {
>>         .getxattr = fs_getxattr,
>>  };
>>
>> -/* ---- Daemon thread ------------------------------------------------------- */
>> -
>> -static void *run_daemon(void *arg)
>> -{
>> -       fuse_session_loop((struct fuse_session *)arg);
>> -       return NULL;
>> -}
>> -
>>  /* ---- kselftest harness --------------------------------------------------- */
>>
>>  FIXTURE(acl_cache) {
>> -       struct fuse_session *se;
>> -       char                 mountpoint[PATH_MAX];
>> -       char                 file_path[PATH_MAX];
>> -       pthread_t            thread;
>> +       char file_path[PATH_MAX];
>>  };
>>
>
> Hi Luis,
>
> Thanks for the followup cleanup.
> Question: why did you move struct fuse_common_ctx out of the test
> fixture and into the global state?
> It not terribly wrong but seems unnecessary and inconsistent -
> fs_setup/teardown are in FIXTURE_SETUP/TEARDOWN
> so it is more consistent that fuse_common_ctx stays embedded in the
> fixure object, unless you have a reason to counter.

Well, I do not have a good reason so I'll move that struct into the
FIXTURE :-)

You're right, it probably makes more sense to keep these separate from the
test state.  I'll fix this test (and the other ones).

Cheers,
-- 
Luís


> With that fix, feel free to add
>
> Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
>
> Thanks,
> Amir.
>
>>  FIXTURE_SETUP(acl_cache)
>>  {
>> -       char *fuse_argv[] = { "fuse_acl_cache_test", NULL };
>> -       struct fuse_args args = FUSE_ARGS_INIT(1, fuse_argv);
>> +       char err[MAX_ERR_MSG];
>>
>> -       g_ds.acl            = acl_a;
>> -       g_ds.acl_size       = sizeof(acl_a);
>> +       pthread_mutex_lock(&g_ds.lock);
>> +       g_ds.acl = acl_a;
>> +       g_ds.acl_size = sizeof(acl_a);
>>         g_ds.getxattr_count = 0;
>>
>> -       strcpy(self->mountpoint, "/tmp/acl_cache_test_XXXXXX");
>> -       if (!mkdtemp(self->mountpoint))
>> -               SKIP(return, "mkdtemp: %s", strerror(errno));
>> +       if (fs_setup(&fs_ops, &g_ds.ctx, err))
>> +               SKIP(goto out, err);
>>
>>         snprintf(self->file_path, sizeof(self->file_path),
>> -                "%s/" FILE_NAME, self->mountpoint);
>> -
>> -       self->se = fuse_session_new(&args, &fs_ops, sizeof(fs_ops), NULL);
>> -       if (!self->se) {
>> -               rmdir(self->mountpoint);
>> -               SKIP(return, "fuse_session_new failed");
>> -       }
>> -
>> -       if (fuse_session_mount(self->se, self->mountpoint)) {
>> -               fuse_session_destroy(self->se);
>> -               rmdir(self->mountpoint);
>> -               SKIP(return, "fuse_session_mount failed "
>> -                            "(missing fusermount3 or insufficient privileges)");
>> -       }
>> -
>> -       if (pthread_create(&self->thread, NULL, run_daemon, self->se)) {
>> -               fuse_session_unmount(self->se);
>> -               fuse_session_destroy(self->se);
>> -               rmdir(self->mountpoint);
>> -               SKIP(return, "pthread_create: %s", strerror(errno));
>> -       }
>> -
>> -       fuse_opt_free_args(&args);
>> +                "%s/" FILE_NAME, g_ds.ctx.mountpoint);
>> +out:
>> +       pthread_mutex_unlock(&g_ds.lock);
>>  }
>>
>>  FIXTURE_TEARDOWN(acl_cache)
>>  {
>> -       fuse_session_exit(self->se);
>> -       fuse_session_unmount(self->se);
>> -       pthread_join(self->thread, NULL);
>> -       fuse_session_destroy(self->se);
>> -       rmdir(self->mountpoint);
>> +       pthread_mutex_lock(&g_ds.lock);
>> +       fs_teardown(&g_ds.ctx);
>> +       pthread_mutex_unlock(&g_ds.lock);
>>  }
>>
>>  static int do_force_statx(const char *path)
>> diff --git a/tools/testing/selftests/filesystems/fuse/fuse_common.c b/tools/testing/selftests/filesystems/fuse/fuse_common.c
>> new file mode 100644
>> index 000000000000..d1d3dfd2ea67
>> --- /dev/null
>> +++ b/tools/testing/selftests/filesystems/fuse/fuse_common.c
>> @@ -0,0 +1,58 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +
>> +#include "fuse_common.h"
>> +
>> +static void *run_daemon(void *arg)
>> +{
>> +       fuse_session_loop((struct fuse_session *)arg);
>> +       return NULL;
>> +}
>> +
>> +int fs_setup(const struct fuse_lowlevel_ops *fs_ops,
>> +            struct fuse_common_ctx *ctx, char *err)
>> +{
>> +       char *fuse_argv[] = { "fuse_test", NULL };
>> +       struct fuse_args args = FUSE_ARGS_INIT(1, fuse_argv);
>> +
>> +       strcpy(ctx->mountpoint, MOUNTPOINT_TEMPLATE);
>> +       if (!mkdtemp(ctx->mountpoint)) {
>> +               snprintf(err, MAX_ERR_MSG, "mkdtemp: %s", strerror(errno));
>> +               return -1;
>> +       }
>> +
>> +       ctx->se = fuse_session_new(&args, fs_ops, sizeof(*fs_ops), NULL);
>> +       if (!ctx->se) {
>> +               rmdir(ctx->mountpoint);
>> +               snprintf(err, MAX_ERR_MSG, "fuse_session_new failed");
>> +               return -1;
>> +       }
>> +
>> +       if (fuse_session_mount(ctx->se, ctx->mountpoint)) {
>> +               fuse_session_destroy(ctx->se);
>> +               rmdir(ctx->mountpoint);
>> +               snprintf(err, MAX_ERR_MSG, "fuse_session_mount failed "
>> +                       "(missing fusermount3 or insufficient privileges)");
>> +               return -1;
>> +       }
>> +
>> +       if (pthread_create(&ctx->thread, NULL, run_daemon, ctx->se)) {
>> +               fuse_session_unmount(ctx->se);
>> +               fuse_session_destroy(ctx->se);
>> +               rmdir(ctx->mountpoint);
>> +               snprintf(err, MAX_ERR_MSG, "pthread_create: %s", strerror(errno));
>> +               return -1;
>> +       }
>> +
>> +       fuse_opt_free_args(&args);
>> +
>> +       return 0;
>> +}
>> +
>> +void fs_teardown(struct fuse_common_ctx *ctx)
>> +{
>> +       fuse_session_exit(ctx->se);
>> +       fuse_session_unmount(ctx->se);
>> +       pthread_join(ctx->thread, NULL);
>> +       fuse_session_destroy(ctx->se);
>> +       rmdir(ctx->mountpoint);
>> +}
>> diff --git a/tools/testing/selftests/filesystems/fuse/fuse_common.h b/tools/testing/selftests/filesystems/fuse/fuse_common.h
>> new file mode 100644
>> index 000000000000..e3dd85daa4b0
>> --- /dev/null
>> +++ b/tools/testing/selftests/filesystems/fuse/fuse_common.h
>> @@ -0,0 +1,31 @@
>> +#ifndef __SELFTEST_FUSE_COMMON_H__
>> +#define __SELFTEST_FUSE_COMMON_H__
>> +
>> +#define _GNU_SOURCE
>> +#include <errno.h>
>> +#include <pthread.h>
>> +#include <stdio.h>
>> +#include <stdlib.h>
>> +#include <string.h>
>> +#include <unistd.h>
>> +#include <limits.h>
>> +
>> +#define FUSE_USE_VERSION 31
>> +#include <fuse_lowlevel.h>
>> +
>> +#define MAX_ERR_MSG 256
>> +
>> +#define MOUNTPOINT_TEMPLATE "/tmp/fuse_test_XXXXXX"
>> +#define MOUNTPOINT_SZ 64
>> +
>> +struct fuse_common_ctx {
>> +       struct fuse_session *se;
>> +       char mountpoint[MOUNTPOINT_SZ];
>> +       pthread_t thread;
>> +};
>> +
>> +int fs_setup(const struct fuse_lowlevel_ops *fs_ops,
>> +            struct fuse_common_ctx *ctx, char *err);
>> +void fs_teardown(struct fuse_common_ctx *ctx);
>> +
>> +#endif /* __SELFTEST_FUSE_COMMON_H__ */