On Wed, Mar 06, 2024 at 07:53:57AM -0800, Darrick J. Wong wrote: > On Wed, Mar 06, 2024 at 05:19:33PM +0800, Zorro Lang wrote: > > As the manual of io_uring_queue_init says "io_uring_queue_init(3) > > returns 0 on success and -errno on failure". We should check if the > > return value is -ENOSYS, not the errno. > > /me checks liburing source code and sees that the library returns a > negative error code without touching errno (the semi global error code > variable) at all. That's an unfortunate quirk of the manpage, but this > code here is correct... Yeah, that confuse me too, especially some io_uring functions set errno, some return -errno ... > > > Fixes: d15b1721f284 ("ltp/fsstress: don't fail on io_uring ENOSYS") > > Signed-off-by: Zorro Lang <zlang@xxxxxxxxxx> > > --- > > ltp/fsstress.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/ltp/fsstress.c b/ltp/fsstress.c > > index 63c75767..482395c4 100644 > > --- a/ltp/fsstress.c > > +++ b/ltp/fsstress.c > > @@ -763,8 +763,8 @@ int main(int argc, char **argv) > > #ifdef URING > > have_io_uring = true; > > /* If ENOSYS, just ignore uring, other errors are fatal. */ > > - if (io_uring_queue_init(URING_ENTRIES, &ring, 0)) { > > - if (errno == ENOSYS) { > > + if ((c = io_uring_queue_init(URING_ENTRIES, &ring, 0)) != 0) { > > + if (c == -ENOSYS) { > > have_io_uring = false; > > } else { > > fprintf(stderr, "io_uring_queue_init failed\n"); > > But why not: > > c = io_uring_queue_init(...); > switch (c) { > case 0: > have_io_uring = true; > break; > case -ENOSYS: > have_io_uring = false; > break; > default: > fprintf(stderr, "io_uring_queue_init failed\n"); > break; > } > > Especially since you add another case in the next patch? Sure, that looks more clearly, I'll change this part. Thanks! > > I'll leave the style nits up to you though: > Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx> > > --D > > > --D > > > -- > > 2.43.0 > > > > >