Re: [PATCH] fs/ceph: use release_pages() directly

From: Jeff Layton
Date: Fri Aug 09 2019 - 07:25:04 EST


On Thu, 2019-08-08 at 20:56 -0700, john.hubbard@xxxxxxxxx wrote:
> From: John Hubbard <jhubbard@xxxxxxxxxx>
>
> release_pages() has been available to modules since Oct, 2010,
> when commit 0be8557bcd34 ("fuse: use release_pages()") added
> EXPORT_SYMBOL(release_pages). However, this ceph code was still
> using a workaround.
>
> Remove the workaround, and call release_pages() directly.
>
> Cc: Jeff Layton <jlayton@xxxxxxxxxx>
> Cc: Sage Weil <sage@xxxxxxxxxx>
> Cc: Ilya Dryomov <idryomov@xxxxxxxxx>
> Cc: ceph-devel@xxxxxxxxxxxxxxx
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
> ---
>
> Hi,
>
> I noticed this while I trying to understand mlock.c's use of
> pagevec_release(). So I was looking around for examples, and stumbled
> across this, which seems worth cleaning up.
>
> thanks,
> John Hubbard
> NVIDIA
>
> fs/ceph/addr.c | 19 +------------------
> 1 file changed, 1 insertion(+), 18 deletions(-)
>
> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> index e078cc55b989..22ed45d143be 100644
> --- a/fs/ceph/addr.c
> +++ b/fs/ceph/addr.c
> @@ -679,23 +679,6 @@ static int ceph_writepage(struct page *page, struct writeback_control *wbc)
> return err;
> }
>
> -/*
> - * lame release_pages helper. release_pages() isn't exported to
> - * modules.
> - */
> -static void ceph_release_pages(struct page **pages, int num)
> -{
> - struct pagevec pvec;
> - int i;
> -
> - pagevec_init(&pvec);
> - for (i = 0; i < num; i++) {
> - if (pagevec_add(&pvec, pages[i]) == 0)
> - pagevec_release(&pvec);
> - }
> - pagevec_release(&pvec);
> -}
> -
> /*
> * async writeback completion handler.
> *
> @@ -769,7 +752,7 @@ static void writepages_finish(struct ceph_osd_request *req)
> dout("writepages_finish %p wrote %llu bytes cleaned %d pages\n",
> inode, osd_data->length, rc >= 0 ? num_pages : 0);
>
> - ceph_release_pages(osd_data->pages, num_pages);
> + release_pages(osd_data->pages, num_pages);
> }
>
> ceph_put_wrbuffer_cap_refs(ci, total_pages, snapc);

Thanks John. Running tests on it now, and will probably push to our
testing branch later today. It should make v5.4.

--
Jeff Layton <jlayton@xxxxxxxxxx>