Re: [RFC PATCH 1/3] libceph: add non-blocking version of ceph_osdc_copy_from()

Ilya Dryomov
2020-01-27T17:46:57Z

On Mon, Jan 27, 2020 at 5:43 PM Luis Henriques <lhenriques@suse.com> wrote:
>
> A non-blocking version of ceph_osdc_copy_from will allow for callers to
> send 'copy-from' requests in bulk and wait for all of them to complete in
> the end.
>
> Signed-off-by: Luis Henriques <lhenriques@suse.com>
> ---
> include/linux/ceph/osd_client.h | 12 ++++++++
> net/ceph/osd_client.c | 54 +++++++++++++++++++++++++--------
> 2 files changed, 53 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h
> index 5a62dbd3f4c2..7916a178d137 100644
> --- a/include/linux/ceph/osd_client.h
> +++ b/include/linux/ceph/osd_client.h
> @@ -537,6 +537,18 @@ int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
> u32 truncate_seq, u64 truncate_size,
> u8 copy_from_flags);
>
> +struct ceph_osd_request *ceph_osdc_copy_from_nowait(
> + struct ceph_osd_client *osdc,
> + u64 src_snapid, u64 src_version,
> + struct ceph_object_id *src_oid,
> + struct ceph_object_locator *src_oloc,
> + u32 src_fadvise_flags,
> + struct ceph_object_id *dst_oid,
> + struct ceph_object_locator *dst_oloc,
> + u32 dst_fadvise_flags,
> + u32 truncate_seq, u64 truncate_size,
> + u8 copy_from_flags);
> +
> /* watch/notify */
> struct ceph_osd_linger_request *
> ceph_osdc_watch(struct ceph_osd_client *osdc,
> diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
> index b68b376d8c2f..7f984532f37c 100644
> --- a/net/ceph/osd_client.c
> +++ b/net/ceph/osd_client.c
> @@ -5346,23 +5346,24 @@ static int osd_req_op_copy_from_init(struct ceph_osd_request *req,
> return 0;
> }
>
> -int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
> - u64 src_snapid, u64 src_version,
> - struct ceph_object_id *src_oid,
> - struct ceph_object_locator *src_oloc,
> - u32 src_fadvise_flags,
> - struct ceph_object_id *dst_oid,
> - struct ceph_object_locator *dst_oloc,
> - u32 dst_fadvise_flags,
> - u32 truncate_seq, u64 truncate_size,
> - u8 copy_from_flags)
> +struct ceph_osd_request *ceph_osdc_copy_from_nowait(
> + struct ceph_osd_client *osdc,
> + u64 src_snapid, u64 src_version,
> + struct ceph_object_id *src_oid,
> + struct ceph_object_locator *src_oloc,
> + u32 src_fadvise_flags,
> + struct ceph_object_id *dst_oid,
> + struct ceph_object_locator *dst_oloc,
> + u32 dst_fadvise_flags,
> + u32 truncate_seq, u64 truncate_size,
> + u8 copy_from_flags)
> {
> struct ceph_osd_request *req;
> int ret;
>
> req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
> if (!req)
> - return -ENOMEM;
> + return ERR_PTR(-ENOMEM);
>
> req->r_flags = CEPH_OSD_FLAG_WRITE;
>
> @@ -5381,11 +5382,38 @@ int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
> goto out;
>
> ceph_osdc_start_request(osdc, req, false);
> - ret = ceph_osdc_wait_request(osdc, req);
> + return req;
>
> out:
> ceph_osdc_put_request(req);
> - return ret;
> + return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL(ceph_osdc_copy_from_nowait);
> +
> +int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
> + u64 src_snapid, u64 src_version,
> + struct ceph_object_id *src_oid,
> + struct ceph_object_locator *src_oloc,
> + u32 src_fadvise_flags,
> + struct ceph_object_id *dst_oid,
> + struct ceph_object_locator *dst_oloc,
> + u32 dst_fadvise_flags,
> + u32 truncate_seq, u64 truncate_size,
> + u8 copy_from_flags)
> +{
> + struct ceph_osd_request *req;
> +
> + req = ceph_osdc_copy_from_nowait(osdc,
> + src_snapid, src_version,
> + src_oid, src_oloc,
> + src_fadvise_flags,
> + dst_oid, dst_oloc,
> + dst_fadvise_flags,
> + truncate_seq, truncate_size,
> + copy_from_flags);
> + if (IS_ERR(req))
> + return PTR_ERR(req);
> + return ceph_osdc_wait_request(osdc, req);

I don't think we need a blocking version. Change ceph_osdc_copy_from()
and keep the name -- no need for async or nowait suffixes.

Thanks,

Ilya