On Mon, Jan 22, 2024 at 4:02 PM Jeff Layton <jlayton@xxxxxxxxxx> wrote: > > On Thu, 2024-01-18 at 18:50 +0800, xiubli@xxxxxxxxxx wrote: > > From: Xiubo Li <xiubli@xxxxxxxxxx> > > > > The messages from ceph maybe split into multiple socket packages > > and we just need to wait for all the data to be availiable on the > > sokcet. > > > > This will add 'sr_total_resid' to record the total length for all > > data items for sparse-read message and 'sr_resid_elen' to record > > the current extent total length. > > > > URL: https://tracker.ceph.com/issues/63586 > > Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx> > > --- > > include/linux/ceph/messenger.h | 1 + > > net/ceph/messenger_v1.c | 32 +++++++++++++++++++++----------- > > 2 files changed, 22 insertions(+), 11 deletions(-) > > > > diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h > > index 2eaaabbe98cb..ca6f82abed62 100644 > > --- a/include/linux/ceph/messenger.h > > +++ b/include/linux/ceph/messenger.h > > @@ -231,6 +231,7 @@ struct ceph_msg_data { > > > > struct ceph_msg_data_cursor { > > size_t total_resid; /* across all data items */ > > + size_t sr_total_resid; /* across all data items for sparse-read */ > > > > struct ceph_msg_data *data; /* current data item */ > > size_t resid; /* bytes not yet consumed */ > > diff --git a/net/ceph/messenger_v1.c b/net/ceph/messenger_v1.c > > index 4cb60bacf5f5..2733da891688 100644 > > --- a/net/ceph/messenger_v1.c > > +++ b/net/ceph/messenger_v1.c > > @@ -160,7 +160,9 @@ static size_t sizeof_footer(struct ceph_connection *con) > > static void prepare_message_data(struct ceph_msg *msg, u32 data_len) > > { > > /* Initialize data cursor if it's not a sparse read */ > > - if (!msg->sparse_read) > > + if (msg->sparse_read) > > + msg->cursor.sr_total_resid = data_len; > > + else > > ceph_msg_data_cursor_init(&msg->cursor, msg, data_len); > > } > > > > > > Sorry, disregard my last email. > > I went and looked at the patch in the tree, and I better understand what > you're trying to do. We already have a value that gets set to data_len > called total_resid, but that is a nonsense value in a sparse read, > because we can advance farther through the receive buffer than the > amount of data in the socket. Hi Jeff, I see that total_resid is set to sparse_data_requested(), which is effectively the size of the receive buffer, not data_len. (This is ignoring the seemingly unnecessary complication of trying to support normal reads mixed with sparse reads in the same message, which I'm pretty sure doesn't work anyway.) With that, total_resid should represent the amount that needs to be filled in (advanced through) in the receive buffer. When total_resid reaches 0, wouldn't that mean that the amount of data in the socket is also 0? If not, where would the remaining data in the socket go? Thanks, Ilya
