| Message ID | 20170225174323.20289-2-jlayton@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, Feb 25, 2017 at 6:43 PM, Jeff Layton <jlayton@redhat.com> wrote: > Usually, when the osd map is flagged as full or the pool is at quota, > write requests just hang. This is not what we want for cephfs, where > it would be better to simply report -ENOSPC back to userland instead > of stalling. > > If the caller knows that it will want an immediate error return instead > of blocking on a full or at-quota error condition then allow it to set a > flag to request that behavior. > > Set that flag in ceph_osdc_new_request (since ceph.ko is the only caller), > and on any other write request from ceph.ko. > > A later patch will deal with requests that were submitted before the new > map showing the full condition came in. > > Signed-off-by: Jeff Layton <jlayton@redhat.com> > --- > fs/ceph/addr.c | 1 + > fs/ceph/file.c | 1 + > include/linux/ceph/osd_client.h | 1 + > net/ceph/osd_client.c | 7 +++++++ > 4 files changed, 10 insertions(+) > > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c > index 6ecb920602ed..4b9da6ee5c7f 100644 > --- a/fs/ceph/addr.c > +++ b/fs/ceph/addr.c > @@ -1889,6 +1889,7 @@ static int __ceph_pool_perm_get(struct ceph_inode_info *ci, > err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false); > > wr_req->r_mtime = ci->vfs_inode.i_mtime; > + wr_req->r_abort_on_full = true; > err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false); > > if (!err) > diff --git a/fs/ceph/file.c b/fs/ceph/file.c > index 5a7134ef13d3..9dad32d0ed0b 100644 > --- a/fs/ceph/file.c > +++ b/fs/ceph/file.c > @@ -712,6 +712,7 @@ static void ceph_aio_retry_work(struct work_struct *work) > req->r_callback = ceph_aio_complete_req; > req->r_inode = inode; > req->r_priv = aio_req; > + req->r_abort_on_full = true; > > ret = ceph_osdc_start_request(req->r_osdc, req, false); > out: > diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h > index f2ce9cd5ede6..55dcff2455e0 100644 > --- a/include/linux/ceph/osd_client.h > +++ b/include/linux/ceph/osd_client.h > @@ -169,6 +169,7 @@ struct ceph_osd_request { > unsigned int r_num_ops; > > int r_result; > + bool r_abort_on_full; /* return ENOSPC when full */ Move this under "set by submitter", after r_linger? > > struct ceph_osd_client *r_osdc; > struct kref r_kref; > diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c > index 5c0938ddddf6..8fc0ccc7126f 100644 > --- a/net/ceph/osd_client.c > +++ b/net/ceph/osd_client.c > @@ -49,6 +49,7 @@ static void link_linger(struct ceph_osd *osd, > struct ceph_osd_linger_request *lreq); > static void unlink_linger(struct ceph_osd *osd, > struct ceph_osd_linger_request *lreq); > +static void complete_request(struct ceph_osd_request *req, int err); Move this closer to __submit_request(), before send_map_check() forward declaration? > > #if 1 > static inline bool rwsem_is_wrlocked(struct rw_semaphore *sem) > @@ -961,6 +962,7 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc, > truncate_size, truncate_seq); > } > > + req->r_abort_on_full = true; > req->r_flags = flags; > req->r_base_oloc.pool = layout->pool_id; > req->r_base_oloc.pool_ns = ceph_try_get_string(layout->pool_ns); > @@ -1635,6 +1637,7 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) > enum calc_target_result ct_res; > bool need_send = false; bool need_abort here instead of ret? This is a filesystem specific hack, so it's always going to be ENOSPC. > bool promoted = false; > + int ret = 0; > > WARN_ON(req->r_tid); > dout("%s req %p wrlocked %d\n", __func__, req, wrlocked); > @@ -1669,6 +1672,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) > pr_warn_ratelimited("FULL or reached pool quota\n"); > req->r_t.paused = true; > maybe_request_map(osdc); > + if (req->r_abort_on_full) > + ret = -ENOSPC; > } else if (!osd_homeless(osd)) { > need_send = true; > } else { > @@ -1685,6 +1690,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) > link_request(osd, req); > if (need_send) > send_request(req); > + else if (ret) > + complete_request(req, ret); I think this is the first complete_request() on the submit thread, so I'm a little worried about possible deadlocks and/or other weirdness. Did you look through all start/handle_reply sites in the filesystem? Thanks, Ilya -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2017-03-28 at 16:22 +0200, Ilya Dryomov wrote: > On Sat, Feb 25, 2017 at 6:43 PM, Jeff Layton <jlayton@redhat.com> wrote: > > Usually, when the osd map is flagged as full or the pool is at quota, > > write requests just hang. This is not what we want for cephfs, where > > it would be better to simply report -ENOSPC back to userland instead > > of stalling. > > > > If the caller knows that it will want an immediate error return instead > > of blocking on a full or at-quota error condition then allow it to set a > > flag to request that behavior. > > > > Set that flag in ceph_osdc_new_request (since ceph.ko is the only caller), > > and on any other write request from ceph.ko. > > > > A later patch will deal with requests that were submitted before the new > > map showing the full condition came in. > > > > Signed-off-by: Jeff Layton <jlayton@redhat.com> > > --- > > fs/ceph/addr.c | 1 + > > fs/ceph/file.c | 1 + > > include/linux/ceph/osd_client.h | 1 + > > net/ceph/osd_client.c | 7 +++++++ > > 4 files changed, 10 insertions(+) > > > > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c > > index 6ecb920602ed..4b9da6ee5c7f 100644 > > --- a/fs/ceph/addr.c > > +++ b/fs/ceph/addr.c > > @@ -1889,6 +1889,7 @@ static int __ceph_pool_perm_get(struct ceph_inode_info *ci, > > err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false); > > > > wr_req->r_mtime = ci->vfs_inode.i_mtime; > > + wr_req->r_abort_on_full = true; > > err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false); > > > > if (!err) > > diff --git a/fs/ceph/file.c b/fs/ceph/file.c > > index 5a7134ef13d3..9dad32d0ed0b 100644 > > --- a/fs/ceph/file.c > > +++ b/fs/ceph/file.c > > @@ -712,6 +712,7 @@ static void ceph_aio_retry_work(struct work_struct *work) > > req->r_callback = ceph_aio_complete_req; > > req->r_inode = inode; > > req->r_priv = aio_req; > > + req->r_abort_on_full = true; > > > > ret = ceph_osdc_start_request(req->r_osdc, req, false); > > out: > > diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h > > index f2ce9cd5ede6..55dcff2455e0 100644 > > --- a/include/linux/ceph/osd_client.h > > +++ b/include/linux/ceph/osd_client.h > > @@ -169,6 +169,7 @@ struct ceph_osd_request { > > unsigned int r_num_ops; > > > > int r_result; > > + bool r_abort_on_full; /* return ENOSPC when full */ > > Move this under "set by submitter", after r_linger? > > > > > struct ceph_osd_client *r_osdc; > > struct kref r_kref; > > diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c > > index 5c0938ddddf6..8fc0ccc7126f 100644 > > --- a/net/ceph/osd_client.c > > +++ b/net/ceph/osd_client.c > > @@ -49,6 +49,7 @@ static void link_linger(struct ceph_osd *osd, > > struct ceph_osd_linger_request *lreq); > > static void unlink_linger(struct ceph_osd *osd, > > struct ceph_osd_linger_request *lreq); > > +static void complete_request(struct ceph_osd_request *req, int err); > > Move this closer to __submit_request(), before send_map_check() forward > declaration? > > > > > #if 1 > > static inline bool rwsem_is_wrlocked(struct rw_semaphore *sem) > > @@ -961,6 +962,7 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc, > > truncate_size, truncate_seq); > > } > > > > + req->r_abort_on_full = true; > > req->r_flags = flags; > > req->r_base_oloc.pool = layout->pool_id; > > req->r_base_oloc.pool_ns = ceph_try_get_string(layout->pool_ns); > > @@ -1635,6 +1637,7 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) > > enum calc_target_result ct_res; > > bool need_send = false; > > bool need_abort here instead of ret? This is a filesystem specific > hack, so it's always going to be ENOSPC. > Fixing all of the above for the next iteration. > > bool promoted = false; > > + int ret = 0; > > > > WARN_ON(req->r_tid); > > dout("%s req %p wrlocked %d\n", __func__, req, wrlocked); > > @@ -1669,6 +1672,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) > > pr_warn_ratelimited("FULL or reached pool quota\n"); > > req->r_t.paused = true; > > maybe_request_map(osdc); > > + if (req->r_abort_on_full) > > + ret = -ENOSPC; > > } else if (!osd_homeless(osd)) { > > need_send = true; > > } else { > > @@ -1685,6 +1690,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) > > link_request(osd, req); > > if (need_send) > > send_request(req); > > + else if (ret) > > + complete_request(req, ret); > > I think this is the first complete_request() on the submit thread, so > I'm a little worried about possible deadlocks and/or other weirdness. > Did you look through all start/handle_reply sites in the filesystem? > I did. That's not to say I didn't miss anything, but as far as I can tell, we expect to call complete_request with the osd locked, and it is at this point in the __submit_request codepath. Thanks for the comments so far!
On Tue, Mar 28, 2017 at 10:12 PM, Jeff Layton <jlayton@redhat.com> wrote: > On Tue, 2017-03-28 at 16:22 +0200, Ilya Dryomov wrote: >> On Sat, Feb 25, 2017 at 6:43 PM, Jeff Layton <jlayton@redhat.com> wrote: >> > Usually, when the osd map is flagged as full or the pool is at quota, >> > write requests just hang. This is not what we want for cephfs, where >> > it would be better to simply report -ENOSPC back to userland instead >> > of stalling. >> > >> > If the caller knows that it will want an immediate error return instead >> > of blocking on a full or at-quota error condition then allow it to set a >> > flag to request that behavior. >> > >> > Set that flag in ceph_osdc_new_request (since ceph.ko is the only caller), >> > and on any other write request from ceph.ko. >> > >> > A later patch will deal with requests that were submitted before the new >> > map showing the full condition came in. >> > >> > Signed-off-by: Jeff Layton <jlayton@redhat.com> >> > --- >> > fs/ceph/addr.c | 1 + >> > fs/ceph/file.c | 1 + >> > include/linux/ceph/osd_client.h | 1 + >> > net/ceph/osd_client.c | 7 +++++++ >> > 4 files changed, 10 insertions(+) >> > >> > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c >> > index 6ecb920602ed..4b9da6ee5c7f 100644 >> > --- a/fs/ceph/addr.c >> > +++ b/fs/ceph/addr.c >> > @@ -1889,6 +1889,7 @@ static int __ceph_pool_perm_get(struct ceph_inode_info *ci, >> > err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false); >> > >> > wr_req->r_mtime = ci->vfs_inode.i_mtime; >> > + wr_req->r_abort_on_full = true; >> > err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false); >> > >> > if (!err) >> > diff --git a/fs/ceph/file.c b/fs/ceph/file.c >> > index 5a7134ef13d3..9dad32d0ed0b 100644 >> > --- a/fs/ceph/file.c >> > +++ b/fs/ceph/file.c >> > @@ -712,6 +712,7 @@ static void ceph_aio_retry_work(struct work_struct *work) >> > req->r_callback = ceph_aio_complete_req; >> > req->r_inode = inode; >> > req->r_priv = aio_req; >> > + req->r_abort_on_full = true; >> > >> > ret = ceph_osdc_start_request(req->r_osdc, req, false); >> > out: >> > diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h >> > index f2ce9cd5ede6..55dcff2455e0 100644 >> > --- a/include/linux/ceph/osd_client.h >> > +++ b/include/linux/ceph/osd_client.h >> > @@ -169,6 +169,7 @@ struct ceph_osd_request { >> > unsigned int r_num_ops; >> > >> > int r_result; >> > + bool r_abort_on_full; /* return ENOSPC when full */ >> >> Move this under "set by submitter", after r_linger? >> >> > >> > struct ceph_osd_client *r_osdc; >> > struct kref r_kref; >> > diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c >> > index 5c0938ddddf6..8fc0ccc7126f 100644 >> > --- a/net/ceph/osd_client.c >> > +++ b/net/ceph/osd_client.c >> > @@ -49,6 +49,7 @@ static void link_linger(struct ceph_osd *osd, >> > struct ceph_osd_linger_request *lreq); >> > static void unlink_linger(struct ceph_osd *osd, >> > struct ceph_osd_linger_request *lreq); >> > +static void complete_request(struct ceph_osd_request *req, int err); >> >> Move this closer to __submit_request(), before send_map_check() forward >> declaration? >> >> > >> > #if 1 >> > static inline bool rwsem_is_wrlocked(struct rw_semaphore *sem) >> > @@ -961,6 +962,7 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc, >> > truncate_size, truncate_seq); >> > } >> > >> > + req->r_abort_on_full = true; >> > req->r_flags = flags; >> > req->r_base_oloc.pool = layout->pool_id; >> > req->r_base_oloc.pool_ns = ceph_try_get_string(layout->pool_ns); >> > @@ -1635,6 +1637,7 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) >> > enum calc_target_result ct_res; >> > bool need_send = false; >> >> bool need_abort here instead of ret? This is a filesystem specific >> hack, so it's always going to be ENOSPC. >> > > Fixing all of the above for the next iteration. > >> > bool promoted = false; >> > + int ret = 0; >> > >> > WARN_ON(req->r_tid); >> > dout("%s req %p wrlocked %d\n", __func__, req, wrlocked); >> > @@ -1669,6 +1672,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) >> > pr_warn_ratelimited("FULL or reached pool quota\n"); >> > req->r_t.paused = true; >> > maybe_request_map(osdc); >> > + if (req->r_abort_on_full) >> > + ret = -ENOSPC; >> > } else if (!osd_homeless(osd)) { >> > need_send = true; >> > } else { >> > @@ -1685,6 +1690,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) >> > link_request(osd, req); >> > if (need_send) >> > send_request(req); >> > + else if (ret) >> > + complete_request(req, ret); >> >> I think this is the first complete_request() on the submit thread, so >> I'm a little worried about possible deadlocks and/or other weirdness. >> Did you look through all start/handle_reply sites in the filesystem? >> > > I did. That's not to say I didn't miss anything, but as far as I can > tell, we expect to call complete_request with the osd locked, and it is > at this point in the __submit_request codepath. It's not the osd->lock, more the surrounding filesystem locks/context. I looked briefly earlier and didn't notice anything alarming either. If it blows up, blame it on teuthology test coverage ;) Speaking of teuthology, we need to look into enabling qa/tasks/cephfs/test_full.py tests for the kernel client once these patches are finalized. Thanks, Ilya -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 6ecb920602ed..4b9da6ee5c7f 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -1889,6 +1889,7 @@ static int __ceph_pool_perm_get(struct ceph_inode_info *ci, err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false); wr_req->r_mtime = ci->vfs_inode.i_mtime; + wr_req->r_abort_on_full = true; err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false); if (!err) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 5a7134ef13d3..9dad32d0ed0b 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -712,6 +712,7 @@ static void ceph_aio_retry_work(struct work_struct *work) req->r_callback = ceph_aio_complete_req; req->r_inode = inode; req->r_priv = aio_req; + req->r_abort_on_full = true; ret = ceph_osdc_start_request(req->r_osdc, req, false); out: diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h index f2ce9cd5ede6..55dcff2455e0 100644 --- a/include/linux/ceph/osd_client.h +++ b/include/linux/ceph/osd_client.h @@ -169,6 +169,7 @@ struct ceph_osd_request { unsigned int r_num_ops; int r_result; + bool r_abort_on_full; /* return ENOSPC when full */ struct ceph_osd_client *r_osdc; struct kref r_kref; diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c index 5c0938ddddf6..8fc0ccc7126f 100644 --- a/net/ceph/osd_client.c +++ b/net/ceph/osd_client.c @@ -49,6 +49,7 @@ static void link_linger(struct ceph_osd *osd, struct ceph_osd_linger_request *lreq); static void unlink_linger(struct ceph_osd *osd, struct ceph_osd_linger_request *lreq); +static void complete_request(struct ceph_osd_request *req, int err); #if 1 static inline bool rwsem_is_wrlocked(struct rw_semaphore *sem) @@ -961,6 +962,7 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc, truncate_size, truncate_seq); } + req->r_abort_on_full = true; req->r_flags = flags; req->r_base_oloc.pool = layout->pool_id; req->r_base_oloc.pool_ns = ceph_try_get_string(layout->pool_ns); @@ -1635,6 +1637,7 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) enum calc_target_result ct_res; bool need_send = false; bool promoted = false; + int ret = 0; WARN_ON(req->r_tid); dout("%s req %p wrlocked %d\n", __func__, req, wrlocked); @@ -1669,6 +1672,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) pr_warn_ratelimited("FULL or reached pool quota\n"); req->r_t.paused = true; maybe_request_map(osdc); + if (req->r_abort_on_full) + ret = -ENOSPC; } else if (!osd_homeless(osd)) { need_send = true; } else { @@ -1685,6 +1690,8 @@ static void __submit_request(struct ceph_osd_request *req, bool wrlocked) link_request(osd, req); if (need_send) send_request(req); + else if (ret) + complete_request(req, ret); mutex_unlock(&osd->lock); if (ct_res == CALC_TARGET_POOL_DNE)
Usually, when the osd map is flagged as full or the pool is at quota, write requests just hang. This is not what we want for cephfs, where it would be better to simply report -ENOSPC back to userland instead of stalling. If the caller knows that it will want an immediate error return instead of blocking on a full or at-quota error condition then allow it to set a flag to request that behavior. Set that flag in ceph_osdc_new_request (since ceph.ko is the only caller), and on any other write request from ceph.ko. A later patch will deal with requests that were submitted before the new map showing the full condition came in. Signed-off-by: Jeff Layton <jlayton@redhat.com> --- fs/ceph/addr.c | 1 + fs/ceph/file.c | 1 + include/linux/ceph/osd_client.h | 1 + net/ceph/osd_client.c | 7 +++++++ 4 files changed, 10 insertions(+)