Commit 558b4510 authored by Xiubo Li's avatar Xiubo Li Committed by Ilya Dryomov
Browse files

ceph: defer flushing the capsnap if the Fb is used 

If the Fb cap is used it means the current inode is flushing the
dirty data to OSD, just defer flushing the capsnap.

URL: https://tracker.ceph.com/issues/48640


Signed-off-by: default avatarXiubo Li <xiubli@redhat.com>
Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent d7ef2e59

fs/ceph/caps.c

+20 −13
Original line number Diff line number Diff line
@@ -3047,6 +3047,7 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had, 
{

	struct inode *inode = &ci->vfs_inode;

	int last = 0, put = 0, flushsnaps = 0, wake = 0;

	bool check_flushsnaps = false;



	spin_lock(&ci->i_ceph_lock);

	if (had & CEPH_CAP_PIN)
@@ -3063,26 +3064,17 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had, 
	if (had & CEPH_CAP_FILE_BUFFER) {

		if (--ci->i_wb_ref == 0) {

			last++;

			/* put the ref held by ceph_take_cap_refs() */

			put++;

			check_flushsnaps = true;

		}

		dout("put_cap_refs %p wb %d -> %d (?)\n",

		     inode, ci->i_wb_ref+1, ci->i_wb_ref);

	}

	if (had & CEPH_CAP_FILE_WR)

	if (had & CEPH_CAP_FILE_WR) {

		if (--ci->i_wr_ref == 0) {

			last++;

			if (__ceph_have_pending_cap_snap(ci)) {

				struct ceph_cap_snap *capsnap =

					list_last_entry(&ci->i_cap_snaps,

							struct ceph_cap_snap,

							ci_item);

				capsnap->writing = 0;

				if (ceph_try_drop_cap_snap(ci, capsnap))

					put++;

				else if (__ceph_finish_cap_snap(ci, capsnap))

					flushsnaps = 1;

				wake = 1;

			}

			check_flushsnaps = true;

			if (ci->i_wrbuffer_ref_head == 0 &&

			    ci->i_dirty_caps == 0 &&

			    ci->i_flushing_caps == 0) {
@@ -3094,6 +3086,21 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had, 
			if (!__ceph_is_any_real_caps(ci) && ci->i_snap_realm)

				drop_inode_snap_realm(ci);

		}

	}

	if (check_flushsnaps && __ceph_have_pending_cap_snap(ci)) {

		struct ceph_cap_snap *capsnap =

			list_last_entry(&ci->i_cap_snaps,

					struct ceph_cap_snap,

					ci_item);



		capsnap->writing = 0;

		if (ceph_try_drop_cap_snap(ci, capsnap))

			/* put the ref held by ceph_queue_cap_snap() */

			put++;

		else if (__ceph_finish_cap_snap(ci, capsnap))

			flushsnaps = 1;

		wake = 1;

	}

	spin_unlock(&ci->i_ceph_lock);



	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),

fs/ceph/snap.c

+10 −0
Original line number Diff line number Diff line
@@ -623,6 +623,16 @@ int __ceph_finish_cap_snap(struct ceph_inode_info *ci, 
		return 0;

	}



	/* Fb cap still in use, delay it */

	if (ci->i_wb_ref) {

		dout("finish_cap_snap %p cap_snap %p snapc %p %llu %s s=%llu "

		     "used WRBUFFER, delaying\n", inode, capsnap,

		     capsnap->context, capsnap->context->seq,

		     ceph_cap_string(capsnap->dirty), capsnap->size);

		capsnap->writing = 1;

		return 0;

	}



	ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;

	dout("finish_cap_snap %p cap_snap %p snapc %p %llu %s s=%llu\n",

	     inode, capsnap, capsnap->context,