Commit 3e7fbe9c authored by Yan, Zheng's avatar Yan, Zheng
Browse files

ceph: introduce ceph_fill_fragtree() 



Move the code that update the i_fragtree into a separate function.
Also add simple probabilistic test to decide whether the i_fragtree
should be updated

Signed-off-by: default avatarYan, Zheng <zheng.z.yan@intel.com>
parent 2cd698be

fs/ceph/inode.c

+84 −45
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
#include <linux/writeback.h>

#include <linux/vmalloc.h>

#include <linux/posix_acl.h>

#include <linux/random.h>



#include "super.h"

#include "mds_client.h"
@@ -179,9 +180,8 @@ struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci, u32 f) 
 * specified, copy the frag delegation info to the caller if

 * it is present.

 */

u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,

		     struct ceph_inode_frag *pfrag,

		     int *found)

static u32 __ceph_choose_frag(struct ceph_inode_info *ci, u32 v,

			      struct ceph_inode_frag *pfrag, int *found)

{

	u32 t = ceph_frag_make(0, 0);

	struct ceph_inode_frag *frag;
@@ -191,7 +191,6 @@ u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v, 
	if (found)

		*found = 0;



	mutex_lock(&ci->i_fragtree_mutex);

	while (1) {

		WARN_ON(!ceph_frag_contains_value(t, v));

		frag = __ceph_find_frag(ci, t);
@@ -220,10 +219,19 @@ u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v, 
	}

	dout("choose_frag(%x) = %x\n", v, t);



	mutex_unlock(&ci->i_fragtree_mutex);

	return t;

}



u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,

		     struct ceph_inode_frag *pfrag, int *found)

{

	u32 ret;

	mutex_lock(&ci->i_fragtree_mutex);

	ret = __ceph_choose_frag(ci, v, pfrag, found);

	mutex_unlock(&ci->i_fragtree_mutex);

	return ret;

}



/*

 * Process dirfrag (delegation) info from the mds.  Include leaf

 * fragment in tree ONLY if ndist > 0.  Otherwise, only
@@ -286,6 +294,75 @@ static int ceph_fill_dirfrag(struct inode *inode, 
	return err;

}



static int ceph_fill_fragtree(struct inode *inode,

			      struct ceph_frag_tree_head *fragtree,

			      struct ceph_mds_reply_dirfrag *dirinfo)

{

	struct ceph_inode_info *ci = ceph_inode(inode);

	struct ceph_inode_frag *frag;

	struct rb_node *rb_node;

	int i;

	u32 id, nsplits;

	bool update = false;



	mutex_lock(&ci->i_fragtree_mutex);

	nsplits = le32_to_cpu(fragtree->nsplits);

	if (nsplits) {

		i = prandom_u32() % nsplits;

		id = le32_to_cpu(fragtree->splits[i].frag);

		if (!__ceph_find_frag(ci, id))

			update = true;

	} else if (!RB_EMPTY_ROOT(&ci->i_fragtree)) {

		rb_node = rb_first(&ci->i_fragtree);

		frag = rb_entry(rb_node, struct ceph_inode_frag, node);

		if (frag->frag != ceph_frag_make(0, 0) || rb_next(rb_node))

			update = true;

	}

	if (!update && dirinfo) {

		id = le32_to_cpu(dirinfo->frag);

		if (id != __ceph_choose_frag(ci, id, NULL, NULL))

			update = true;

	}

	if (!update)

		goto out_unlock;



	dout("fill_fragtree %llx.%llx\n", ceph_vinop(inode));

	rb_node = rb_first(&ci->i_fragtree);

	for (i = 0; i < nsplits; i++) {

		id = le32_to_cpu(fragtree->splits[i].frag);

		frag = NULL;

		while (rb_node) {

			frag = rb_entry(rb_node, struct ceph_inode_frag, node);

			if (ceph_frag_compare(frag->frag, id) >= 0) {

				if (frag->frag != id)

					frag = NULL;

				else

					rb_node = rb_next(rb_node);

				break;

			}

			rb_node = rb_next(rb_node);

			rb_erase(&frag->node, &ci->i_fragtree);

			kfree(frag);

			frag = NULL;

		}

		if (!frag) {

			frag = __get_or_create_frag(ci, id);

			if (IS_ERR(frag))

				continue;

		}

		frag->split_by = le32_to_cpu(fragtree->splits[i].by);

		dout(" frag %x split by %d\n", frag->frag, frag->split_by);

	}

	while (rb_node) {

		frag = rb_entry(rb_node, struct ceph_inode_frag, node);

		rb_node = rb_next(rb_node);

		rb_erase(&frag->node, &ci->i_fragtree);

		kfree(frag);

	}

out_unlock:

	mutex_unlock(&ci->i_fragtree_mutex);

	return 0;

}



/*

 * initialize a newly allocated inode.
@@ -584,12 +661,8 @@ static int fill_inode(struct inode *inode, 
	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;

	struct ceph_mds_reply_inode *info = iinfo->in;

	struct ceph_inode_info *ci = ceph_inode(inode);

	int i;

	int issued = 0, implemented, new_issued;

	struct timespec mtime, atime, ctime;

	u32 nsplits;

	struct ceph_inode_frag *frag;

	struct rb_node *rb_node;

	struct ceph_buffer *xattr_blob = NULL;

	struct ceph_cap *new_cap = NULL;

	int err = 0;
@@ -804,42 +877,8 @@ static int fill_inode(struct inode *inode, 
		ceph_queue_vmtruncate(inode);



	/* populate frag tree */

	/* FIXME: move me up, if/when version reflects fragtree changes */

	nsplits = le32_to_cpu(info->fragtree.nsplits);

	mutex_lock(&ci->i_fragtree_mutex);

	rb_node = rb_first(&ci->i_fragtree);

	for (i = 0; i < nsplits; i++) {

		u32 id = le32_to_cpu(info->fragtree.splits[i].frag);

		frag = NULL;

		while (rb_node) {

			frag = rb_entry(rb_node, struct ceph_inode_frag, node);

			if (ceph_frag_compare(frag->frag, id) >= 0) {

				if (frag->frag != id)

					frag = NULL;

				else

					rb_node = rb_next(rb_node);

				break;

			}

			rb_node = rb_next(rb_node);

			rb_erase(&frag->node, &ci->i_fragtree);

			kfree(frag);

			frag = NULL;

		}

		if (!frag) {

			frag = __get_or_create_frag(ci, id);

			if (IS_ERR(frag))

				continue;

		}

		frag->split_by = le32_to_cpu(info->fragtree.splits[i].by);

		dout(" frag %x split by %d\n", frag->frag, frag->split_by);

	}

	while (rb_node) {

		frag = rb_entry(rb_node, struct ceph_inode_frag, node);

		rb_node = rb_next(rb_node);

		rb_erase(&frag->node, &ci->i_fragtree);

		kfree(frag);

	}

	mutex_unlock(&ci->i_fragtree_mutex);

	if (S_ISDIR(inode->i_mode))

		ceph_fill_fragtree(inode, &info->fragtree, dirinfo);



	/* update delegation info? */

	if (dirinfo)