Commit 08b8a044 authored by Jeff Layton's avatar Jeff Layton Committed by Ilya Dryomov
Browse files

libceph: add spinlock around osd->o_requests 



In a later patch, we're going to need to search for a request in
the rbtree, but taking the o_mutex is inconvenient as we already
hold the con mutex at the point where we need it.

Add a new spinlock that we take when inserting and erasing entries from
the o_requests tree. Search of the rbtree can be done with either the
mutex or the spinlock, but insertion and removal requires both.

Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
Reviewed-by: default avatarXiubo Li <xiubli@redhat.com>
Reviewed-and-tested-by: default avatarLuís Henriques <lhenriques@suse.de>
Reviewed-by: default avatarMilind Changire <mchangir@redhat.com>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent 706a7415

include/linux/ceph/osd_client.h

+7 −1
Original line number Diff line number Diff line
@@ -29,7 +29,12 @@ typedef void (*ceph_osdc_callback_t)(struct ceph_osd_request *); 


#define CEPH_HOMELESS_OSD	-1



/* a given osd we're communicating with */

/*

 * A given osd we're communicating with.

 *

 * Note that the o_requests tree can be searched while holding the "lock" mutex

 * or the "o_requests_lock" spinlock. Insertion or removal requires both!

 */

struct ceph_osd {

	refcount_t o_ref;

	struct ceph_osd_client *o_osdc;
@@ -37,6 +42,7 @@ struct ceph_osd { 
	int o_incarnation;

	struct rb_node o_node;

	struct ceph_connection o_con;

	spinlock_t o_requests_lock;

	struct rb_root o_requests;

	struct rb_root o_linger_requests;

	struct rb_root o_backoff_mappings;

net/ceph/osd_client.c

+5 −0
Original line number Diff line number Diff line
@@ -1177,6 +1177,7 @@ static void osd_init(struct ceph_osd *osd) 
{

	refcount_set(&osd->o_ref, 1);

	RB_CLEAR_NODE(&osd->o_node);

	spin_lock_init(&osd->o_requests_lock);

	osd->o_requests = RB_ROOT;

	osd->o_linger_requests = RB_ROOT;

	osd->o_backoff_mappings = RB_ROOT;
@@ -1406,7 +1407,9 @@ static void link_request(struct ceph_osd *osd, struct ceph_osd_request *req) 
		atomic_inc(&osd->o_osdc->num_homeless);



	get_osd(osd);

	spin_lock(&osd->o_requests_lock);

	insert_request(&osd->o_requests, req);

	spin_unlock(&osd->o_requests_lock);

	req->r_osd = osd;

}
@@ -1418,7 +1421,9 @@ static void unlink_request(struct ceph_osd *osd, struct ceph_osd_request *req) 
	     req, req->r_tid);



	req->r_osd = NULL;

	spin_lock(&osd->o_requests_lock);

	erase_request(&osd->o_requests, req);

	spin_unlock(&osd->o_requests_lock);

	put_osd(osd);



	if (!osd_homeless(osd))