Commit d6c2f41e authored by Simon Buttgereit's avatar Simon Buttgereit Committed by Ilya Dryomov
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libceph: fix log output race condition in OSD client 



OSD client logging has a problem in get_osd() and put_osd().
For one logging output refcount_read() is called twice. If recount
value changes between both calls logging output is not consistent.

This patch prints out only the resulting value.

[ idryomov: don't make the log messages more verbose ]

Signed-off-by: default avatarSimon Buttgereit <simon.buttgereit@tu-ilmenau.de>
Reviewed-by: default avatarViacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent 7d0a66e4

net/ceph/osd_client.c

+2 −4
Original line number Diff line number Diff line
@@ -1280,8 +1280,7 @@ static struct ceph_osd *create_osd(struct ceph_osd_client *osdc, int onum) 
static struct ceph_osd *get_osd(struct ceph_osd *osd)

{

	if (refcount_inc_not_zero(&osd->o_ref)) {

		dout("get_osd %p %d -> %d\n", osd, refcount_read(&osd->o_ref)-1,

		     refcount_read(&osd->o_ref));

		dout("get_osd %p -> %d\n", osd, refcount_read(&osd->o_ref));

		return osd;

	} else {

		dout("get_osd %p FAIL\n", osd);
@@ -1291,8 +1290,7 @@ static struct ceph_osd *get_osd(struct ceph_osd *osd) 


static void put_osd(struct ceph_osd *osd)

{

	dout("put_osd %p %d -> %d\n", osd, refcount_read(&osd->o_ref),

	     refcount_read(&osd->o_ref) - 1);

	dout("put_osd %p -> %d\n", osd, refcount_read(&osd->o_ref) - 1);

	if (refcount_dec_and_test(&osd->o_ref)) {

		osd_cleanup(osd);

		kfree(osd);