Messages in this thread |  | | | From | David Howells <> | | Subject | Re: [RFC] get_write_access()/deny_write_access() without inode->i_lock | | Date | Mon, 20 Jun 2011 13:47:17 +0100 |
| |
Al Viro <viro@ZenIV.linux.org.uk> wrote:
> + for (v = atomic_read(&inode->i_writecount); v >= 0; v = v1) { > + v1 = atomic_cmpxchg(&inode->i_writecount, v, v + 1); > + if (likely(v1 == v)) > + return 0; > + }
You don't need to reissue the atomic_read(). atomic_cmpxchg() returns the current value of the memory location. Just set v to v1 before going round the loop again.
David
|  |