Re: Introduce atomic_dec_and_lock_irqsave()
From: Al Viro <viro@ZenIV.linux.org.uk>
Date: 2018-05-04 16:26:47
Also in:
linux-mm, lkml
On Fri, May 04, 2018 at 06:21:02PM +0200, Peter Zijlstra wrote:
On Fri, May 04, 2018 at 06:07:26PM +0200, Sebastian Andrzej Siewior wrote:quoted
do you intend to kill refcount_dec_and_lock() in the longterm?You meant to say atomic_dec_and_lock() ? Dunno if we ever get there, but typically dec_and_lock is fairly refcounty, but I suppose it is possible to have !refcount users, in which case we're eternally stuck with it.
Yes, there are - consider e.g.
void iput(struct inode *inode)
{
if (!inode)
return;
BUG_ON(inode->i_state & I_CLEAR);
retry:
if (atomic_dec_and_lock(&inode->i_count, &inode->i_lock)) {
inode->i_count sure as hell isn't refcount_t fodder...