Re: [PATCH v4 19/19] fs: handle inode->i_version more efficiently

Matthew Wilcox
2018-01-08T13:30:39Z

On Fri, Dec 22, 2017 at 07:05:56AM -0500, Jeff Layton wrote:
> + cur = inode_peek_iversion_raw(inode);
> + for (;;) {
> + /* If flag is clear then we needn't do anything */
> + if (!force && !(cur & I_VERSION_QUERIED))
> + return false;
> + /* Since lowest bit is flag, add 2 to avoid it */
> + new = (cur & ~I_VERSION_QUERIED) + I_VERSION_INCREMENT;

Isn't this an extraordinarily complicated way of spelling:

new = cur + 1;

We know 'cur' has I_VERSION_QUERIED set, so clearing that bit and adding
two is going to be the same as adding 1 ... right?