[lkml]   [2009]   [Apr]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 23/43] CacheFiles: Permit the page lock state to be monitored [ver #46]
On Thursday 02 April 2009 10:05:20 David Howells wrote:
> Add a function to install a monitor on the page lock waitqueue for a particular
> page, thus allowing the page being unlocked to be detected.
> This is used by CacheFiles to detect read completion on a page in the backing
> filesystem so that it can then copy the data to the waiting netfs page.

I prefer to nack this because it is exporting details of the page
locking mechanism. unlock_page is very heavyweight in large part
because of the memory barriers and cacheline required to check the
waitqueue. I have patches to avoid all that if the page lock is
not contended.

What's wrong with using wait_on_page_locked, like everyone else does?

 \ /
  Last update: 2009-04-02 17:41    [W:0.160 / U:3.144 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site