Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > The PG_fscache bit waiting functions are completely crazy. The comment > about "this will wake up others" is actively wrong, You mean this? /** * unlock_page_fscache - Unlock a page pinned with PG_fscache * @page: The page * * Unlocks the page and wakes up sleepers in wait_on_page_fscache(). Also * wakes those waiting for the lock and writeback bits because the wakeup * mechanism is shared. But that's OK - those sleepers will just go back to * sleep. */ Actually, you're right. The wakeup check func is evaluated by the waker-upper. I can fix the comment with a patch. > and the waiting function looks insane, because you're mixing the two names > for "fscache" which makes the code look totally incomprehensible. Why would > we wait for PF_fscache, when PG_private_2 was set? Yes, I know why, but the > code looks entirely nonsensical. IIRC someone insisted that I should make it a generic name and put the accessor functions in the fscache headers (which means they aren't available to core code), but I don't remember who (maybe Andrew? it was before mid-2007) - kind of like PG_checked is an alias for PG_owner_priv_1. I'd be quite happy to move the accessors for PG_fscache to the linux/page-flags.h as that would simplify things. David
