On Mon, Sep 25, 2000 at 11:51:39AM -0600, yodaiken@fsmlabs.com wrote:
> It should probably be GFP_ATOMIC, if I understand the mm right.
poll_wait is called from the f_op->poll callback from select just before
a sleep and since it's allowed to sleep too it should be a GFP_KERNEL
(not ATOMIC). Using GFP_ATOMIC where GFP_KERNEL can be used is a bug
and it can lead to failed allocations even while there's huge amount
of freeable/recyclable cache.
The reason it isn't GFP_USER but it's a GFP_KERNEL is because the memory
isn't allocated in userspace.
On a solid VM the only difference between GFP_USER and GFP_KERNEL happens to be
when the machine runs truly out of memory. In 2.4.x GFP_KERNEL should probably
be changed not to short the PF_MEMALLOC atomic queue when memory balancing
fails (then they would be equal).
> The algorithm for requesting a collection of reources and freeing all of them
> on failure is simple, fast, and robust.
Yes, I tend to like that style too because it's obviously safe and it obviously
can't dealdock during oom.
Andrea
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sat Sep 30 2000 - 21:00:15 EST