lkml.org 
[lkml]   [2012]   [Dec]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch] bdi: add a user-tunable cpu_list for the bdi flusher threads
On Mon, Dec 03, 2012 at 11:22:31AM -0500, Jeff Moyer wrote:
> Jeff Moyer <jmoyer@redhat.com> writes:
>
> >>> + bdi->flusher_cpumask = kmalloc(sizeof(cpumask_t), GFP_KERNEL);
> >>> + if (!bdi->flusher_cpumask)
> >>> + return -ENOMEM;
> >>
> >> The bare GFP_KERNEL raises an eyebrow. Some bdi_init() callers like
> >> blk_alloc_queue_node() look like they'll want to pass in a gfp_t for the
> >> allocation.
> >
> > I'd be surprised if that was necessary, seeing how every single caller
> > of blk_alloc_queue_node passes in GFP_KERNEL. I'll make the change,
> > though, there aren't too many callers of bdi_init out there.
>
> No other callers of bdi_init want anything but GFP_KERNEL. In the case
> of blk_alloc_queue_node, even *it* doesn't honor the gfp_t passed in!
> Have a look at blkcg_init_queue (called from blk_alloc_queue_node) to
> see what I mean. Maybe that's a bug?

Heh, indeed.

> I've written the patch to modify bdi_init to take a gfp_t, but I'm
> actually not in favor of this change, so I'm not going to post it
> (unless, of course, you can provide a compelling argument). :-)

No argument here, it just jumped out at me in the code. I didn't check
out the callers or history of why it was that way :).

- z


\
 
 \ /
  Last update: 2012-12-03 20:41    [W:0.037 / U:0.660 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site