Re: [PATCH -mm] slub: update cpu after new_slab()

On Wed, 25 Apr 2007, Hugh Dickins wrote:

> > Right. local_irq_save does not switch off preemption as I thought.
> 
> Strange comment.  Preemption is not possible while IRQs are disabled,
> but new_slab() rightly reenables them within itself in the __GFP_WAIT
> case, since it's going off to do a page allocation and may need to wait.

Yes I expected local_irq_save to increase the preempt count and then 
local_irq_enable to simply enable interrupts without affecting the preempt 
count. Thus the process should stay on the same processor.

Never thought it would be possible to move to a different processor in mid 
flight.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

---

• Follow-Ups:
  • Re: [PATCH -mm] slub: update cpu after new_slab()
    • From: Hugh Dickins <[email protected]>

• References:
  • [PATCH -mm] slub: update cpu after new_slab()
    • From: Hugh Dickins <[email protected]>
  • Re: [PATCH -mm] slub: update cpu after new_slab()
    • From: Christoph Lameter <[email protected]>
  • Re: [PATCH -mm] slub: update cpu after new_slab()
    • From: Hugh Dickins <[email protected]>

• Prev by Date: Re: [PATCH 5/15] cfq-iosched: speed up rbtree handling
• Next by Date: [PATCH 04/16] AF_RXRPC: Make it possible to merely try to cancel timers from a module [try #4]
• Previous by thread: Re: [PATCH -mm] slub: update cpu after new_slab()
• Next by thread: Re: [PATCH -mm] slub: update cpu after new_slab()
• Index(es):
  • Date
  • Thread

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]