Re: [patch 1/7] allocpercpu: Make it a true per cpu allocator by allocating from a per cpu array

On Thu, 1 Nov 2007, Eric Dumazet wrote:

> Christoph Lameter a écrit :
> > +
> > +enum unit_type { FREE, END, USED };
> > +
> > +static u8 cpu_alloc_map[UNITS_PER_CPU] = { 1, };
> 
> You mean END here instead of 1 :)

Sigh. A leftover. This can be removed.

> > +/*
> > + * Allocate an object of a certain size
> > + *
> > + * Returns a per cpu pointer that must not be directly used.
> > + */
> > +static void *cpu_alloc(unsigned long size)
> > +{
> 
> We might need to give an alignment constraint here. Some per_cpu users would
> like to get a 64 bytes zone, siting in one cache line and not two :)

Well not sure about that. Alignment is mostly useful on SMP with cacheline 
contention. This is a per cpu area that should not be contended.

---

• References:
  • [patch 0/7] [RFC] SLUB: Improve allocpercpu to reduce per cpu access overhead
    • From: Christoph Lameter <[email protected]>
  • [patch 1/7] allocpercpu: Make it a true per cpu allocator by allocating from a per cpu array
    • From: Christoph Lameter <[email protected]>
  • Re: [patch 1/7] allocpercpu: Make it a true per cpu allocator by allocating from a per cpu array
    • From: Eric Dumazet <[email protected]>

• Prev by Date: Re: [patch 0/7] [RFC] SLUB: Improve allocpercpu to reduce per cpu access overhead
• Next by Date: Re: [patch 0/7] [RFC] SLUB: Improve allocpercpu to reduce per cpu access overhead
• Previous by thread: Re: [patch 1/7] allocpercpu: Make it a true per cpu allocator by allocating from a per cpu array
• Next by thread: Re: [patch 0/7] [RFC] SLUB: Improve allocpercpu to reduce per cpu access overhead
• 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]