[email protected] (Dean Nelson) wrote:
>
>
> The following patch modifies the gen_pool allocator (lib/genalloc.c) to
> utilize a bitmap scheme instead of the buddy scheme. The purpose of this
> change is to eliminate the touching of the actual memory being allocated.
>
> Since the change modifies the interface, a change to the uncached
> allocator (arch/ia64/kernel/uncached.c) is also required.
>
> Signed-off-by: Dean Nelson <[email protected]>
>
> ---
>
> Andrew,
>
> Both Andrey Volkov and Jes Sorenson have expressed a desire that the
> gen_pool allocator not write to the memory being managed. See the
> following:
>
> http://marc.theaimsgroup.com/?l=linux-kernel&m=113518602713125&w=2
> http://marc.theaimsgroup.com/?l=linux-kernel&m=113533568827916&w=2
hm, fair enough.
The patch is fairly large+intrusive. I trust it's been broadly tested?
> -unsigned long gen_pool_alloc(struct gen_pool *poolp, int size)
> +int gen_pool_add(struct gen_pool *pool, unsigned long addr, size_t size,
> + int nid)
> {
> - int j, i, s, max_chunk_size;
> - unsigned long a, flags;
> - struct gen_pool_link *h = poolp->h;
> + struct gen_pool_chunk *chunk;
> + int nbits = size >> pool->min_alloc_order;
> + int nbytes = sizeof(struct gen_pool_chunk) + nbits / 8;
We can use BITS_PER_BYTE rather than "8".
I have a suspicion that `nbytes' here needs to be rounded up.
> + if (nbytes > PAGE_SIZE) {
> + if (nid == GENALLOC_NID_NONE)
> + chunk = vmalloc(nbytes);
> + else
> + chunk = vmalloc_node(nbytes, nid);
> + } else {
> + if (nid == GENALLOC_NID_NONE)
> + chunk = kmalloc(nbytes, GFP_KERNEL);
> + else
> + chunk = kmalloc_node(nbytes, GFP_KERNEL, nid);
> + }
I don't think GENALLOC_NID_NONE needs to exist. If the caller passes in
`nid=-1', kmalloc_node() will do what you want.
Which is an apparently-undocumented feature...
-
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/
[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]
