[PATCHv3 1/5] lib/genalloc.c: Add power aligned algorithm
From: Will Deacon <hidden>
Date: 2014-06-20 09:34:15
Also in:
linux-mm, lkml
Hi Laura, On Tue, Jun 17, 2014 at 02:39:21AM +0100, Laura Abbott wrote:
One of the more common algorithms used for allocation is to align the start address of the allocation to the order of size requested. Add this as an algorithm option for genalloc.
Good idea, I didn't know this even existed!
quoted hunk ↗ jump to hunk
Signed-off-by: Laura Abbott <redacted> --- include/linux/genalloc.h | 4 ++++ lib/genalloc.c | 21 +++++++++++++++++++++ 2 files changed, 25 insertions(+)diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h index 1c2fdaa..3cd0934 100644 --- a/include/linux/genalloc.h +++ b/include/linux/genalloc.h@@ -110,6 +110,10 @@ extern void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo, extern unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data); +extern unsigned long gen_pool_first_fit_order_align(unsigned long *map, + unsigned long size, unsigned long start, unsigned int nr, + void *data); + extern unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data);diff --git a/lib/genalloc.c b/lib/genalloc.c index bdb9a45..9758529 100644 --- a/lib/genalloc.c +++ b/lib/genalloc.c@@ -481,6 +481,27 @@ unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size, EXPORT_SYMBOL(gen_pool_first_fit); /** + * gen_pool_first_fit_order_align - find the first available region + * of memory matching the size requirement. The region will be aligned + * to the order of the size specified. + * @map: The address to base the search on + * @size: The bitmap size in bits + * @start: The bitnumber to start searching at + * @nr: The number of zeroed bits we're looking for + * @data: additional data - unused
It doesn't look unused to me.
+ */
+unsigned long gen_pool_first_fit_order_align(unsigned long *map,
+ unsigned long size, unsigned long start,
+ unsigned int nr, void *data)
+{
+ unsigned long order = (unsigned long) data;
+ unsigned long align_mask = (1 << get_order(nr << order)) - 1;Why isn't the order just order? Will