Messages in this thread | | | Date | Thu, 26 Apr 2012 10:42:48 +0900 | From | Minchan Kim <> | Subject | Re: [PATCH 2/6] zsmalloc: remove unnecessary alignment |
| |
On 04/25/2012 09:53 PM, Nitin Gupta wrote:
> On 04/25/2012 02:23 AM, Minchan Kim wrote: > >> It isn't necessary to align pool size with PAGE_SIZE. >> If I missed something, please let me know it. >> >> Signed-off-by: Minchan Kim <minchan@kernel.org> >> --- >> drivers/staging/zsmalloc/zsmalloc-main.c | 5 ++--- >> 1 file changed, 2 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c >> index 504b6c2..b99ad9e 100644 >> --- a/drivers/staging/zsmalloc/zsmalloc-main.c >> +++ b/drivers/staging/zsmalloc/zsmalloc-main.c >> @@ -489,14 +489,13 @@ fail: >> >> struct zs_pool *zs_create_pool(const char *name, gfp_t flags) >> { >> - int i, error, ovhd_size; >> + int i, error; >> struct zs_pool *pool; >> >> if (!name) >> return NULL; >> >> - ovhd_size = roundup(sizeof(*pool), PAGE_SIZE); >> - pool = kzalloc(ovhd_size, GFP_KERNEL); >> + pool = kzalloc(sizeof(*pool), GFP_KERNEL); >> if (!pool) >> return NULL; >> > > > pool metadata is rounded-up to avoid potential false-sharing problem > (though we could just roundup to cache_line_size()).
Do you really have any hurt by false-sharing problem? If so, we can change it with
kzalloc(ALIGN(sizeof(*pool), cache_line_size()), GFP_KERNEL);
But I am not sure we need this.
> > Thanks, > Nitin > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ > Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >
-- Kind regards, Minchan Kim
| |