From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f178.google.com (mail-pd0-f178.google.com [209.85.192.178]) by kanga.kvack.org (Postfix) with ESMTP id 580B26B0035 for ; Thu, 21 Aug 2014 19:17:21 -0400 (EDT) Received: by mail-pd0-f178.google.com with SMTP id w10so14655858pde.23 for ; Thu, 21 Aug 2014 16:17:21 -0700 (PDT) Received: from mail-pd0-x232.google.com (mail-pd0-x232.google.com [2607:f8b0:400e:c02::232]) by mx.google.com with ESMTPS id a2si38378806pdn.27.2014.08.21.16.17.20 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 21 Aug 2014 16:17:20 -0700 (PDT) Received: by mail-pd0-f178.google.com with SMTP id w10so14900818pde.37 for ; Thu, 21 Aug 2014 16:17:19 -0700 (PDT) Date: Thu, 21 Aug 2014 23:22:15 +0000 From: Minchan Kim Subject: Re: [PATCH v3 2/4] zsmalloc: change return value unit of zs_get_total_size_bytes Message-ID: <20140821232215.GF10703@gmail.com> References: <1408580838-29236-1-git-send-email-minchan@kernel.org> <1408580838-29236-3-git-send-email-minchan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Dan Streetman Cc: Andrew Morton , Linux-MM , linux-kernel , Sergey Senozhatsky , Jerome Marchand , juno.choi@lge.com, seungho1.park@lge.com, Luigi Semenzato , Nitin Gupta , Seth Jennings , David Horner Hi Dan, On Thu, Aug 21, 2014 at 02:53:57PM -0400, Dan Streetman wrote: > On Wed, Aug 20, 2014 at 8:27 PM, Minchan Kim wrote: > > zs_get_total_size_bytes returns a amount of memory zsmalloc > > consumed with *byte unit* but zsmalloc operates *page unit* > > rather than byte unit so let's change the API so benefit > > we could get is that reduce unnecessary overhead > > (ie, change page unit with byte unit) in zsmalloc. > > > > Now, zswap can rollback to zswap_pool_pages. > > Over to zswap guys ;-) > > We could change zpool/zswap over to total pages instead of total > bytes, since both zbud and zsmalloc now report size in pages. The > only downside would be if either changed later to not use only whole > pages (or if they start using huge pages for storage...), but for what > they do that seems unlikely. After this patch is finalized I can > write up a quick patch unless Seth disagrees (or already has a patch > :) That's extactly what I mentioned zswap in this patch. Now that you guys notice my intention, I will remove zswap part in description in next revision. Thanks. > > > > > Signed-off-by: Minchan Kim > > --- > > drivers/block/zram/zram_drv.c | 4 ++-- > > include/linux/zsmalloc.h | 2 +- > > mm/zsmalloc.c | 10 +++++----- > > 3 files changed, 8 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > > index d00831c3d731..302dd37bcea3 100644 > > --- a/drivers/block/zram/zram_drv.c > > +++ b/drivers/block/zram/zram_drv.c > > @@ -103,10 +103,10 @@ static ssize_t mem_used_total_show(struct device *dev, > > > > down_read(&zram->init_lock); > > if (init_done(zram)) > > - val = zs_get_total_size_bytes(meta->mem_pool); > > + val = zs_get_total_size(meta->mem_pool); > > up_read(&zram->init_lock); > > > > - return scnprintf(buf, PAGE_SIZE, "%llu\n", val); > > + return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT); > > } > > > > static ssize_t max_comp_streams_show(struct device *dev, > > diff --git a/include/linux/zsmalloc.h b/include/linux/zsmalloc.h > > index e44d634e7fb7..105b56e45d23 100644 > > --- a/include/linux/zsmalloc.h > > +++ b/include/linux/zsmalloc.h > > @@ -46,6 +46,6 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle, > > enum zs_mapmode mm); > > void zs_unmap_object(struct zs_pool *pool, unsigned long handle); > > > > -u64 zs_get_total_size_bytes(struct zs_pool *pool); > > +unsigned long zs_get_total_size(struct zs_pool *pool); > > minor naming suggestion, but since the name is changing anyway, > "zs_get_total_size" implies to me the units are bytes, would > "zs_get_total_pages" be clearer that it's returning size in # of > pages, not bytes? > > > > > #endif > > diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > > index a65924255763..80408a1da03a 100644 > > --- a/mm/zsmalloc.c > > +++ b/mm/zsmalloc.c > > @@ -299,7 +299,7 @@ static void zs_zpool_unmap(void *pool, unsigned long handle) > > > > static u64 zs_zpool_total_size(void *pool) > > { > > - return zs_get_total_size_bytes(pool); > > + return zs_get_total_size(pool) << PAGE_SHIFT; > > } > > > > static struct zpool_driver zs_zpool_driver = { > > @@ -1186,16 +1186,16 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle) > > } > > EXPORT_SYMBOL_GPL(zs_unmap_object); > > > > -u64 zs_get_total_size_bytes(struct zs_pool *pool) > > +unsigned long zs_get_total_size(struct zs_pool *pool) > > { > > - u64 npages; > > + unsigned long npages; > > > > spin_lock(&pool->stat_lock); > > npages = pool->pages_allocated; > > spin_unlock(&pool->stat_lock); > > - return npages << PAGE_SHIFT; > > + return npages; > > } > > -EXPORT_SYMBOL_GPL(zs_get_total_size_bytes); > > +EXPORT_SYMBOL_GPL(zs_get_total_size); > > > > module_init(zs_init); > > module_exit(zs_exit); > > -- > > 2.0.0 > > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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