From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751576AbeA2QbV (ORCPT ); Mon, 29 Jan 2018 11:31:21 -0500 Received: from mx2.suse.de ([195.135.220.15]:55035 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751542AbeA2QbR (ORCPT ); Mon, 29 Jan 2018 11:31:17 -0500 Date: Mon, 29 Jan 2018 17:31:14 +0100 From: Michal Hocko To: Roger He Cc: dri-devel@lists.freedesktop.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christian.Koenig@amd.com Subject: Re: [PATCH] mm/swap: add function get_total_swap_pages to expose total_swap_pages Message-ID: <20180129163114.GH21609@dhcp22.suse.cz> References: <1517214582-30880-1-git-send-email-Hongbo.He@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1517214582-30880-1-git-send-email-Hongbo.He@amd.com> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 29-01-18 16:29:42, Roger He wrote: > ttm module needs it to determine its internal parameter setting. Could you be more specific why? > Signed-off-by: Roger He > --- > include/linux/swap.h | 6 ++++++ > mm/swapfile.c | 15 +++++++++++++++ > 2 files changed, 21 insertions(+) > > diff --git a/include/linux/swap.h b/include/linux/swap.h > index c2b8128..708d66f 100644 > --- a/include/linux/swap.h > +++ b/include/linux/swap.h > @@ -484,6 +484,7 @@ extern int try_to_free_swap(struct page *); > struct backing_dev_info; > extern int init_swap_address_space(unsigned int type, unsigned long nr_pages); > extern void exit_swap_address_space(unsigned int type); > +extern long get_total_swap_pages(void); > > #else /* CONFIG_SWAP */ > > @@ -516,6 +517,11 @@ static inline void show_swap_cache_info(void) > { > } > > +long get_total_swap_pages(void) > +{ > + return 0; > +} > + > #define free_swap_and_cache(e) ({(is_migration_entry(e) || is_device_private_entry(e));}) > #define swapcache_prepare(e) ({(is_migration_entry(e) || is_device_private_entry(e));}) > > diff --git a/mm/swapfile.c b/mm/swapfile.c > index 3074b02..a0062eb 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -98,6 +98,21 @@ static atomic_t proc_poll_event = ATOMIC_INIT(0); > > atomic_t nr_rotate_swap = ATOMIC_INIT(0); > > +/* > + * expose this value for others use > + */ > +long get_total_swap_pages(void) > +{ > + long ret; > + > + spin_lock(&swap_lock); > + ret = total_swap_pages; > + spin_unlock(&swap_lock); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(get_total_swap_pages); > + > static inline unsigned char swap_count(unsigned char ent) > { > return ent & ~SWAP_HAS_CACHE; /* may include SWAP_HAS_CONT flag */ > -- > 2.7.4 -- Michal Hocko SUSE Labs