From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Subject: Re: [PATCH 6/6] mm: Add memalloc_nowait Date: Mon, 29 Jun 2020 16:45:14 +0300 Message-ID: <6421BC93-CF2F-4697-B5CB-5ECDAA9FCB37@kernel.org> References: <20200625113122.7540-1-willy@infradead.org> <20200625113122.7540-7-willy@infradead.org> <20200629050851.GC1492837@kernel.org> <20200629121816.GC25523@casper.infradead.org> <20200629125231.GJ32461@dhcp22.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20200629125231.GJ32461@dhcp22.suse.cz> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Michal Hocko , Matthew Wilcox Cc: Jens Axboe , linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, dm-devel@redhat.com, Mikulas Patocka List-Id: dm-devel.ids On June 29, 2020 3:52:31 PM GMT+03:00, Michal Hocko wrote: >On Mon 29-06-20 13:18:16, Matthew Wilcox wrote: >> On Mon, Jun 29, 2020 at 08:08:51AM +0300, Mike Rapoport wrote: >> > > @@ -886,8 +868,12 @@ static struct dm_buffer >*__alloc_buffer_wait_no_callback(struct dm_bufio_client >> > > return NULL; >> > > >> > > if (dm_bufio_cache_size_latch != 1 && !tried_noio_alloc) { >> > > + unsigned noio_flag; >> > > + >> > > dm_bufio_unlock(c); >> > > - b = alloc_buffer(c, GFP_NOIO | __GFP_NORETRY | >__GFP_NOMEMALLOC | __GFP_NOWARN); >> > > + noio_flag = memalloc_noio_save(); >> > >> > I've read the series twice and I'm still missing the definition of >> > memalloc_noio_save(). >> > >> > And also it would be nice to have a paragraph about it in >> > Documentation/core-api/memory-allocation.rst >> >> >Documentation/core-api/gfp_mask-from-fs-io.rst:``memalloc_nofs_save``, >``memalloc_nofs_restore`` respectively ``memalloc_noio_save``, >> Documentation/core-api/gfp_mask-from-fs-io.rst: :functions: >memalloc_noio_save memalloc_noio_restore >> Documentation/core-api/gfp_mask-from-fs-io.rst:allows nesting so it >is safe to call ``memalloc_noio_save`` or > >The patch is adding memalloc_nowait* and I suspect Mike had that in >mind, which would be a fair request. Right, sorry misprinted that. > Btw. we are missing >memalloc_nocma* >documentation either - I was just reminded of its existence today.. -- Sincerely yours, Mike