From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v3 3/5] bitmap: Add bitmap_alloc(), bitmap_zalloc() and bitmap_free() Date: Fri, 22 Jun 2018 11:46:13 -0700 Message-ID: <20180622184613.GC92912@dtor-ws> References: <20180618131003.88110-1-andriy.shevchenko@linux.intel.com> <20180618131003.88110-4-andriy.shevchenko@linux.intel.com> <20180618141404.68124daab97bd0f3a3051544@linux-foundation.org> <20180618161056.e52efd0e8bd36211e60705a2@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Andy Shevchenko Cc: Andrew Morton , Andy Shevchenko , agk@redhat.com, Mike Snitzer , device-mapper development , shli@kernel.org, linux-raid@vger.kernel.org, "linux-input@vger.kernel.org" , Yury Norov , lkml , Mika Westerberg , Joe Perches List-Id: linux-raid.ids On Thu, Jun 21, 2018 at 05:13:39AM +0300, Andy Shevchenko wrote: > On Tue, Jun 19, 2018 at 2:10 AM, Andrew Morton > wrote: > > On Mon, 18 Jun 2018 15:01:43 -0700 Dmitry Torokhov wrote: > > >> We can't as we end up including bitmap.h (by the way of cpumask.h) > >> form slab.h, so we gen circular dependency. > > > > It's not just so easy. See below. > > > That info should have been in the changelog, and probably a code > > comment. > > > >> Maybe if we removed memcg > >> stuff from slab.h so we do not need to include workqueue.h... > > > > Or move the basic slab API stuff out of slab.h into a new header. Or > > create a new, standalone work_struct.h - that looks pretty simple. > > I tried to move out work_struct, it didn't help. There are actually > several circular dependencies that ends in bitmap.h either way or > another. > > First one is > > slab.h -> gfp.h -> mmzone.h -> nodemask.h -> bitmap.h > > And so on... > > Splitting out kXalloc stuff to a separate header won't help, I think, > because of the above. > Splitting out struct work_struct is just a tip of an iceberg. > Splitting out memcg stuff won't help in the similar way. > > I'm all ears for (a better) solution. I think ultimately we'd want to untangle this, but allocating bitmaps is not in any hot paths so having them as non-inlined functions should not hurt us that much for time being. Just my 2 cents... -- Dmitry