From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Tue, 27 Feb 2018 17:33:23 +0000 Subject: [RFC PATCH v2 08/12] arm64: cmpxchg: Include build_bug.h instead of bug.h for BUILD_BUG In-Reply-To: <20180226154848.ejqxw5lkbiqqxlsf@salmiak> References: <1519657500-15094-1-git-send-email-will.deacon@arm.com> <1519657500-15094-9-git-send-email-will.deacon@arm.com> <20180226154848.ejqxw5lkbiqqxlsf@salmiak> Message-ID: <20180227173322.GK29123@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Feb 26, 2018 at 03:48:49PM +0000, Mark Rutland wrote: > On Mon, Feb 26, 2018 at 03:04:56PM +0000, Will Deacon wrote: > > Having asm/cmpxchg.h pull in linux/bug.h is problematic because this > > ends up pulling in the atomic bitops which themselves may be built on > > top of atomic.h and cmpxchg.h. > > > > Instead, just include build_bug.h for the definition of BUILD_BUG. > > We also use VM_BUG_ON(), defined in , which includes > . > > ... so I think we still have some fragility here, albeit no worse than before. > > We also miss includes for: > > * (raw_cpu_ptr) > * (preempt_disable, preempt_enable) Hmm, we can't include this one because it pulls in linux/bitops.h. I've moved the percpu cmpxchg stuff into asm/percpu.h, but that too is missing the linux/preempt.h #include, so I've added that as well. Generally, I think if we want to clean up our #includes then that's better done as a separate series rather than as a piecemeal effort, which will likely fail to identify many of the underlying problems. Will