From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752593AbdGEX5r (ORCPT ); Wed, 5 Jul 2017 19:57:47 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:53082 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752092AbdGEX5p (ORCPT ); Wed, 5 Jul 2017 19:57:45 -0400 Date: Wed, 5 Jul 2017 16:57:38 -0700 From: "Paul E. McKenney" To: Boqun Feng Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, parri.andrea@gmail.com, dave@stgolabs.net, manfred@colorfullife.com, arnd@arndb.de, peterz@infradead.org, netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, will.deacon@arm.com, oleg@redhat.com, mingo@redhat.com, netfilter-devel@vger.kernel.org, tj@kernel.org, stern@rowland.harvard.edu, akpm@linux-foundation.org, torvalds@linux-foundation.org, Paul Mackerras Subject: Re: [PATCH RFC 21/26] powerpc: Remove spin_unlock_wait() arch-specific definitions Reply-To: paulmck@linux.vnet.ibm.com References: <20170629235918.GA6445@linux.vnet.ibm.com> <1498780894-8253-21-git-send-email-paulmck@linux.vnet.ibm.com> <20170702035807.tnzmkynyevfobt5a@tardis> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170702035807.tnzmkynyevfobt5a@tardis> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 17070523-0036-0000-0000-00000240C59A X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007326; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000214; SDB=6.00883409; UDB=6.00440702; IPR=6.00663601; BA=6.00005454; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00016100; XFM=3.00000015; UTC=2017-07-05 23:57:41 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17070523-0037-0000-0000-000040FC99BF Message-Id: <20170705235738.GK2393@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-07-05_17:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1707050390 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 02, 2017 at 11:58:07AM +0800, Boqun Feng wrote: > On Thu, Jun 29, 2017 at 05:01:29PM -0700, Paul E. McKenney wrote: > > There is no agreed-upon definition of spin_unlock_wait()'s semantics, > > and it appears that all callers could do just as well with a lock/unlock > > pair. This commit therefore removes the underlying arch-specific > > arch_spin_unlock_wait(). > > > > Signed-off-by: Paul E. McKenney > > Cc: Benjamin Herrenschmidt > > Cc: Paul Mackerras > > Cc: Michael Ellerman > > Cc: > > Cc: Will Deacon > > Cc: Peter Zijlstra > > Cc: Alan Stern > > Cc: Andrea Parri > > Cc: Linus Torvalds > > Acked-by: Boqun Feng And finally applied in preparation for v2 of the patch series. Thank you!!! Thanx, Paul > Regards, > Boqun > > > --- > > arch/powerpc/include/asm/spinlock.h | 33 --------------------------------- > > 1 file changed, 33 deletions(-) > > > > diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h > > index 8c1b913de6d7..d256e448ea49 100644 > > --- a/arch/powerpc/include/asm/spinlock.h > > +++ b/arch/powerpc/include/asm/spinlock.h > > @@ -170,39 +170,6 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock) > > lock->slock = 0; > > } > > > > -static inline void arch_spin_unlock_wait(arch_spinlock_t *lock) > > -{ > > - arch_spinlock_t lock_val; > > - > > - smp_mb(); > > - > > - /* > > - * Atomically load and store back the lock value (unchanged). This > > - * ensures that our observation of the lock value is ordered with > > - * respect to other lock operations. > > - */ > > - __asm__ __volatile__( > > -"1: " PPC_LWARX(%0, 0, %2, 0) "\n" > > -" stwcx. %0, 0, %2\n" > > -" bne- 1b\n" > > - : "=&r" (lock_val), "+m" (*lock) > > - : "r" (lock) > > - : "cr0", "xer"); > > - > > - if (arch_spin_value_unlocked(lock_val)) > > - goto out; > > - > > - while (lock->slock) { > > - HMT_low(); > > - if (SHARED_PROCESSOR) > > - __spin_yield(lock); > > - } > > - HMT_medium(); > > - > > -out: > > - smp_mb(); > > -} > > - > > /* > > * Read-write spinlocks, allowing multiple readers > > * but only one writer. > > -- > > 2.5.2 > >