From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: [PATCH -v2 11/33] locking,hexagon: Implement atomic_fetch_{add,sub,and,or,xor}() Date: Tue, 31 May 2016 12:19:36 +0200 Message-ID: <20160531102642.152411631@infradead.org> References: <20160531101925.702692792@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: Content-Disposition: inline; filename=peterz-atomic-fetch-hexagon.patch Sender: linux-kernel-owner@vger.kernel.org To: torvalds@linux-foundation.org, mingo@kernel.org, tglx@linutronix.de, will.deacon@arm.com, paulmck@linux.vnet.ibm.com, boqun.feng@gmail.com, waiman.long@hpe.com, fweisbec@gmail.com Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, rth@twiddle.net, vgupta@synopsys.com, linux@arm.linux.org.uk, egtvedt@samfundet.no, realmz6@gmail.com, ysato@users.sourceforge.jp, rkuo@codeaurora.org, tony.luck@intel.com, geert@linux-m68k.org, james.hogan@imgtec.com, ralf@linux-mips.org, dhowells@redhat.com, jejb@parisc-linux.org, mpe@ellerman.id.au, schwidefsky@de.ibm.com, dalias@libc.org, davem@davemloft.net, cmetcalf@mellanox.com, jcmvbkbc@gmail.com, arnd@arndb.de, peterz@infradead.org, dbueso@suse.de, fengguang.wu@intel.com List-Id: linux-arch.vger.kernel.org Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) --- arch/hexagon/include/asm/atomic.h | 33 ++++++++++++++++++++++++++++----- 1 file changed, 28 insertions(+), 5 deletions(-) --- a/arch/hexagon/include/asm/atomic.h +++ b/arch/hexagon/include/asm/atomic.h @@ -110,7 +110,7 @@ static inline void atomic_##op(int i, at ); \ } \ -#define ATOMIC_OP_RETURN(op) \ +#define ATOMIC_OP_RETURN(op) \ static inline int atomic_##op##_return(int i, atomic_t *v) \ { \ int output; \ @@ -127,16 +127,39 @@ static inline int atomic_##op##_return(i return output; \ } -#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) +#define ATOMIC_FETCH_OP(op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + int output, val; \ + \ + __asm__ __volatile__ ( \ + "1: %0 = memw_locked(%2);\n" \ + " %1 = "#op "(%0,%3);\n" \ + " memw_locked(%2,P3)=%1;\n" \ + " if !P3 jump 1b;\n" \ + : "=&r" (output), "=&r" (val) \ + : "r" (&v->counter), "r" (i) \ + : "memory", "p3" \ + ); \ + return output; \ +} + +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op) ATOMIC_OPS(add) ATOMIC_OPS(sub) -ATOMIC_OP(and) -ATOMIC_OP(or) -ATOMIC_OP(xor) +#undef ATOMIC_OPS +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) + +#define atomic_fetch_or atomic_fetch_or + +ATOMIC_OPS(and) +ATOMIC_OPS(or) +ATOMIC_OPS(xor) #undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP_RETURN #undef ATOMIC_OP From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.9]:43374 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751680AbcEaK3v (ORCPT ); Tue, 31 May 2016 06:29:51 -0400 Message-ID: <20160531102642.152411631@infradead.org> Date: Tue, 31 May 2016 12:19:36 +0200 From: Peter Zijlstra Subject: [PATCH -v2 11/33] locking,hexagon: Implement atomic_fetch_{add,sub,and,or,xor}() References: <20160531101925.702692792@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline; filename=peterz-atomic-fetch-hexagon.patch Sender: linux-arch-owner@vger.kernel.org List-ID: To: torvalds@linux-foundation.org, mingo@kernel.org, tglx@linutronix.de, will.deacon@arm.com, paulmck@linux.vnet.ibm.com, boqun.feng@gmail.com, waiman.long@hpe.com, fweisbec@gmail.com Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, rth@twiddle.net, vgupta@synopsys.com, linux@arm.linux.org.uk, egtvedt@samfundet.no, realmz6@gmail.com, ysato@users.sourceforge.jp, rkuo@codeaurora.org, tony.luck@intel.com, geert@linux-m68k.org, james.hogan@imgtec.com, ralf@linux-mips.org, dhowells@redhat.com, jejb@parisc-linux.org, mpe@ellerman.id.au, schwidefsky@de.ibm.com, dalias@libc.org, davem@davemloft.net, cmetcalf@mellanox.com, jcmvbkbc@gmail.com, arnd@arndb.de, peterz@infradead.org, dbueso@suse.de, fengguang.wu@intel.com Message-ID: <20160531101936.4zivsG4HxPB01gmgt7llVdSW1c-_ejewXgB_QuPQY4I@z> Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) --- arch/hexagon/include/asm/atomic.h | 33 ++++++++++++++++++++++++++++----- 1 file changed, 28 insertions(+), 5 deletions(-) --- a/arch/hexagon/include/asm/atomic.h +++ b/arch/hexagon/include/asm/atomic.h @@ -110,7 +110,7 @@ static inline void atomic_##op(int i, at ); \ } \ -#define ATOMIC_OP_RETURN(op) \ +#define ATOMIC_OP_RETURN(op) \ static inline int atomic_##op##_return(int i, atomic_t *v) \ { \ int output; \ @@ -127,16 +127,39 @@ static inline int atomic_##op##_return(i return output; \ } -#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) +#define ATOMIC_FETCH_OP(op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + int output, val; \ + \ + __asm__ __volatile__ ( \ + "1: %0 = memw_locked(%2);\n" \ + " %1 = "#op "(%0,%3);\n" \ + " memw_locked(%2,P3)=%1;\n" \ + " if !P3 jump 1b;\n" \ + : "=&r" (output), "=&r" (val) \ + : "r" (&v->counter), "r" (i) \ + : "memory", "p3" \ + ); \ + return output; \ +} + +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op) ATOMIC_OPS(add) ATOMIC_OPS(sub) -ATOMIC_OP(and) -ATOMIC_OP(or) -ATOMIC_OP(xor) +#undef ATOMIC_OPS +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) + +#define atomic_fetch_or atomic_fetch_or + +ATOMIC_OPS(and) +ATOMIC_OPS(or) +ATOMIC_OPS(xor) #undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP_RETURN #undef ATOMIC_OP