eal/ppc: replace rte_atomicXX ops with C11 atomic builtins
PATCH 1/1 eal/ppc: replace rte_atomicXX ops with C11 atomic builtins
Replace existing PPC assembly code for rte_atomicXX ops with compiler atomic builtins as prevously adopted by DPDK (see [1] and [2]). This has the additional benefit of resolving a POWER10 build failure due to an outstanding gcc issue which fails on the existing PPC assembly code [3].
[1] https://www.dpdk.org/blog/2021/03/26/dpdk-adopts-the-c11-memory-model/
[2] https://doc.dpdk.org/guides/rel_notes/deprecation.html
[3] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98519
--- lib/eal/ppc/include/rte_atomic.h | 231 +++---------------------------- 1 file changed, 21 insertions(+), 210 deletions(-)
lib/eal/ppc/include/rte_atomic.h +21 -210
@@ -1,6 +1,7 @@/* * SPDX-License-Identifier: BSD-3-Clause * Inspired from FreeBSD src/sys/powerpc/include/atomic.h +* Copyright (c) 2021 IBM Corporation * Copyright (c) 2008 Marcel Moolenaar * Copyright (c) 2001 Benno Rice * Copyright (c) 2001 David E. O'Brien
@@ -16,6 +17,7 @@ extern "C" {#endif #include <stdint.h> +#include <rte_compat.h> #include "generic/rte_atomic.h" #define rte_mb () asm volatile("sync" : : : "memory")
@@ -43,9 +45,6 @@ rte_atomic_thread_fence(int memorder) }/*------------------------- 16 bit atomic operations -------------------------*/ -/* To be compatible with Power7, use GCC built-in functions for 16 bit -* operations */ -#ifndef RTE_FORCE_INTRINSICS static inline int rte_atomic16_cmpset (volatile uint16_t *dst,uint16_t exp,uint16_t src)
@@ -92,30 +91,8 @@ rte_atomic16_exchange(volatile uint16_t *dst, uint16_t val)static inline int rte_atomic32_cmpset (volatile uint32_t *dst,uint32_t exp,uint32_t src) { -unsigned int ret =0 ; - - asmvolatile ( -"\tlwsync\n" -"1:\tlwarx %[ret], 0, %[dst]\n" -"cmplw %[exp], %[ret]\n" -"bne 2f\n" -"stwcx. %[src], 0, %[dst]\n" -"bne- 1b\n" -"li %[ret], 1\n" -"b 3f\n" -"2:\n" -"stwcx. %[ret], 0, %[dst]\n" -"li %[ret], 0\n" -"3:\n" -"isync\n" - : [ret]"=&r" (ret),"=m" (*dst) - : [dst]"r" (dst), - [exp]"r" (exp), - [src]"r" (src), -"m" (*dst) - :"cc" ,"memory" ); - -return ret; +return __atomic_compare_exchange (dst, &exp, &src,0 , __ATOMIC_ACQUIRE, + __ATOMIC_ACQUIRE) ?1 :0 ; }static inline int rte_atomic32_test_and_set (rte_atomic32_t *v)
@@ -126,67 +103,23 @@ static inline int rte_atomic32_test_and_set(rte_atomic32_t *v)static inline void rte_atomic32_inc (rte_atomic32_t *v) { -int t; - - asmvolatile ( -"1: lwarx %[t],0,%[cnt]\n" -"addic %[t],%[t],1\n" -"stwcx. %[t],0,%[cnt]\n" -"bne- 1b\n" - : [t]"=&r" (t),"=m" (v->cnt) - : [cnt]"r" (&v->cnt),"m" (v->cnt) - :"cc" ,"xer" ,"memory" ); +__atomic_add_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE); }static inline void rte_atomic32_dec (rte_atomic32_t *v) { -int t; - - asmvolatile ( -"1: lwarx %[t],0,%[cnt]\n" -"addic %[t],%[t],-1\n" -"stwcx. %[t],0,%[cnt]\n" -"bne- 1b\n" - : [t]"=&r" (t),"=m" (v->cnt) - : [cnt]"r" (&v->cnt),"m" (v->cnt) - :"cc" ,"xer" ,"memory" ); +__atomic_sub_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE); }static inline int rte_atomic32_inc_and_test (rte_atomic32_t *v) { -int ret; - - asmvolatile ( -"\n\tlwsync\n" -"1: lwarx %[ret],0,%[cnt]\n" -"addic %[ret],%[ret],1\n" -"stwcx. %[ret],0,%[cnt]\n" -"bne- 1b\n" -"isync\n" - : [ret]"=&r" (ret) - : [cnt]"r" (&v->cnt) - :"cc" ,"xer" ,"memory" ); - -return ret ==0 ; +return __atomic_add_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE) ==0 ; }static inline int rte_atomic32_dec_and_test (rte_atomic32_t *v) { -int ret; - - asmvolatile ( -"\n\tlwsync\n" -"1: lwarx %[ret],0,%[cnt]\n" -"addic %[ret],%[ret],-1\n" -"stwcx. %[ret],0,%[cnt]\n" -"bne- 1b\n" -"isync\n" - : [ret]"=&r" (ret) - : [cnt]"r" (&v->cnt) - :"cc" ,"xer" ,"memory" ); - -return ret ==0 ; +return __atomic_sub_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE) ==0 ; } static inline uint32_t
@@ -200,29 +133,8 @@ rte_atomic32_exchange(volatile uint32_t *dst, uint32_t val)static inline int rte_atomic64_cmpset (volatile uint64_t *dst,uint64_t exp,uint64_t src) { -unsigned int ret =0 ; - - asmvolatile ( -"\tlwsync\n" -"1: ldarx %[ret], 0, %[dst]\n" -"cmpld %[exp], %[ret]\n" -"bne 2f\n" -"stdcx. %[src], 0, %[dst]\n" -"bne- 1b\n" -"li %[ret], 1\n" -"b 3f\n" -"2:\n" -"stdcx. %[ret], 0, %[dst]\n" -"li %[ret], 0\n" -"3:\n" -"isync\n" - : [ret]"=&r" (ret),"=m" (*dst) - : [dst]"r" (dst), - [exp]"r" (exp), - [src]"r" (src), -"m" (*dst) - :"cc" ,"memory" ); -return ret; +return __atomic_compare_exchange (dst, &exp, &src,0 , __ATOMIC_ACQUIRE, + __ATOMIC_ACQUIRE) ?1 :0 ; } static inline void
@@ -234,167 +146,66 @@ rte_atomic64_init(rte_atomic64_t *v)static inline int64_t rte_atomic64_read (rte_atomic64_t *v) { -long ret; - - asmvolatile ("ld%U1%X1 %[ret],%[cnt]" - : [ret]"=r" (ret) - : [cnt]"m" (v->cnt)); - -return ret; +return v->cnt; }static inline void rte_atomic64_set (rte_atomic64_t *v,int64_t new_value) { - asmvolatile ("std%U0%X0 %[new_value],%[cnt]" - : [cnt]"=m" (v->cnt) - : [new_value]"r" (new_value)); + v->cnt = new_value; }static inline void rte_atomic64_add (rte_atomic64_t *v,int64_t inc) { -long t; - - asmvolatile ( -"1: ldarx %[t],0,%[cnt]\n" -"add %[t],%[inc],%[t]\n" -"stdcx. %[t],0,%[cnt]\n" -"bne- 1b\n" - : [t]"=&r" (t),"=m" (v->cnt) - : [cnt]"r" (&v->cnt), [inc]"r" (inc),"m" (v->cnt) - :"cc" ,"memory" ); +__atomic_add_fetch (&v->cnt, inc, __ATOMIC_ACQUIRE); }static inline void rte_atomic64_sub (rte_atomic64_t *v,int64_t dec) { -long t; - - asmvolatile ( -"1: ldarx %[t],0,%[cnt]\n" -"subf %[t],%[dec],%[t]\n" -"stdcx. %[t],0,%[cnt]\n" -"bne- 1b\n" - : [t]"=&r" (t),"+m" (v->cnt) - : [cnt]"r" (&v->cnt), [dec]"r" (dec),"m" (v->cnt) - :"cc" ,"memory" ); +__atomic_sub_fetch (&v->cnt, dec, __ATOMIC_ACQUIRE); }static inline void rte_atomic64_inc (rte_atomic64_t *v) { -long t; - - asmvolatile ( -"1: ldarx %[t],0,%[cnt]\n" -"addic %[t],%[t],1\n" -"stdcx. %[t],0,%[cnt]\n" -"bne- 1b\n" - : [t]"=&r" (t),"+m" (v->cnt) - : [cnt]"r" (&v->cnt),"m" (v->cnt) - :"cc" ,"xer" ,"memory" ); +__atomic_add_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE); }static inline void rte_atomic64_dec (rte_atomic64_t *v) { -long t; - - asmvolatile ( -"1: ldarx %[t],0,%[cnt]\n" -"addic %[t],%[t],-1\n" -"stdcx. %[t],0,%[cnt]\n" -"bne- 1b\n" - : [t]"=&r" (t),"+m" (v->cnt) - : [cnt]"r" (&v->cnt),"m" (v->cnt) - :"cc" ,"xer" ,"memory" ); +__atomic_sub_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE); }static inline int64_t rte_atomic64_add_return (rte_atomic64_t *v,int64_t inc) { -long ret; - - asmvolatile ( -"\n\tlwsync\n" -"1: ldarx %[ret],0,%[cnt]\n" -"add %[ret],%[inc],%[ret]\n" -"stdcx. %[ret],0,%[cnt]\n" -"bne- 1b\n" -"isync\n" - : [ret]"=&r" (ret) - : [inc]"r" (inc), [cnt]"r" (&v->cnt) - :"cc" ,"memory" ); - -return ret; +return __atomic_add_fetch (&v->cnt, inc, __ATOMIC_ACQUIRE); }static inline int64_t rte_atomic64_sub_return (rte_atomic64_t *v,int64_t dec) { -long ret; - - asmvolatile ( -"\n\tlwsync\n" -"1: ldarx %[ret],0,%[cnt]\n" -"subf %[ret],%[dec],%[ret]\n" -"stdcx. %[ret],0,%[cnt]\n" -"bne- 1b\n" -"isync\n" - : [ret]"=&r" (ret) - : [dec]"r" (dec), [cnt]"r" (&v->cnt) - :"cc" ,"memory" ); - -return ret; +return __atomic_sub_fetch (&v->cnt, dec, __ATOMIC_ACQUIRE); }static inline int rte_atomic64_inc_and_test (rte_atomic64_t *v) { -long ret; - - asmvolatile ( -"\n\tlwsync\n" -"1: ldarx %[ret],0,%[cnt]\n" -"addic %[ret],%[ret],1\n" -"stdcx. %[ret],0,%[cnt]\n" -"bne- 1b\n" -"isync\n" - : [ret]"=&r" (ret) - : [cnt]"r" (&v->cnt) - :"cc" ,"xer" ,"memory" ); - -return ret ==0 ; +return __atomic_add_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE) ==0 ; }static inline int rte_atomic64_dec_and_test (rte_atomic64_t *v) { -long ret; - - asmvolatile ( -"\n\tlwsync\n" -"1: ldarx %[ret],0,%[cnt]\n" -"addic %[ret],%[ret],-1\n" -"stdcx. %[ret],0,%[cnt]\n" -"bne- 1b\n" -"isync\n" - : [ret]"=&r" (ret) - : [cnt]"r" (&v->cnt) - :"cc" ,"xer" ,"memory" ); - -return ret ==0 ; +return __atomic_sub_fetch (&v->cnt,1 , __ATOMIC_ACQUIRE) ==0 ; }static inline int rte_atomic64_test_and_set (rte_atomic64_t *v) {return rte_atomic64_cmpset ((volatile uint64_t *)&v->cnt,0 ,1 ); } -/** -* Atomically set a 64-bit counter to 0. -* -* @param v -* A pointer to the atomic counter. -*/ +static inline void rte_atomic64_clear (rte_atomic64_t *v) { v->cnt =0 ;
--
2.27.0
David Marchand
AppliedQuoted 3 lines · David Christensen
Replace existing PPC assembly code for
rte_atomicXXops with compiler atomic builtins as prevously adopted by DPDK (see [1] and [2]). This
previously*
Quoted 8 lines
has the additional benefit of resolving a POWER10 build failure due to an outstanding gcc issue which fails on the existing PPC assembly code [3].
[1] https://www.dpdk.org/blog/2021/03/26/dpdk-adopts-the-c11-memory-model/
[2] https://doc.dpdk.org/guides/rel_notes/deprecation.html
[3] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98519Signed-off-by David Christensen <[email protected]>
Applied, thanks.
Signature · 1 line
David Marchand