From: Will Deacon will.deacon@arm.com
commit 5ef3fe4cecdf82fdd71ce78988403963d01444d4 upstream.
Our atomic instructions (either LSE atomics of LDXR/STXR sequences) natively support byte, half-word, word and double-word memory accesses so there is no need to mask the data register prior to being stored.
Signed-off-by: Will Deacon will.deacon@arm.com [bwh: Backported to 4.19: adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/include/asm/atomic_ll_sc.h | 53 +++++++-------- arch/arm64/include/asm/atomic_lse.h | 46 ++++++------- arch/arm64/include/asm/cmpxchg.h | 116 +++++++++++++++++----------------- 3 files changed, 108 insertions(+), 107 deletions(-)
--- a/arch/arm64/include/asm/atomic_ll_sc.h +++ b/arch/arm64/include/asm/atomic_ll_sc.h @@ -248,48 +248,49 @@ __LL_SC_PREFIX(atomic64_dec_if_positive( } __LL_SC_EXPORT(atomic64_dec_if_positive);
-#define __CMPXCHG_CASE(w, sz, name, mb, acq, rel, cl) \ -__LL_SC_INLINE unsigned long \ -__LL_SC_PREFIX(__cmpxchg_case_##name(volatile void *ptr, \ - unsigned long old, \ - unsigned long new)) \ +#define __CMPXCHG_CASE(w, sfx, name, sz, mb, acq, rel, cl) \ +__LL_SC_INLINE u##sz \ +__LL_SC_PREFIX(__cmpxchg_case_##name##sz(volatile void *ptr, \ + unsigned long old, \ + u##sz new)) \ { \ - unsigned long tmp, oldval; \ + unsigned long tmp; \ + u##sz oldval; \ \ asm volatile( \ " prfm pstl1strm, %[v]\n" \ - "1: ld" #acq "xr" #sz "\t%" #w "[oldval], %[v]\n" \ + "1: ld" #acq "xr" #sfx "\t%" #w "[oldval], %[v]\n" \ " eor %" #w "[tmp], %" #w "[oldval], %" #w "[old]\n" \ " cbnz %" #w "[tmp], 2f\n" \ - " st" #rel "xr" #sz "\t%w[tmp], %" #w "[new], %[v]\n" \ + " st" #rel "xr" #sfx "\t%w[tmp], %" #w "[new], %[v]\n" \ " cbnz %w[tmp], 1b\n" \ " " #mb "\n" \ "2:" \ : [tmp] "=&r" (tmp), [oldval] "=&r" (oldval), \ - [v] "+Q" (*(unsigned long *)ptr) \ + [v] "+Q" (*(u##sz *)ptr) \ : [old] "Lr" (old), [new] "r" (new) \ : cl); \ \ return oldval; \ } \ -__LL_SC_EXPORT(__cmpxchg_case_##name); +__LL_SC_EXPORT(__cmpxchg_case_##name##sz);
-__CMPXCHG_CASE(w, b, 1, , , , ) -__CMPXCHG_CASE(w, h, 2, , , , ) -__CMPXCHG_CASE(w, , 4, , , , ) -__CMPXCHG_CASE( , , 8, , , , ) -__CMPXCHG_CASE(w, b, acq_1, , a, , "memory") -__CMPXCHG_CASE(w, h, acq_2, , a, , "memory") -__CMPXCHG_CASE(w, , acq_4, , a, , "memory") -__CMPXCHG_CASE( , , acq_8, , a, , "memory") -__CMPXCHG_CASE(w, b, rel_1, , , l, "memory") -__CMPXCHG_CASE(w, h, rel_2, , , l, "memory") -__CMPXCHG_CASE(w, , rel_4, , , l, "memory") -__CMPXCHG_CASE( , , rel_8, , , l, "memory") -__CMPXCHG_CASE(w, b, mb_1, dmb ish, , l, "memory") -__CMPXCHG_CASE(w, h, mb_2, dmb ish, , l, "memory") -__CMPXCHG_CASE(w, , mb_4, dmb ish, , l, "memory") -__CMPXCHG_CASE( , , mb_8, dmb ish, , l, "memory") +__CMPXCHG_CASE(w, b, , 8, , , , ) +__CMPXCHG_CASE(w, h, , 16, , , , ) +__CMPXCHG_CASE(w, , , 32, , , , ) +__CMPXCHG_CASE( , , , 64, , , , ) +__CMPXCHG_CASE(w, b, acq_, 8, , a, , "memory") +__CMPXCHG_CASE(w, h, acq_, 16, , a, , "memory") +__CMPXCHG_CASE(w, , acq_, 32, , a, , "memory") +__CMPXCHG_CASE( , , acq_, 64, , a, , "memory") +__CMPXCHG_CASE(w, b, rel_, 8, , , l, "memory") +__CMPXCHG_CASE(w, h, rel_, 16, , , l, "memory") +__CMPXCHG_CASE(w, , rel_, 32, , , l, "memory") +__CMPXCHG_CASE( , , rel_, 64, , , l, "memory") +__CMPXCHG_CASE(w, b, mb_, 8, dmb ish, , l, "memory") +__CMPXCHG_CASE(w, h, mb_, 16, dmb ish, , l, "memory") +__CMPXCHG_CASE(w, , mb_, 32, dmb ish, , l, "memory") +__CMPXCHG_CASE( , , mb_, 64, dmb ish, , l, "memory")
#undef __CMPXCHG_CASE
--- a/arch/arm64/include/asm/atomic_lse.h +++ b/arch/arm64/include/asm/atomic_lse.h @@ -480,24 +480,24 @@ static inline long atomic64_dec_if_posit
#define __LL_SC_CMPXCHG(op) __LL_SC_CALL(__cmpxchg_case_##op)
-#define __CMPXCHG_CASE(w, sz, name, mb, cl...) \ -static inline unsigned long __cmpxchg_case_##name(volatile void *ptr, \ - unsigned long old, \ - unsigned long new) \ +#define __CMPXCHG_CASE(w, sfx, name, sz, mb, cl...) \ +static inline u##sz __cmpxchg_case_##name##sz(volatile void *ptr, \ + unsigned long old, \ + u##sz new) \ { \ register unsigned long x0 asm ("x0") = (unsigned long)ptr; \ register unsigned long x1 asm ("x1") = old; \ - register unsigned long x2 asm ("x2") = new; \ + register u##sz x2 asm ("x2") = new; \ \ asm volatile( \ __LSE_PREAMBLE \ ARM64_LSE_ATOMIC_INSN( \ /* LL/SC */ \ - __LL_SC_CMPXCHG(name) \ + __LL_SC_CMPXCHG(name##sz) \ __nops(2), \ /* LSE atomics */ \ " mov " #w "30, %" #w "[old]\n" \ - " cas" #mb #sz "\t" #w "30, %" #w "[new], %[v]\n" \ + " cas" #mb #sfx "\t" #w "30, %" #w "[new], %[v]\n" \ " mov %" #w "[ret], " #w "30") \ : [ret] "+r" (x0), [v] "+Q" (*(unsigned long *)ptr) \ : [old] "r" (x1), [new] "r" (x2) \ @@ -506,22 +506,22 @@ static inline unsigned long __cmpxchg_ca return x0; \ }
-__CMPXCHG_CASE(w, b, 1, ) -__CMPXCHG_CASE(w, h, 2, ) -__CMPXCHG_CASE(w, , 4, ) -__CMPXCHG_CASE(x, , 8, ) -__CMPXCHG_CASE(w, b, acq_1, a, "memory") -__CMPXCHG_CASE(w, h, acq_2, a, "memory") -__CMPXCHG_CASE(w, , acq_4, a, "memory") -__CMPXCHG_CASE(x, , acq_8, a, "memory") -__CMPXCHG_CASE(w, b, rel_1, l, "memory") -__CMPXCHG_CASE(w, h, rel_2, l, "memory") -__CMPXCHG_CASE(w, , rel_4, l, "memory") -__CMPXCHG_CASE(x, , rel_8, l, "memory") -__CMPXCHG_CASE(w, b, mb_1, al, "memory") -__CMPXCHG_CASE(w, h, mb_2, al, "memory") -__CMPXCHG_CASE(w, , mb_4, al, "memory") -__CMPXCHG_CASE(x, , mb_8, al, "memory") +__CMPXCHG_CASE(w, b, , 8, ) +__CMPXCHG_CASE(w, h, , 16, ) +__CMPXCHG_CASE(w, , , 32, ) +__CMPXCHG_CASE(x, , , 64, ) +__CMPXCHG_CASE(w, b, acq_, 8, a, "memory") +__CMPXCHG_CASE(w, h, acq_, 16, a, "memory") +__CMPXCHG_CASE(w, , acq_, 32, a, "memory") +__CMPXCHG_CASE(x, , acq_, 64, a, "memory") +__CMPXCHG_CASE(w, b, rel_, 8, l, "memory") +__CMPXCHG_CASE(w, h, rel_, 16, l, "memory") +__CMPXCHG_CASE(w, , rel_, 32, l, "memory") +__CMPXCHG_CASE(x, , rel_, 64, l, "memory") +__CMPXCHG_CASE(w, b, mb_, 8, al, "memory") +__CMPXCHG_CASE(w, h, mb_, 16, al, "memory") +__CMPXCHG_CASE(w, , mb_, 32, al, "memory") +__CMPXCHG_CASE(x, , mb_, 64, al, "memory")
#undef __LL_SC_CMPXCHG #undef __CMPXCHG_CASE --- a/arch/arm64/include/asm/cmpxchg.h +++ b/arch/arm64/include/asm/cmpxchg.h @@ -30,46 +30,46 @@ * barrier case is generated as release+dmb for the former and * acquire+release for the latter. */ -#define __XCHG_CASE(w, sz, name, mb, nop_lse, acq, acq_lse, rel, cl) \ -static inline unsigned long __xchg_case_##name(unsigned long x, \ - volatile void *ptr) \ -{ \ - unsigned long ret, tmp; \ - \ - asm volatile(ARM64_LSE_ATOMIC_INSN( \ - /* LL/SC */ \ - " prfm pstl1strm, %2\n" \ - "1: ld" #acq "xr" #sz "\t%" #w "0, %2\n" \ - " st" #rel "xr" #sz "\t%w1, %" #w "3, %2\n" \ - " cbnz %w1, 1b\n" \ - " " #mb, \ - /* LSE atomics */ \ - " swp" #acq_lse #rel #sz "\t%" #w "3, %" #w "0, %2\n" \ - __nops(3) \ - " " #nop_lse) \ - : "=&r" (ret), "=&r" (tmp), "+Q" (*(unsigned long *)ptr) \ - : "r" (x) \ - : cl); \ - \ - return ret; \ +#define __XCHG_CASE(w, sfx, name, sz, mb, nop_lse, acq, acq_lse, rel, cl) \ +static inline u##sz __xchg_case_##name##sz(u##sz x, volatile void *ptr) \ +{ \ + u##sz ret; \ + unsigned long tmp; \ + \ + asm volatile(ARM64_LSE_ATOMIC_INSN( \ + /* LL/SC */ \ + " prfm pstl1strm, %2\n" \ + "1: ld" #acq "xr" #sfx "\t%" #w "0, %2\n" \ + " st" #rel "xr" #sfx "\t%w1, %" #w "3, %2\n" \ + " cbnz %w1, 1b\n" \ + " " #mb, \ + /* LSE atomics */ \ + " swp" #acq_lse #rel #sfx "\t%" #w "3, %" #w "0, %2\n" \ + __nops(3) \ + " " #nop_lse) \ + : "=&r" (ret), "=&r" (tmp), "+Q" (*(u##sz *)ptr) \ + : "r" (x) \ + : cl); \ + \ + return ret; \ }
-__XCHG_CASE(w, b, 1, , , , , , ) -__XCHG_CASE(w, h, 2, , , , , , ) -__XCHG_CASE(w, , 4, , , , , , ) -__XCHG_CASE( , , 8, , , , , , ) -__XCHG_CASE(w, b, acq_1, , , a, a, , "memory") -__XCHG_CASE(w, h, acq_2, , , a, a, , "memory") -__XCHG_CASE(w, , acq_4, , , a, a, , "memory") -__XCHG_CASE( , , acq_8, , , a, a, , "memory") -__XCHG_CASE(w, b, rel_1, , , , , l, "memory") -__XCHG_CASE(w, h, rel_2, , , , , l, "memory") -__XCHG_CASE(w, , rel_4, , , , , l, "memory") -__XCHG_CASE( , , rel_8, , , , , l, "memory") -__XCHG_CASE(w, b, mb_1, dmb ish, nop, , a, l, "memory") -__XCHG_CASE(w, h, mb_2, dmb ish, nop, , a, l, "memory") -__XCHG_CASE(w, , mb_4, dmb ish, nop, , a, l, "memory") -__XCHG_CASE( , , mb_8, dmb ish, nop, , a, l, "memory") +__XCHG_CASE(w, b, , 8, , , , , , ) +__XCHG_CASE(w, h, , 16, , , , , , ) +__XCHG_CASE(w, , , 32, , , , , , ) +__XCHG_CASE( , , , 64, , , , , , ) +__XCHG_CASE(w, b, acq_, 8, , , a, a, , "memory") +__XCHG_CASE(w, h, acq_, 16, , , a, a, , "memory") +__XCHG_CASE(w, , acq_, 32, , , a, a, , "memory") +__XCHG_CASE( , , acq_, 64, , , a, a, , "memory") +__XCHG_CASE(w, b, rel_, 8, , , , , l, "memory") +__XCHG_CASE(w, h, rel_, 16, , , , , l, "memory") +__XCHG_CASE(w, , rel_, 32, , , , , l, "memory") +__XCHG_CASE( , , rel_, 64, , , , , l, "memory") +__XCHG_CASE(w, b, mb_, 8, dmb ish, nop, , a, l, "memory") +__XCHG_CASE(w, h, mb_, 16, dmb ish, nop, , a, l, "memory") +__XCHG_CASE(w, , mb_, 32, dmb ish, nop, , a, l, "memory") +__XCHG_CASE( , , mb_, 64, dmb ish, nop, , a, l, "memory")
#undef __XCHG_CASE
@@ -80,13 +80,13 @@ static __always_inline unsigned long __ { \ switch (size) { \ case 1: \ - return __xchg_case##sfx##_1(x, ptr); \ + return __xchg_case##sfx##_8(x, ptr); \ case 2: \ - return __xchg_case##sfx##_2(x, ptr); \ + return __xchg_case##sfx##_16(x, ptr); \ case 4: \ - return __xchg_case##sfx##_4(x, ptr); \ + return __xchg_case##sfx##_32(x, ptr); \ case 8: \ - return __xchg_case##sfx##_8(x, ptr); \ + return __xchg_case##sfx##_64(x, ptr); \ default: \ BUILD_BUG(); \ } \ @@ -123,13 +123,13 @@ static __always_inline unsigned long __c { \ switch (size) { \ case 1: \ - return __cmpxchg_case##sfx##_1(ptr, (u8)old, new); \ + return __cmpxchg_case##sfx##_8(ptr, (u8)old, new); \ case 2: \ - return __cmpxchg_case##sfx##_2(ptr, (u16)old, new); \ + return __cmpxchg_case##sfx##_16(ptr, (u16)old, new); \ case 4: \ - return __cmpxchg_case##sfx##_4(ptr, old, new); \ + return __cmpxchg_case##sfx##_32(ptr, old, new); \ case 8: \ - return __cmpxchg_case##sfx##_8(ptr, old, new); \ + return __cmpxchg_case##sfx##_64(ptr, old, new); \ default: \ BUILD_BUG(); \ } \ @@ -197,16 +197,16 @@ __CMPXCHG_GEN(_mb) __ret; \ })
-#define __CMPWAIT_CASE(w, sz, name) \ -static inline void __cmpwait_case_##name(volatile void *ptr, \ - unsigned long val) \ +#define __CMPWAIT_CASE(w, sfx, sz) \ +static inline void __cmpwait_case_##sz(volatile void *ptr, \ + unsigned long val) \ { \ unsigned long tmp; \ \ asm volatile( \ " sevl\n" \ " wfe\n" \ - " ldxr" #sz "\t%" #w "[tmp], %[v]\n" \ + " ldxr" #sfx "\t%" #w "[tmp], %[v]\n" \ " eor %" #w "[tmp], %" #w "[tmp], %" #w "[val]\n" \ " cbnz %" #w "[tmp], 1f\n" \ " wfe\n" \ @@ -215,10 +215,10 @@ static inline void __cmpwait_case_##name : [val] "r" (val)); \ }
-__CMPWAIT_CASE(w, b, 1); -__CMPWAIT_CASE(w, h, 2); -__CMPWAIT_CASE(w, , 4); -__CMPWAIT_CASE( , , 8); +__CMPWAIT_CASE(w, b, 8); +__CMPWAIT_CASE(w, h, 16); +__CMPWAIT_CASE(w, , 32); +__CMPWAIT_CASE( , , 64);
#undef __CMPWAIT_CASE
@@ -229,13 +229,13 @@ static __always_inline void __cmpwait##s { \ switch (size) { \ case 1: \ - return __cmpwait_case##sfx##_1(ptr, (u8)val); \ + return __cmpwait_case##sfx##_8(ptr, (u8)val); \ case 2: \ - return __cmpwait_case##sfx##_2(ptr, (u16)val); \ + return __cmpwait_case##sfx##_16(ptr, (u16)val); \ case 4: \ - return __cmpwait_case##sfx##_4(ptr, val); \ + return __cmpwait_case##sfx##_32(ptr, val); \ case 8: \ - return __cmpwait_case##sfx##_8(ptr, val); \ + return __cmpwait_case##sfx##_64(ptr, val); \ default: \ BUILD_BUG(); \ } \