The branch main has been updated by jhibbits: URL: https://cgit.FreeBSD.org/src/commit/?id=cd22fd0549c9a65b8806fd013f98be89c34c44f7
commit cd22fd0549c9a65b8806fd013f98be89c34c44f7 Author: Justin Hibbits <[email protected]> AuthorDate: 2025-09-22 14:35:59 +0000 Commit: Justin Hibbits <[email protected]> CommitDate: 2026-01-17 04:10:02 +0000 powerpc: Add ISA 2.06 sub-word atomic set/clear Add atomic_set/clear_short/char for doing 8-bit and 16-bit operations more efficiently on "newer" architectures (POWER7 and later). Piggybacks on b31abc95eb. --- sys/powerpc/include/atomic.h | 82 ++++++++++++++++++++++++++++++-------------- 1 file changed, 56 insertions(+), 26 deletions(-) diff --git a/sys/powerpc/include/atomic.h b/sys/powerpc/include/atomic.h index b2d7549e5bd0..60fb678e6b41 100644 --- a/sys/powerpc/include/atomic.h +++ b/sys/powerpc/include/atomic.h @@ -165,6 +165,28 @@ _ATOMIC_ADD(long) * { *p &= ~v; } */ +#ifdef ISA_206_ATOMICS +#define __atomic_clear_char(p, v, t) \ + __asm __volatile( \ + "1: lbarx %0, 0, %2\n" \ + " andc %0, %0, %3\n" \ + " stbcx. %0, 0, %2\n" \ + " bne- 1b\n" \ + : "=&r" (t), "=m" (*p) \ + : "r" (p), "r" (v), "m" (*p) \ + : "cr0", "memory") \ + /* __atomic_clear_short */ +#define __atomic_clear_short(p, v, t) \ + __asm __volatile( \ + "1: lharx %0, 0, %2\n" \ + " andc %0, %0, %3\n" \ + " sthcx. %0, 0, %2\n" \ + " bne- 1b\n" \ + : "=&r" (t), "=m" (*p) \ + : "r" (p), "r" (v), "m" (*p) \ + : "cr0", "memory") \ + /* __atomic_clear_short */ +#endif #define __atomic_clear_int(p, v, t) \ __asm __volatile( \ "1: lwarx %0, 0, %2\n" \ @@ -222,6 +244,11 @@ _ATOMIC_ADD(long) } \ /* _ATOMIC_CLEAR */ +#ifdef ISA_206_ATOMICS +_ATOMIC_CLEAR(char) +_ATOMIC_CLEAR(short) +#endif + _ATOMIC_CLEAR(int) _ATOMIC_CLEAR(long) @@ -265,6 +292,28 @@ _ATOMIC_CLEAR(long) * atomic_set(p, v) * { *p |= v; } */ +#ifdef ISA_206_ATOMICS +#define __atomic_set_char(p, v, t) \ + __asm __volatile( \ + "1: lbarx %0, 0, %2\n" \ + " or %0, %3, %0\n" \ + " stbcx. %0, 0, %2\n" \ + " bne- 1b\n" \ + : "=&r" (t), "=m" (*p) \ + : "r" (p), "r" (v), "m" (*p) \ + : "cr0", "memory") \ + /* __atomic_set_char */ +#define __atomic_set_short(p, v, t) \ + __asm __volatile( \ + "1: lharx %0, 0, %2\n" \ + " or %0, %3, %0\n" \ + " sthcx. %0, 0, %2\n" \ + " bne- 1b\n" \ + : "=&r" (t), "=m" (*p) \ + : "r" (p), "r" (v), "m" (*p) \ + : "cr0", "memory") \ + /* __atomic_set_short */ +#endif #define __atomic_set_int(p, v, t) \ __asm __volatile( \ @@ -323,6 +372,11 @@ _ATOMIC_CLEAR(long) } \ /* _ATOMIC_SET */ +#ifdef ISA_206_ATOMICS +_ATOMIC_SET(char) +_ATOMIC_SET(short) +#endif + _ATOMIC_SET(int) _ATOMIC_SET(long) @@ -1140,34 +1194,10 @@ atomic_thread_fence_seq_cst(void) #define atomic_set_short atomic_set_16 #define atomic_clear_short atomic_clear_16 #else - -static __inline void -atomic_set_short(volatile u_short *p, u_short bit) -{ - u_short v; - - v = atomic_load_short(p); - for (;;) { - if (atomic_fcmpset_16(p, &v, v | bit)) - break; - } -} - -static __inline void -atomic_clear_short(volatile u_short *p, u_short bit) -{ - u_short v; - - v = atomic_load_short(p); - for (;;) { - if (atomic_fcmpset_16(p, &v, v & ~bit)) - break; - } -} - +#define atomic_set_8 atomic_set_char +#define atomic_clear_8 atomic_clear_char #define atomic_set_16 atomic_set_short #define atomic_clear_16 atomic_clear_short - #endif /* ISA_206_ATOMICS */ /* These need sys/_atomic_subword.h on non-ISA-2.06-atomic platforms. */
