From: Peter Zijlstra <peterz@infradead.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
Subject: [PATCH -v2 02/33] locking,arc: Implement atomic_fetch_{add,sub,and,andnot,or,xor}()
Date: Tue, 31 May 2016 12:19:27 +0200 [thread overview]
Message-ID: <20160531102641.582308264@infradead.org> (raw)
In-Reply-To: 20160531101925.702692792@infradead.org
[-- Attachment #1: peterz-atomic-fetch-arc.patch --]
[-- Type: text/plain, Size: 4617 bytes --]
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).
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/arc/include/asm/atomic.h | 103 ++++++++++++++++++++++++++++++++++++++----
1 file changed, 94 insertions(+), 9 deletions(-)
--- a/arch/arc/include/asm/atomic.h
+++ b/arch/arc/include/asm/atomic.h
@@ -104,6 +104,37 @@ static inline int atomic_##op##_return(i
return val; \
}
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ unsigned int val, orig; \
+ SCOND_FAIL_RETRY_VAR_DEF \
+ \
+ /* \
+ * Explicit full memory barrier needed before/after as \
+ * LLOCK/SCOND thmeselves don't provide any such semantics \
+ */ \
+ smp_mb(); \
+ \
+ __asm__ __volatile__( \
+ "1: llock %[orig], [%[ctr]] \n" \
+ " " #asm_op " %[val], %[orig], %[i] \n" \
+ " scond %[val], [%[ctr]] \n" \
+ " \n" \
+ SCOND_FAIL_RETRY_ASM \
+ \
+ : [val] "=&r" (val), \
+ [orig] "=&r" (orig) \
+ SCOND_FAIL_RETRY_VARS \
+ : [ctr] "r" (&v->counter), \
+ [i] "ir" (i) \
+ : "cc"); \
+ \
+ smp_mb(); \
+ \
+ return orig; \
+}
+
#else /* !CONFIG_ARC_HAS_LLSC */
#ifndef CONFIG_SMP
@@ -166,21 +197,46 @@ static inline int atomic_##op##_return(i
return temp; \
}
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ unsigned long flags; \
+ unsigned long orig; \
+ \
+ /* \
+ * spin lock/unlock provides the needed smp_mb() before/after \
+ */ \
+ atomic_ops_lock(flags); \
+ orig = v->counter; \
+ v->counter c_op i; \
+ atomic_ops_unlock(flags); \
+ \
+ return orig; \
+}
+
#endif /* !CONFIG_ARC_HAS_LLSC */
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
- ATOMIC_OP_RETURN(op, c_op, asm_op)
+ ATOMIC_OP_RETURN(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)
#define atomic_andnot atomic_andnot
-ATOMIC_OP(and, &=, and)
-ATOMIC_OP(andnot, &= ~, bic)
-ATOMIC_OP(or, |=, or)
-ATOMIC_OP(xor, ^=, xor)
+#define atomic_fetch_or atomic_fetch_or
+
+#undef ATOMIC_OPS
+#define ATOMIC_OPS(op, c_op, asm_op) \
+ ATOMIC_OP(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(and, &=, and)
+ATOMIC_OPS(andnot, &= ~, bic)
+ATOMIC_OPS(or, |=, or)
+ATOMIC_OPS(xor, ^=, xor)
#undef SCOND_FAIL_RETRY_VAR_DEF
#undef SCOND_FAIL_RETRY_ASM
@@ -245,22 +301,51 @@ static inline int atomic_##op##_return(i
return temp; \
}
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ unsigned int temp = i; \
+ \
+ /* Explicit full memory barrier needed before/after */ \
+ smp_mb(); \
+ \
+ __asm__ __volatile__( \
+ " mov r2, %0\n" \
+ " mov r3, %1\n" \
+ " .word %2\n" \
+ " mov %0, r2" \
+ : "+r"(temp) \
+ : "r"(&v->counter), "i"(asm_op) \
+ : "r2", "r3", "memory"); \
+ \
+ smp_mb(); \
+ \
+ return temp; \
+}
+
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
- ATOMIC_OP_RETURN(op, c_op, asm_op)
+ ATOMIC_OP_RETURN(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, CTOP_INST_AADD_DI_R2_R2_R3)
#define atomic_sub(i, v) atomic_add(-(i), (v))
#define atomic_sub_return(i, v) atomic_add_return(-(i), (v))
-ATOMIC_OP(and, &=, CTOP_INST_AAND_DI_R2_R2_R3)
+#undef ATOMIC_OPS
+#define ATOMIC_OPS(op, c_op, asm_op) \
+ ATOMIC_OP(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(and, &=, CTOP_INST_AAND_DI_R2_R2_R3)
#define atomic_andnot(mask, v) atomic_and(~(mask), (v))
-ATOMIC_OP(or, |=, CTOP_INST_AOR_DI_R2_R2_R3)
-ATOMIC_OP(xor, ^=, CTOP_INST_AXOR_DI_R2_R2_R3)
+ATOMIC_OPS(or, |=, CTOP_INST_AOR_DI_R2_R2_R3)
+ATOMIC_OPS(xor, ^=, CTOP_INST_AXOR_DI_R2_R2_R3)
#endif /* CONFIG_ARC_PLAT_EZNPS */
#undef ATOMIC_OPS
+#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
next prev parent reply other threads:[~2016-05-31 10:30 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-31 10:19 [PATCH -v2 00/33] implement atomic_fetch_$op Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 01/33] locking,alpha: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` Peter Zijlstra [this message]
2016-05-31 10:19 ` [PATCH -v2 03/33] locking,arm: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 04/33] locking,arm64: " Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 05/33] arm64: atomic: generate LSE non-return cases using common macros Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 06/33] locking,arm64: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() for LSE instructions Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 07/33] locking,avr32: Implement atomic_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 08/33] locking,blackfin: " Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 09/33] locking,frv: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 10/33] locking,h8300: Implement atomic_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 11/33] locking,hexagon: " Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 12/33] locking,ia64: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 13/33] locking,m32r: Implement atomic_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 14/33] locking,m68k: " Peter Zijlstra
2016-06-16 10:08 ` Geert Uytterhoeven
2016-06-16 10:13 ` Peter Zijlstra
2016-06-16 12:43 ` Andreas Schwab
2016-06-16 12:49 ` Peter Zijlstra
2016-06-16 12:53 ` Andreas Schwab
2016-06-16 14:35 ` Peter Zijlstra
2016-06-16 14:37 ` Andreas Schwab
2016-06-16 14:56 ` Peter Zijlstra
2016-06-16 15:04 ` Andreas Schwab
2016-06-16 17:44 ` Peter Zijlstra
2016-06-16 19:18 ` Andreas Schwab
2016-06-16 19:55 ` Geert Uytterhoeven
2016-06-17 15:40 ` Peter Zijlstra
2016-06-20 17:47 ` Andreas Schwab
2016-06-21 4:27 ` Finn Thain
2016-05-31 10:19 ` [PATCH -v2 15/33] locking,metag: " Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 16/33] locking,mips: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 17/33] locking,mn10300: Implement atomic_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 18/33] locking,parisc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 19/33] locking,powerpc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}{,_relaxed,_acquire,_release}() Peter Zijlstra
2016-06-01 3:11 ` Boqun Feng
2016-06-01 6:10 ` Boqun Feng
2016-06-01 8:46 ` Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 20/33] locking,s390: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 21/33] locking,sh: Implement atomic_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 22/33] locking,sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 17:50 ` David Miller
2016-05-31 10:19 ` [PATCH -v2 23/33] locking,tile: " Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 24/33] locking,x86: " Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 25/33] locking,xtensa: Implement atomic_fetch_{add,sub,and,or,xor}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 26/33] locking: Fix atomic64_relaxed bits Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 27/33] locking: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 28/33] locking: Remove linux/atomic.h:atomic_fetch_or Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 29/33] locking: Remove the deprecated atomic_{set,clear}_mask() functions Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 30/33] locking,alpha: Convert to _relaxed atomics Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 31/33] locking,mips: " Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 32/33] locking,qrwlock: Employ atomic_fetch_add_acquire() Peter Zijlstra
2016-05-31 10:19 ` [PATCH -v2 33/33] locking,rwsem: Employ atomic_long_fetch_add() Peter Zijlstra
2016-06-01 14:06 ` [PATCH -v2 00/33] implement atomic_fetch_$op Will Deacon
2016-06-02 9:27 ` Vineet Gupta
2016-06-02 9:33 ` Peter Zijlstra
2016-06-08 12:43 ` Peter Zijlstra
2016-06-08 12:55 ` Ingo Molnar
2016-06-08 13:32 ` Peter Zijlstra
2016-06-08 14:24 ` Vineet Gupta
2016-06-08 14:38 ` Peter Zijlstra
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