[PATCH 08/33] locking/atomic: atomic: simplify ifdeffery

From: Mark Rutland <mark.rutland@arm.com>
To: linux-kernel@vger.kernel.org, will@kernel.org,
	boqun.feng@gmail.com, peterz@infradead.org
Cc: aou@eecs.berkeley.edu, arnd@arndb.de, bcain@codeaurora.org,
	benh@kernel.crashing.org, chris@zankel.net, dalias@libc.org,
	davem@davemloft.net, deanbo422@gmail.com, deller@gmx.de,
	geert@linux-m68k.org, green.hu@gmail.com, guoren@kernel.org,
	ink@jurassic.park.msu.ru, James.Bottomley@HansenPartnership.com,
	jcmvbkbc@gmail.com, jonas@southpole.se, ley.foon.tan@intel.com,
	linux@armlinux.org.uk, mark.rutland@arm.com, mattst88@gmail.com,
	monstr@monstr.eu, mpe@ellerman.id.au, nickhu@andestech.com,
	palmer@dabbelt.com, paulus@samba.org, paul.walmsley@sifive.com,
	rth@twiddle.net, shorne@gmail.com,
	stefan.kristiansson@saunalahti.fi, tsbogend@alpha.franken.de,
	vgupta@synopsys.com, ysato@users.sourceforge.jp
Subject: [PATCH 08/33] locking/atomic: atomic: simplify ifdeffery
Date: Mon, 10 May 2021 10:37:28 +0100	[thread overview]
Message-ID: <20210510093753.40683-9-mark.rutland@arm.com> (raw)
In-Reply-To: <20210510093753.40683-1-mark.rutland@arm.com>

Now that asm-generic/atomic.h is only used by architectures without any
architecture-specific atomic definitions, we know that there will be no
architecture-specific implementations to override, and can remove the
ifdeffery this has previously required, bringing it into line with
asm-generic/atomic64.h.

At the same time, we can implement atomic_add() and atomic_sub()
directly using ATOMIC_OP(), since we know architectures won't provide
atomic_add_return() or atomic_sub_return().

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
---
 include/asm-generic/atomic.h | 46 ++++----------------------------------------
 1 file changed, 4 insertions(+), 42 deletions(-)

diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index d4bf803d6491..316c82a27b0a 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h
@@ -93,65 +93,27 @@ static inline int atomic_fetch_##op(int i, atomic_t *v)			\
 
 #endif /* CONFIG_SMP */
 
-#ifndef atomic_add_return
 ATOMIC_OP_RETURN(add, +)
-#endif
-
-#ifndef atomic_sub_return
 ATOMIC_OP_RETURN(sub, -)
-#endif
 
-#ifndef atomic_fetch_add
 ATOMIC_FETCH_OP(add, +)
-#endif
-
-#ifndef atomic_fetch_sub
 ATOMIC_FETCH_OP(sub, -)
-#endif
-
-#ifndef atomic_fetch_and
 ATOMIC_FETCH_OP(and, &)
-#endif
-
-#ifndef atomic_fetch_or
 ATOMIC_FETCH_OP(or, |)
-#endif
-
-#ifndef atomic_fetch_xor
 ATOMIC_FETCH_OP(xor, ^)
-#endif
 
-#ifndef atomic_and
+ATOMIC_OP(add, +)
+ATOMIC_OP(sub, -)
 ATOMIC_OP(and, &)
-#endif
-
-#ifndef atomic_or
 ATOMIC_OP(or, |)
-#endif
-
-#ifndef atomic_xor
 ATOMIC_OP(xor, ^)
-#endif
 
 #undef ATOMIC_FETCH_OP
 #undef ATOMIC_OP_RETURN
 #undef ATOMIC_OP
 
-#ifndef atomic_read
-#define atomic_read(v)	READ_ONCE((v)->counter)
-#endif
-
-#define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
-
-static inline void atomic_add(int i, atomic_t *v)
-{
-	atomic_add_return(i, v);
-}
-
-static inline void atomic_sub(int i, atomic_t *v)
-{
-	atomic_sub_return(i, v);
-}
+#define atomic_read(v)			READ_ONCE((v)->counter)
+#define atomic_set(v, i)		WRITE_ONCE(((v)->counter), (i))
 
 #define atomic_xchg(ptr, v)		(xchg(&(ptr)->counter, (v)))
 #define atomic_cmpxchg(v, old, new)	(cmpxchg(&((v)->counter), (old), (new)))
-- 
2.11.0

