From: Vineet Gupta <Vineet.Gupta1@synopsys.com>
To: linux-snps-arc@lists.infradead.org
Cc: Peter Zijlstra <peterz@infradead.org>,
Will Deacon <will@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
Mark Rutland <mark.rutland@arm.com>,
linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
Vladimir Isaev <Vladimir.Isaev@synopsys.com>,
Vineet Gupta <Vineet.Gupta1@synopsys.com>
Subject: [PATCH 11/11] ARC: atomic_cmpxchg/atomic_xchg: implement relaxed variants
Date: Wed, 4 Aug 2021 12:15:54 -0700 [thread overview]
Message-ID: <20210804191554.1252776-12-vgupta@synopsys.com> (raw)
In-Reply-To: <20210804191554.1252776-1-vgupta@synopsys.com>
And move them out of cmpxchg.h to canonical atomic.h
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
---
arch/arc/include/asm/atomic.h | 27 +++++++++++++++++++++++++++
arch/arc/include/asm/cmpxchg.h | 23 -----------------------
2 files changed, 27 insertions(+), 23 deletions(-)
diff --git a/arch/arc/include/asm/atomic.h b/arch/arc/include/asm/atomic.h
index ee88e1dbaab5..52ee51e1ff7c 100644
--- a/arch/arc/include/asm/atomic.h
+++ b/arch/arc/include/asm/atomic.h
@@ -22,6 +22,33 @@
#include <asm/atomic-spinlock.h>
#endif
+#define arch_atomic_cmpxchg(v, o, n) \
+({ \
+ arch_cmpxchg(&((v)->counter), (o), (n)); \
+})
+
+#ifdef arch_cmpxchg_relaxed
+#define arch_atomic_cmpxchg_relaxed(v, o, n) \
+({ \
+ arch_cmpxchg_relaxed(&((v)->counter), (o), (n)); \
+})
+#endif
+
+#define arch_atomic_xchg(v, n) \
+({ \
+ arch_xchg(&((v)->counter), (n)); \
+})
+
+#ifdef arch_xchg_relaxed
+#define arch_atomic_xchg_relaxed(v, n) \
+({ \
+ arch_xchg_relaxed(&((v)->counter), (n)); \
+})
+#endif
+
+/*
+ * 64-bit atomics
+ */
#ifdef CONFIG_GENERIC_ATOMIC64
#include <asm-generic/atomic64.h>
#else
diff --git a/arch/arc/include/asm/cmpxchg.h b/arch/arc/include/asm/cmpxchg.h
index e2ae0eb1ca07..c5b544a5fe81 100644
--- a/arch/arc/include/asm/cmpxchg.h
+++ b/arch/arc/include/asm/cmpxchg.h
@@ -80,14 +80,6 @@
#endif
-/*
- * atomic_cmpxchg is same as cmpxchg
- * LLSC: only different in data-type, semantics are exactly same
- * !LLSC: cmpxchg() has to use an external lock atomic_ops_lock to guarantee
- * semantics, and this lock also happens to be used by atomic_*()
- */
-#define arch_atomic_cmpxchg(v, o, n) ((int)arch_cmpxchg(&((v)->counter), (o), (n)))
-
/*
* xchg
*/
@@ -148,19 +140,4 @@
#endif
-/*
- * "atomic" variant of xchg()
- * REQ: It needs to follow the same serialization rules as other atomic_xxx()
- * Since xchg() doesn't always do that, it would seem that following definition
- * is incorrect. But here's the rationale:
- * SMP : Even xchg() takes the atomic_ops_lock, so OK.
- * LLSC: atomic_ops_lock are not relevant at all (even if SMP, since LLSC
- * is natively "SMP safe", no serialization required).
- * UP : other atomics disable IRQ, so no way a difft ctxt atomic_xchg()
- * could clobber them. atomic_xchg() itself would be 1 insn, so it
- * can't be clobbered by others. Thus no serialization required when
- * atomic_xchg is involved.
- */
-#define arch_atomic_xchg(v, new) (arch_xchg(&((v)->counter), new))
-
#endif
--
2.25.1
next prev parent reply other threads:[~2021-08-04 19:16 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-04 19:15 [PATCH 00/11] ARC atomics update Vineet Gupta
2021-08-04 19:15 ` [PATCH 01/11] ARC: atomics: disintegrate header Vineet Gupta
2021-08-04 19:15 ` [PATCH 02/11] ARC: atomic: !LLSC: remove hack in atomic_set() for for UP Vineet Gupta
2021-08-04 19:15 ` [PATCH 03/11] ARC: atomic: !LLSC: use int data type consistently Vineet Gupta
2021-08-04 19:15 ` [PATCH 04/11] ARC: atomic64: LLSC: elide unused atomic_{and,or,xor,andnot}_return Vineet Gupta
2021-08-04 19:15 ` [PATCH 05/11] ARC: atomics: implement relaxed variants Vineet Gupta
2021-08-04 19:15 ` [PATCH 06/11] ARC: switch to generic bitops Vineet Gupta
2021-08-04 19:15 ` [PATCH 07/11] ARC: bitops: fls/ffs to take int (vs long) per asm-generic defines Vineet Gupta
2021-08-04 19:15 ` [PATCH 08/11] ARC: xchg: !LLSC: remove UP micro-optimization/hack Vineet Gupta
2021-08-04 19:15 ` [PATCH 09/11] ARC: cmpxchg/xchg: rewrite as macros to make type safe Vineet Gupta
2021-08-04 19:15 ` [PATCH 10/11] ARC: cmpxchg/xchg: implement relaxed variants (LLSC config only) Vineet Gupta
2021-08-04 19:15 ` Vineet Gupta [this message]
2021-08-05 9:02 ` [PATCH 00/11] ARC atomics update Peter Zijlstra
2021-08-05 16:18 ` Vineet Gupta
2021-08-05 17:04 ` Peter Zijlstra
2021-08-05 19:14 ` [RFC] bitops/non-atomic: make @nr unsigned to avoid any DIV Vineet Gupta
2021-08-06 13:42 ` Will Deacon
2021-08-06 19:02 ` Vineet Gupta
2021-08-06 8:41 ` [PATCH 00/11] ARC atomics update Will Deacon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210804191554.1252776-12-vgupta@synopsys.com \
--to=vineet.gupta1@synopsys.com \
--cc=Vladimir.Isaev@synopsys.com \
--cc=arnd@arndb.de \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-snps-arc@lists.infradead.org \
--cc=mark.rutland@arm.com \
--cc=peterz@infradead.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).