From: Mark Rutland <mark.rutland@arm.com>
To: linux-kernel@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>,
Boqun Feng <boqun.feng@gmail.com>,
Will Deacon <will.deacon@arm.com>,
Richard Henderson <rth@twiddle.net>,
Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
Matt Turner <mattst88@gmail.com>
Subject: [PATCHv2 07/16] atomics/alpha: define atomic64_fetch_add_unless()
Date: Tue, 29 May 2018 16:43:37 +0100 [thread overview]
Message-ID: <20180529154346.3168-8-mark.rutland@arm.com> (raw)
In-Reply-To: <20180529154346.3168-1-mark.rutland@arm.com>
As a step towards unifying the atomic/atomic64/atomic_long APIs, this
patch converts the arch/alpha implementation of atomic64_add_unless() into
an implementation of atomic64_fetch_add_unless().
A wrapper in <linux/atomic.h> will build atomic_add_unless() atop of
this, provided it is given a preprocessor definition.
No functional change is intended as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
---
arch/alpha/include/asm/atomic.h | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/arch/alpha/include/asm/atomic.h b/arch/alpha/include/asm/atomic.h
index 4a800a3424a3..dcb7bbeeae02 100644
--- a/arch/alpha/include/asm/atomic.h
+++ b/arch/alpha/include/asm/atomic.h
@@ -238,35 +238,36 @@ static __inline__ int atomic_fetch_add_unless(atomic_t *v, int a, int u)
#define atomic_fetch_add_unless atomic_fetch_add_unless
/**
- * atomic64_add_unless - add unless the number is a given value
+ * atomic64_fetch_add_unless - add unless the number is a given value
* @v: pointer of type atomic64_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns true iff @v was not @u.
+ * Returns the old value of @v.
*/
-static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
+static __inline__ int atomic64_fetch_add_unless(atomic64_t *v, long a, long u)
{
- long c, tmp;
+ long c, new, old;
smp_mb();
__asm__ __volatile__(
- "1: ldq_l %[tmp],%[mem]\n"
- " cmpeq %[tmp],%[u],%[c]\n"
- " addq %[tmp],%[a],%[tmp]\n"
+ "1: ldq_l %[old],%[mem]\n"
+ " cmpeq %[old],%[u],%[c]\n"
+ " addq %[old],%[a],%[new]\n"
" bne %[c],2f\n"
- " stq_c %[tmp],%[mem]\n"
- " beq %[tmp],3f\n"
+ " stq_c %[new],%[mem]\n"
+ " beq %[new],3f\n"
"2:\n"
".subsection 2\n"
"3: br 1b\n"
".previous"
- : [tmp] "=&r"(tmp), [c] "=&r"(c)
+ : [old] "=&r"(old), [new] "=&r"(new), [c] "=&r"(c)
: [mem] "m"(*v), [a] "rI"(a), [u] "rI"(u)
: "memory");
smp_mb();
- return !c;
+ return old;
}
+#define atomic64_fetch_add_unless atomic64_fetch_add_unless
/*
* atomic64_dec_if_positive - decrement by 1 if old value positive
--
2.11.0
next prev parent reply other threads:[~2018-05-29 15:44 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-29 15:43 [PATCHv2 00/16] atomics: API cleanups Mark Rutland
2018-05-29 15:43 ` [PATCHv2 01/16] atomics/treewide: s/__atomic_add_unless/atomic_fetch_add_unless/ Mark Rutland
2018-06-04 23:24 ` Palmer Dabbelt
2018-05-29 15:43 ` [PATCHv2 02/16] atomics/treewide: remove redundant atomic_inc_not_zero() definitions Mark Rutland
2018-06-04 23:24 ` Palmer Dabbelt
2018-05-29 15:43 ` [PATCHv2 03/16] atomics/treewide: make atomic64_inc_not_zero() optional Mark Rutland
2018-06-04 23:17 ` Palmer Dabbelt
2018-06-05 5:34 ` Mark Rutland
2018-05-29 15:43 ` [PATCHv2 04/16] atomics/treewide: make atomic_fetch_add_unless() optional Mark Rutland
2018-06-04 23:24 ` Palmer Dabbelt
2018-05-29 15:43 ` [PATCHv2 05/16] atomics: prepare for atomic64_fetch_add_unless() Mark Rutland
2018-06-05 9:26 ` Peter Zijlstra
2018-06-05 9:53 ` Mark Rutland
2018-06-05 10:54 ` Michael Ellerman
2018-06-05 11:08 ` Mark Rutland
2018-06-06 8:57 ` Michael Ellerman
2018-05-29 15:43 ` [PATCHv2 06/16] atomics/generic: define atomic64_fetch_add_unless() Mark Rutland
2018-05-29 15:43 ` Mark Rutland [this message]
2018-05-29 15:43 ` [PATCHv2 08/16] atomics/arc: " Mark Rutland
2018-05-29 15:43 ` [PATCHv2 09/16] atomics/arm: " Mark Rutland
2018-05-29 15:43 ` [PATCHv2 10/16] atomics/powerpc: " Mark Rutland
2018-05-29 15:43 ` [PATCHv2 11/16] atomics/riscv: " Mark Rutland
2018-06-04 23:17 ` Palmer Dabbelt
2018-05-29 15:43 ` [PATCHv2 12/16] atomics/treewide: make atomic64_fetch_add_unless() optional Mark Rutland
2018-05-29 15:43 ` [PATCHv2 13/16] atomics/treewide: make test ops optional Mark Rutland
2018-06-04 23:17 ` Palmer Dabbelt
2018-05-29 15:43 ` [PATCHv2 14/16] atomics/treewide: remove atomic_inc_not_zero_hint() Mark Rutland
2018-05-29 15:43 ` [PATCHv2 15/16] atomics/treewide: make unconditional inc/dec ops optional Mark Rutland
2018-06-04 23:17 ` Palmer Dabbelt
2018-05-29 15:43 ` [PATCHv2 16/16] atomics/treewide: make conditional " Mark Rutland
2018-05-30 11:23 ` [PATCHv2 00/16] atomics: API cleanups Mark Rutland
2018-05-30 13:34 ` Mark Rutland
2018-06-05 9:43 ` Peter Zijlstra
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=20180529154346.3168-8-mark.rutland@arm.com \
--to=mark.rutland@arm.com \
--cc=boqun.feng@gmail.com \
--cc=ink@jurassic.park.msu.ru \
--cc=linux-kernel@vger.kernel.org \
--cc=mattst88@gmail.com \
--cc=rth@twiddle.net \
--cc=will.deacon@arm.com \
/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).