From: Heiko Carstens <heiko.carstens@de.ibm.com>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: mark.rutland@arm.com, peterz@infradead.org, mingo@redhat.com,
will.deacon@arm.com, akpm@linux-foundation.org,
aryabinin@virtuozzo.com, kasan-dev@googlegroups.com,
linux-kernel@vger.kernel.org, x86@kernel.org, tglx@linutronix.de,
hpa@zytor.com, willy@infradead.org, linux-mm@kvack.org
Subject: Re: [PATCH v2 2/7] x86: use long long for 64-bit atomic ops
Date: Mon, 29 May 2017 12:49:16 +0200 [thread overview]
Message-ID: <20170529104916.GB12975@osiris> (raw)
In-Reply-To: <3758f3da9de01b1a082c4e1f44ba3b48f7a840ea.1495825151.git.dvyukov@google.com>
On Fri, May 26, 2017 at 09:09:04PM +0200, Dmitry Vyukov wrote:
> Some 64-bit atomic operations use 'long long' as operand/return type
> (e.g. asm-generic/atomic64.h, arch/x86/include/asm/atomic64_32.h);
> while others use 'long' (e.g. arch/x86/include/asm/atomic64_64.h).
> This makes it impossible to write portable code.
> For example, there is no format specifier that prints result of
> atomic64_read() without warnings. atomic64_try_cmpxchg() is almost
> impossible to use in portable fashion because it requires either
> 'long *' or 'long long *' as argument depending on arch.
>
> Switch arch/x86/include/asm/atomic64_64.h to 'long long'.
>
> Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
>
> ---
> Changes since v1:
> - reverted stray s/long/long long/ replace in comment
> - added arch/s390 changes to fix build errors/warnings
If you change s390 code, please add the relevant mailing list and/or
maintainers please.
> diff --git a/arch/s390/include/asm/atomic_ops.h b/arch/s390/include/asm/atomic_ops.h
> index ac9e2b939d04..055a9083e52d 100644
> --- a/arch/s390/include/asm/atomic_ops.h
> +++ b/arch/s390/include/asm/atomic_ops.h
> @@ -31,10 +31,10 @@ __ATOMIC_OPS(__atomic_and, int, "lan")
> __ATOMIC_OPS(__atomic_or, int, "lao")
> __ATOMIC_OPS(__atomic_xor, int, "lax")
>
> -__ATOMIC_OPS(__atomic64_add, long, "laag")
> -__ATOMIC_OPS(__atomic64_and, long, "lang")
> -__ATOMIC_OPS(__atomic64_or, long, "laog")
> -__ATOMIC_OPS(__atomic64_xor, long, "laxg")
> +__ATOMIC_OPS(__atomic64_add, long long, "laag")
> +__ATOMIC_OPS(__atomic64_and, long long, "lang")
> +__ATOMIC_OPS(__atomic64_or, long long, "laog")
> +__ATOMIC_OPS(__atomic64_xor, long long, "laxg")
>
> #undef __ATOMIC_OPS
> #undef __ATOMIC_OP
> @@ -46,7 +46,7 @@ static inline void __atomic_add_const(int val, int *ptr)
> : [ptr] "+Q" (*ptr) : [val] "i" (val) : "cc");
> }
>
> -static inline void __atomic64_add_const(long val, long *ptr)
> +static inline void __atomic64_add_const(long val, long long *ptr)
If you change this then val should be long long (or s64) too.
> -static inline long op_name(long val, long *ptr) \
> +static inline long op_name(long val, long long *ptr) \
> { \
> long old, new; \
Same here. You only changed the type of *ptr, but left the rest
alone. Everything should have the same type.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2017-05-29 10:49 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1495825151.git.dvyukov@google.com>
2017-05-26 19:09 ` [PATCH v2 2/7] x86: use long long for 64-bit atomic ops Dmitry Vyukov
2017-05-27 23:02 ` hpa
2017-05-28 9:29 ` Dmitry Vyukov
2017-05-28 9:34 ` hpa
2017-05-29 14:44 ` Dmitry Vyukov
2017-06-06 10:12 ` Dmitry Vyukov
2017-05-29 10:49 ` Heiko Carstens [this message]
2017-05-29 11:03 ` Dmitry Vyukov
2017-05-26 19:09 ` [PATCH v2 3/7] asm-generic: add atomic-instrumented.h Dmitry Vyukov
2017-05-26 19:09 ` [PATCH v2 4/7] x86: switch atomic.h to use atomic-instrumented.h Dmitry Vyukov
2017-05-26 19:09 ` [PATCH v2 5/7] kasan: allow kasan_check_read/write() to accept pointers to volatiles Dmitry Vyukov
2017-05-26 19:09 ` [PATCH v2 6/7] asm-generic: add KASAN instrumentation to atomic operations Dmitry Vyukov
2017-05-26 19:09 ` [PATCH v2 7/7] asm-generic, x86: add comments for atomic instrumentation Dmitry Vyukov
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=20170529104916.GB12975@osiris \
--to=heiko.carstens@de.ibm.com \
--cc=akpm@linux-foundation.org \
--cc=aryabinin@virtuozzo.com \
--cc=dvyukov@google.com \
--cc=hpa@zytor.com \
--cc=kasan-dev@googlegroups.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mark.rutland@arm.com \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=will.deacon@arm.com \
--cc=willy@infradead.org \
--cc=x86@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).