From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:54607)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <alex.bennee@linaro.org>) id 1ast2r-0004YT-Nq
	for qemu-devel@nongnu.org; Wed, 20 Apr 2016 10:24:01 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <alex.bennee@linaro.org>) id 1ast2m-000447-4Z
	for qemu-devel@nongnu.org; Wed, 20 Apr 2016 10:23:57 -0400
Received: from mail-wm0-x234.google.com ([2a00:1450:400c:c09::234]:38635)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <alex.bennee@linaro.org>) id 1ast2l-00043z-UN
	for qemu-devel@nongnu.org; Wed, 20 Apr 2016 10:23:52 -0400
Received: by mail-wm0-x234.google.com with SMTP id u206so84436316wme.1
	for <qemu-devel@nongnu.org>; Wed, 20 Apr 2016 07:23:51 -0700 (PDT)
References: <1460044433-19282-1-git-send-email-sergey.fedorov@linaro.org>
	<1460044433-19282-10-git-send-email-sergey.fedorov@linaro.org>
From: Alex =?utf-8?Q?Benn=C3=A9e?= <alex.bennee@linaro.org>
In-reply-to: <1460044433-19282-10-git-send-email-sergey.fedorov@linaro.org>
Date: Wed, 20 Apr 2016 15:23:49 +0100
Message-ID: <87inzcuznu.fsf@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Subject: Re: [Qemu-devel] [PATCH 09/11] tcg/sparc: Make direct jump patching
 thread-safe
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel/>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Sergey Fedorov <sergey.fedorov@linaro.org>
Cc: qemu-devel@nongnu.org, Sergey Fedorov <serge.fdrv@gmail.com>, Paolo Bonzini <pbonzini@redhat.com>, Peter Crosthwaite <crosthwaite.peter@gmail.com>, Richard Henderson <rth@twiddle.net>, Blue Swirl <blauwirbel@gmail.com>


Sergey Fedorov <sergey.fedorov@linaro.org> writes:

> From: Sergey Fedorov <serge.fdrv@gmail.com>
>
> Ensure direct jump patching in SPARC is atomic by using
> atomic_read()/atomic_set() for code patching.
>
> Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
> Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
> ---
>  tcg/sparc/tcg-target.inc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tcg/sparc/tcg-target.inc.c b/tcg/sparc/tcg-target.inc.c
> index 54df1bc42432..629dd7bdafff 100644
> --- a/tcg/sparc/tcg-target.inc.c
> +++ b/tcg/sparc/tcg-target.inc.c
> @@ -1647,6 +1647,6 @@ void tb_set_jmp_target1(uintptr_t jmp_addr, uintptr_t addr)
>         the code_gen_buffer can't be larger than 2GB.  */
>      assert(disp == (int32_t)disp);
>
> -    *ptr = CALL | (uint32_t)disp >> 2;
> +    atomic_set(ptr, CALL | (uint32_t)disp >> 2);

atomic_set(ptr, deposit32(CALL, 0, 30, disp >> 2))

might be a little more explicit.

Otherwise:

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>


>      flush_icache_range(jmp_addr, jmp_addr + 4);
>  }


--
Alex Bennée