From: "Linas Vepstas (Code Aurora)" <linas@codeaurora.org>
To: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-arch@vger.kernel.org, linux-hexagon@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [patch v3 24/36] Hexagon: Provide basic implementation and/or stubs for I/O routines.
Date: Fri, 9 Sep 2011 14:14:13 -0500 [thread overview]
Message-ID: <20110909191412.GB2034@codeaurora.org> (raw)
In-Reply-To: <20110909010916.993872033@codeaurora.org>
On Thu, Sep 08, 2011 at 08:09:11PM -0500, Richard Kuo wrote:
> + asm volatile(
> + "memb(%0) = %1;"
> + :
> + : "r" (addr), "r" (data)
> + );
I'm kind-of vague on this, but I think that this also needs a
: "memory" at the end (to indicate that the asm snippet clobbers
memory), as otherwise the compiler may be tempted to reorder
these around other memory accesses. That is, the "volatile"
keyword is not enough (well, I'm not sure...), but I think
"volatile" only prevents the compiler from optimizing these
away completely, but is not enough to prevent unwanted
re-ordering.
--linas
--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.
next prev parent reply other threads:[~2011-09-09 19:14 UTC|newest]
Thread overview: 124+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-09 1:08 [patch v3 00/36] Hexagon: Add support for Qualcomm Hexagon architecture Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 01/36] Hexagon: Add generic headers Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 02/36] Hexagon: Core arch-specific header files Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 03/36] Hexagon: Add bitops support Richard Kuo
2011-09-09 1:08 ` [patch v3 04/36] Hexagon: Add atomic ops support Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 05/36] Hexagon: Add syscalls Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 8:05 ` Arnd Bergmann
2011-09-09 1:08 ` [patch v3 06/36] Hexagon: Add processor and system headers Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 07/36] Hexagon: Add threadinfo Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 08/36] Hexagon: Add delay functions Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 8:07 ` Arnd Bergmann
2011-09-09 8:07 ` Arnd Bergmann
2011-09-09 1:08 ` [patch v3 09/36] Hexagon: Add checksum functions Richard Kuo
2011-09-09 1:08 ` [patch v3 10/36] Hexagon: Add memcpy and memset accelerated functions Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 11/36] Hexagon: Add hypervisor interface Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:08 ` [patch v3 12/36] Hexagon: Export ksyms defined in assembly files Richard Kuo
2011-09-09 1:08 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 13/36] Hexagon: Support dynamic module loading Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 14/36] Hexagon: Add signal functions Richard Kuo
2011-09-09 8:12 ` Arnd Bergmann
2011-09-09 8:12 ` Arnd Bergmann
2011-09-11 14:59 ` Benjamin Herrenschmidt
2011-09-09 1:09 ` [patch v3 15/36] Hexagon: Add init_task and process functions Richard Kuo
2011-09-09 1:09 ` [patch v3 16/36] Hexagon: Add startup code Richard Kuo
2011-09-09 1:09 ` [patch v3 17/36] Hexagon: Add interrupts Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 13:04 ` Thomas Gleixner
2011-09-09 18:57 ` Linas Vepstas (Code Aurora)
2011-09-09 18:57 ` Linas Vepstas (Code Aurora)
2011-09-09 1:09 ` [patch v3 18/36] Hexagon: Add time and timer functions Richard Kuo
2011-09-09 8:23 ` Arnd Bergmann
2011-09-09 8:23 ` Arnd Bergmann
2011-09-09 13:13 ` Thomas Gleixner
2011-09-09 13:13 ` Thomas Gleixner
2011-09-09 1:09 ` [patch v3 19/36] Hexagon: Add ptrace support Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 8:15 ` Arnd Bergmann
2011-09-09 8:15 ` Arnd Bergmann
2011-09-09 20:15 ` Jonas Bonn
2011-09-09 20:15 ` Jonas Bonn
2011-09-09 21:18 ` Linas Vepstas (Code Aurora)
2011-09-10 6:42 ` Jonas Bonn
2011-09-10 6:42 ` Jonas Bonn
2011-09-10 11:21 ` Arnd Bergmann
2011-09-10 11:21 ` Arnd Bergmann
2011-09-10 11:29 ` Pedro Alves
2011-09-10 11:29 ` Pedro Alves
2011-09-19 15:25 ` Linas Vepstas (Code Aurora)
2011-09-21 16:15 ` Pedro Alves
2011-09-21 16:15 ` Pedro Alves
2011-09-21 17:50 ` Linas Vepstas (Code Aurora)
2011-09-21 17:50 ` Linas Vepstas (Code Aurora)
2011-09-21 18:04 ` Pedro Alves
2011-09-21 18:04 ` Pedro Alves
2011-09-09 1:09 ` [patch v3 20/36] Hexagon: Provide basic debugging and system trap support Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 21/36] Hexagon: Add SMP support Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 8:16 ` Arnd Bergmann
2011-09-09 8:16 ` Arnd Bergmann
2011-09-09 13:24 ` Thomas Gleixner
2011-09-09 13:24 ` Thomas Gleixner
2011-09-11 14:51 ` Benjamin Herrenschmidt
2011-09-12 23:38 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 22/36] Hexagon: Add locking types and functions Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 8:17 ` Arnd Bergmann
2011-09-09 8:17 ` Arnd Bergmann
2011-09-09 1:09 ` [patch v3 23/36] Hexagon: Add user access functions Richard Kuo
2011-09-09 1:09 ` [patch v3 24/36] Hexagon: Provide basic implementation and/or stubs for I/O routines Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 8:18 ` Arnd Bergmann
2011-09-09 8:18 ` Arnd Bergmann
2011-09-09 19:14 ` Linas Vepstas (Code Aurora) [this message]
2011-09-09 19:14 ` Linas Vepstas (Code Aurora)
2011-09-09 21:13 ` Arnd Bergmann
2011-09-09 21:13 ` Arnd Bergmann
2011-09-10 20:02 ` Taylor Simpson
2011-09-10 20:02 ` Taylor Simpson
2011-09-11 14:46 ` Benjamin Herrenschmidt
2011-09-11 14:46 ` Benjamin Herrenschmidt
2011-09-09 1:09 ` [patch v3 25/36] Hexagon: Implement basic cache-flush support Richard Kuo
2011-09-09 1:09 ` [patch v3 26/36] Hexagon: Implement basic TLB management routines for Hexagon Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 27/36] Hexagon: Provide DMA implementation Richard Kuo
2011-09-09 1:09 ` [patch v3 28/36] Hexagon: Add ioremap support Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 8:19 ` Arnd Bergmann
2011-09-09 8:19 ` Arnd Bergmann
2011-09-09 1:09 ` [patch v3 29/36] Hexagon: Add page table header files & etc Richard Kuo
2011-09-09 8:20 ` Arnd Bergmann
2011-09-09 1:09 ` [patch v3 30/36] Hexagon: Add page-fault support Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-11 15:08 ` Benjamin Herrenschmidt
2011-09-11 15:08 ` Benjamin Herrenschmidt
2011-09-13 1:34 ` Richard Kuo
2011-09-13 1:34 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 31/36] Hexagon: kgdb support files Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 32/36] Hexagon: Comet platform support Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 33/36] Hexagon: Add configuration and makefiles for the Hexagon architecture Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 34/36] Hexagon: Add basic stacktrace functionality for " Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 1:09 ` [patch v3 35/36] Hexagon: Add self to MAINTAINERS Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 8:21 ` Arnd Bergmann
2011-09-09 8:21 ` Arnd Bergmann
2011-09-09 1:09 ` [patch v3 36/36] Add extra arch overrides to asm-generic/checksum.h Richard Kuo
2011-09-09 1:09 ` Richard Kuo
2011-09-09 8:39 ` [patch v3 00/36] Hexagon: Add support for Qualcomm Hexagon architecture Arnd Bergmann
2011-09-09 8:39 ` Arnd Bergmann
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