From: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
To: Arnd Bergmann <arnd@kernel.org>, linux-arch@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Vineet Gupta <vgupta@synopsys.com>, Arnd Bergmann <arnd@arndb.de>,
Yoshinori Sato <ysato@users.sourceforge.jp>,
Rich Felker <dalias@libc.org>,
linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 03/13] sh: remove unaligned access for sh4a
Date: Fri, 14 May 2021 12:34:32 +0200 [thread overview]
Message-ID: <3d70eb2a-2969-197e-63e8-f3e0a6a8ddd8@physik.fu-berlin.de> (raw)
In-Reply-To: <20210514100106.3404011-4-arnd@kernel.org>
Hi Arnd!
On 5/14/21 12:00 PM, Arnd Bergmann wrote:
> Unlike every other architecture, sh4a uses an inline asm implementation
> for get_unaligned(). I have shown that this produces better object
> code than the asm-generic version. However, there are very few users of
> arch/sh/ overall, and most of those seem to use sh4 rather than sh4a CPU
> cores, so it seems not worth keeping the complexity in the architecture
> independent code.
My Renesas SH4-Boards actually run an sh4a-Kernel, not an sh4-Kernel:
root@tirpitz:~> uname -a
Linux tirpitz 5.11.0-rc4-00012-g10c03c5bf422 #161 PREEMPT Mon Jan 18 21:10:17 CET 2021 sh4a GNU/Linux
root@tirpitz:~>
So, if this change reduces performance on sh4a, I would rather not merge it.
Adrian
--
.''`. John Paul Adrian Glaubitz
: :' : Debian Developer - glaubitz@debian.org
`. `' Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
`- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
next prev parent reply other threads:[~2021-05-14 10:34 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-14 10:00 [PATCH v2 00/13] Unify asm/unaligned.h around struct helper Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 01/13] asm-generic: use asm-generic/unaligned.h for most architectures Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 02/13] openrisc: always use unaligned-struct header Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 03/13] sh: remove unaligned access for sh4a Arnd Bergmann
2021-05-14 10:34 ` John Paul Adrian Glaubitz [this message]
2021-05-14 12:22 ` Arnd Bergmann
2021-05-15 15:36 ` John Paul Adrian Glaubitz
2021-05-15 20:10 ` Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 04/13] m68k: select CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 05/13] powerpc: use linux/unaligned/le_struct.h on LE power7 Arnd Bergmann
2021-05-14 11:48 ` Segher Boessenkool
2021-05-14 13:02 ` Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 06/13] asm-generic: unaligned: remove byteshift helpers Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 07/13] asm-generic: unaligned always use struct helpers Arnd Bergmann
2021-05-17 21:53 ` Eric Biggers
2021-05-18 7:25 ` Arnd Bergmann
2021-05-18 14:56 ` Linus Torvalds
2021-05-18 15:41 ` Arnd Bergmann
2021-05-18 16:12 ` Linus Torvalds
2021-05-18 18:09 ` Jason A. Donenfeld
2021-05-18 20:51 ` Arnd Bergmann
2021-05-18 21:31 ` Eric Biggers
2021-05-18 21:14 ` David Laight
2021-05-14 10:00 ` [PATCH v2 08/13] partitions: msdos: fix one-byte get_unaligned() Arnd Bergmann
2021-05-17 10:28 ` Christoph Hellwig
2021-05-17 10:44 ` Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 09/13] apparmor: use get_unaligned() only for multi-byte words Arnd Bergmann
2021-05-14 10:00 ` [PATCH v2 10/13] mwifiex: re-fix for unaligned accesses Arnd Bergmann
2021-05-15 6:22 ` Kalle Valo
2021-05-15 9:01 ` Arnd Bergmann
2021-05-15 18:23 ` Kalle Valo
2021-05-14 10:00 ` [PATCH v2 11/13] netpoll: avoid put_unaligned() on single character Arnd Bergmann
2021-05-14 10:01 ` [PATCH v2 12/13] asm-generic: uaccess: 1-byte access is always aligned Arnd Bergmann
2021-05-15 18:41 ` Randy Dunlap
2021-05-15 20:16 ` Arnd Bergmann
2021-05-14 10:01 ` [PATCH v2 13/13] asm-generic: simplify asm/unaligned.h Arnd Bergmann
2021-05-14 10:35 ` David Laight
2021-05-14 17:32 ` [PATCH v2 00/13] Unify asm/unaligned.h around struct helper Linus Torvalds
2021-05-14 18:51 ` Vineet Gupta
2021-05-14 19:22 ` Linus Torvalds
2021-05-14 19:45 ` Vineet Gupta
2021-05-14 20:19 ` Linus Torvalds
2021-05-14 19:31 ` Arnd Bergmann
2021-12-16 17:29 ` Ard Biesheuvel
2021-12-16 17:42 ` Linus Torvalds
2021-12-16 17:49 ` David Laight
2021-12-16 18:56 ` Segher Boessenkool
2021-12-17 12:34 ` David Laight
2021-12-17 13:35 ` Segher Boessenkool
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