Re: [PATCH 2/2] ARC: mm: fix new code about cache aliasing

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2024-03-28 01:39, Vineet Gupta wrote:
Manual/partial revert of 8690bbcf3b70 ("Introduce cpu_dcache_is_aliasing() across all architectures")

Current generation of ARCv2/ARCv3 based HSxx cores are only PIPT (to software
at least).

Legacy ARC700 cpus could be VIPT aliasing (based on cache geometry and
PAGE_SIZE) however recently that support was ripped out so VIPT aliasing
cache is not relevant to ARC anymore.

P.S. : This has been discussed a few times on lists [1]
P.S.2: Please CC the arch maintainers and/or mailing list before adding
        such interfaces.

Because 8690bbcf3b70 was introducing a tree-wide change affecting all
architectures, I CC'd linux-arch@xxxxxxxxxxxxxxx. I expected all
architecture maintainers to follow that list, which is relatively
low volume.

I'm sorry that you learn about this after the fact as a result.
My intent was to use the list rather than CC about 50 additional
people/mailing lists.

Of course, if VIPT aliasing is removed from ARC, removing the
config ARCH_HAS_CPU_CACHE_ALIASING and using the generic
cpu_dcache_is_aliasing() is the way to go. Feel free to add
my:

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>

Thanks,

Mathieu



[1] http://lists.infradead.org/pipermail/linux-snps-arc/2023-February/006899.html

Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxx>
---
  arch/arc/Kconfig                 | 1 -
  arch/arc/include/asm/cachetype.h | 9 ---------
  2 files changed, 10 deletions(-)
  delete mode 100644 arch/arc/include/asm/cachetype.h

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 99d2845f3feb..4092bec198be 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -6,7 +6,6 @@
  config ARC
  	def_bool y
  	select ARC_TIMERS
-	select ARCH_HAS_CPU_CACHE_ALIASING
  	select ARCH_HAS_CACHE_LINE_SIZE
  	select ARCH_HAS_DEBUG_VM_PGTABLE
  	select ARCH_HAS_DMA_PREP_COHERENT
diff --git a/arch/arc/include/asm/cachetype.h b/arch/arc/include/asm/cachetype.h
deleted file mode 100644
index 05fc7ed59712..000000000000
--- a/arch/arc/include/asm/cachetype.h
+++ /dev/null
@@ -1,9 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __ASM_ARC_CACHETYPE_H
-#define __ASM_ARC_CACHETYPE_H
-
-#include <linux/types.h>
-
-#define cpu_dcache_is_aliasing()	true
-
-#endif

--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com





[Index of Archives]     [Linux Kernel]     [Kernel Newbies]     [x86 Platform Driver]     [Netdev]     [Linux Wireless]     [Netfilter]     [Bugtraq]     [Linux Filesystems]     [Yosemite Discussion]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]

  Powered by Linux