+ arm64-allow-kmalloc-caches-aligned-to-the-smaller-cache_line_size.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: arm64: allow kmalloc() caches aligned to the smaller cache_line_size()
has been added to the -mm mm-unstable branch.  Its filename is
     arm64-allow-kmalloc-caches-aligned-to-the-smaller-cache_line_size.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/arm64-allow-kmalloc-caches-aligned-to-the-smaller-cache_line_size.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Catalin Marinas <catalin.marinas@arm.com>
Subject: arm64: allow kmalloc() caches aligned to the smaller cache_line_size()
Date: Mon, 12 Jun 2023 16:31:55 +0100

On arm64, ARCH_DMA_MINALIGN is 128, larger than the cache line size on
most of the current platforms (typically 64).  Define
ARCH_KMALLOC_MINALIGN to 8 (the default for architectures without their
own ARCH_DMA_MINALIGN) and override dma_get_cache_alignment() to return
cache_line_size(), probed at run-time.  The kmalloc() caches will be
limited to the cache line size.  This will allow the additional
kmalloc-{64,192} caches on most arm64 platforms.

Link: https://lkml.kernel.org/r/20230612153201.554742-12-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/arm64/include/asm/cache.h |    3 +++
 1 file changed, 3 insertions(+)

--- a/arch/arm64/include/asm/cache.h~arm64-allow-kmalloc-caches-aligned-to-the-smaller-cache_line_size
+++ a/arch/arm64/include/asm/cache.h
@@ -33,6 +33,7 @@
  * the CPU.
  */
 #define ARCH_DMA_MINALIGN	(128)
+#define ARCH_KMALLOC_MINALIGN	(8)
 
 #ifndef __ASSEMBLY__
 
@@ -90,6 +91,8 @@ static inline int cache_line_size_of_cpu
 
 int cache_line_size(void);
 
+#define dma_get_cache_alignment	cache_line_size
+
 /*
  * Read the effective value of CTR_EL0.
  *
_

Patches currently in -mm which might be from catalin.marinas@arm.com are

mm-slab-decouple-arch_kmalloc_minalign-from-arch_dma_minalign.patch
dma-allow-dma_get_cache_alignment-to-be-overridden-by-the-arch-code.patch
mm-slab-simplify-create_kmalloc_cache-args-and-make-it-static.patch
mm-slab-limit-kmalloc-minimum-alignment-to-dma_get_cache_alignment.patch
drivers-base-use-arch_dma_minalign-instead-of-arch_kmalloc_minalign.patch
drivers-gpu-use-arch_dma_minalign-instead-of-arch_kmalloc_minalign.patch
drivers-usb-use-arch_dma_minalign-instead-of-arch_kmalloc_minalign.patch
drivers-spi-use-arch_dma_minalign-instead-of-arch_kmalloc_minalign.patch
dm-crypt-use-arch_dma_minalign-instead-of-arch_kmalloc_minalign.patch
iio-core-use-arch_dma_minalign-instead-of-arch_kmalloc_minalign.patch
arm64-allow-kmalloc-caches-aligned-to-the-smaller-cache_line_size.patch
dma-mapping-force-bouncing-if-the-kmalloc-size-is-not-cache-line-aligned.patch
iommu-dma-force-bouncing-if-the-size-is-not-cacheline-aligned.patch
mm-slab-reduce-the-kmalloc-minimum-alignment-if-dma-bouncing-possible.patch
arm64-enable-arch_want_kmalloc_dma_bounce-for-arm64.patch