slub: Do not use 192 byte sized cache if minimum alignment is 128 byte (41d54d3b) · Commits · 戴 / test

include/linux/slub_def.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -137,10 +137,12 @@ static __always_inline int kmalloc_index(size_t size)
		if (size <= KMALLOC_MIN_SIZE)
		return KMALLOC_SHIFT_LOW;

		#if KMALLOC_MIN_SIZE <= 64
		if (size > 64 && size <= 96)
		return 1;
		if (size > 128 && size <= 192)
		return 2;
		#endif
		if (size <= 8) return 3;
		if (size <= 16) return 4;
		if (size <= 32) return 5;

+10 −2

Original line number	Diff line number	Diff line
		@@ -2995,8 +2995,6 @@ void __init kmem_cache_init(void)
		create_kmalloc_cache(&kmalloc_caches[1],
		"kmalloc-96", 96, GFP_KERNEL);
		caches++;
		}
		if (KMALLOC_MIN_SIZE <= 128) {
		create_kmalloc_cache(&kmalloc_caches[2],
		"kmalloc-192", 192, GFP_KERNEL);
		caches++;
		@@ -3026,6 +3024,16 @@ void __init kmem_cache_init(void)
		for (i = 8; i < KMALLOC_MIN_SIZE; i += 8)
		size_index[(i - 1) / 8] = KMALLOC_SHIFT_LOW;

		if (KMALLOC_MIN_SIZE == 128) {
		/*
		* The 192 byte sized cache is not used if the alignment
		* is 128 byte. Redirect kmalloc to use the 256 byte cache
		* instead.
		*/
		for (i = 128 + 8; i <= 192; i += 8)
		size_index[(i - 1) / 8] = 8;
		}

		slab_state = UP;

		/* Provide the correct kmalloc names now that the caches are up */