[IA64] Add __read_mostly support for IA64

sparc64, i386 and x86_64 have support for a special data section dedicated to rarely updated data that is frequently read. The section was created to avoid false sharing of those rarely read data with frequently written kernel data. This patch creates such a data section for ia64 and will group rarely written data into this section.

Christoph Lameter committed 20 years ago

Commit dc86e881 parent d5bf3162 files · +4 −1Browse files

Unified · Split

2 files

arch/ia64/kernel/vmlinux.lds.S +3 −0
include/linux/cache.h +1 −1

arch/ia64/kernel/vmlinux.lds.S+3−0

@@ -177,6 +177,9 @@ SECTIONS · 176 unmodified lines
177	}	177	}
178	. = ALIGN(PAGE_SIZE); /* make sure the gate page doesn't expose kernel data */	178	. = ALIGN(PAGE_SIZE); /* make sure the gate page doesn't expose kernel data */
179		179
		180	.data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET)
		181	{ *(.data.read_mostly) }
		182
180	.data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET)	183	.data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET)
181	{ *(.data.cacheline_aligned) }	184	{ *(.data.cacheline_aligned) }
182		185

include/linux/cache.h+1−1

@@ -13,7 +13,7 @@ · 12 unmodified lines
13	#define SMP_CACHE_BYTES L1_CACHE_BYTES	13	#define SMP_CACHE_BYTES L1_CACHE_BYTES
14	#endif	14	#endif
15		15
16	#if defined(CONFIG_X86) \|\| defined(CONFIG_SPARC64)	16	#if defined(CONFIG_X86) \|\| defined(CONFIG_SPARC64) \|\| defined(CONFIG_IA64)
17	#define __read_mostly __attribute__((__section__(".data.read_mostly")))	17	#define __read_mostly __attribute__((__section__(".data.read_mostly")))
18	#else	18	#else
19	#define __read_mostly	19	#define __read_mostly