1*b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */ 21da177e4SLinus Torvalds #ifndef __LINUX_CACHE_H 31da177e4SLinus Torvalds #define __LINUX_CACHE_H 41da177e4SLinus Torvalds 5c28aa1f0SJoe Perches #include <uapi/linux/kernel.h> 61da177e4SLinus Torvalds #include <asm/cache.h> 71da177e4SLinus Torvalds 81da177e4SLinus Torvalds #ifndef L1_CACHE_ALIGN 9c28aa1f0SJoe Perches #define L1_CACHE_ALIGN(x) __ALIGN_KERNEL(x, L1_CACHE_BYTES) 101da177e4SLinus Torvalds #endif 111da177e4SLinus Torvalds 121da177e4SLinus Torvalds #ifndef SMP_CACHE_BYTES 131da177e4SLinus Torvalds #define SMP_CACHE_BYTES L1_CACHE_BYTES 141da177e4SLinus Torvalds #endif 151da177e4SLinus Torvalds 16c74ba8b3SKees Cook /* 17c74ba8b3SKees Cook * __read_mostly is used to keep rarely changing variables out of frequently 18c74ba8b3SKees Cook * updated cachelines. If an architecture doesn't support it, ignore the 19c74ba8b3SKees Cook * hint. 20c74ba8b3SKees Cook */ 21804f1594SKyle McMartin #ifndef __read_mostly 226c036527SChristoph Lameter #define __read_mostly 236c036527SChristoph Lameter #endif 246c036527SChristoph Lameter 25c74ba8b3SKees Cook /* 26c74ba8b3SKees Cook * __ro_after_init is used to mark things that are read-only after init (i.e. 27c74ba8b3SKees Cook * after mark_rodata_ro() has been called). These are effectively read-only, 28c74ba8b3SKees Cook * but may get written to during init, so can't live in .rodata (via "const"). 29c74ba8b3SKees Cook */ 30c74ba8b3SKees Cook #ifndef __ro_after_init 31c74ba8b3SKees Cook #define __ro_after_init __attribute__((__section__(".data..ro_after_init"))) 32c74ba8b3SKees Cook #endif 33c74ba8b3SKees Cook 341da177e4SLinus Torvalds #ifndef ____cacheline_aligned 351da177e4SLinus Torvalds #define ____cacheline_aligned __attribute__((__aligned__(SMP_CACHE_BYTES))) 361da177e4SLinus Torvalds #endif 371da177e4SLinus Torvalds 381da177e4SLinus Torvalds #ifndef ____cacheline_aligned_in_smp 391da177e4SLinus Torvalds #ifdef CONFIG_SMP 401da177e4SLinus Torvalds #define ____cacheline_aligned_in_smp ____cacheline_aligned 411da177e4SLinus Torvalds #else 421da177e4SLinus Torvalds #define ____cacheline_aligned_in_smp 431da177e4SLinus Torvalds #endif /* CONFIG_SMP */ 441da177e4SLinus Torvalds #endif 451da177e4SLinus Torvalds 461da177e4SLinus Torvalds #ifndef __cacheline_aligned 471da177e4SLinus Torvalds #define __cacheline_aligned \ 481da177e4SLinus Torvalds __attribute__((__aligned__(SMP_CACHE_BYTES), \ 494af57b78STim Abbott __section__(".data..cacheline_aligned"))) 501da177e4SLinus Torvalds #endif /* __cacheline_aligned */ 511da177e4SLinus Torvalds 521da177e4SLinus Torvalds #ifndef __cacheline_aligned_in_smp 531da177e4SLinus Torvalds #ifdef CONFIG_SMP 541da177e4SLinus Torvalds #define __cacheline_aligned_in_smp __cacheline_aligned 551da177e4SLinus Torvalds #else 561da177e4SLinus Torvalds #define __cacheline_aligned_in_smp 571da177e4SLinus Torvalds #endif /* CONFIG_SMP */ 581da177e4SLinus Torvalds #endif 591da177e4SLinus Torvalds 6022fc6eccSRavikiran G Thirumalai /* 6122fc6eccSRavikiran G Thirumalai * The maximum alignment needed for some critical structures 6222fc6eccSRavikiran G Thirumalai * These could be inter-node cacheline sizes/L3 cacheline 6322fc6eccSRavikiran G Thirumalai * size etc. Define this in asm/cache.h for your arch 6422fc6eccSRavikiran G Thirumalai */ 6522fc6eccSRavikiran G Thirumalai #ifndef INTERNODE_CACHE_SHIFT 6622fc6eccSRavikiran G Thirumalai #define INTERNODE_CACHE_SHIFT L1_CACHE_SHIFT 6722fc6eccSRavikiran G Thirumalai #endif 6822fc6eccSRavikiran G Thirumalai 6922fc6eccSRavikiran G Thirumalai #if !defined(____cacheline_internodealigned_in_smp) 701da177e4SLinus Torvalds #if defined(CONFIG_SMP) 7122fc6eccSRavikiran G Thirumalai #define ____cacheline_internodealigned_in_smp \ 7222fc6eccSRavikiran G Thirumalai __attribute__((__aligned__(1 << (INTERNODE_CACHE_SHIFT)))) 731da177e4SLinus Torvalds #else 7422fc6eccSRavikiran G Thirumalai #define ____cacheline_internodealigned_in_smp 751da177e4SLinus Torvalds #endif 761da177e4SLinus Torvalds #endif 771da177e4SLinus Torvalds 781b27d05bSPekka Enberg #ifndef CONFIG_ARCH_HAS_CACHE_LINE_SIZE 791b27d05bSPekka Enberg #define cache_line_size() L1_CACHE_BYTES 801b27d05bSPekka Enberg #endif 811b27d05bSPekka Enberg 821da177e4SLinus Torvalds #endif /* __LINUX_CACHE_H */ 83