From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Date: Tue, 29 Aug 2006 20:19:36 +0000 Subject: [RFC][PATCH 03/10] actual generic PAGE_SIZE infrastructure Message-Id: <20060829201936.2C7D5100@localhost.localdomain> List-Id: References: <20060829201934.47E63D1F@localhost.localdomain> In-Reply-To: <20060829201934.47E63D1F@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-mm@kvack.org Cc: linux-ia64@vger.kernel.org, rdunlap@xenotime.net, lethal@linux-sh.org, Dave Hansen * Add _ALIGN_UP() which we'll use now and _ALIGN_DOWN(), just for parity. * Define ASM_CONST() macro to help using constants in both assembly and C code. Several architectures have some form of this, and they will be consolidated around this one. * Actually create PAGE_SHIFT and PAGE_SIZE macros * For now, require that architectures enable GENERIC_PAGE_SIZE in order to get this new code. This option will be removed by the last patch in the series, and makes the series bisect-safe. * Note that this moves the compiler.h define outside of the #ifdef __KERNEL__, but that's OK because it has its own. Signed-off-by: Dave Hansen --- threadalloc-dave/include/linux/align.h | 7 ++++ threadalloc-dave/include/asm-generic/page.h | 31 +++++++++++++++++++-- threadalloc-dave/mm/Kconfig | 41 ++++++++++++++++++++++++++++ 3 files changed, 75 insertions(+), 4 deletions(-) diff -puN include/linux/align.h~generic-PAGE_SIZE-infrastructure include/linux/align.h --- threadalloc/include/linux/align.h~generic-PAGE_SIZE-infrastructure 2006-08-29 13:14:50.000000000 -0700 +++ threadalloc-dave/include/linux/align.h 2006-08-29 13:14:51.000000000 -0700 @@ -6,12 +6,17 @@ * dependencies, and can be used safely from any other header. */ +/* align addr on a size boundary - adjust address up/down if needed */ +#define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1))) +#define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1))) + /* * ALIGN is special. There's a linkage.h as well that * has a quite different meaning. */ #ifndef __ASSEMBLY__ -#define ALIGN(x,a) (((x)+(a)-1)&~((a)-1)) +/* align addr on a size boundary - adjust address up if needed */ +#define ALIGN(addr,size) _ALIGN_UP(addr,size) #endif #endif /* _LINUX_ALIGN_H */ diff -puN include/asm-generic/page.h~generic-PAGE_SIZE-infrastructure include/asm-generic/page.h --- threadalloc/include/asm-generic/page.h~generic-PAGE_SIZE-infrastructure 2006-08-29 13:14:50.000000000 -0700 +++ threadalloc-dave/include/asm-generic/page.h 2006-08-29 13:14:51.000000000 -0700 @@ -1,11 +1,36 @@ #ifndef _ASM_GENERIC_PAGE_H #define _ASM_GENERIC_PAGE_H +#include +#include + #ifdef __KERNEL__ -#ifndef __ASSEMBLY__ -#include +#ifdef __ASSEMBLY__ +#define ASM_CONST(x) x +#else +#define __ASM_CONST(x) x##UL +#define ASM_CONST(x) __ASM_CONST(x) +#endif + +#ifdef CONFIG_ARCH_GENERIC_PAGE_SIZE + +#define PAGE_SHIFT CONFIG_PAGE_SHIFT +#define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) + +/* + * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we + * assign PAGE_MASK to a larger type it gets extended the way we want + * (i.e. with 1s in the high bits) + */ +#define PAGE_MASK (~((1 << PAGE_SHIFT) - 1)) +/* to align the pointer to the (next) page boundary */ +#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE) + +#endif /* CONFIG_ARCH_GENERIC_PAGE_SIZE */ + +#ifndef __ASSEMBLY__ #ifndef CONFIG_ARCH_HAVE_GET_ORDER /* Pure 2^n version of get_order */ static __inline__ __attribute_const__ int get_order(unsigned long size) @@ -22,7 +47,7 @@ static __inline__ __attribute_const__ in } #endif /* CONFIG_ARCH_HAVE_GET_ORDER */ -#endif /* __ASSEMBLY__ */ +#endif /* __ASSEMBLY__ */ #endif /* __KERNEL__ */ #endif /* _ASM_GENERIC_PAGE_H */ diff -puN mm/Kconfig~generic-PAGE_SIZE-infrastructure mm/Kconfig --- threadalloc/mm/Kconfig~generic-PAGE_SIZE-infrastructure 2006-08-29 13:14:50.000000000 -0700 +++ threadalloc-dave/mm/Kconfig 2006-08-29 13:14:51.000000000 -0700 @@ -2,6 +2,47 @@ config ARCH_HAVE_GET_ORDER def_bool y depends on IA64 || PPC32 || XTENSA +choice + prompt "Kernel Page Size" + depends on ARCH_GENERIC_PAGE_SIZE +config PAGE_SIZE_4KB + bool "4KB" + help + This lets you select the page size of the kernel. For best + performance, a page size of larger than 4k is recommended. For best + 32-bit compatibility on 64-bit architectures, a page size of 4KB + should be selected (although most binaries work perfectly fine with + a larger page size). + + 4KB For best 32-bit compatibility + 8KB-64KB Better performace + above 64KB For kernel hackers only + + If you don't know what to do, choose 4KB, or simply leave this + option alone. A sane default has already been selected for your + architecture. +config PAGE_SIZE_8KB + bool "8KB" +config PAGE_SIZE_16KB + bool "16KB" +config PAGE_SIZE_64KB + bool "64KB" +config PAGE_SIZE_512KB + bool "512KB" +config PAGE_SIZE_4MB + bool "4MB" +endchoice + +config PAGE_SHIFT + int + depends on ARCH_GENERIC_PAGE_SIZE + default "13" if PAGE_SIZE_8KB + default "14" if PAGE_SIZE_16KB + default "16" if PAGE_SIZE_64KB + default "19" if PAGE_SIZE_512KB + default "22" if PAGE_SIZE_4MB + default "12" + config SELECT_MEMORY_MODEL def_bool y depends on EXPERIMENTAL || ARCH_SELECT_MEMORY_MODEL _