um: allow using glibc string functions instead of generics

Message ID	20201110163034.22963-1-anton.ivanov@cambridgegreys.com
State	Superseded
Headers	show Return-Path: <linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org> From: anton.ivanov@cambridgegreys.com To: linux-um@lists.infradead.org Subject: [PATCH] um: allow using glibc string functions instead of generics Date: Tue, 10 Nov 2020 16:30:34 +0000 Message-Id: <20201110163034.22963-1-anton.ivanov@cambridgegreys.com> MIME-Version: 1.0 summary: Content analysis details: (0.4 points) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 SPF_NONE SPF: sender does not publish an SPF Record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.4 KHOP_HELO_FCRDNS Relay HELO differs from its IP's reverse DNS Precedence: list Cc: richard@nod.at, Anton Ivanov <anton.ivanov@cambridgegreys.com> Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" <linux-um-bounces@lists.infradead.org> Errors-To: linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org
Series	um: allow using glibc string functions instead of generics \| expand um: allow using glibc string functions instead of generics

diff --git a/arch/um/Kconfig b/arch/um/Kconfig index 4b799fad8b48..961cf3af3ff0 100644 --- a/arch/um/Kconfig +++ b/arch/um/Kconfig @@ -189,6 +189,17 @@ config UML_TIME_TRAVEL_SUPPORT It is safe to say Y, but you probably don't need this. +config UML_USE_HOST_STRINGS + bool + default y + prompt "Use glibc strings and memory functions" + help + UML runs as a normal userspace process. As a result it can use + the optimized strcpy, memcpy, etc from glibc instead of the + kernel generic equivalents. This provides some minimal speedup + in the 1% or so range for most applications. It also results in + a smaller executable. + endmenu source "arch/um/drivers/Kconfig" diff --git a/arch/um/include/asm/string.h b/arch/um/include/asm/string.h new file mode 100644 index 000000000000..1fba8d59afe5 --- /dev/null +++ b/arch/um/include/asm/string.h @@ -0,0 +1,72 @@ +#ifndef __ASM_UM_STRING_H +#define __ASM_UM_STRING_H + +#ifdef CONFIG_UML_USE_HOST_STRINGS + +/* UML saves and restores registers when going to/from + * userspace. This allows the use of normal userspace + * functions for strings with all relevant glibc processor + * optimizations + */ + +#include <os_string.h> + +#define __HAVE_ARCH_STRCPY + +#define strcpy(dest, src) os_strcpy(dest, src); + +#define __HAVE_ARCH_STRNCPY + +#define strncpy(dest, src, count) os_strncpy(dest, src, count) + +#define __HAVE_ARCH_STRCAT + +#define strcat(dest, src) os_strcat(dest, src) + +#define __HAVE_ARCH_STRNCAT + +#define strncat(dest, src, count) os_strncat(dest, src, count) + +#define __HAVE_ARCH_STRCMP + +#define strcmp(cs, ct) os_strcmp(cs, ct) + +#define __HAVE_ARCH_STRNCMP + +#define strncmp(cs, ct, count) os_strncmp(cs, ct, count) + +#define __HAVE_ARCH_STRCHR + +#define strchr(s, c) os_strchr(s, c) + +#define __HAVE_ARCH_STRLEN + +#define strlen(s) os_strlen(s) + +#define __HAVE_ARCH_MEMCPY + +#define memcpy(dst, src, n) os_memcpy(dst, src, n) + +#define __HAVE_ARCH_MEMMOVE + +#define memmove(dest, src, n) os_memmove(dest, src, n) + +#define __HAVE_ARCH_MEMCHR + +#define memchr(cs, c, count) os_memchr(cs, c, count) + +#define __HAVE_ARCH_STRNLEN + +#define strnlen(s, count) os_strnlen(s, count) + +#define __HAVE_ARCH_STRSTR + +#define strstr(cs, ct) os_strstr(cs, ct) + +#define __HAVE_ARCH_MEMSET + +#define memset(dst, c, n) os_memset(dst, c, n) + +#endif + +#endif /* __ASM_GENERIC_STRING_H */ diff --git a/arch/um/include/shared/os_string.h b/arch/um/include/shared/os_string.h new file mode 100644 index 000000000000..b9662f622e77 --- /dev/null +++ b/arch/um/include/shared/os_string.h @@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk}) + * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de) + * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + */ + +#ifndef __OS_STRING_H__ +#define __OS_STRING_H__ + +#include <stddef.h> + +/* string.c */ + +extern char *os_strcpy(char *dest, const char *src); +extern char *os_strncpy(char *dest, const char *src, size_t count); +extern char *os_strcat(char *dest, const char *src); +extern char *os_strncat(char *dest, const char *src, size_t count); +extern int os_strcmp(const char *cs, const char *ct); +extern int os_strncmp(const char *cs, const char *ct, size_t count); +extern char *os_strchr(const char *s, int c); +extern size_t os_strlen(const char *s); +extern void *os_memcpy(void *dest, const void *src, size_t n); +extern void *os_memmove(void *dest, const void *src, size_t n); +extern void *os_memchr(const void *cs, int c, size_t count); +extern size_t os_strnlen(const char *s, size_t count); +extern char *os_strstr(const char *cs, const char *ct); +extern void *os_memset(void *s, int c, size_t n); + +#endif diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile index 839915b8c31c..f117f2514191 100644 --- a/arch/um/os-Linux/Makefile +++ b/arch/um/os-Linux/Makefile @@ -8,12 +8,12 @@ KCOV_INSTRUMENT := n obj-y = execvp.o file.o helper.o irq.o main.o mem.o process.o \ registers.o sigio.o signal.o start_up.o time.o tty.o \ - umid.o user_syms.o util.o drivers/ skas/ + umid.o user_syms.o util.o string.o drivers/ skas/ obj-$(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA) += elf_aux.o USER_OBJS := $(user-objs-y) elf_aux.o execvp.o file.o helper.o irq.o \ main.o mem.o process.o registers.o sigio.o signal.o start_up.o time.o \ - tty.o umid.o util.o + tty.o umid.o util.o string.o include arch/um/scripts/Makefile.rules diff --git a/arch/um/os-Linux/string.c b/arch/um/os-Linux/string.c new file mode 100644 index 000000000000..abc76e2aecb3 --- /dev/null +++ b/arch/um/os-Linux/string.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + */ + +#include <stddef.h> +#include <unistd.h> +#include <string.h> +#include <os_string.h> + +inline char *os_strcpy(char *dest, const char *src) +{ + return strcpy(dest, src); +} + +inline char *os_strncpy(char *dest, const char *src, size_t count) +{ + return strncpy(dest, src, count); +} + +inline char *os_strcat(char *dest, const char *src) +{ + return strcat(dest, src); +} +inline char *os_strncat(char *dest, const char *src, size_t count) +{ + return strncat(dest, src, count); +} + +inline int os_strcmp(const char *cs, const char *ct) +{ + return strcmp(cs, ct); +} + +inline int os_strncmp(const char *cs, const char *ct, size_t count) +{ + return strncmp(cs, ct, count); +} + +inline char *os_strchr(const char *s, int c) +{ + return strchr(s, c); +} +inline size_t os_strlen(const char *s) +{ + return strlen(s); +} + +inline void *os_memcpy(void *dest, const void *src, size_t n) +{ + return memcpy(dest, src, n); +} + +inline void *os_memmove(void *dest, const void *src, size_t n) +{ + return memmove(dest, src, n); +} + +inline void *os_memchr(const void *cs, int c, size_t count) +{ + return memchr(cs, c, count); +} + +inline size_t os_strnlen(const char *s, size_t count) +{ + return strnlen(s, count); +} + +inline char *os_strstr(const char *cs, const char *ct) +{ + return strstr(cs, ct); +} + +inline void *os_memset(void *s, int c, size_t n) +{ + return memset(s, c, n); +} +

um: allow using glibc string functions instead of generics

Commit Message

Comments

Patch