From 42daba316557e597a90a730f61c762602b7f0e0c Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Tue, 16 Oct 2007 01:26:47 -0700 Subject: [PATCH] uml: stop saving process FP state Throw out a lot of code dealing with saving and restoring floating-point state. In skas mode, where processes run in a restoring floating-point state on kernel entry and exit is pointless. This eliminates most of arch/um/os-Linux/sys-{i386,x86_64}/registers.c. Most of what remained is now arch-indpendent, and can be moved up to arch/um/os-Linux/registers.c. Both arches need the jmp_buf accessor get_thread_reg, and i386 needs {save,restore}_fp_regs because it cheats during sigreturn by getting the fp state using ptrace rather than copying it out of the process sigcontext. After this, it turns out that arch/um/include/skas/mode-skas.h is almost completely unneeded. The declarations in it are variables which either don't exist or which don't have global scope. The one exception is kill_off_processes_skas. If that's removed, this header can be deleted. This uncovered a bug in user.h, which wasn't correctly making sure that a size_t definition was available to both userspace and kernelspace files. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/include/os.h | 2 + arch/um/include/registers.h | 2 +- arch/um/include/skas/mode-skas.h | 9 +- arch/um/include/sysdep-i386/ptrace.h | 11 --- arch/um/include/user.h | 8 +- arch/um/os-Linux/Makefile | 8 +- arch/um/os-Linux/registers.c | 54 ++++++++++++ arch/um/os-Linux/skas/mem.c | 2 +- arch/um/os-Linux/skas/process.c | 8 +- arch/um/os-Linux/sys-i386/registers.c | 108 +----------------------- arch/um/os-Linux/sys-x86_64/Makefile | 2 +- arch/um/os-Linux/sys-x86_64/registers.c | 75 +--------------- 12 files changed, 74 insertions(+), 215 deletions(-) create mode 100644 arch/um/os-Linux/registers.c diff --git a/arch/um/include/os.h b/arch/um/include/os.h index bb6b7d9e188..c0803e67fc6 100644 --- a/arch/um/include/os.h +++ b/arch/um/include/os.h @@ -307,6 +307,8 @@ extern int protect(struct mm_id * mm_idp, unsigned long addr, extern int is_skas_winch(int pid, int fd, void *data); extern int start_userspace(unsigned long stub_stack); extern int copy_context_skas0(unsigned long stack, int pid); +extern void save_registers(int pid, union uml_pt_regs *regs); +extern void restore_registers(int pid, union uml_pt_regs *regs); extern void userspace(union uml_pt_regs *regs); extern void map_stub_pages(int fd, unsigned long code, unsigned long data, unsigned long stack); diff --git a/arch/um/include/registers.h b/arch/um/include/registers.h index f845b3629a6..b7d2c4e2c61 100644 --- a/arch/um/include/registers.h +++ b/arch/um/include/registers.h @@ -15,7 +15,7 @@ extern int restore_fp_registers(int pid, unsigned long *fp_regs); extern void save_registers(int pid, union uml_pt_regs *regs); extern void restore_registers(int pid, union uml_pt_regs *regs); extern void init_registers(int pid); -extern void get_safe_registers(unsigned long * regs, unsigned long * fp_regs); +extern void get_safe_registers(unsigned long *regs); extern unsigned long get_thread_reg(int reg, jmp_buf *buf); #endif diff --git a/arch/um/include/skas/mode-skas.h b/arch/um/include/skas/mode-skas.h index 8bc6916bbbb..e065feb000d 100644 --- a/arch/um/include/skas/mode-skas.h +++ b/arch/um/include/skas/mode-skas.h @@ -1,18 +1,11 @@ /* - * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) + * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com) * Licensed under the GPL */ #ifndef __MODE_SKAS_H__ #define __MODE_SKAS_H__ -#include - -extern unsigned long exec_regs[]; -extern unsigned long exec_fp_regs[]; -extern unsigned long exec_fpx_regs[]; -extern int have_fpx_regs; - extern void kill_off_processes_skas(void); #endif diff --git a/arch/um/include/sysdep-i386/ptrace.h b/arch/um/include/sysdep-i386/ptrace.h index 52b398bcafc..b45a72feb08 100644 --- a/arch/um/include/sysdep-i386/ptrace.h +++ b/arch/um/include/sysdep-i386/ptrace.h @@ -219,14 +219,3 @@ struct syscall_args { CHOOSE_MODE((&(r)->tt.faultinfo), (&(r)->skas.faultinfo)) #endif - -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ diff --git a/arch/um/include/user.h b/arch/um/include/user.h index d380e6d91a9..99033ff28a7 100644 --- a/arch/um/include/user.h +++ b/arch/um/include/user.h @@ -14,10 +14,12 @@ */ #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) -/* - * This will provide the size_t definition in both kernel and userspace builds - */ +/* This is to get size_t */ +#ifdef __KERNEL__ #include +#else +#include +#endif extern void panic(const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile index 2f8c7946401..f1bb58fe320 100644 --- a/arch/um/os-Linux/Makefile +++ b/arch/um/os-Linux/Makefile @@ -4,8 +4,8 @@ # obj-y = aio.o elf_aux.o execvp.o file.o helper.o irq.o main.o mem.o process.o \ - sigio.o signal.o start_up.o time.o trap.o tty.o uaccess.o umid.o tls.o \ - user_syms.o util.o drivers/ sys-$(SUBARCH)/ + registers.o sigio.o signal.o start_up.o time.o trap.o tty.o uaccess.o \ + umid.o tls.o user_syms.o util.o drivers/ sys-$(SUBARCH)/ obj-$(CONFIG_MODE_SKAS) += skas/ @@ -16,8 +16,8 @@ obj-$(CONFIG_TTY_LOG) += tty_log.o user-objs-$(CONFIG_TTY_LOG) += tty_log.o USER_OBJS := $(user-objs-y) aio.o elf_aux.o execvp.o file.o helper.o irq.o \ - main.o mem.o process.o sigio.o signal.o start_up.o time.o trap.o tty.o \ - tls.o uaccess.o umid.o util.o + main.o mem.o process.o registers.o sigio.o signal.o start_up.o time.o \ + trap.o tty.o tls.o uaccess.o umid.o util.o CFLAGS_user_syms.o += -DSUBARCH_$(SUBARCH) diff --git a/arch/um/os-Linux/registers.c b/arch/um/os-Linux/registers.c new file mode 100644 index 00000000000..9dc3fad9ea2 --- /dev/null +++ b/arch/um/os-Linux/registers.c @@ -0,0 +1,54 @@ +/* + * Copyright (C) 2004 PathScale, Inc + * Licensed under the GPL + */ + +#include +#include +#include +#include "user.h" +#include "sysdep/ptrace.h" + +/* This is set once at boot time and not changed thereafter */ + +static unsigned long exec_regs[MAX_REG_NR]; + +void init_thread_registers(union uml_pt_regs *to) +{ + memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs)); +} + +void save_registers(int pid, union uml_pt_regs *regs) +{ + int err; + + err = ptrace(PTRACE_GETREGS, pid, 0, regs->skas.regs); + if(err < 0) + panic("save_registers - saving registers failed, errno = %d\n", + errno); +} + +void restore_registers(int pid, union uml_pt_regs *regs) +{ + int err; + + err = ptrace(PTRACE_SETREGS, pid, 0, regs->skas.regs); + if(err < 0) + panic("restore_registers - saving registers failed, " + "errno = %d\n", errno); +} + +void init_registers(int pid) +{ + int err; + + err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs); + if(err) + panic("check_ptrace : PTRACE_GETREGS failed, errno = %d", + errno); +} + +void get_safe_registers(unsigned long *regs) +{ + memcpy(regs, exec_regs, sizeof(exec_regs)); +} diff --git a/arch/um/os-Linux/skas/mem.c b/arch/um/os-Linux/skas/mem.c index 9fbf210ebfb..383052baa16 100644 --- a/arch/um/os-Linux/skas/mem.c +++ b/arch/um/os-Linux/skas/mem.c @@ -44,7 +44,7 @@ static unsigned long syscall_regs[MAX_REG_NR]; static int __init init_syscall_regs(void) { - get_safe_registers(syscall_regs, NULL); + get_safe_registers(syscall_regs); syscall_regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE + ((unsigned long) &batch_syscall_stub - (unsigned long) &__syscall_stub_start); diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c index ba9af8d6205..db020d21f13 100644 --- a/arch/um/os-Linux/skas/process.c +++ b/arch/um/os-Linux/skas/process.c @@ -357,11 +357,10 @@ void userspace(union uml_pt_regs *regs) } static unsigned long thread_regs[MAX_REG_NR]; -static unsigned long thread_fp_regs[HOST_FP_SIZE]; static int __init init_thread_regs(void) { - get_safe_registers(thread_regs, thread_fp_regs); + get_safe_registers(thread_regs); /* Set parent's instruction pointer to start of clone-stub */ thread_regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE + (unsigned long) stub_clone_handler - @@ -398,11 +397,6 @@ int copy_context_skas0(unsigned long new_stack, int pid) panic("copy_context_skas0 : PTRACE_SETREGS failed, " "pid = %d, errno = %d\n", pid, -err); - err = ptrace_setfpregs(pid, thread_fp_regs); - if(err < 0) - panic("copy_context_skas0 : PTRACE_SETFPREGS failed, " - "pid = %d, errno = %d\n", pid, -err); - /* set a well known return code for detection of child write failure */ child_data->err = 12345678; diff --git a/arch/um/os-Linux/sys-i386/registers.c b/arch/um/os-Linux/sys-i386/registers.c index 84b44f9cd42..f171204caa4 100644 --- a/arch/um/os-Linux/sys-i386/registers.c +++ b/arch/um/os-Linux/sys-i386/registers.c @@ -4,30 +4,10 @@ */ #include -#include -#include "sysdep/ptrace_user.h" -#include "sysdep/ptrace.h" -#include "uml-config.h" -#include "skas_ptregs.h" -#include "registers.h" +#include #include "longjmp.h" #include "user.h" -/* These are set once at boot time and not changed thereafter */ - -static unsigned long exec_regs[MAX_REG_NR]; -static unsigned long exec_fp_regs[HOST_FP_SIZE]; -static unsigned long exec_fpx_regs[HOST_XFP_SIZE]; -static int have_fpx_regs = 1; - -void init_thread_registers(union uml_pt_regs *to) -{ - memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs)); - memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp)); - if(have_fpx_regs) - memcpy(to->skas.xfp, exec_fpx_regs, sizeof(to->skas.xfp)); -} - /* XXX These need to use [GS]ETFPXREGS and copy_sc_{to,from}_user_skas needs * to pass in a sufficiently large buffer */ @@ -45,92 +25,6 @@ int restore_fp_registers(int pid, unsigned long *fp_regs) return 0; } -static int move_registers(int pid, int int_op, union uml_pt_regs *regs, - int fp_op, unsigned long *fp_regs) -{ - if(ptrace(int_op, pid, 0, regs->skas.regs) < 0) - return -errno; - - if(ptrace(fp_op, pid, 0, fp_regs) < 0) - return -errno; - - return 0; -} - -void save_registers(int pid, union uml_pt_regs *regs) -{ - unsigned long *fp_regs; - int err, fp_op; - - if(have_fpx_regs){ - fp_op = PTRACE_GETFPXREGS; - fp_regs = regs->skas.xfp; - } - else { - fp_op = PTRACE_GETFPREGS; - fp_regs = regs->skas.fp; - } - - err = move_registers(pid, PTRACE_GETREGS, regs, fp_op, fp_regs); - if(err) - panic("save_registers - saving registers failed, errno = %d\n", - -err); -} - -void restore_registers(int pid, union uml_pt_regs *regs) -{ - unsigned long *fp_regs; - int err, fp_op; - - if(have_fpx_regs){ - fp_op = PTRACE_SETFPXREGS; - fp_regs = regs->skas.xfp; - } - else { - fp_op = PTRACE_SETFPREGS; - fp_regs = regs->skas.fp; - } - - err = move_registers(pid, PTRACE_SETREGS, regs, fp_op, fp_regs); - if(err) - panic("restore_registers - saving registers failed, " - "errno = %d\n", -err); -} - -void init_registers(int pid) -{ - int err; - - memset(exec_regs, 0, sizeof(exec_regs)); - err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs); - if(err) - panic("check_ptrace : PTRACE_GETREGS failed, errno = %d", - errno); - - errno = 0; - err = ptrace(PTRACE_GETFPXREGS, pid, 0, exec_fpx_regs); - if(!err) - return; - if(errno != EIO) - panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d", - errno); - - have_fpx_regs = 0; - - err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs); - if(err) - panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d", - errno); -} - -void get_safe_registers(unsigned long *regs, unsigned long *fp_regs) -{ - memcpy(regs, exec_regs, sizeof(exec_regs)); - if(fp_regs != NULL) - memcpy(fp_regs, exec_fp_regs, - HOST_FP_SIZE * sizeof(unsigned long)); -} - unsigned long get_thread_reg(int reg, jmp_buf *buf) { switch(reg){ diff --git a/arch/um/os-Linux/sys-x86_64/Makefile b/arch/um/os-Linux/sys-x86_64/Makefile index 7955e061a67..eac8c0db300 100644 --- a/arch/um/os-Linux/sys-x86_64/Makefile +++ b/arch/um/os-Linux/sys-x86_64/Makefile @@ -1,5 +1,5 @@ # -# Copyright (C) 2000 Jeff Dike (jdike@karaya.com) +# Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) # Licensed under the GPL # diff --git a/arch/um/os-Linux/sys-x86_64/registers.c b/arch/um/os-Linux/sys-x86_64/registers.c index 9467315b805..9bfa789992d 100644 --- a/arch/um/os-Linux/sys-x86_64/registers.c +++ b/arch/um/os-Linux/sys-x86_64/registers.c @@ -1,23 +1,15 @@ /* - * Copyright (C) 2004 PathScale, Inc + * Copyright (C) 2006-2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) * Licensed under the GPL */ #include #include -#include -#include "ptrace_user.h" -#include "uml-config.h" -#include "skas_ptregs.h" -#include "registers.h" +#define __FRAME_OFFSETS +#include #include "longjmp.h" #include "user.h" -/* These are set once at boot time and not changed thereafter */ - -static unsigned long exec_regs[MAX_REG_NR]; -static unsigned long exec_fp_regs[HOST_FP_SIZE]; - int save_fp_registers(int pid, unsigned long *fp_regs) { if(ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0) @@ -32,67 +24,6 @@ int restore_fp_registers(int pid, unsigned long *fp_regs) return 0; } -void init_thread_registers(union uml_pt_regs *to) -{ - memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs)); - memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp)); -} - -static int move_registers(int pid, int int_op, int fp_op, - union uml_pt_regs *regs) -{ - if(ptrace(int_op, pid, 0, regs->skas.regs) < 0) - return -errno; - - if(ptrace(fp_op, pid, 0, regs->skas.fp) < 0) - return -errno; - - return 0; -} - -void save_registers(int pid, union uml_pt_regs *regs) -{ - int err; - - err = move_registers(pid, PTRACE_GETREGS, PTRACE_GETFPREGS, regs); - if(err) - panic("save_registers - saving registers failed, errno = %d\n", - -err); -} - -void restore_registers(int pid, union uml_pt_regs *regs) -{ - int err; - - err = move_registers(pid, PTRACE_SETREGS, PTRACE_SETFPREGS, regs); - if(err) - panic("restore_registers - saving registers failed, " - "errno = %d\n", -err); -} - -void init_registers(int pid) -{ - int err; - - err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs); - if(err) - panic("check_ptrace : PTRACE_GETREGS failed, errno = %d", - errno); - - err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs); - if(err) - panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d", - errno); -} - -void get_safe_registers(unsigned long *regs, unsigned long *fp_regs) -{ - memcpy(regs, exec_regs, sizeof(exec_regs)); - if(fp_regs != NULL) - memcpy(fp_regs, exec_fp_regs, - HOST_FP_SIZE * sizeof(unsigned long)); -} - unsigned long get_thread_reg(int reg, jmp_buf *buf) { switch(reg){ -- 2.20.1