From ecaf45ee5ce60afe7cc46e91d82c1b0cbda09387 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:29 +0200 Subject: [PATCH] [PATCH] i386: Redo semaphore and rwlock assembly helpers - Move them to a pure assembly file. Previously they were in a C file that only consisted of inline assembly. Doing it in pure assembler is much nicer. - Add a frame.i include with FRAME/ENDFRAME macros to easily add frame pointers to assembly functions - Add dwarf2 annotation to them so that the new dwarf2 unwinder doesn't get stuck on them - Random cleanups Includes feedback from Jan Beulich and a UML build fix from Andrew Morton. Cc: jbeulich@novell.com Cc: jdike@addtoit.com Signed-off-by: Andi Kleen --- arch/i386/kernel/Makefile | 2 +- arch/i386/kernel/semaphore.c | 134 --------------------------- arch/i386/lib/Makefile | 2 +- arch/i386/lib/semaphore.S | 154 +++++++++++++++++++++++++++++++ arch/um/sys-i386/Makefile | 2 +- include/asm-i386/frame.i | 24 +++++ include/asm-um/alternative-asm.i | 6 ++ include/asm-um/frame.i | 6 ++ 8 files changed, 193 insertions(+), 137 deletions(-) delete mode 100644 arch/i386/kernel/semaphore.c create mode 100644 arch/i386/lib/semaphore.S create mode 100644 include/asm-i386/frame.i create mode 100644 include/asm-um/alternative-asm.i create mode 100644 include/asm-um/frame.i diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile index 5427a842e841..dab497472deb 100644 --- a/arch/i386/kernel/Makefile +++ b/arch/i386/kernel/Makefile @@ -4,7 +4,7 @@ extra-y := head.o init_task.o vmlinux.lds -obj-y := process.o semaphore.o signal.o entry.o traps.o irq.o \ +obj-y := process.o signal.o entry.o traps.o irq.o \ ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_i386.o \ pci-dma.o i386_ksyms.o i387.o bootflag.o \ quirks.o i8237.o topology.o alternative.o i8253.o tsc.o diff --git a/arch/i386/kernel/semaphore.c b/arch/i386/kernel/semaphore.c deleted file mode 100644 index 98352c374c76..000000000000 --- a/arch/i386/kernel/semaphore.c +++ /dev/null @@ -1,134 +0,0 @@ -/* - * i386 semaphore implementation. - * - * (C) Copyright 1999 Linus Torvalds - * - * Portions Copyright 1999 Red Hat, Inc. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * rw semaphores implemented November 1999 by Benjamin LaHaise - */ -#include - -/* - * The semaphore operations have a special calling sequence that - * allow us to do a simpler in-line version of them. These routines - * need to convert that sequence back into the C sequence when - * there is contention on the semaphore. - * - * %eax contains the semaphore pointer on entry. Save the C-clobbered - * registers (%eax, %edx and %ecx) except %eax whish is either a return - * value or just clobbered.. - */ -asm( -".section .sched.text\n" -".align 4\n" -".globl __down_failed\n" -"__down_failed:\n\t" -#if defined(CONFIG_FRAME_POINTER) - "pushl %ebp\n\t" - "movl %esp,%ebp\n\t" -#endif - "pushl %edx\n\t" - "pushl %ecx\n\t" - "call __down\n\t" - "popl %ecx\n\t" - "popl %edx\n\t" -#if defined(CONFIG_FRAME_POINTER) - "movl %ebp,%esp\n\t" - "popl %ebp\n\t" -#endif - "ret" -); - -asm( -".section .sched.text\n" -".align 4\n" -".globl __down_failed_interruptible\n" -"__down_failed_interruptible:\n\t" -#if defined(CONFIG_FRAME_POINTER) - "pushl %ebp\n\t" - "movl %esp,%ebp\n\t" -#endif - "pushl %edx\n\t" - "pushl %ecx\n\t" - "call __down_interruptible\n\t" - "popl %ecx\n\t" - "popl %edx\n\t" -#if defined(CONFIG_FRAME_POINTER) - "movl %ebp,%esp\n\t" - "popl %ebp\n\t" -#endif - "ret" -); - -asm( -".section .sched.text\n" -".align 4\n" -".globl __down_failed_trylock\n" -"__down_failed_trylock:\n\t" -#if defined(CONFIG_FRAME_POINTER) - "pushl %ebp\n\t" - "movl %esp,%ebp\n\t" -#endif - "pushl %edx\n\t" - "pushl %ecx\n\t" - "call __down_trylock\n\t" - "popl %ecx\n\t" - "popl %edx\n\t" -#if defined(CONFIG_FRAME_POINTER) - "movl %ebp,%esp\n\t" - "popl %ebp\n\t" -#endif - "ret" -); - -asm( -".section .sched.text\n" -".align 4\n" -".globl __up_wakeup\n" -"__up_wakeup:\n\t" - "pushl %edx\n\t" - "pushl %ecx\n\t" - "call __up\n\t" - "popl %ecx\n\t" - "popl %edx\n\t" - "ret" -); - -/* - * rw spinlock fallbacks - */ -#if defined(CONFIG_SMP) -asm( -".section .sched.text\n" -".align 4\n" -".globl __write_lock_failed\n" -"__write_lock_failed:\n\t" - LOCK_PREFIX "addl $" RW_LOCK_BIAS_STR ",(%eax)\n" -"1: rep; nop\n\t" - "cmpl $" RW_LOCK_BIAS_STR ",(%eax)\n\t" - "jne 1b\n\t" - LOCK_PREFIX "subl $" RW_LOCK_BIAS_STR ",(%eax)\n\t" - "jnz __write_lock_failed\n\t" - "ret" -); - -asm( -".section .sched.text\n" -".align 4\n" -".globl __read_lock_failed\n" -"__read_lock_failed:\n\t" - LOCK_PREFIX "incl (%eax)\n" -"1: rep; nop\n\t" - "cmpl $1,(%eax)\n\t" - "js 1b\n\t" - LOCK_PREFIX "decl (%eax)\n\t" - "js __read_lock_failed\n\t" - "ret" -); -#endif diff --git a/arch/i386/lib/Makefile b/arch/i386/lib/Makefile index 914933e9ec3d..d86a548b8d54 100644 --- a/arch/i386/lib/Makefile +++ b/arch/i386/lib/Makefile @@ -4,6 +4,6 @@ lib-y = checksum.o delay.o usercopy.o getuser.o putuser.o memcpy.o strstr.o \ - bitops.o + bitops.o semaphore.o lib-$(CONFIG_X86_USE_3DNOW) += mmx.o diff --git a/arch/i386/lib/semaphore.S b/arch/i386/lib/semaphore.S new file mode 100644 index 000000000000..e16ff1696390 --- /dev/null +++ b/arch/i386/lib/semaphore.S @@ -0,0 +1,154 @@ +/* + * i386 semaphore implementation. + * + * (C) Copyright 1999 Linus Torvalds + * + * Portions Copyright 1999 Red Hat, Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * rw semaphores implemented November 1999 by Benjamin LaHaise + */ + +#include +#include +#include +#include +#include +#include + +/* + * The semaphore operations have a special calling sequence that + * allow us to do a simpler in-line version of them. These routines + * need to convert that sequence back into the C sequence when + * there is contention on the semaphore. + * + * %eax contains the semaphore pointer on entry. Save the C-clobbered + * registers (%eax, %edx and %ecx) except %eax whish is either a return + * value or just clobbered.. + */ + .section .sched.text +ENTRY(__down_failed) + CFI_STARTPROC + FRAME + pushl %edx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET edx,0 + pushl %ecx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET ecx,0 + call __down + popl %ecx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE ecx + popl %edx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE edx + ENDFRAME + ret + CFI_ENDPROC + END(__down_failed) + +ENTRY(__down_failed_interruptible) + CFI_STARTPROC + FRAME + pushl %edx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET edx,0 + pushl %ecx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET ecx,0 + call __down_interruptible + popl %ecx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE ecx + popl %edx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE edx + ENDFRAME + ret + CFI_ENDPROC + END(__down_failed_interruptible) + +ENTRY(__down_failed_trylock) + CFI_STARTPROC + FRAME + pushl %edx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET edx,0 + pushl %ecx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET ecx,0 + call __down_trylock + popl %ecx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE ecx + popl %edx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE edx + ENDFRAME + ret + CFI_ENDPROC + END(__down_failed_trylock) + +ENTRY(__up_wakeup) + CFI_STARTPROC + FRAME + pushl %edx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET edx,0 + pushl %ecx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET ecx,0 + call __up + popl %ecx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE ecx + popl %edx + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE edx + ENDFRAME + ret + CFI_ENDPROC + END(__up_wakeup) + +/* + * rw spinlock fallbacks + */ +#ifdef CONFIG_SMP +ENTRY(__write_lock_failed) + CFI_STARTPROC simple + FRAME +2: LOCK_PREFIX + addl $ RW_LOCK_BIAS,(%eax) +1: rep; nop + cmpl $ RW_LOCK_BIAS,(%eax) + jne 1b + LOCK_PREFIX + subl $ RW_LOCK_BIAS,(%eax) + jnz 2b + ENDFRAME + ret + CFI_ENDPROC + END(__write_lock_failed) + +ENTRY(__read_lock_failed) + CFI_STARTPROC + FRAME +2: LOCK_PREFIX + incl (%eax) +1: rep; nop + cmpl $1,(%eax) + js 1b + LOCK_PREFIX + decl (%eax) + js 2b + ENDFRAME + ret + CFI_ENDPROC + END(__read_lock_failed) + +#endif diff --git a/arch/um/sys-i386/Makefile b/arch/um/sys-i386/Makefile index 374d61a19439..6289779ca67c 100644 --- a/arch/um/sys-i386/Makefile +++ b/arch/um/sys-i386/Makefile @@ -4,7 +4,7 @@ obj-y = bugs.o checksum.o delay.o fault.o ksyms.o ldt.o ptrace.o \ obj-$(CONFIG_MODE_SKAS) += stub.o stub_segv.o -subarch-obj-y = lib/bitops.o kernel/semaphore.o +subarch-obj-y = lib/bitops.o lib/semaphore.o subarch-obj-$(CONFIG_HIGHMEM) += mm/highmem.o subarch-obj-$(CONFIG_MODULES) += kernel/module.o diff --git a/include/asm-i386/frame.i b/include/asm-i386/frame.i new file mode 100644 index 000000000000..4d68ddce18b6 --- /dev/null +++ b/include/asm-i386/frame.i @@ -0,0 +1,24 @@ +#include +#include + +/* The annotation hides the frame from the unwinder and makes it look + like a ordinary ebp save/restore. This avoids some special cases for + frame pointer later */ +#ifdef CONFIG_FRAME_POINTER + .macro FRAME + pushl %ebp + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET ebp,0 + movl %esp,%ebp + .endm + .macro ENDFRAME + popl %ebp + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE ebp + .endm +#else + .macro FRAME + .endm + .macro ENDFRAME + .endm +#endif diff --git a/include/asm-um/alternative-asm.i b/include/asm-um/alternative-asm.i new file mode 100644 index 000000000000..cae9faca132f --- /dev/null +++ b/include/asm-um/alternative-asm.i @@ -0,0 +1,6 @@ +#ifndef __UM_ALTERNATIVE_ASM_I +#define __UM_ALTERNATIVE_ASM_I + +#include "asm/arch/alternative-asm.i" + +#endif diff --git a/include/asm-um/frame.i b/include/asm-um/frame.i new file mode 100644 index 000000000000..09d5dca5d928 --- /dev/null +++ b/include/asm-um/frame.i @@ -0,0 +1,6 @@ +#ifndef __UM_FRAME_I +#define __UM_FRAME_I + +#include "asm/arch/frame.i" + +#endif