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-rw-r--r--arch/arm/kernel/entry-armv.S24
-rw-r--r--arch/arm/kernel/iwmmxt.S2
-rw-r--r--arch/arm/kernel/process.c24
-rw-r--r--arch/arm/nwfpe/fpmodule.c25
-rw-r--r--arch/arm/vfp/vfpmodule.c71
-rw-r--r--include/asm-arm/thread_notify.h48
6 files changed, 135 insertions, 59 deletions
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index ab8e600c18c..86c92523a34 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -20,6 +20,7 @@
#include <asm/glue.h>
#include <asm/vfpmacros.h>
#include <asm/arch/entry-macro.S>
+#include <asm/thread_notify.h>
#include "entry-header.S"
@@ -560,10 +561,8 @@ ENTRY(__switch_to)
add ip, r1, #TI_CPU_SAVE
ldr r3, [r2, #TI_TP_VALUE]
stmia ip!, {r4 - sl, fp, sp, lr} @ Store most regs on stack
-#ifndef CONFIG_MMU
- add r2, r2, #TI_CPU_DOMAIN
-#else
- ldr r6, [r2, #TI_CPU_DOMAIN]!
+#ifdef CONFIG_MMU
+ ldr r6, [r2, #TI_CPU_DOMAIN]
#endif
#if __LINUX_ARM_ARCH__ >= 6
#ifdef CONFIG_CPU_32v6K
@@ -585,21 +584,20 @@ ENTRY(__switch_to)
#ifdef CONFIG_MMU
mcr p15, 0, r6, c3, c0, 0 @ Set domain register
#endif
-#ifdef CONFIG_VFP
- @ Always disable VFP so we can lazily save/restore the old
- @ state. This occurs in the context of the previous thread.
- VFPFMRX r4, FPEXC
- bic r4, r4, #FPEXC_ENABLE
- VFPFMXR FPEXC, r4
-#endif
#if defined(CONFIG_IWMMXT)
bl iwmmxt_task_switch
#elif defined(CONFIG_CPU_XSCALE)
- add r4, r2, #40 @ cpu_context_save->extra
+ add r4, r2, #TI_CPU_DOMAIN + 40 @ cpu_context_save->extra
ldmib r4, {r4, r5}
mar acc0, r4, r5
#endif
- ldmib r2, {r4 - sl, fp, sp, pc} @ Load all regs saved previously
+ mov r5, r0
+ add r4, r2, #TI_CPU_SAVE
+ ldr r0, =thread_notify_head
+ mov r1, #THREAD_NOTIFY_SWITCH
+ bl atomic_notifier_call_chain
+ mov r0, r5
+ ldmia r4, {r4 - sl, fp, sp, pc} @ Load all regs saved previously
__INIT
diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S
index 24c7b0477a0..af9e0ae952d 100644
--- a/arch/arm/kernel/iwmmxt.S
+++ b/arch/arm/kernel/iwmmxt.S
@@ -285,7 +285,7 @@ ENTRY(iwmmxt_task_switch)
bne 1f @ yes: block them for next task
ldr r5, =concan_owner
- add r6, r2, #(TI_IWMMXT_STATE - TI_CPU_DOMAIN) @ get next task Concan save area
+ add r6, r2, #TI_IWMMXT_STATE @ get next task Concan save area
ldr r5, [r5] @ get current Concan owner
teq r5, r6 @ next task owns it?
movne pc, lr @ no: leave Concan disabled
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 17c38dbf2f3..e1c77ee885a 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -33,6 +33,7 @@
#include <asm/leds.h>
#include <asm/processor.h>
#include <asm/system.h>
+#include <asm/thread_notify.h>
#include <asm/uaccess.h>
#include <asm/mach/time.h>
@@ -338,13 +339,9 @@ void exit_thread(void)
{
}
-static void default_fp_init(union fp_state *fp)
-{
- memset(fp, 0, sizeof(union fp_state));
-}
+ATOMIC_NOTIFIER_HEAD(thread_notify_head);
-void (*fp_init)(union fp_state *) = default_fp_init;
-EXPORT_SYMBOL(fp_init);
+EXPORT_SYMBOL_GPL(thread_notify_head);
void flush_thread(void)
{
@@ -353,22 +350,21 @@ void flush_thread(void)
memset(thread->used_cp, 0, sizeof(thread->used_cp));
memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
+ memset(&thread->fpstate, 0, sizeof(union fp_state));
+
+ thread_notify(THREAD_NOTIFY_FLUSH, thread);
#if defined(CONFIG_IWMMXT)
iwmmxt_task_release(thread);
#endif
- fp_init(&thread->fpstate);
-#if defined(CONFIG_VFP)
- vfp_flush_thread(&thread->vfpstate);
-#endif
}
void release_thread(struct task_struct *dead_task)
{
-#if defined(CONFIG_VFP)
- vfp_release_thread(&task_thread_info(dead_task)->vfpstate);
-#endif
+ struct thread_info *thread = task_thread_info(dead_task);
+
+ thread_notify(THREAD_NOTIFY_RELEASE, thread);
#if defined(CONFIG_IWMMXT)
- iwmmxt_task_release(task_thread_info(dead_task));
+ iwmmxt_task_release(thread);
#endif
}
diff --git a/arch/arm/nwfpe/fpmodule.c b/arch/arm/nwfpe/fpmodule.c
index 2dfe1ac42ee..7d977d23f02 100644
--- a/arch/arm/nwfpe/fpmodule.c
+++ b/arch/arm/nwfpe/fpmodule.c
@@ -33,7 +33,8 @@
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/init.h>
-/* XXX */
+
+#include <asm/thread_notify.h>
#include "softfloat.h"
#include "fpopcode.h"
@@ -56,16 +57,28 @@ void fp_send_sig(unsigned long sig, struct task_struct *p, int priv);
extern char fpe_type[];
#endif
+static int nwfpe_notify(struct notifier_block *self, unsigned long cmd, void *v)
+{
+ struct thread_info *thread = v;
+
+ if (cmd == THREAD_NOTIFY_FLUSH)
+ nwfpe_init_fpa(&thread->fpstate);
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block nwfpe_notifier_block = {
+ .notifier_call = nwfpe_notify,
+};
+
/* kernel function prototypes required */
void fp_setup(void);
/* external declarations for saved kernel symbols */
extern void (*kern_fp_enter)(void);
-extern void (*fp_init)(union fp_state *);
/* Original value of fp_enter from kernel before patched by fpe_init. */
static void (*orig_fp_enter)(void);
-static void (*orig_fp_init)(union fp_state *);
/* forward declarations */
extern void nwfpe_enter(void);
@@ -88,20 +101,20 @@ static int __init fpe_init(void)
printk(KERN_WARNING "NetWinder Floating Point Emulator V0.97 ("
NWFPE_BITS " precision)\n");
+ thread_register_notifier(&nwfpe_notifier_block);
+
/* Save pointer to the old FP handler and then patch ourselves in */
orig_fp_enter = kern_fp_enter;
- orig_fp_init = fp_init;
kern_fp_enter = nwfpe_enter;
- fp_init = nwfpe_init_fpa;
return 0;
}
static void __exit fpe_exit(void)
{
+ thread_unregister_notifier(&nwfpe_notifier_block);
/* Restore the values we saved earlier. */
kern_fp_enter = orig_fp_enter;
- fp_init = orig_fp_init;
}
/*
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 03486be0419..2476f4c2e76 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -15,6 +15,8 @@
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/init.h>
+
+#include <asm/thread_notify.h>
#include <asm/vfp.h>
#include "vfpinstr.h"
@@ -36,38 +38,55 @@ union vfp_state *last_VFP_context;
*/
unsigned int VFP_arch;
-/*
- * Per-thread VFP initialisation.
- */
-void vfp_flush_thread(union vfp_state *vfp)
+static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v)
{
- memset(vfp, 0, sizeof(union vfp_state));
+ struct thread_info *thread = v;
+ union vfp_state *vfp = &thread->vfpstate;
- vfp->hard.fpexc = FPEXC_ENABLE;
- vfp->hard.fpscr = FPSCR_ROUND_NEAREST;
+ switch (cmd) {
+ case THREAD_NOTIFY_FLUSH:
+ /*
+ * Per-thread VFP initialisation.
+ */
+ memset(vfp, 0, sizeof(union vfp_state));
- /*
- * Disable VFP to ensure we initialise it first.
- */
- fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_ENABLE);
+ vfp->hard.fpexc = FPEXC_ENABLE;
+ vfp->hard.fpscr = FPSCR_ROUND_NEAREST;
- /*
- * Ensure we don't try to overwrite our newly initialised
- * state information on the first fault.
- */
- if (last_VFP_context == vfp)
- last_VFP_context = NULL;
-}
+ /*
+ * Disable VFP to ensure we initialise it first.
+ */
+ fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_ENABLE);
-/*
- * Per-thread VFP cleanup.
- */
-void vfp_release_thread(union vfp_state *vfp)
-{
- if (last_VFP_context == vfp)
- last_VFP_context = NULL;
+ /*
+ * FALLTHROUGH: Ensure we don't try to overwrite our newly
+ * initialised state information on the first fault.
+ */
+
+ case THREAD_NOTIFY_RELEASE:
+ /*
+ * Per-thread VFP cleanup.
+ */
+ if (last_VFP_context == vfp)
+ last_VFP_context = NULL;
+ break;
+
+ case THREAD_NOTIFY_SWITCH:
+ /*
+ * Always disable VFP so we can lazily save/restore the
+ * old state.
+ */
+ fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_ENABLE);
+ break;
+ }
+
+ return NOTIFY_DONE;
}
+static struct notifier_block vfp_notifier_block = {
+ .notifier_call = vfp_notifier,
+};
+
/*
* Raise a SIGFPE for the current process.
* sicode describes the signal being raised.
@@ -281,6 +300,8 @@ static int __init vfp_init(void)
(vfpsid & FPSID_VARIANT_MASK) >> FPSID_VARIANT_BIT,
(vfpsid & FPSID_REV_MASK) >> FPSID_REV_BIT);
vfp_vector = vfp_support_entry;
+
+ thread_register_notifier(&vfp_notifier_block);
}
return 0;
}
diff --git a/include/asm-arm/thread_notify.h b/include/asm-arm/thread_notify.h
new file mode 100644
index 00000000000..8866e521684
--- /dev/null
+++ b/include/asm-arm/thread_notify.h
@@ -0,0 +1,48 @@
+/*
+ * linux/include/asm-arm/thread_notify.h
+ *
+ * Copyright (C) 2006 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef ASMARM_THREAD_NOTIFY_H
+#define ASMARM_THREAD_NOTIFY_H
+
+#ifdef __KERNEL__
+
+#ifndef __ASSEMBLY__
+
+#include <linux/notifier.h>
+#include <asm/thread_info.h>
+
+static inline int thread_register_notifier(struct notifier_block *n)
+{
+ extern struct atomic_notifier_head thread_notify_head;
+ return atomic_notifier_chain_register(&thread_notify_head, n);
+}
+
+static inline void thread_unregister_notifier(struct notifier_block *n)
+{
+ extern struct atomic_notifier_head thread_notify_head;
+ atomic_notifier_chain_unregister(&thread_notify_head, n);
+}
+
+static inline void thread_notify(unsigned long rc, struct thread_info *thread)
+{
+ extern struct atomic_notifier_head thread_notify_head;
+ atomic_notifier_call_chain(&thread_notify_head, rc, thread);
+}
+
+#endif
+
+/*
+ * These are the reason codes for the thread notifier.
+ */
+#define THREAD_NOTIFY_FLUSH 0
+#define THREAD_NOTIFY_RELEASE 1
+#define THREAD_NOTIFY_SWITCH 2
+
+#endif
+#endif