MN10300: Save frame pointer in thread_info struct rather than global var
Save the current exception frame pointer in the thread_info struct rather than
in a global variable as the latter makes SMP tricky, especially when preemption
is also enabled.
This also replaces __frame with current_frame() and rearranges header file
inclusions to make it all compile.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
diff --git a/arch/mn10300/include/asm/frame.inc b/arch/mn10300/include/asm/frame.inc
index 406060e..2ee58e3 100644
--- a/arch/mn10300/include/asm/frame.inc
+++ b/arch/mn10300/include/asm/frame.inc
@@ -18,9 +18,7 @@
#ifndef __ASM_OFFSETS_H__
#include <asm/asm-offsets.h>
#endif
-#ifdef CONFIG_SMP
-#include <proc/smp-regs.h>
-#endif
+#include <asm/thread_info.h>
#define pi break
@@ -40,27 +38,15 @@
movm [d2,d3,a2,a3,exreg0,exreg1,exother],(sp)
mov sp,fp # FRAME pointer in A3
add -12,sp # allow for calls to be made
-#ifdef CONFIG_SMP
-#ifdef CONFIG_PREEMPT /* FIXME */
- mov epsw,d2
- and ~EPSW_IE,epsw
-#endif
- mov (CPUID),a0
- add a0,a0
- add a0,a0
- mov (___frame,a0),a1
- mov a1,(REG_NEXT,fp)
- mov fp,(___frame,a0)
-#ifdef CONFIG_PREEMPT /* FIXME */
- mov d2,epsw
-#endif
-#else /* CONFIG_SMP */
- mov (__frame),a1
- mov a1,(REG_NEXT,fp)
- mov fp,(__frame)
-#endif /* CONFIG_SMP */
- and ~EPSW_FE,epsw # disable the FPU inside the kernel
+ # push the exception frame onto the front of the list
+ GET_THREAD_INFO a1
+ mov (TI_frame,a1),a0
+ mov a0,(REG_NEXT,fp)
+ mov fp,(TI_frame,a1)
+
+ # disable the FPU inside the kernel
+ and ~EPSW_FE,epsw
# we may be holding current in E2
#ifdef CONFIG_MN10300_CURRENT_IN_E2
@@ -76,27 +62,11 @@
.macro RESTORE_ALL
# peel back the stack to the calling frame
# - this permits execve() to discard extra frames due to kernel syscalls
-#ifdef CONFIG_SMP
-#ifdef CONFIG_PREEMPT /* FIXME */
- mov epsw,d2
- and ~EPSW_IE,epsw
-#endif
- mov (CPUID),a0
- add a0,a0
- add a0,a0
- mov (___frame,a0),fp
+ GET_THREAD_INFO a0
+ mov (TI_frame,a0),fp
mov fp,sp
- mov (REG_NEXT,fp),d0 # userspace has regs->next == 0
- mov d0,(___frame,a0)
-#ifdef CONFIG_PREEMPT /* FIXME */
- mov d2,epsw
-#endif
-#else /* CONFIG_SMP */
- mov (__frame),fp
- mov fp,sp
- mov (REG_NEXT,fp),d0 # userspace has regs->next == 0
- mov d0,(__frame)
-#endif /* CONFIG_SMP */
+ mov (REG_NEXT,fp),d0
+ mov d0,(TI_frame,a0) # userspace has regs->next == 0
#ifndef CONFIG_MN10300_USING_JTAG
mov (REG_EPSW,fp),d0
diff --git a/arch/mn10300/include/asm/irq_regs.h b/arch/mn10300/include/asm/irq_regs.h
index a848cd2..97d0cb5 100644
--- a/arch/mn10300/include/asm/irq_regs.h
+++ b/arch/mn10300/include/asm/irq_regs.h
@@ -18,7 +18,11 @@
#define ARCH_HAS_OWN_IRQ_REGS
#ifndef __ASSEMBLY__
-#define get_irq_regs() (__frame)
+static inline __attribute__((const))
+struct pt_regs *get_irq_regs(void)
+{
+ return current_frame();
+}
#endif
#endif /* _ASM_IRQ_REGS_H */
diff --git a/arch/mn10300/include/asm/pgalloc.h b/arch/mn10300/include/asm/pgalloc.h
index a19f113..146bacf 100644
--- a/arch/mn10300/include/asm/pgalloc.h
+++ b/arch/mn10300/include/asm/pgalloc.h
@@ -11,7 +11,6 @@
#ifndef _ASM_PGALLOC_H
#define _ASM_PGALLOC_H
-#include <asm/processor.h>
#include <asm/page.h>
#include <linux/threads.h>
#include <linux/mm.h> /* for struct page */
diff --git a/arch/mn10300/include/asm/processor.h b/arch/mn10300/include/asm/processor.h
index 75c422a..4c1b5cc 100644
--- a/arch/mn10300/include/asm/processor.h
+++ b/arch/mn10300/include/asm/processor.h
@@ -13,10 +13,13 @@
#ifndef _ASM_PROCESSOR_H
#define _ASM_PROCESSOR_H
+#include <linux/threads.h>
+#include <linux/thread_info.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/cpu-regs.h>
-#include <linux/threads.h>
+#include <asm/uaccess.h>
+#include <asm/current.h>
/* Forward declaration, a strange C thing */
struct task_struct;
@@ -83,10 +86,6 @@
*/
#define TASK_UNMAPPED_BASE 0x30000000
-typedef struct {
- unsigned long seg;
-} mm_segment_t;
-
struct fpu_state_struct {
unsigned long fs[32]; /* fpu registers */
unsigned long fpcr; /* fpu control register */
@@ -99,7 +98,6 @@
unsigned long a3; /* kernel FP */
unsigned long wchan;
unsigned long usp;
- struct pt_regs *frame;
unsigned long fpu_flags;
#define THREAD_USING_FPU 0x00000001 /* T if this task is using the FPU */
#define THREAD_HAS_FPU 0x00000002 /* T if this task owns the FPU right now */
@@ -113,7 +111,6 @@
.sp = 0, \
.a3 = 0, \
.wchan = 0, \
- .frame = NULL, \
}
#define INIT_MMAP \
@@ -125,27 +122,20 @@
* - need to discard the frame stacked by the kernel thread invoking the execve
* syscall (see RESTORE_ALL macro)
*/
-#if defined(CONFIG_SMP) && defined(CONFIG_PREEMPT) /* FIXME */
-#define start_thread(regs, new_pc, new_sp) do { \
- int cpu; \
- preempt_disable(); \
- cpu = CPUID; \
- set_fs(USER_DS); \
- ___frame[cpu] = current->thread.uregs; \
- ___frame[cpu]->epsw = EPSW_nSL | EPSW_IE | EPSW_IM;\
- ___frame[cpu]->pc = new_pc; \
- ___frame[cpu]->sp = new_sp; \
- preempt_enable(); \
-} while (0)
-#else /* CONFIG_SMP && CONFIG_PREEMPT */
-#define start_thread(regs, new_pc, new_sp) do { \
- set_fs(USER_DS); \
- __frame = current->thread.uregs; \
- __frame->epsw = EPSW_nSL | EPSW_IE | EPSW_IM; \
- __frame->pc = new_pc; \
- __frame->sp = new_sp; \
-} while (0)
-#endif /* CONFIG_SMP && CONFIG_PREEMPT */
+static inline void start_thread(struct pt_regs *regs,
+ unsigned long new_pc, unsigned long new_sp)
+{
+ struct thread_info *ti = current_thread_info();
+ struct pt_regs *frame0;
+ set_fs(USER_DS);
+
+ frame0 = thread_info_to_uregs(ti);
+ frame0->epsw = EPSW_nSL | EPSW_IE | EPSW_IM;
+ frame0->pc = new_pc;
+ frame0->sp = new_sp;
+ ti->frame = frame0;
+}
+
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
diff --git a/arch/mn10300/include/asm/ptrace.h b/arch/mn10300/include/asm/ptrace.h
index c2b77bd..b696181 100644
--- a/arch/mn10300/include/asm/ptrace.h
+++ b/arch/mn10300/include/asm/ptrace.h
@@ -86,12 +86,6 @@
#ifdef __KERNEL__
-#ifdef CONFIG_SMP
-extern struct pt_regs *___frame[]; /* current frame pointer */
-#else
-extern struct pt_regs *__frame; /* current frame pointer */
-#endif
-
#define user_mode(regs) (((regs)->epsw & EPSW_nSL) == EPSW_nSL)
#define instruction_pointer(regs) ((regs)->pc)
#define user_stack_pointer(regs) ((regs)->sp)
diff --git a/arch/mn10300/include/asm/smp.h b/arch/mn10300/include/asm/smp.h
index b8585b4..a3930e4 100644
--- a/arch/mn10300/include/asm/smp.h
+++ b/arch/mn10300/include/asm/smp.h
@@ -93,19 +93,6 @@
extern void __cpu_die(unsigned int cpu);
#endif /* CONFIG_HOTPLUG_CPU */
-#ifdef CONFIG_PREEMPT /* FIXME */
-#define __frame \
- ({ \
- struct pt_regs *f; \
- preempt_disable(); \
- f = ___frame[CPUID]; \
- preempt_enable(); \
- f; \
- })
-#else
-#define __frame ___frame[CPUID]
-#endif
-
#endif /* __ASSEMBLY__ */
#else /* CONFIG_SMP */
#ifndef __ASSEMBLY__
diff --git a/arch/mn10300/include/asm/thread_info.h b/arch/mn10300/include/asm/thread_info.h
index 2001cb6..aa07a4a 100644
--- a/arch/mn10300/include/asm/thread_info.h
+++ b/arch/mn10300/include/asm/thread_info.h
@@ -16,10 +16,6 @@
#include <asm/page.h>
-#ifndef __ASSEMBLY__
-#include <asm/processor.h>
-#endif
-
#define PREEMPT_ACTIVE 0x10000000
#ifdef CONFIG_4KSTACKS
@@ -38,10 +34,14 @@
* must also be changed
*/
#ifndef __ASSEMBLY__
+typedef struct {
+ unsigned long seg;
+} mm_segment_t;
struct thread_info {
struct task_struct *task; /* main task structure */
struct exec_domain *exec_domain; /* execution domain */
+ struct pt_regs *frame; /* current exception frame */
unsigned long flags; /* low level flags */
__u32 cpu; /* current CPU */
__s32 preempt_count; /* 0 => preemptable, <0 => BUG */
@@ -55,6 +55,10 @@
__u8 supervisor_stack[0];
};
+#define thread_info_to_uregs(ti) \
+ ((struct pt_regs *) \
+ ((unsigned long)ti + THREAD_SIZE - sizeof(struct pt_regs)))
+
#else /* !__ASSEMBLY__ */
#ifndef __ASM_OFFSETS_H__
@@ -102,6 +106,12 @@
return ti;
}
+static inline __attribute__((const))
+struct pt_regs *current_frame(void)
+{
+ return current_thread_info()->frame;
+}
+
/* how to get the current stack pointer from C */
static inline unsigned long current_stack_pointer(void)
{
diff --git a/arch/mn10300/include/asm/uaccess.h b/arch/mn10300/include/asm/uaccess.h
index 47e7951..679dee0 100644
--- a/arch/mn10300/include/asm/uaccess.h
+++ b/arch/mn10300/include/asm/uaccess.h
@@ -14,9 +14,8 @@
/*
* User space memory access functions
*/
-#include <linux/sched.h>
+#include <linux/thread_info.h>
#include <asm/page.h>
-#include <asm/pgtable.h>
#include <asm/errno.h>
#define VERIFY_READ 0
@@ -29,7 +28,6 @@
*
* For historical reasons, these macros are grossly misnamed.
*/
-
#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
#define KERNEL_XDS MAKE_MM_SEG(0xBFFFFFFF)
diff --git a/arch/mn10300/kernel/asm-offsets.c b/arch/mn10300/kernel/asm-offsets.c
index 54cc5b6..96f24fa 100644
--- a/arch/mn10300/kernel/asm-offsets.c
+++ b/arch/mn10300/kernel/asm-offsets.c
@@ -23,6 +23,7 @@
OFFSET(TI_task, thread_info, task);
OFFSET(TI_exec_domain, thread_info, exec_domain);
+ OFFSET(TI_frame, thread_info, frame);
OFFSET(TI_flags, thread_info, flags);
OFFSET(TI_cpu, thread_info, cpu);
OFFSET(TI_preempt_count, thread_info, preempt_count);
@@ -66,7 +67,6 @@
OFFSET(THREAD_SP, thread_struct, sp);
OFFSET(THREAD_A3, thread_struct, a3);
OFFSET(THREAD_USP, thread_struct, usp);
- OFFSET(THREAD_FRAME, thread_struct, frame);
#ifdef CONFIG_FPU
OFFSET(THREAD_FPU_FLAGS, thread_struct, fpu_flags);
OFFSET(THREAD_FPU_STATE, thread_struct, fpu_state);
diff --git a/arch/mn10300/kernel/mn10300-watchdog.c b/arch/mn10300/kernel/mn10300-watchdog.c
index 965dd61..c5e12bf 100644
--- a/arch/mn10300/kernel/mn10300-watchdog.c
+++ b/arch/mn10300/kernel/mn10300-watchdog.c
@@ -122,7 +122,7 @@
static void watchdog_dump_register(void *dummy)
{
printk(KERN_ERR "--- Register Dump (CPU%d) ---\n", CPUID);
- show_registers(__frame);
+ show_registers(current_frame());
}
#endif
diff --git a/arch/mn10300/kernel/process.c b/arch/mn10300/kernel/process.c
index b2e85ed..0d0f804 100644
--- a/arch/mn10300/kernel/process.c
+++ b/arch/mn10300/kernel/process.c
@@ -228,6 +228,7 @@
unsigned long c_usp, unsigned long ustk_size,
struct task_struct *p, struct pt_regs *kregs)
{
+ struct thread_info *ti = task_thread_info(p);
struct pt_regs *c_uregs, *c_kregs, *uregs;
unsigned long c_ksp;
@@ -248,7 +249,7 @@
/* the new TLS pointer is passed in as arg #5 to sys_clone() */
if (clone_flags & CLONE_SETTLS)
- c_uregs->e2 = __frame->d3;
+ c_uregs->e2 = current_frame()->d3;
/* set up the return kernel frame if called from kernel_thread() */
c_kregs = c_uregs;
@@ -266,7 +267,7 @@
}
/* set up things up so the scheduler can start the new task */
- p->thread.frame = c_kregs;
+ ti->frame = c_kregs;
p->thread.a3 = (unsigned long) c_kregs;
p->thread.sp = c_ksp;
p->thread.pc = (unsigned long) ret_from_fork;
@@ -278,25 +279,26 @@
/*
* clone a process
- * - tlsptr is retrieved by copy_thread() from __frame->d3
+ * - tlsptr is retrieved by copy_thread() from current_frame()->d3
*/
asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp,
int __user *parent_tidptr, int __user *child_tidptr,
int __user *tlsptr)
{
- return do_fork(clone_flags, newsp ?: __frame->sp, __frame, 0,
- parent_tidptr, child_tidptr);
+ return do_fork(clone_flags, newsp ?: current_frame()->sp,
+ current_frame(), 0, parent_tidptr, child_tidptr);
}
asmlinkage long sys_fork(void)
{
- return do_fork(SIGCHLD, __frame->sp, __frame, 0, NULL, NULL);
+ return do_fork(SIGCHLD, current_frame()->sp,
+ current_frame(), 0, NULL, NULL);
}
asmlinkage long sys_vfork(void)
{
- return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, __frame->sp, __frame,
- 0, NULL, NULL);
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, current_frame()->sp,
+ current_frame(), 0, NULL, NULL);
}
asmlinkage long sys_execve(const char __user *name,
@@ -310,7 +312,7 @@
error = PTR_ERR(filename);
if (IS_ERR(filename))
return error;
- error = do_execve(filename, argv, envp, __frame);
+ error = do_execve(filename, argv, envp, current_frame());
putname(filename);
return error;
}
diff --git a/arch/mn10300/kernel/signal.c b/arch/mn10300/kernel/signal.c
index d4de05a..690f4e9 100644
--- a/arch/mn10300/kernel/signal.c
+++ b/arch/mn10300/kernel/signal.c
@@ -91,7 +91,7 @@
*/
asmlinkage long sys_sigaltstack(const stack_t __user *uss, stack_t *uoss)
{
- return do_sigaltstack(uss, uoss, __frame->sp);
+ return do_sigaltstack(uss, uoss, current_frame()->sp);
}
/*
@@ -156,10 +156,11 @@
*/
asmlinkage long sys_sigreturn(void)
{
- struct sigframe __user *frame = (struct sigframe __user *) __frame->sp;
+ struct sigframe __user *frame;
sigset_t set;
long d0;
+ frame = (struct sigframe __user *) current_frame()->sp;
if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__get_user(set.sig[0], &frame->sc.oldmask))
@@ -176,7 +177,7 @@
recalc_sigpending();
spin_unlock_irq(¤t->sighand->siglock);
- if (restore_sigcontext(__frame, &frame->sc, &d0))
+ if (restore_sigcontext(current_frame(), &frame->sc, &d0))
goto badframe;
return d0;
@@ -191,11 +192,11 @@
*/
asmlinkage long sys_rt_sigreturn(void)
{
- struct rt_sigframe __user *frame =
- (struct rt_sigframe __user *) __frame->sp;
+ struct rt_sigframe __user *frame;
sigset_t set;
- unsigned long d0;
+ long d0;
+ frame = (struct rt_sigframe __user *) current_frame()->sp;
if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
@@ -207,10 +208,11 @@
recalc_sigpending();
spin_unlock_irq(¤t->sighand->siglock);
- if (restore_sigcontext(__frame, &frame->uc.uc_mcontext, &d0))
+ if (restore_sigcontext(current_frame(), &frame->uc.uc_mcontext, &d0))
goto badframe;
- if (do_sigaltstack(&frame->uc.uc_stack, NULL, __frame->sp) == -EFAULT)
+ if (do_sigaltstack(&frame->uc.uc_stack, NULL, current_frame()->sp) ==
+ -EFAULT)
goto badframe;
return d0;
@@ -572,7 +574,7 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
- tracehook_notify_resume(__frame);
+ tracehook_notify_resume(current_frame());
if (current->replacement_session_keyring)
key_replace_session_keyring();
}
diff --git a/arch/mn10300/kernel/switch_to.S b/arch/mn10300/kernel/switch_to.S
index b08cb2e..9074d0f 100644
--- a/arch/mn10300/kernel/switch_to.S
+++ b/arch/mn10300/kernel/switch_to.S
@@ -38,15 +38,6 @@
mov d1,a1
# save prev context
-#ifdef CONFIG_SMP
- mov (CPUID),a2
- add a2,a2
- add a2,a2
- mov (___frame,a2),d0
-#else /* CONFIG_SMP */
- mov (__frame),d0
-#endif /* CONFIG_SMP */
- mov d0,(THREAD_FRAME,a0)
mov __switch_back,d0
mov d0,(THREAD_PC,a0)
mov sp,a2
@@ -68,15 +59,6 @@
mov a2,e2
#endif
- mov (THREAD_FRAME,a1),a2
-#ifdef CONFIG_SMP
- mov (CPUID),a0
- add a0,a0
- add a0,a0
- mov a2,(___frame,a0)
-#else /* CONFIG_SMP */
- mov a2,(__frame)
-#endif /* CONFIG_SMP */
mov (THREAD_PC,a1),a2
mov d2,d0 # for ret_from_fork
mov d0,a0 # for __switch_to
diff --git a/arch/mn10300/kernel/traps.c b/arch/mn10300/kernel/traps.c
index c924a1d..b90c3f1 100644
--- a/arch/mn10300/kernel/traps.c
+++ b/arch/mn10300/kernel/traps.c
@@ -45,14 +45,6 @@
#error "INTERRUPT_VECTOR_BASE not aligned to 16MiB boundary!"
#endif
-#ifdef CONFIG_SMP
-struct pt_regs *___frame[NR_CPUS]; /* current frame pointer */
-EXPORT_SYMBOL(___frame);
-#else /* CONFIG_SMP */
-struct pt_regs *__frame; /* current frame pointer */
-EXPORT_SYMBOL(__frame);
-#endif /* CONFIG_SMP */
-
int kstack_depth_to_print = 24;
spinlock_t die_lock = __SPIN_LOCK_UNLOCKED(die_lock);
diff --git a/mm/maccess.c b/mm/maccess.c
index 4e348db..e2b6f56 100644
--- a/mm/maccess.c
+++ b/mm/maccess.c
@@ -1,9 +1,9 @@
/*
* Access kernel memory without faulting.
*/
-#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/mm.h>
+#include <linux/uaccess.h>
/**
* probe_kernel_read(): safely attempt to read from a location