[IA64] optimize pagefaults a little

Get rid of the notifier list and call the kprobes code directly
if compiled in.  This mirrors the changes that recently went
into powerpc, s390 and sparc64.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This commit is contained in:
Christoph Hellwig 2007-05-16 14:52:19 +02:00 committed by Tony Luck
parent 17028c5c91
commit 576fe0bd7e
4 changed files with 28 additions and 37 deletions

View file

@ -820,7 +820,7 @@ out:
return 1;
}
static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)
int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)
{
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
@ -904,13 +904,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
if (post_kprobes_handler(args->regs))
ret = NOTIFY_STOP;
break;
case DIE_PAGE_FAULT:
/* kprobe_running() needs smp_processor_id() */
preempt_disable();
if (kprobe_running() &&
kprobes_fault_handler(args->regs, args->trapnr))
ret = NOTIFY_STOP;
preempt_enable();
default:
break;
}

View file

@ -19,36 +19,24 @@
extern void die (char *, struct pt_regs *, long);
#ifdef CONFIG_KPROBES
ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
/* Hook to register for page fault notifications */
int register_page_fault_notifier(struct notifier_block *nb)
static inline int notify_page_fault(struct pt_regs *regs, int trap)
{
return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
}
int ret = 0;
int unregister_page_fault_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
}
if (!user_mode(regs)) {
/* kprobe_running() needs smp_processor_id() */
preempt_disable();
if (kprobe_running() && kprobes_fault_handler(regs, trap))
ret = 1;
preempt_enable();
}
static inline int notify_page_fault(enum die_val val, const char *str,
struct pt_regs *regs, long err, int trap, int sig)
{
struct die_args args = {
.regs = regs,
.str = str,
.err = err,
.trapnr = trap,
.signr = sig
};
return atomic_notifier_call_chain(&notify_page_fault_chain, val, &args);
return ret;
}
#else
static inline int notify_page_fault(enum die_val val, const char *str,
struct pt_regs *regs, long err, int trap, int sig)
static inline int notify_page_fault(struct pt_regs *regs, int trap)
{
return NOTIFY_DONE;
return 0;
}
#endif
@ -117,8 +105,7 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
/*
* This is to handle the kprobes on user space access instructions
*/
if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, code, TRAP_BRKPT,
SIGSEGV) == NOTIFY_STOP)
if (notify_page_fault(regs, TRAP_BRKPT))
return;
down_read(&mm->mmap_sem);

View file

@ -28,14 +28,24 @@
*/
#include <linux/notifier.h>
extern int register_page_fault_notifier(struct notifier_block *);
extern int unregister_page_fault_notifier(struct notifier_block *);
/*
* These are only here because kprobes.c wants them to implement a
* blatant layering violation. Will hopefully go away soon once all
* architectures are updated.
*/
static inline int register_page_fault_notifier(struct notifier_block *nb)
{
return 0;
}
static inline int unregister_page_fault_notifier(struct notifier_block *nb)
{
return 0;
}
enum die_val {
DIE_BREAK = 1,
DIE_FAULT,
DIE_OOPS,
DIE_PAGE_FAULT,
DIE_MACHINE_HALT,
DIE_MACHINE_RESTART,
DIE_MCA_MONARCH_ENTER,

View file

@ -120,6 +120,7 @@ struct arch_specific_insn {
unsigned short slot;
};
extern int kprobes_fault_handler(struct pt_regs *regs, int trapnr);
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);