Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 576fe0bd authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Tony Luck
Browse files

[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: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
parent 17028c5c

arch/ia64/kernel/kprobes.c

+1 −8
Original line number Diff line number Diff line
@@ -820,7 +820,7 @@ static int __kprobes post_kprobes_handler(struct pt_regs *regs) 
	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;

	}

arch/ia64/mm/fault.c

+14 −27
Original line number Diff line number Diff line
@@ -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)

{

	return atomic_notifier_chain_register(&notify_page_fault_chain, nb);

}



int unregister_page_fault_notifier(struct notifier_block *nb)

static inline int notify_page_fault(struct pt_regs *regs, int trap)

{

	return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);

	int ret = 0;



	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);

include/asm-ia64/kdebug.h

+13 −3
Original line number Diff line number Diff line
@@ -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,

include/asm-ia64/kprobes.h

+1 −0
Original line number Diff line number Diff line
@@ -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);