kprobes: kretprobes simplifications

 - consolidate duplicate code in all arch_prepare_kretprobe instances
   into common code
 - replace various odd helpers that use hlist_for_each_entry to get
   the first elemenet of a list with either a hlist_for_each_entry_save
   or an opencoded access to the first element in the caller
 - inline add_rp_inst into it's only remaining caller
 - use kretprobe_inst_table_head instead of opencoding it

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 850ee871e353..6fc623e41fd8 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -123,7 +123,8 @@ DECLARE_PER_CPU(struct kprobe *, current_kprobe);
 DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
 #ifdef ARCH_SUPPORTS_KRETPROBES
-extern void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs);
+extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
+                                   struct pt_regs *regs);
 #else /* ARCH_SUPPORTS_KRETPROBES */
 static inline void arch_prepare_kretprobe(struct kretprobe *rp,
                                         struct pt_regs *regs)
@@ -209,8 +210,6 @@ void jprobe_return(void);
 int register_kretprobe(struct kretprobe *rp);
 void unregister_kretprobe(struct kretprobe *rp);
 
-struct kretprobe_instance *get_free_rp_inst(struct kretprobe *rp);
-void add_rp_inst(struct kretprobe_instance *ri);
 void kprobe_flush_task(struct task_struct *tk);
 void recycle_rp_inst(struct kretprobe_instance *ri, struct hlist_head *head);
 #else /* CONFIG_KPROBES */