kprobes: Rename [arch_]function_offset_within_entry() to [arch_]kprobe_on_func_entry()

Rename function_offset_within_entry() to scope it to kprobe namespace by
using kprobe_ prefix, and to also simplify it.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3aa6c7e2e4fb6e00f3c24fa306496a66edb558ea.1499443367.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/powerpc/kernel/kprobes.c

@@ -221,7 +221,7 @@ static nokprobe_inline void set_current_kprobe(struct kprobe *p, struct pt_regs
 	kcb->kprobe_saved_msr = regs->msr;
 }
 
-bool arch_function_offset_within_entry(unsigned long offset)
+bool arch_kprobe_on_func_entry(unsigned long offset)
 {
 #ifdef PPC64_ELF_ABI_v2
 #ifdef CONFIG_KPROBES_ON_FTRACE

include/linux/kprobes.h

@@ -267,8 +267,8 @@ extern int arch_init_kprobes(void);
 extern void show_registers(struct pt_regs *regs);
 extern void kprobes_inc_nmissed_count(struct kprobe *p);
 extern bool arch_within_kprobe_blacklist(unsigned long addr);
-extern bool arch_function_offset_within_entry(unsigned long offset);
-extern bool function_offset_within_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset);
+extern bool arch_kprobe_on_func_entry(unsigned long offset);
+extern bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset);
 
 extern bool within_kprobe_blacklist(unsigned long addr);
 

kernel/kprobes.c

@@ -1888,12 +1888,12 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
 }
 NOKPROBE_SYMBOL(pre_handler_kretprobe);
 
-bool __weak arch_function_offset_within_entry(unsigned long offset)
+bool __weak arch_kprobe_on_func_entry(unsigned long offset)
 {
 	return !offset;
 }
 
-bool function_offset_within_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset)
+bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset)
 {
 	kprobe_opcode_t *kp_addr = _kprobe_addr(addr, sym, offset);
 
@@ -1901,7 +1901,7 @@ bool function_offset_within_entry(kprobe_opcode_t *addr, const char *sym, unsign
 		return false;
 
 	if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset) ||
-						!arch_function_offset_within_entry(offset))
+						!arch_kprobe_on_func_entry(offset))
 		return false;
 
 	return true;
@@ -1914,7 +1914,7 @@ int register_kretprobe(struct kretprobe *rp)
 	int i;
 	void *addr;
 
-	if (!function_offset_within_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset))
+	if (!kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset))
 		return -EINVAL;
 
 	if (kretprobe_blacklist_size) {

kernel/trace/trace_kprobe.c

@@ -720,7 +720,7 @@ static int create_trace_kprobe(int argc, char **argv)
 			return ret;
 		}
 		if (offset && is_return &&
-		    !function_offset_within_entry(NULL, symbol, offset)) {
+		    !kprobe_on_func_entry(NULL, symbol, offset)) {
 			pr_info("Given offset is not valid for return probe.\n");
 			return -EINVAL;
 		}