vsprintf: use new vsprintf symbolic function pointer format

Use the '%pF' format to get rid of an "#ifdef DEBUG" and make some printks
atomic.

This removes the last in-tree uses of print_fn_descriptor_symbol(). I
marked print_fn_descriptor_symbol() deprecated and scheduled it for
removal next year to give time for out-of-tree modules to be updated.

parisc's print_fn_descriptor_symbol() is currently broken there (it needs
to dereference the function pointer similar to ia64 and power). This
patch shouldn't make anything worse, but it means we need to fix
dereference_function_descriptor() instead of print_fn_descriptor_symbol()
to get meaningful initcall_debug output.

Signed-off-by: Bjorn Helgaas <[e-mail]>
Cc: Jesse Barnes <[e-mail]>
Cc: Kyle McMartin <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Cc: Kay Sievers <[e-mail]>
Cc: Greg KH <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

Documentation/feature-removal-schedule.txt

···
 
 ---------------------------
 
+What: print_fn_descriptor_symbol()
+When: October 2009
+Why:  The %pF vsprintf format provides the same functionality in a
+      simpler way.  print_fn_descriptor_symbol() is deprecated but
+      still present to give out-of-tree modules time to change.
+Who:  Bjorn Helgaas <[e-mail]>
+
+---------------------------
+
 What:	/sys/o2cb symlink
 When:	January 2010
 Why:	/sys/fs/o2cb is the proper location for this information - /sys/o2cb

drivers/base/power/main.c

···
 
 void __suspend_report_result(const char *function, void *fn, int ret)
 {
-	if (ret) {
-		printk(KERN_ERR "%s(): ", function);
-		print_fn_descriptor_symbol("%s returns ", fn);
-		printk("%d\n", ret);
-	}
+	if (ret)
+		printk(KERN_ERR "%s(): %pF returns %d\n", function, fn, ret);
 }
 EXPORT_SYMBOL_GPL(__suspend_report_result);

include/linux/kallsyms.h

···
 }
 
 /*
- * Pretty-print a function pointer.
- *
- * ia64 and ppc64 function pointers are really function descriptors,
- * which contain a pointer the real address.
+ * Pretty-print a function pointer.  This function is deprecated.
+ * Please use the "%pF" vsprintf format instead.
  */
-static inline void print_fn_descriptor_symbol(const char *fmt, void *addr)
+static inline void __deprecated print_fn_descriptor_symbol(const char *fmt, void *addr)
 {
 #if defined(CONFIG_IA64) || defined(CONFIG_PPC64)
 	addr = *(void **)addr;