compiler.h: Fix annotation macro misplacement with Clang

When building with Clang and CONFIG_TRACE_BRANCH_PROFILING, there are a
lot of unreachable warnings, like:

  arch/x86/kernel/traps.o: warning: objtool: handle_xfd_event()+0x134: unreachable instruction

Without an input to the inline asm, 'volatile' is ignored for some
reason and Clang feels free to move the reachable() annotation away from
its intended location.

Fix that by re-adding the counter value to the inputs.

Fixes: f1069a8 ("compiler.h: Avoid using inline asm operand modifiers")
Fixes: c199f64 ("instrumentation.h: Avoid using inline asm operand modifiers")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Link: https://lore.kernel.org/r/0417e96909b97a406323409210de7bf13df0b170.1636410380.git.jpoimboe@redhat.com
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Cc: Vasily Gorbik <[email protected]>
Cc: Miroslav Benes <[email protected]>

Author: jpoimboe

include/linux/compiler.h

@@ -121,15 +121,15 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
 	asm volatile(__stringify_label(c) ":\n\t"			\
 		     ".pushsection .discard.reachable\n\t"		\
 		     ".long " __stringify_label(c) "b - .\n\t"		\
-		     ".popsection\n\t");				\
+		     ".popsection\n\t" : : "i" (c));			\
 })
 #define annotate_reachable() __annotate_reachable(__COUNTER__)
 
 #define __annotate_unreachable(c) ({					\
 	asm volatile(__stringify_label(c) ":\n\t"			\
 		     ".pushsection .discard.unreachable\n\t"		\
 		     ".long " __stringify_label(c) "b - .\n\t"		\
-		     ".popsection\n\t");				\
+		     ".popsection\n\t" : : "i" (c));			\
 })
 #define annotate_unreachable() __annotate_unreachable(__COUNTER__)
 

include/linux/instrumentation.h

@@ -11,7 +11,7 @@
 	asm volatile(__stringify(c) ": nop\n\t"				\
 		     ".pushsection .discard.instr_begin\n\t"		\
 		     ".long " __stringify(c) "b - .\n\t"		\
-		     ".popsection\n\t");				\
+		     ".popsection\n\t" : : "i" (c));			\
 })
 #define instrumentation_begin() __instrumentation_begin(__COUNTER__)
 
@@ -50,7 +50,7 @@
 	asm volatile(__stringify(c) ": nop\n\t"				\
 		     ".pushsection .discard.instr_end\n\t"		\
 		     ".long " __stringify(c) "b - .\n\t"		\
-		     ".popsection\n\t");				\
+		     ".popsection\n\t" : : "i" (c));			\
 })
 #define instrumentation_end() __instrumentation_end(__COUNTER__)
 #else