On Fri, Jun 04, 2021 at 01:31:48PM +0200, Peter Zijlstra wrote:

On Fri, Jun 04, 2021 at 11:44:00AM +0100, Will Deacon wrote:

quoted

quoted

+{
+	asm_volatile_goto("cbnz %0, %l[l_yes]"
+			  : : "r" (cond) : "cc", "memory" : l_yes);
+	return 0;
+l_yes:
+	return 1;
+}

nit: you don't need the "cc" clobber here.

Yeah I know, "cc" is implied.

It isn't needed at all here.  cbnz does not write to the condition
register.  Neither does it change or access memory, but the "memory"
clobber is to force a false dependency.  Writing "cc" as well looks a
bit confusing, given that.


Segher