On 1/17/2025 1:54 PM, Xin Li wrote:
On 1/16/2025 9:18 PM, Ethan Zhao wrote:
Just swap the 2 arguments, and it should be:
+ switch_likely (etype, EVENT_TYPE_OTHER) {
after swapped the parameters as following:
+#define switch_likely(v,l) \
+ switch((__typeof__(v))__builtin_expect((v),(l)))
+
__visible noinstr void fred_entry_from_user(struct pt_regs *regs)
{
unsigned long error_code = regs->orig_ax;
+ unsigned short etype = regs->fred_ss.type & 0xf;
/* Invalidate orig_ax so that syscall_get_nr() works
correctly */
regs->orig_ax = -1;
- switch (regs->fred_ss.type) {
+ switch_likely (etype, (EVENT_TYPE_EXTINT == etype ||
EVENT_TYPE_OTHER == etype)) {
This is not what I suggested, the (l) argument should be only one
constant; __builtin_expect() doesn't allow 2 different constants.
That is why it couldn't be used in switch(var), while it works with if(true) else if (false).
Switch(var) needs a var returned by the __builtin_expect(), but it only could return Const.
Thanks,
Ethan
