on 2019/07/25 11:10, Yang Xu wrote:
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2372,7 +2372,7 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2,
unsigned long, arg3,
error = current->timer_slack_ns;
break;
case PR_SET_TIMERSLACK:
- if (arg2<= 0)
+ if (arg2 == 0)
current->timer_slack_ns =
current->default_timer_slack_ns;
A number of years ago Linus expressed approval of such comparisons with
unsigned quantities. He felt that it improves readability a little -
the reader doesn't have to scroll back and check the type.
Hi Andrew
It sounds good. ButWe still have to look at the actual situation. In here,
this comparisons with unsigned
quantities doesn't improvereadability. In turn, the code give user a
wrongdescription as man page said "
If arg2 is less than or equal to zero, the "current" timer slack is reset to the thread's
default" timer slack value."
If we set -1 in user space, we pass it into kernel as ULONG_MAX, it will not
use default timer_slack value.
Also, I guess that if value has no actual sense we can use this comparisons. In
here, arg2 represents slack time.
time will never less than 0.
ps: whether we change or not change this comparisons, it doesn't affect logic.
So if you think this patch is meaningless,
I will accept it.
Hi Andrew
what do you think about it? update it or keep it.
Thanks
Yang Xu
