sched: Consolidate open coded implementations of nice level frobbing into nice_to_rlimit() and rlimit_to_nice()

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/a568a1e3cc8e78648f41b5035fa5e381d36274da.1399532322.git.yangds.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Dongsheng Yang 2014-05-08 18:33:49 +09:00 committed by Ingo Molnar
parent a803f0261b
commit 7aa2c016db
4 changed files with 21 additions and 5 deletions

View file

@ -436,7 +436,7 @@ static void binder_set_nice(long nice)
set_user_nice(current, nice);
return;
}
min_nice = 20 - current->signal->rlim[RLIMIT_NICE].rlim_cur;
min_nice = rlimit_to_nice(current->signal->rlim[RLIMIT_NICE].rlim_cur);
binder_debug(BINDER_DEBUG_PRIORITY_CAP,
"%d: nice value %ld not allowed use %ld instead\n",
current->pid, nice, min_nice);

View file

@ -41,4 +41,20 @@
#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio)
#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO))
/*
* Convert nice value [19,-20] to rlimit style value [1,40].
*/
static inline long nice_to_rlimit(long nice)
{
return (MAX_NICE - nice + 1);
}
/*
* Convert rlimit style value [1,40] to nice value [-20, 19].
*/
static inline long rlimit_to_nice(long prio)
{
return (MAX_NICE - prio + 1);
}
#endif /* _SCHED_PRIO_H */

View file

@ -3033,7 +3033,7 @@ EXPORT_SYMBOL(set_user_nice);
int can_nice(const struct task_struct *p, const int nice)
{
/* convert nice value [19,-20] to rlimit style value [1,40] */
int nice_rlim = 20 - nice;
int nice_rlim = nice_to_rlimit(nice);
return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) ||
capable(CAP_SYS_NICE));

View file

@ -250,7 +250,7 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who)
else
p = current;
if (p) {
niceval = 20 - task_nice(p);
niceval = nice_to_rlimit(task_nice(p));
if (niceval > retval)
retval = niceval;
}
@ -261,7 +261,7 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who)
else
pgrp = task_pgrp(current);
do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
niceval = 20 - task_nice(p);
niceval = nice_to_rlimit(task_nice(p));
if (niceval > retval)
retval = niceval;
} while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
@ -277,7 +277,7 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who)
do_each_thread(g, p) {
if (uid_eq(task_uid(p), uid)) {
niceval = 20 - task_nice(p);
niceval = nice_to_rlimit(task_nice(p));
if (niceval > retval)
retval = niceval;
}