cpuset: code-cleanup for started_after

cgroup(cgroup_scan_tasks) will initialize heap->gt for us.  This patch
removes started_after() and its helper-function.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 531b235..ebbc9b0 100644 (file)
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -709,36 +709,6 @@ done:
        /* Don't kfree(dattr) -- partition_sched_domains() does that. */
 }
 
-static inline int started_after_time(struct task_struct *t1,
-                                    struct timespec *time,
-                                    struct task_struct *t2)
-{
-       int start_diff = timespec_compare(&t1->start_time, time);
-       if (start_diff > 0) {
-               return 1;
-       } else if (start_diff < 0) {
-               return 0;
-       } else {
-               /*
-                * Arbitrarily, if two processes started at the same
-                * time, we'll say that the lower pointer value
-                * started first. Note that t2 may have exited by now
-                * so this may not be a valid pointer any longer, but
-                * that's fine - it still serves to distinguish
-                * between two tasks started (effectively)
-                * simultaneously.
-                */
-               return t1 > t2;
-       }
-}
-
-static inline int started_after(void *p1, void *p2)
-{
-       struct task_struct *t1 = p1;
-       struct task_struct *t2 = p2;
-       return started_after_time(t1, &t2->start_time, t2);
-}
-
 /**
  * cpuset_test_cpumask - test a task's cpus_allowed versus its cpuset's
  * @tsk: task to test
@@ -790,7 +760,12 @@ static int update_tasks_cpumask(struct cpuset *cs)
        struct ptr_heap heap;
        int retval;
 
-       retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, &started_after);
+       /*
+        * cgroup_scan_tasks() will initialize heap->gt for us.
+        * heap_init() is still needed here for we should not change
+        * cs->cpus_allowed when heap_init() fails.
+        */
+       retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL);
        if (retval)
                return retval;