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-rw-r--r--kernel/compat.c21
-rw-r--r--kernel/sched.c8
-rw-r--r--kernel/sched_fair.c8
-rw-r--r--kernel/workqueue.c27
4 files changed, 46 insertions, 18 deletions
diff --git a/kernel/compat.c b/kernel/compat.c
index e167efce8423..c9e2ec0b34a8 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -1126,3 +1126,24 @@ compat_sys_sysinfo(struct compat_sysinfo __user *info)
return 0;
}
+
+/*
+ * Allocate user-space memory for the duration of a single system call,
+ * in order to marshall parameters inside a compat thunk.
+ */
+void __user *compat_alloc_user_space(unsigned long len)
+{
+ void __user *ptr;
+
+ /* If len would occupy more than half of the entire compat space... */
+ if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
+ return NULL;
+
+ ptr = arch_compat_alloc_user_space(len);
+
+ if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
+ return NULL;
+
+ return ptr;
+}
+EXPORT_SYMBOL_GPL(compat_alloc_user_space);
diff --git a/kernel/sched.c b/kernel/sched.c
index ed09d4f2a69c..dc85ceb90832 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3513,9 +3513,9 @@ void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
rtime = nsecs_to_cputime(p->se.sum_exec_runtime);
if (total) {
- u64 temp;
+ u64 temp = rtime;
- temp = (u64)(rtime * utime);
+ temp *= utime;
do_div(temp, total);
utime = (cputime_t)temp;
} else
@@ -3546,9 +3546,9 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
rtime = nsecs_to_cputime(cputime.sum_exec_runtime);
if (total) {
- u64 temp;
+ u64 temp = rtime;
- temp = (u64)(rtime * cputime.utime);
+ temp *= cputime.utime;
do_div(temp, total);
utime = (cputime_t)temp;
} else
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 9b5b4f86b742..db3f674ca49d 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -54,13 +54,13 @@ enum sched_tunable_scaling sysctl_sched_tunable_scaling
* Minimal preemption granularity for CPU-bound tasks:
* (default: 2 msec * (1 + ilog(ncpus)), units: nanoseconds)
*/
-unsigned int sysctl_sched_min_granularity = 2000000ULL;
-unsigned int normalized_sysctl_sched_min_granularity = 2000000ULL;
+unsigned int sysctl_sched_min_granularity = 750000ULL;
+unsigned int normalized_sysctl_sched_min_granularity = 750000ULL;
/*
* is kept at sysctl_sched_latency / sysctl_sched_min_granularity
*/
-static unsigned int sched_nr_latency = 3;
+static unsigned int sched_nr_latency = 8;
/*
* After fork, child runs first. If set to 0 (default) then
@@ -3630,7 +3630,7 @@ static inline int nohz_kick_needed(struct rq *rq, int cpu)
if (time_before(now, nohz.next_balance))
return 0;
- if (!rq->nr_running)
+ if (rq->idle_at_tick)
return 0;
first_pick_cpu = atomic_read(&nohz.first_pick_cpu);
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 727f24e563ae..f77afd939229 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1,19 +1,26 @@
/*
- * linux/kernel/workqueue.c
+ * kernel/workqueue.c - generic async execution with shared worker pool
*
- * Generic mechanism for defining kernel helper threads for running
- * arbitrary tasks in process context.
+ * Copyright (C) 2002 Ingo Molnar
*
- * Started by Ingo Molnar, Copyright (C) 2002
+ * Derived from the taskqueue/keventd code by:
+ * David Woodhouse <dwmw2@infradead.org>
+ * Andrew Morton
+ * Kai Petzke <wpp@marie.physik.tu-berlin.de>
+ * Theodore Ts'o <tytso@mit.edu>
*
- * Derived from the taskqueue/keventd code by:
+ * Made to use alloc_percpu by Christoph Lameter.
*
- * David Woodhouse <dwmw2@infradead.org>
- * Andrew Morton
- * Kai Petzke <wpp@marie.physik.tu-berlin.de>
- * Theodore Ts'o <tytso@mit.edu>
+ * Copyright (C) 2010 SUSE Linux Products GmbH
+ * Copyright (C) 2010 Tejun Heo <tj@kernel.org>
*
- * Made to use alloc_percpu by Christoph Lameter.
+ * This is the generic async execution mechanism. Work items as are
+ * executed in process context. The worker pool is shared and
+ * automatically managed. There is one worker pool for each CPU and
+ * one extra for works which are better served by workers which are
+ * not bound to any specific CPU.
+ *
+ * Please read Documentation/workqueue.txt for details.
*/
#include <linux/module.h>