2 files changed, 24 insertions, 15 deletions

diff --git a/Documentation/scheduler/sched-design-CFS.txt b/Documentation/scheduler/sched-design-CFS.txt
index 8239ebbcddc..99961993257 100644
--- a/Documentation/scheduler/sched-design-CFS.txt
+++ b/Documentation/scheduler/sched-design-CFS.txt
@@ -164,7 +164,7 @@ This is the (partial) list of the hooks:
    It puts the scheduling entity (task) into the red-black tree and
    increments the nr_running variable.
 
- - dequeue_tree(...)
+ - dequeue_task(...)
 
    When a task is no longer runnable, this function is called to keep the
    corresponding scheduling entity out of the red-black tree.  It decrements
@@ -195,11 +195,6 @@ This is the (partial) list of the hooks:
    This function is mostly called from time tick functions; it might lead to
    process switch.  This drives the running preemption.
 
- - task_new(...)
-
-   The core scheduler gives the scheduling module an opportunity to manage new
-   task startup.  The CFS scheduling module uses it for group scheduling, while
-   the scheduling module for a real-time task does not use it.
 
 
 
diff --git a/Documentation/scheduler/sched-domains.txt b/Documentation/scheduler/sched-domains.txt
index 373ceacc367..b7ee379b651 100644
--- a/Documentation/scheduler/sched-domains.txt
+++ b/Documentation/scheduler/sched-domains.txt
@@ -1,8 +1,7 @@
-Each CPU has a "base" scheduling domain (struct sched_domain). These are
-accessed via cpu_sched_domain(i) and this_sched_domain() macros. The domain
+Each CPU has a "base" scheduling domain (struct sched_domain). The domain
 hierarchy is built from these base domains via the ->parent pointer. ->parent
-MUST be NULL terminated, and domain structures should be per-CPU as they
-are locklessly updated.
+MUST be NULL terminated, and domain structures should be per-CPU as they are
+locklessly updated.
 
 Each scheduling domain spans a number of CPUs (stored in the ->span field).
 A domain's span MUST be a superset of it child's span (this restriction could
@@ -26,11 +25,26 @@ is treated as one entity. The load of a group is defined as the sum of the
 load of each of its member CPUs, and only when the load of a group becomes
 out of balance are tasks moved between groups.
 
-In kernel/sched.c, rebalance_tick is run periodically on each CPU. This
-function takes its CPU's base sched domain and checks to see if has reached
-its rebalance interval. If so, then it will run load_balance on that domain.
-rebalance_tick then checks the parent sched_domain (if it exists), and the
-parent of the parent and so forth.
+In kernel/sched.c, trigger_load_balance() is run periodically on each CPU
+through scheduler_tick(). It raises a softirq after the next regularly scheduled
+rebalancing event for the current runqueue has arrived. The actual load
+balancing workhorse, run_rebalance_domains()->rebalance_domains(), is then run
+in softirq context (SCHED_SOFTIRQ).
+
+The latter function takes two arguments: the current CPU and whether it was idle
+at the time the scheduler_tick() happened and iterates over all sched domains
+our CPU is on, starting from its base domain and going up the ->parent chain.
+While doing that, it checks to see if the current domain has exhausted its
+rebalance interval. If so, it runs load_balance() on that domain. It then checks
+the parent sched_domain (if it exists), and the parent of the parent and so
+forth.
+
+Initially, load_balance() finds the busiest group in the current sched domain.
+If it succeeds, it looks for the busiest runqueue of all the CPUs' runqueues in
+that group. If it manages to find such a runqueue, it locks both our initial
+CPU's runqueue and the newly found busiest one and starts moving tasks from it
+to our runqueue. The exact number of tasks amounts to an imbalance previously
+computed while iterating over this sched domain's groups.
 
 *** Implementing sched domains ***
 The "base" domain will "span" the first level of the hierarchy. In the case