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authorTejun Heo <tj@kernel.org>2009-08-14 14:41:02 +0900
committerTejun Heo <tj@kernel.org>2009-08-14 14:45:31 +0900
commit384be2b18a5f9475eab9ca2bdfa95cc1a04ef59c (patch)
tree04c93f391a1b65c8bf8d7ba8643c07d26c26590a /Documentation/scheduler/sched-rt-group.txt
parenta76761b621bcd8336065c4fe3a74f046858bc34c (diff)
parent142d44b0dd6741a64a7bdbe029110e7c1dcf1d23 (diff)
Merge branch 'percpu-for-linus' into percpu-for-next
Conflicts: arch/sparc/kernel/smp_64.c arch/x86/kernel/cpu/perf_counter.c arch/x86/kernel/setup_percpu.c drivers/cpufreq/cpufreq_ondemand.c mm/percpu.c Conflicts in core and arch percpu codes are mostly from commit ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all the first chunk allocators into mm/percpu.c, the changes are moved from arch code to mm/percpu.c. Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'Documentation/scheduler/sched-rt-group.txt')
-rw-r--r--Documentation/scheduler/sched-rt-group.txt13
1 files changed, 7 insertions, 6 deletions
diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt
index 1df7f9cdab0..86eabe6c341 100644
--- a/Documentation/scheduler/sched-rt-group.txt
+++ b/Documentation/scheduler/sched-rt-group.txt
@@ -73,7 +73,7 @@ The remaining CPU time will be used for user input and other tasks. Because
realtime tasks have explicitly allocated the CPU time they need to perform
their tasks, buffer underruns in the graphics or audio can be eliminated.
-NOTE: the above example is not fully implemented as of yet (2.6.25). We still
+NOTE: the above example is not fully implemented yet. We still
lack an EDF scheduler to make non-uniform periods usable.
@@ -140,14 +140,15 @@ The other option is:
.o CONFIG_CGROUP_SCHED (aka "Basis for grouping tasks" = "Control groups")
-This uses the /cgroup virtual file system and "/cgroup/<cgroup>/cpu.rt_runtime_us"
-to control the CPU time reserved for each control group instead.
+This uses the /cgroup virtual file system and
+"/cgroup/<cgroup>/cpu.rt_runtime_us" to control the CPU time reserved for each
+control group instead.
For more information on working with control groups, you should read
Documentation/cgroups/cgroups.txt as well.
-Group settings are checked against the following limits in order to keep the configuration
-schedulable:
+Group settings are checked against the following limits in order to keep the
+configuration schedulable:
\Sum_{i} runtime_{i} / global_period <= global_runtime / global_period
@@ -189,7 +190,7 @@ Implementing SCHED_EDF might take a while to complete. Priority Inheritance is
the biggest challenge as the current linux PI infrastructure is geared towards
the limited static priority levels 0-99. With deadline scheduling you need to
do deadline inheritance (since priority is inversely proportional to the
-deadline delta (deadline - now).
+deadline delta (deadline - now)).
This means the whole PI machinery will have to be reworked - and that is one of
the most complex pieces of code we have.