From d4ec36bac3de39b7e10ec8f42fbdd20d9a9ed753 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Sun, 21 Jun 2009 12:32:39 +0200 Subject: sched: Documentation/sched-rt-group: Fix style issues & bump version - add missing closing bracket - fix two 80-chars issues (as the rest of the document adheres to it) - bump a reference to kernel version, so the document does not feel aged Signed-off-by: Wolfram Sang Cc: Peter Zijlstra LKML-Reference: <1245580359-4465-1-git-send-email-w.sang@pengutronix.de> Signed-off-by: Ingo Molnar --- Documentation/scheduler/sched-rt-group.txt | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt index 1df7f9cdab05..86eabe6c3419 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//cpu.rt_runtime_us" -to control the CPU time reserved for each control group instead. +This uses the /cgroup virtual file system and +"/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. -- cgit v1.2.1