[yocto] preempt-rt zedboard

[Edward Vidal]

Hello,
after many attempts I create a script to test if the patch would work.
#!/bin/bash
echo "removing older version"
rm -rf linux-stable-rt
echo "extracting a clean version"
tar xfz linux-stable-rt.tgz
echo "going to toplevel dir"
cd linux-stable-rt
echo "checkout of version before the patch"
git checkout v3.6.11.1
echo "checking which files will be patched"
git apply --stat ~/Downloads/patch-3.6.11.1-2
echo "checking if the patch can be applied without errors"
git apply --check ~/Downloads/patch-3.6.11.1-2
if I did not get errors then I executed
make ARCH=arm CROSS_COMPILE=arm-xilinx-linux-gnueabi- menuconfig
Kernel Features
Preemption Model (Voluntary Kernel Preemption (Desktop))  ---

─ Voluntary Kernel Preemption (Desktop) ─────────────────┐
  │ CONFIG_PREEMPT_VOLUNTARY:
│
  │
│
  │ This option reduces the latency of the kernel by adding more
│
  │ "explicit preemption points" to the kernel code. These new
│
  │ preemption points have been selected to reduce the maximum
│
  │ latency of rescheduling, providing faster application reactions,
│
  │ at the cost of slightly lower throughput.
│
  │
│
  │ This allows reaction to interactive events by allowing a
│
  │ low priority process to voluntarily preempt itself even if it
│
  │ is in kernel mode executing a system call. This allows
│
  │ applications to run more 'smoothly' even when the system is
│
  │ under load.
│
  │
│
  │ Select this if you are building a kernel for a desktop system.

git apply  < ~/Downloads/patch-3.6.11.1-2
<stdin>:5054: new blank line at EOF.
+
warning: 1 line adds whitespace errors.
After the patch was applied nothing seem to have changed.

I am thinking this should be the option selected instead of the one above.

Preemptible Kernel (Low-Latency Desktop) ────────────────┐
  │ CONFIG_PREEMPT:
│
  │
│
  │ This option reduces the latency of the kernel by making
│
  │ all kernel code (that is not executing in a critical section)
│
  │ preemptible.  This allows reaction to interactive events by
│
  │ permitting a low priority process to be preempted involuntarily
│
  │ even if it is in kernel mode executing a system call and would
│
  │ otherwise not be about to reach a natural preemption point.
│
  │ This allows applications to run more 'smoothly' even when the
│
  │ system is under load, at the cost of slightly lower throughput
│
  │ and a slight runtime overhead to kernel code.
│
  │
│
  │ Select this if you are building a kernel for a desktop or
│
  │ embedded system with latency requirements in the milliseconds
│
  │ range.
I still have not figured out how to merge the linux-digilent with the
patched linux-stable-rt kernel.

Any and all help will be appreciated.
Thanks
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