[PATCH v8 0/4] improvements to the nmi_backtrace code

On 16/08/16 20:50, Chris Metcalf wrote:

This is a rebase of the series onto v4.8-rc2, plus some changes from
various reviewers.

From the version 1 cover letter:

  This patch series modifies the trigger_xxx_backtrace() NMI-based
  remote backtracing code to make it more flexible, and makes a few
  small improvements along the way.

  The motivation comes from the task isolation code, where there are
  scenarios where we want to be able to diagnose a case where some cpu
  is about to interrupt a task-isolated cpu.  It can be helpful to
  see both where the interrupting cpu is, and also an approximation
  of where the cpu that is being interrupted is.  The nmi_backtrace
  framework allows us to discover the stack of the interrupted cpu.

I've tested that the change works as desired on tile, and build-tested
x86, arm, mips, and sparc64.  For x86 I confirmed that the generic
cpuidle stuff as well as the architecture-specific routines are in the
new cpuidle section.  For arm, mips, and sparc I just build-tested it
and made sure the generic cpuidle routines were in the new cpuidle
section, but I didn't attempt to figure out which the
platform-specific idle routines might be.  That might be more usefully
done by someone with platform experience in follow-up patches.

You can add runtime testing on arm to the list (I didn't try to exploit 
the new one-line-for-idle feature but there were no regressions). All 
patches:

Tested-by: Daniel Thompson <redacted>


Daniel.