Hi all,

We are trying to run OProfile on Nexus 7 having Krait CPU. (Actually, Oprofile doesn't recognize krait but since, Krait is similar to Cortex-A15 we used event mappings of Cortex-A15).

The problem we are facing is :

  As Krait has 4-cores and linux kernel being SMP system, all cores except for core 0, go offline and come online as and when load demands.

   We are not able to collect the samples from any core except for core 0.

We tried:
   We tried using register_cpu_notifier to register for CPU status changes, so that we can register for overflow interrupts when a CPU come online, but these registered overflow interrupts are never called.

Any help to solve this would be really grateful.

Attached is the modified oprofile_perf.c