[PATCH 1/1] HMP: Do not send IPI if core already waked up

Dear All,

This patch is related to HMP force up migration, it will avoid sending of unnecessary interrupts to CPUs of faster domain hence increase performance.

[PATCH 1/1] HMP: Do not send IPI if core already waked up

HMP: Do not send IPI if core already waked up

It is possible that we are sending IPI to a cpu in faster domain which is already waked up by other CPU in smaller domain.

HMP select the idle CPU using hmp_domain_min_load. Based on that HMP send IPI to the idle cpu in faster domain. There could be some latency by the core to wake up and set wake_for_idle_pull = 0. Next smaller cpu again check for idle CPU in faster domain and send IPI to already waked up CPU.

For example: In Octacore system, 0-3 are slower CPUs and 4-7 are faster CPUs. CPU0 and CPU1 has heavy tasks and CPU4 is idle. CPU0 execute hmp_force_up_migration find CPU4 as idle, it send IPI to CPU4 and return. After that CPU1 got the chance to run hmp_force_up_migration, it again find CPU4 as idle, send IPI to CPU4, which is not required.

Signed-off-by: rahulkhandelwal <rahul.khandelwal@spreadtrum.commailto:rahul.khandelwal@spreadtrum.com>