There are all changes related to cpu hotplug path and would like to seek
upstream review. These are all patches in Qualcomm downstream kernel
for a quite long time. First patch sets the rt prioity to hotplug
task and second patch adds cpuhp trace events.
1) cpu-hotplug: Always use real time scheduling when hotplugging a CPU
2) cpu/hotplug: Add cpuhp_latency trace event
Example logs:-
cpu online -
cpuhp/4-200 [004] .... 223.891886: cpuhp_enter: cpu: 0004 target:
213 step: 212 (sched_cpu_activate)
cpuhp/4-200 [004] .... 223.891894: cpuhp_exit: cpu: 0004 state:
212 step: 212 ret: 0
sh-176 [000] .... 223.891912: cpuhp_exit: cpu: 0004 state:
213 step: 86 ret: 0
sh-176 [000] .... 223.891915: cpuhp_latency: cpu:4
state:online latency:3874 USEC ret: 0
cpu offline -
sh-176 [000] .... 265.193490: cpuhp_exit: cpu: 0004 state:
2 step: 2 ret: 0
sh-176 [000] .... 265.193494: cpuhp_latency: cpu:4
state:offline latency:57431 USEC ret: 0
Prasad Sodagudi (1):
cpu/hotplug: Add cpuhp_latency trace event
Syed Rameez Mustafa (1):
cpu-hotplug: Always use real time scheduling when hotplugging a CPU
include/trace/events/cpuhp.h | 29 +++++++++++++++++++++++++
kernel/cpu.c | 50 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 79 insertions(+)
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