I have an STM32F410 cortex M4 clocked @100MHz. I notify an high priority task from another, with lower priority, using xTaskNotifyGive()/ulTaskNotifyTake().
The firmware is compiled with arm-gcc:
~$ arm-none-eabi-gcc --version arm-none-eabi-gcc (GNU Tools for ARM Embedded Processors) 5.4.1 20160609 (release) [ARM/embedded-5-branch revision 237715]
and I already use -O3 optimization.
Moving a pin I can measure time between notification and task wakeup. It is about 4us.
Is it possible to speed up notification (I think also context switch)?