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Re: Task switching problem
Dear Sir!
AL> Do you have assertions enabled? That might also give a clue as to what
AL> is happening. CYGPKG_INFRA_DEBUG is what you need.
>>
>> Num Thread Time Arg1 Arg2
>> 149 06 0x1d90 SCHED_LOCK 0x00000001 0x020053d4 radiorx_data()
>> 150 06 0x1d96 MUTEX_UNLOCK 0x0211dfc0 0x00000000 radio_mutex
>> 151 06 0x1d9f SCHED_UNLOCK 0x00000001 0x020053d4 radiorx_data()
>> 152 06 0x1db4 SCHED_LOCK 0x00000001 0x020054c4 radioErx_proc()
>> 153 06 0x1dbc SCHED_LOCK 0x00000002 0x0201adbc _flagwait
>> 154 06 0x1dc3 SCHED_UNLOCK 0x00000002 0x0201adbc _flagwait
>> 155 06 0x1dcf THREAD_SLEEP 0x0211dfe0 0x00000000 radioErx_thread
>> 156 06 0x1dd6 SCHED_LOCK 0x00000002 0x0201ae3c _flagwait
>> 157 06 0x1de0 SCHED_UNLOCK 0x00000002 0x0201ae3c _flagwait
>> 158 06 0x1dea SCHED_RESCHEDULE 0x00000001 0x00000000
>> 159 06 0x1df2 SCHED_RESCHEDULE 0x00000000 0x00000000
>> 160 06 0x1e0f THREAD_SWITCH 0x0211dfe0 0x0208cfe4 radioErx_thread => idle_thread
AL> What is happening at 152? Is your code locking the schedular before
AL> calling the flag_wait function?
It's ok. Flagwait piece of code works that way.
In file packages/hal/arm/arch/current/src/vectors.s
line something about 780 contains:
#ifdef CYGFUN_HAL_COMMON_KERNEL_SUPPORT
.extern cyg_scheduler_sched_lock
ldr r3,.cyg_scheduler_sched_lock
ldr r4,[r3]
add r4,r4,#1
str r4,[r3]
#endif
I inserted before this construction checkpoint, which just puts a
byte 0xCC (into my check buffer) each time.
Finally, buffer shows following info:
correct situation:
0xCC
0xAA - this was put by interrupt_end(), beginning
0x01 - scheduler lock at the beginning of interrupt_end()
0x00 - scheduler lock at the end of interrupt_end()
0xBB - this was put by interrupt_end(), end
incorrect and nothing more after that:
0xCC
0xCC
0xAA - this was put by interrupt_end(), beginning
0x02 - scheduler lock at the beginning of interrupt_end()
0x01 - scheduler lock at the end of interrupt_end()
0xBB - this was put by interrupt_end(), end
0xCC was put twice! How is it possible? Interrupts are disabled at
this stage. Am I right?
Sincerely yours
Yuriy Coureelo
------------------------
Engineer
Telecommunication Equipment Division
Micran Company
Tomsk, Russia
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