multithreads

1.
thread1:
add to list
increment

thread2
add to list
increment

if the requirement is thread muxing ie 2 threads --> 1 thread processing
best implementation is
lock
add to list
if( increment ) {
release
}
else {
release
}
otherwise at cpu register level there should be an atomic xchange like cmd

any two register values modified complete state cannot be determined using single register

on the processing side ,with the above construct one variable can determine state
since incr and addlist is done atomic

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main process and deinit

deinit:
set flag
check if process increment flag is 0 else loop
proceed

process:
if flag do nothing
else carry on