does this behaviour of printf points to some problem in embedded linux's scheduler ( printf prints data to debug serial port , and consecutive read() calls in read_thread() are scheduled lately due to that ) ?
do the actual implementation of printf involves any kind of sleeps ?
kindly share necessary insight wrt above printf usage and driver ring buffer overrun .
I had encountered a similar problem, I think the problem is in 'printing to serial console' which is a slow process (transfer rate is very less compared to other i/o), serial I/O may not be able to keep up to the pace at which kernel logging happens. In my case, there was no such custom application writing to the console, instead the logging daemon itself was the culprit, some other drivers were not able to meet some timing requirements because of the heavy serial logging and my solution was to reduce the console logging using 'dmesg -n' option -- Thanks Sudheer