Add a simple re-entrancy lock for tu_printf. #2653
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tlyu
reviewed
May 20, 2024
| int tu_printf_r(const char *format, ...) | ||
| { | ||
| // Simple re-entrancy lock, not safe for multi-core MCU | ||
| static volatile bool lock = false; |
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Even on a single core, volatile is not sufficient to prevent inconsistencies due to ISR execution interrupting another instance executing from user space. This needs an actual critical section, or similar.
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Could you make a real example with disassembly ?
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Describe the PR
Add a simple re-entrancy lock for TU_LOG, should resolve #2652 in most cases. An interlocked version is needed for multicore MCU.