Nördnytt! 🤓The Lost Atomic Update on Loongson CPU
jia.je - 95 poäng - 5 kommentarer - 222481 sekunder sedan
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- TazeTSchnitzel - 15415 sekunder sedan> The fix is to set bit 13 of MCSR24 to 1. MCSR24 is an internal CSR whose function is not described in the manual. After setting this bit, the lost update no longer occurs. Testing showed the performance loss is very small: single-core performance is unaffected, and multi-core performance drops only slightly.
Presumably this is a so-called “chicken bit”.