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  • [Cortex-A7][SMP][Cache]在多核上跑多任务会出现卡死问题

    运行环境:Linux

    现象:

    1. 只跑一个cpu时, 运行多个进程没有问题。

    2.开启SMP后, 四个CPU能正常启动,但是一旦跑多任务(后台多起几个程序),就会百分之百卡死,不进异常。

    3.开启SMP后,关闭L1/L2 Dcache后,按照同样方法跑多任务,就不会卡死。

    看起开好像是cache一致性问题,请教大家有没有什么好的想法和debug手段?

  • MOESI state encoding of Cortex-A7

    Hi,

    I am looking at Cortex-A7 TRM, In "Direct Access to Internal Memory"

    we can see several information regarding a cache line. Those are:

    1. Current data in cache

    2. its 4-bit MOESI state,

    3. Outer Memory Attribute

    4. its tag

    5. NS State.

    However…