• Here is the events that cause the Store buffer to drain on x86 CPUs

    From Wisdom90@21:1/5 to All on Mon Jan 20 10:20:01 2020

    Here is the events that cause the Store buffer to drain on x86 CPUs, in
    Section 11.10 of Volume 3 of the Intel SW Developer's Guide, the
    following list of store-buffer-draining events is included:

    - Generation of an Exception and/or Interrupt
    - Execution of a serializing instruction (CPUID, IRET, and RSM are the
    only non-privileged serializing instructions)
    - Execution of an I/O instruction
    - Execution of a LOCK operation
    - Execution of the BINIT operation (an external reset operation using
    the BINIT pin)
    - Execution of an SFENCE instruction
    - Execution of an MFENCE instruction

    So as you are noticing that the LOCK instruction also causes the store
    buffer to drain, and i am using it in my parallel software projects.

    Also read this about the store buffer:

    "However under x86-TSO, the stores are cached in the store buffers,
    a load consult only shared memory and the store buffer of the given
    thread, wich means it can load data from memory and ignore values from
    the other thread."

    Read more here:


    Thank you,
    Amine Moulay Ramdane.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)