• Locked Locked
  • Replies 4 replies
  • Subscribers 119 subscribers
  • Views 3337 views
  • Users 0 members are here
2025 survey

We are running a survey to help us improve the experience for all of our members. If you see the survey appear, please take the time to tell us about your experience if you can.

Options
Related
How was your experience today?
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

memory barrier

mosfet mosfet
Note: This was originally posted on 18th January 2010 at http://forums.arm.com

Hi,

On x86/win architecture there is a function called MemoryBarrier that prevents the CPU from re-ordering read/write operations.
Is there something like that on arm architecture ?

// x86

FORCEINLINE VOID
MemoryBarrier (VOID)
{
    LONG Barrier;
    __asm {
        xchg Barrier, eax
    }
}
Parents
  • Note: This was originally posted on 20th January 2010 at http://forums.arm.com

    Older generations of ARM processors (e.g. ARM7TDMI) does not have memory barrier instructions.
    Newer ARM processors (all Cortex-A, Cortex-R and Cortex-M processors) have memory barrier instructions


    Thanks for the info...

    By looking at the example of x86
    Do you think SWP or SWPB does
    the same thing XCHG does on x86 ?

    As SWP blocks the SystemBus, I think
    the core should write any outstanding write
    ops before executing this instruction, any thought ?
Reply
  • Note: This was originally posted on 20th January 2010 at http://forums.arm.com

    Older generations of ARM processors (e.g. ARM7TDMI) does not have memory barrier instructions.
    Newer ARM processors (all Cortex-A, Cortex-R and Cortex-M processors) have memory barrier instructions


    Thanks for the info...

    By looking at the example of x86
    Do you think SWP or SWPB does
    the same thing XCHG does on x86 ?

    As SWP blocks the SystemBus, I think
    the core should write any outstanding write
    ops before executing this instruction, any thought ?
Children
No data