Driver supported smp linux kernel need use smp_wmb/smp_rmb, nor wmb/rmb?

David Yang david.yangshuai at gmail.com
Thu Aug 26 03:43:29 EDT 2010


Hello all,

Start with linux 2.6.33,  the DMA coherent buffers are mapped as Normal
Non-cacheable, so our drivers using dma_alloc_coherent() add the
barriers (e.g. wmb/rmb) to ensure that read/wirte coherence with
devices.

Now our drivers are stable at the non-smp linux 2.6.33,  if our driver
need support the smp linux 2.6.33, we need replace wmb()/rmb() to
smp_wmb()/smp_rmb()?


Thank for any help

David



More information about the linux-arm-kernel mailing list