On Wed, May 27, 2015 at 09:19:04AM -0600, Toshi Kani wrote: > The pmem driver maps NVDIMM with ioremap_nocache() as we cannot > write back the contents of the CPU caches in case of a crash. > > This patch changes to use ioremap_wt(), which provides uncached > writes but cached reads, for improving read performance. > > Signed-off-by: Toshi Kani <toshi.k...@hp.com> > --- > drivers/block/pmem.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c > index eabf4a8..095dfaa 100644 > --- a/drivers/block/pmem.c > +++ b/drivers/block/pmem.c > @@ -139,11 +139,11 @@ static struct pmem_device *pmem_alloc(struct device > *dev, struct resource *res) > } > > /* > - * Map the memory as non-cachable, as we can't write back the contents > + * Map the memory as write-through, as we can't write back the contents > * of the CPU caches in case of a crash. > */ > err = -ENOMEM; > - pmem->virt_addr = ioremap_nocache(pmem->phys_addr, pmem->size); > + pmem->virt_addr = ioremap_wt(pmem->phys_addr, pmem->size); > if (!pmem->virt_addr) > goto out_release_region;
Dan, Ross, what about this one? ACK to pick it up as a temporary solution? -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/