On Tue, 2012-09-04 at 16:28 -0700, Andrew Morton wrote: > On Fri, 31 Aug 2012 18:55:59 -0600 > Shuah Khan <[email protected]> wrote: > > > Add kernel error message to track iotlb overflow buffer triggers to > > understand > > how often the overflow buffer gets used. > > > > Signed-off-by: Shuah Khan <[email protected]> > > --- > > lib/swiotlb.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/lib/swiotlb.c b/lib/swiotlb.c > > index 45bc1f8..597d7b9 100644 > > --- a/lib/swiotlb.c > > +++ b/lib/swiotlb.c > > @@ -682,6 +682,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct > > page *page, > > if (!map) { > > swiotlb_full(dev, size, dir, 1); > > map = io_tlb_overflow_buffer; > > + dev_err(dev, "SWIOTLB is full. Mapping overflow buffer.\n"); > > } > > > > dev_addr = swiotlb_virt_to_bus(dev, map); > > hm. I would view this as a developer-only debugging thing which > shouldn't be present in production code. Plus there's a potential that > some poor person will have his logs flooded with this message.
Yes. I agree. > > A more typical way of handling this would be to increment a stats > counter, accessible in procfs or debugfs. > Right. I will work on it. Maybe there is a way to combine this with dma-debug dma mapping error tracking work I am doing - will look into. -- Shuah -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
