| Message ID | 1412875428.18196.3.camel@edumazet-glaptop2.roam.corp.google.com |
|---|---|
| State | Rejected, archived |
| Delegated to: | David Miller |
| Headers | show |
On Thu, 2014-10-09 at 10:23 -0700, Eric Dumazet wrote: > From: Eric Dumazet <edumazet@google.com> > > We allocate single page, compound_head() is not needed. > > We own the page, we can simply set page->_count to the > needed value instead of doing a locked addition. > > Signed-off-by: Eric Dumazet <edumazet@google.com> > --- > drivers/net/ethernet/sun/niu.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c > index 904fd1ab5f6e..ec2cd8a6d5bc 100644 > --- a/drivers/net/ethernet/sun/niu.c > +++ b/drivers/net/ethernet/sun/niu.c > @@ -3340,9 +3340,8 @@ static int niu_rbr_add_page(struct niu *np, struct rx_ring_info *rp, > } > > niu_hash_page(rp, page, addr); > - if (rp->rbr_blocks_per_page > 1) > - atomic_add(rp->rbr_blocks_per_page - 1, > - &compound_head(page)->_count); > + > + atomic_set(&page->_count, rp->rbr_blocks_per_page); > > for (i = 0; i < rp->rbr_blocks_per_page; i++) { > __le32 *rbr = &rp->rbr[start_index + i]; > Please disregard this patch. We need to fix all usages of atomic_set() on page->_count as they are racy. I'll send fixes. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c index 904fd1ab5f6e..ec2cd8a6d5bc 100644 --- a/drivers/net/ethernet/sun/niu.c +++ b/drivers/net/ethernet/sun/niu.c @@ -3340,9 +3340,8 @@ static int niu_rbr_add_page(struct niu *np, struct rx_ring_info *rp, } niu_hash_page(rp, page, addr); - if (rp->rbr_blocks_per_page > 1) - atomic_add(rp->rbr_blocks_per_page - 1, - &compound_head(page)->_count); + + atomic_set(&page->_count, rp->rbr_blocks_per_page); for (i = 0; i < rp->rbr_blocks_per_page; i++) { __le32 *rbr = &rp->rbr[start_index + i];