]> git.baikalelectronics.ru Git - kernel.git/commit
IB/core: dma unmap optimizations
authorGuy Shapiro <guysh@mellanox.com>
Wed, 15 Apr 2015 15:17:57 +0000 (18:17 +0300)
committerDoug Ledford <dledford@redhat.com>
Tue, 5 May 2015 13:18:02 +0000 (09:18 -0400)
commit2817bff0523edfaa1a698f8bbdeffd2b029bb0f9
tree13383cd4f5442a70bff01f0f55d8007fcb03002a
parent321d5d7f53c08d6e85c47aad1a3de1357601df24
IB/core: dma unmap optimizations

While unmapping an ODP writable page, the dirty bit of the page is set. In
order to do so, the head of the compound page is found.
Currently, the compound head is found even on non-writable pages, where it is
never used, leading to unnecessary cpu barrier that impacts performance.

This patch moves the search for the compound head to be done only when needed.

Signed-off-by: Guy Shapiro <guysh@mellanox.com>
Acked-by: Shachar Raindel <raindel@mellanox.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
drivers/infiniband/core/umem_odp.c