]> Gitweb @ Texas Instruments - Open Source Git Repositories - git.TI.com/gitweb - rpmsg/rpmsg.git/commit
RDMA/core: not to set page dirty bit if it's already set.
authorQing Huang <qing.huang@oracle.com>
Thu, 18 May 2017 23:33:53 +0000 (16:33 -0700)
committerDoug Ledford <dledford@redhat.com>
Thu, 1 Jun 2017 21:20:12 +0000 (17:20 -0400)
commit53376fedb9da54c0d3b0bd3a6edcbeb681692909
tree74f8555562491ee89c8674d4b8ca052d48d12034
parentf937d93a9122d1510ca6e4bb8d860aedcf9408c3
RDMA/core: not to set page dirty bit if it's already set.

This change will optimize kernel memory deregistration operations.
__ib_umem_release() used to call set_page_dirty_lock() against every
writable page in its memory region. Its purpose is to keep data
synced between CPU and DMA device when swapping happens after mem
deregistration ops. Now we choose not to set page dirty bit if it's
already set by kernel prior to calling __ib_umem_release(). This
reduces memory deregistration time by half or even more when we ran
application simulation test program.

Signed-off-by: Qing Huang <qing.huang@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
drivers/infiniband/core/umem.c