From: Maarten Lankhorst Date: Tue, 1 Jul 2014 10:58:00 +0000 (+0200) Subject: reservation: add suppport for read-only access using rcu X-Git-Tag: omap-for-v3.17/fixes-against-rc2~167^2~19 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3c3b177a9369b26890ced004867fb32708e8ef5b;p=pandora-kernel.git reservation: add suppport for read-only access using rcu This adds some extra functions to deal with rcu. reservation_object_get_fences_rcu() will obtain the list of shared and exclusive fences without obtaining the ww_mutex. reservation_object_wait_timeout_rcu() will wait on all fences of the reservation_object, without obtaining the ww_mutex. reservation_object_test_signaled_rcu() will test if all fences of the reservation_object are signaled without using the ww_mutex. reservation_object_get_excl and reservation_object_get_list require the reservation object to be held, updating requires write_seqcount_begin/end. If only the exclusive fence is needed, rcu_dereference followed by fence_get_rcu can be used, if the shared fences are needed it's recommended to use the supplied functions. Signed-off-by: Maarten Lankhorst Acked-by: Sumit Semwal Acked-by: Daniel Vetter Reviewed-By: Thomas Hellstrom Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed