>>> On 21.11.17 at 16:20, <kpraveen.l...@gmail.com> wrote: > From: Michel Lespinasse <wal...@google.com> > > Various minor optimizations in rb_erase(): > - Avoid multiple loading of node->__rb_parent_color when computing parent > and color information (possibly not in close sequence, as there might > be further branches in the algorithm) > - In the 1-child subcase of case 1, copy the __rb_parent_color field from > the erased node to the child instead of recomputing it from the desired > parent and color > - When searching for the erased node's successor, differentiate between > cases 2 and 3 based on whether any left links were followed. This avoids > a condition later down. > - In case 3, keep a pointer to the erased node's right child so we don't > have to refetch it later to adjust its parent. > - In the no-childs subcase of cases 2 and 3, place the rebalance assigment > last so that the compiler can remove the following if(rebalance) test. > > Also, added some comments to illustrate cases 2 and 3. > > Signed-off-by: Michel Lespinasse <wal...@google.com> > Acked-by: Rik van Riel <r...@redhat.com> > Cc: Peter Zijlstra <a.p.zijls...@chello.nl> > Cc: Andrea Arcangeli <aarca...@redhat.com> > Cc: David Woodhouse <dw...@infradead.org> > Signed-off-by: Andrew Morton <a...@linux-foundation.org> > Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> > [Linux commit 4f035ad67f4633c233cb3642711d49b4efc9c82d] > > Ported to Xen. > > Signed-off-by: Praveen Kumar <kpraveen.l...@gmail.com>
Acked-by: Jan Beulich <jbeul...@suse.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
