mm: replace vma prio_tree with an interval tree

Implement an interval tree as a replacement for the VMA prio_tree.  The
algorithms are similar to lib/interval_tree.c; however that code can't be
directly reused as the interval endpoints are not explicitly stored in the
VMA.  So instead, the common algorithm is moved into a template and the
details (node type, how to get interval endpoints from the node, etc) are
filled in using the C preprocessor.

Once the interval tree functions are available, using them as a
replacement to the VMA prio tree is a relatively simple, mechanical job.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 2 deletions

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index a6e2141a6610..c38a6257d082 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -431,7 +431,6 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
 {
         struct vm_area_struct *vma;
         struct task_struct *tsk;
-        struct prio_tree_iter iter;
         struct address_space *mapping = page->mapping;
 
         mutex_lock(&mapping->i_mmap_mutex);
@@ -442,7 +441,7 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
                 if (!task_early_kill(tsk))
                         continue;
 
-                vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff,
+                vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff,
                                       pgoff) {
                         /*
                          * Send early kill signal to tasks where a vma covers