radix-tree: delete radix_tree_range_tag_if_tagged()
This is an exceptionally complicated function with just one caller
(tag_pages_for_writeback). We devote a large portion of the runtime of
the test suite to testing this one function which has one caller. By
introducing the new function radix_tree_iter_tag_set(), we can eliminate
all of the complexity while keeping the performance. The caller can now
use a fairly standard radix_tree_for_each() loop, and it doesn't need to
worry about tricksy things like 'start' wrapping.
The test suite continues to spend a large amount of time investigating
this function, but now it's testing the underlying primitives such as
radix_tree_iter_resume() and the radix_tree_for_each_tagged() iterator
which are also used by other parts of the kernel.
Link: http://lkml.kernel.org/r/1480369871-5271-57-git-send-email-mawilcox@linuxonhyperv.com
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/tools/testing/radix-tree/regression2.c b/tools/testing/radix-tree/regression2.c
index 63bf347..a41325d 100644
--- a/tools/testing/radix-tree/regression2.c
+++ b/tools/testing/radix-tree/regression2.c
@@ -50,6 +50,7 @@
#include <stdio.h>
#include "regression.h"
+#include "test.h"
#define PAGECACHE_TAG_DIRTY 0
#define PAGECACHE_TAG_WRITEBACK 1
@@ -90,7 +91,7 @@ void regression2_test(void)
/* 1. */
start = 0;
end = max_slots - 2;
- radix_tree_range_tag_if_tagged(&mt_tree, &start, end, 1,
+ tag_tagged_items(&mt_tree, NULL, start, end, 1,
PAGECACHE_TAG_DIRTY, PAGECACHE_TAG_TOWRITE);
/* 2. */