+ radix-tree-test-suite-track-preempt_count.patch added to -mm tree

+ radix-tree-test-suite-track-preempt_count.patch added to -mm tree

[akpm]

The patch titled
     Subject: radix tree test suite: track preempt_count
has been added to the -mm tree.  Its filename is
     radix-tree-test-suite-track-preempt_count.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/radix-tree-test-suite-track-preempt_count.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/radix-tree-test-suite-track-preempt_count.patch

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*** Remember to use Documentation/SubmitChecklist when testing your code ***

The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: Matthew Wilcox <willy@infradead.org>
Subject: radix tree test suite: track preempt_count

Rather than simply NOP out preempt_enable() and preempt_disable(), keep
track of preempt_count and display it regularly in case either the test
suite or the code under test is forgetting to balance the enables &
disables.  Only found a test-case that was forgetting to re-enable
preemption, but it's a possibility worth checking.

Link: http://lkml.kernel.org/r/1480369871-5271-39-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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/radix-tree/linux.c         |    1 
 tools/testing/radix-tree/linux/preempt.h |    6 ++--
 tools/testing/radix-tree/main.c          |   30 ++++++++++++++-------
 3 files changed, 24 insertions(+), 13 deletions(-)

diff -puN tools/testing/radix-tree/linux.c~radix-tree-test-suite-track-preempt_count tools/testing/radix-tree/linux.c
--- a/tools/testing/radix-tree/linux.c~radix-tree-test-suite-track-preempt_count
+++ a/tools/testing/radix-tree/linux.c
@@ -9,6 +9,7 @@
 #include <urcu/uatomic.h>
 
 int nr_allocated;
+int preempt_count;
 
 void *mempool_alloc(mempool_t *pool, int gfp_mask)
 {
diff -puN tools/testing/radix-tree/linux/preempt.h~radix-tree-test-suite-track-preempt_count tools/testing/radix-tree/linux/preempt.h
--- a/tools/testing/radix-tree/linux/preempt.h~radix-tree-test-suite-track-preempt_count
+++ a/tools/testing/radix-tree/linux/preempt.h
@@ -1,4 +1,4 @@
-/* */
+extern int preempt_count;
 
-#define preempt_disable() do { } while (0)
-#define preempt_enable() do { } while (0)
+#define preempt_disable()	uatomic_inc(&preempt_count)
+#define preempt_enable()	uatomic_dec(&preempt_count)
diff -puN tools/testing/radix-tree/main.c~radix-tree-test-suite-track-preempt_count tools/testing/radix-tree/main.c
--- a/tools/testing/radix-tree/main.c~radix-tree-test-suite-track-preempt_count
+++ a/tools/testing/radix-tree/main.c
@@ -293,27 +293,36 @@ static void single_thread_tests(bool lon
 {
 	int i;
 
-	printf("starting single_thread_tests: %d allocated\n", nr_allocated);
+	printf("starting single_thread_tests: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	multiorder_checks();
-	printf("after multiorder_check: %d allocated\n", nr_allocated);
+	printf("after multiorder_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	locate_check();
-	printf("after locate_check: %d allocated\n", nr_allocated);
+	printf("after locate_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	tag_check();
-	printf("after tag_check: %d allocated\n", nr_allocated);
+	printf("after tag_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	gang_check();
-	printf("after gang_check: %d allocated\n", nr_allocated);
+	printf("after gang_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	add_and_check();
-	printf("after add_and_check: %d allocated\n", nr_allocated);
+	printf("after add_and_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	dynamic_height_check();
-	printf("after dynamic_height_check: %d allocated\n", nr_allocated);
+	printf("after dynamic_height_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	big_gang_check(long_run);
-	printf("after big_gang_check: %d allocated\n", nr_allocated);
+	printf("after big_gang_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	for (i = 0; i < (long_run ? 2000 : 3); i++) {
 		copy_tag_check();
 		printf("%d ", i);
 		fflush(stdout);
 	}
-	printf("after copy_tag_check: %d allocated\n", nr_allocated);
+	printf("after copy_tag_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 }
 
 int main(int argc, char **argv)
@@ -336,7 +345,8 @@ int main(int argc, char **argv)
 	single_thread_tests(long_run);
 
 	sleep(1);
-	printf("after sleep(1): %d allocated\n", nr_allocated);
+	printf("after sleep(1): %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	rcu_unregister_thread();
 
 	exit(0);
_

Patches currently in -mm which might be from willy@infradead.org are

radix-tree-test-suite-track-preempt_count.patch
radix-tree-test-suite-free-preallocated-nodes.patch
radix-tree-test-suite-make-runs-more-reproducible.patch
radix-tree-move-rcu_head-into-a-union-with-private_list.patch
radix-tree-improve-dump-output.patch