linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Liam R. Howlett" <Liam.Howlett@oracle.com>
To: maple-tree@lists.infradead.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Stable@vger.kernel.org, zhangpeng.00@bytedance.com,
	snild@sony.com
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Subject: [PATCH v2 2/2] test_maple_tree: Add more testing for mas_empty_area()
Date: Tue,  7 Mar 2023 13:02:47 -0500	[thread overview]
Message-ID: <20230307180247.2220303-3-Liam.Howlett@oracle.com> (raw)
In-Reply-To: <20230307180247.2220303-1-Liam.Howlett@oracle.com>

Test robust filling of an entire area of the tree, then test one beyond.
This is to test the walking back up the tree at the end of nodes and
error condition.  Test inspired by the reproducer code provided by Snild
Dolkow.

The last test in the function tests for the case of a corrupted maple
state caused by the incorrect limits set during mas_skip_node().  There
needs to be a gap in the second last child and last child, but the
search must rule out the second last child's gap.  This would avoid
correcting the maple state to the correct max limit and return an error.

Cc: Snild Dolkow <snild@sony.com>
Link: https://lore.kernel.org/linux-mm/cb8dc31a-fef2-1d09-f133-e9f7b9f9e77a@sony.com/
Cc: <Stable@vger.kernel.org>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Fixes: e15e06a83923 ("lib/test_maple_tree: add testing for maple tree")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
 lib/test_maple_tree.c | 48 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c
index 3d19b1f78d71..f1db333270e9 100644
--- a/lib/test_maple_tree.c
+++ b/lib/test_maple_tree.c
@@ -2670,6 +2670,49 @@ static noinline void check_empty_area_window(struct maple_tree *mt)
 	rcu_read_unlock();
 }
 
+static noinline void check_empty_area_fill(struct maple_tree *mt)
+{
+	const unsigned long max = 0x25D78000;
+	unsigned long size;
+	int loop, shift;
+	MA_STATE(mas, mt, 0, 0);
+
+	mt_set_non_kernel(99999);
+	for (shift = 12; shift <= 16; shift++) {
+		loop = 5000;
+		size = 1 << shift;
+		while (loop--) {
+			mas_set(&mas, 0);
+			mas_lock(&mas);
+			MT_BUG_ON(mt, mas_empty_area(&mas, 0, max, size) != 0);
+			MT_BUG_ON(mt, mas.last != mas.index + size - 1);
+			mas_store_gfp(&mas, (void *)size, GFP_KERNEL);
+			mas_unlock(&mas);
+			mas_reset(&mas);
+		}
+	}
+
+	/* No space left. */
+	size = 0x1000;
+	rcu_read_lock();
+	MT_BUG_ON(mt, mas_empty_area(&mas, 0, max, size) != -EBUSY);
+	rcu_read_unlock();
+
+	/* Fill a depth 3 node to the maximum */
+	for (unsigned long i = 629440511; i <= 629440800; i += 6)
+		mtree_store_range(mt, i, i + 5, (void *)i, GFP_KERNEL);
+	/* Make space in the second-last depth 4 node */
+	mtree_erase(mt, 631668735);
+	/* Make space in the last depth 4 node */
+	mtree_erase(mt, 629506047);
+	mas_reset(&mas);
+	/* Search from just after the gap in the second-last depth 4 */
+	rcu_read_lock();
+	MT_BUG_ON(mt, mas_empty_area(&mas, 629506048, 690000000, 0x5000) != 0);
+	rcu_read_unlock();
+	mt_set_non_kernel(0);
+}
+
 static DEFINE_MTREE(tree);
 static int maple_tree_seed(void)
 {
@@ -2926,6 +2969,11 @@ static int maple_tree_seed(void)
 	check_empty_area_window(&tree);
 	mtree_destroy(&tree);
 
+	mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
+	check_empty_area_fill(&tree);
+	mtree_destroy(&tree);
+
+
 #if defined(BENCH)
 skip:
 #endif
-- 
2.39.2


      parent reply	other threads:[~2023-03-07 18:09 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-07 18:02 [PATCH v2 0/2] Fix mas_skip_node() for mas_empty_area() Liam R. Howlett
2023-03-07 18:02 ` [PATCH v2 1/2] maple_tree: Fix mas_skip_node() end slot detection Liam R. Howlett
2023-03-08  8:49   ` Snild Dolkow
2023-03-07 18:02 ` Liam R. Howlett [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230307180247.2220303-3-Liam.Howlett@oracle.com \
    --to=liam.howlett@oracle.com \
    --cc=Stable@vger.kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=maple-tree@lists.infradead.org \
    --cc=snild@sony.com \
    --cc=zhangpeng.00@bytedance.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).