Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Liam Howlett <liam.howlett@oracle.com>
To:     "maple-tree@lists.infradead.org" <maple-tree@lists.infradead.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
CC:     Song Liu <songliubraving@fb.com>,
        Davidlohr Bueso <dave@stgolabs.net>,
        "Paul E . McKenney" <paulmck@kernel.org>,
        Matthew Wilcox <willy@infradead.org>,
        Laurent Dufour <ldufour@linux.ibm.com>,
        David Rientjes <rientjes@google.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Rik van Riel <riel@surriel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Michel Lespinasse <walken.cr@gmail.com>,
        Liam Howlett <liam.howlett@oracle.com>
Subject: [PATCH 29/94] mm/mmap: Change find_vma() to use the maple tree
Thread-Topic: [PATCH 29/94] mm/mmap: Change find_vma() to use the maple tree
Thread-Index: AQHXPEQzL9yMZm5bA0iNsNMj/1H8hg==
Date:   Wed, 28 Apr 2021 15:36:04 +0000
Message-ID: <20210428153542.2814175-30-Liam.Howlett@Oracle.com>
References: <20210428153542.2814175-1-Liam.Howlett@Oracle.com>
In-Reply-To: <20210428153542.2814175-1-Liam.Howlett@Oracle.com>
Accept-Language: en-US
Content-Language: en-US
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-Network-Message-Id: 42fa3815-5052-42fa-f1a0-08d90a5b5607
X-MS-Exchange-CrossTenant-originalarrivaltime: 28 Apr 2021 15:36:04.3172
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: G+SoPRaa4enkeXJ3zE6qidRyt5D5bQEqdzslpBoJSKEShrbO7OKMtmDmQLB0DvC12fdl5a+UsnWRv409Plniog==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO1PR10MB4769
X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=9968 signatures=668683
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 malwarescore=0 mlxscore=0
 mlxlogscore=999 bulkscore=0 phishscore=0 spamscore=0 suspectscore=0
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104060000
 definitions=main-2104280101
X-Proofpoint-GUID: s_GK-xeoQrzaetHTp3_lFzfCWh3SfSn6
X-Proofpoint-ORIG-GUID: s_GK-xeoQrzaetHTp3_lFzfCWh3SfSn6
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Start using the maple tree to find VMA entries in an mm_struct.

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
---
 mm/mmap.c | 28 ++++++++++------------------
 1 file changed, 10 insertions(+), 18 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index 112be171b662..3a9a9aee2f63 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2483,10 +2483,16 @@ get_unmapped_area(struct file *file, unsigned long =
addr, unsigned long len,
=20
 EXPORT_SYMBOL(get_unmapped_area);
=20
-/* Look up the first VMA which satisfies  addr < vm_end,  NULL if none. */
+/**
+ * find_vma() - Find the VMA for a given address, or the next vma.
+ * @mm: The mm_struct to check
+ * @addr: The address
+ *
+ * Returns: The VMA associated with addr, or the next vma.
+ * May return %NULL in the case of no vma at addr or above.
+ */
 struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
 {
-	struct rb_node *rb_node;
 	struct vm_area_struct *vma;
=20
 	/* Check the cache first. */
@@ -2494,24 +2500,10 @@ struct vm_area_struct *find_vma(struct mm_struct *m=
m, unsigned long addr)
 	if (likely(vma))
 		return vma;
=20
-	rb_node =3D mm->mm_rb.rb_node;
-
-	while (rb_node) {
-		struct vm_area_struct *tmp;
-
-		tmp =3D rb_entry(rb_node, struct vm_area_struct, vm_rb);
-
-		if (tmp->vm_end > addr) {
-			vma =3D tmp;
-			if (tmp->vm_start <=3D addr)
-				break;
-			rb_node =3D rb_node->rb_left;
-		} else
-			rb_node =3D rb_node->rb_right;
-	}
-
+	vma =3D mt_find(&mm->mm_mt, &addr, ULONG_MAX);
 	if (vma)
 		vmacache_update(addr, vma);
+
 	return vma;
 }
 EXPORT_SYMBOL(find_vma);
--=20
2.30.2