Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Ajay Kaher <akaher@vmware.com>
To:     rostedt@goodmis.org, mhiramat@kernel.org, shuah@kernel.org
Cc:     linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org, chinglinyu@google.com,
        namit@vmware.com, srivatsa@csail.mit.edu, amakhalov@vmware.com,
        vsirnapalli@vmware.com, tkundu@vmware.com, er.ajay.kaher@gmail.com,
        Ajay Kaher <akaher@vmware.com>
Subject: [PATCH v3 08/10] eventfs: creating tracefs_inode_cache
Date:   Thu,  1 Jun 2023 14:30:11 +0530
Message-Id: <1685610013-33478-9-git-send-email-akaher@vmware.com>
In-Reply-To: <1685610013-33478-1-git-send-email-akaher@vmware.com>
References: <1685610013-33478-1-git-send-email-akaher@vmware.com>
Content-Type: text/plain
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?9swLPnYLmckwlLGPd464+QyDXHiqZ0Woz89N6n8nNJ48AH7Ntmh02zs0oTHG?=
 =?us-ascii?Q?r7qBi+8ErxdgaLGiwPryB1DIdbpd6F80T1Y0njHev2U7+oZmpa4H8h+6buwJ?=
 =?us-ascii?Q?pvabGh0/lenEzZReLrWQn1OZNdZoEMk0/SZJGVUF7Fm6eauZZ0YzbmH9o02L?=
 =?us-ascii?Q?L2qteIqL2u0YX1gE5AVG52X0fFRjytcqQVKDz4OMkYPfrGZSLBsaxF7OlkZl?=
 =?us-ascii?Q?xY7skVE86Uf4QnmrtbuY+547DxVt8z2N1NV5I1GW76ZXZH6oKKbwiZ6WH2jk?=
 =?us-ascii?Q?SQ66N89jUqjwd+oyh3yjekTpCT1v45ACx1wVuWS1lJVlhwc692cmBQpdIrHT?=
 =?us-ascii?Q?t2qjO/V5f/GFFS/U54rnIILeSbaEu6AQbbrP6YL91wclMCrE88Rr3ICTcesO?=
 =?us-ascii?Q?3PaIICbuOxP+OXrY5TuthpVwSI8f/a886HG9rYH2zANcjJ2lqoHgtb2SZ4vn?=
 =?us-ascii?Q?UHOd7jInjcTE8lIzxlL6+eGa76wgeNsde/qiCBvroo2ocbparnbTJjUE/8o2?=
 =?us-ascii?Q?CF/kZYw8iy7+zcovEcHsyAFLn7NdO7KsAf9FiaWeLUwxxhETNXqBJTAMx6zb?=
 =?us-ascii?Q?5BpmUJr9keiJJJczWpEegGmuxZXO4knsI4RH4mt8LHjaTqd8DbDyrXRKKJ0i?=
 =?us-ascii?Q?7Q/WQjfo9DmJ2Omhznz/naSStDg2yfDnWeHiyI+dDhipFmZwrJs6lW0GlVZq?=
 =?us-ascii?Q?J3t+Xo+LbW5/podq73qvBh3kA5CNwPolTrTiEqx4iS78gDia7ItFosHLDmKJ?=
 =?us-ascii?Q?nynYjMbpdbi7CaQULV4rsy2SfiRt7IMmQb/eQEtra0e0fTEoRoiOlndxSuxd?=
 =?us-ascii?Q?8n8EG/4np4bQabB7KCbBP6c0zzbub6CfRR8Fl9uYButqz384NY0l9//xXVz+?=
 =?us-ascii?Q?w5jdR0gImn0ZoytS2ZXNDCkXEvBuqOLgt5iHLam60DyEzm5BmQfnRkK+QLoO?=
 =?us-ascii?Q?ZDFO+sy3ejWJgpln52eg2lLhlbQzB6ECoghf58rQKYS4KwywrI3uXNKH8hss?=
 =?us-ascii?Q?1Ugvj/eiRrZq1wGX93aA8UIqG6d6+q396av2E3q3ZWo1b3LQ/2dJ106qQg1S?=
 =?us-ascii?Q?Wk7aPCjuWCdjgHhAR1kVAom6TeH1ZTLo4osdeGDqMKOwR7pbCCemdzfUwJYZ?=
 =?us-ascii?Q?Y6sNJpLycxCnDcFnueENo+1iLuexYYIJjyVHSAF+pyGIAYKgfcfz2RQOMfOS?=
 =?us-ascii?Q?OzV73F1OKtE+PuH1FvrGOBPJrAAE98vHAb+WwCYtdCBCA/rdPT/9r5voHQEY?=
 =?us-ascii?Q?RZAJYK2Zy2CJzeJiLphSTHDh6bv9ro4BV3WekwiwCaO7f1AISp1b1f3Ng0LP?=
 =?us-ascii?Q?WAe31QDGl3hRToqf9Vm+nPeRUPIiA5m/D3TzuEKaAeUctCqS2L96v8bFaDOz?=
 =?us-ascii?Q?4U13Sqzf6DVqiXlqUD8e1njso8KvyH1Sr94aaPmigJQL6+CpD5m7ZRZ6pbBM?=
 =?us-ascii?Q?EaOPb0wErffoV45K27VOUWR5CcL2xMUWOuKo7BhrBWhXfGmhLitVxGYN5Ut9?=
 =?us-ascii?Q?wCD82QprSE1XP/o/kyKYX4J0tILQzVshPMu78nX2QBdDnc+OzMbNOqZqNnko?=
 =?us-ascii?Q?M16hfpk8t059RJIwUvn2CsWA1tm3jV69SOQ/HwGb?=
X-OriginatorOrg: vmware.com
X-MS-Exchange-CrossTenant-Network-Message-Id: c32eaa0f-46b1-439d-92ce-08db627ec010
X-MS-Exchange-CrossTenant-AuthSource: PH0PR05MB8703.namprd05.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Jun 2023 09:01:13.2165
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: USMoihawouqkpeblLsjobu/le3T4AKOXso5mKDAe/vMfayRrAnYJ3ZOYfI+hvd3V9DV0MMOtrSmHXgjxnQaePA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR05MB8617
X-Spam-Status: No, score=-2.3 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,
        DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,
        SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham
        autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Creating tracefs_inode_cache which is a cache of tracefs_inode.
Adding helping functions:
tracefs_alloc_inode()
tracefs_free_inode()

Signed-off-by: Ajay Kaher <akaher@vmware.com>
Co-developed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Ching-lin Yu <chinglinyu@google.com>
---
 fs/tracefs/inode.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
index 66c4df734..76820d3e9 100644
--- a/fs/tracefs/inode.c
+++ b/fs/tracefs/inode.c
@@ -24,11 +24,30 @@
 #include "internal.h"
 
 #define TRACEFS_DEFAULT_MODE	0700
+static struct kmem_cache *tracefs_inode_cachep __ro_after_init;
 
 static struct vfsmount *tracefs_mount;
 static int tracefs_mount_count;
 static bool tracefs_registered;
 
+static struct inode *tracefs_alloc_inode(struct super_block *sb)
+{
+	struct tracefs_inode *ti;
+
+	ti = kmem_cache_alloc(tracefs_inode_cachep, GFP_KERNEL);
+	if (!ti)
+		return NULL;
+
+	ti->flags = 0;
+
+	return &ti->vfs_inode;
+}
+
+static void tracefs_free_inode(struct inode *inode)
+{
+	kmem_cache_free(tracefs_inode_cachep, get_tracefs(inode));
+}
+
 static ssize_t default_read_file(struct file *file, char __user *buf,
 				 size_t count, loff_t *ppos)
 {
@@ -347,6 +366,9 @@ static int tracefs_show_options(struct seq_file *m, struct dentry *root)
 }
 
 static const struct super_operations tracefs_super_operations = {
+	.alloc_inode    = tracefs_alloc_inode,
+	.free_inode     = tracefs_free_inode,
+	.drop_inode     = generic_delete_inode,
 	.statfs		= simple_statfs,
 	.remount_fs	= tracefs_remount,
 	.show_options	= tracefs_show_options,
@@ -676,10 +698,26 @@ bool tracefs_initialized(void)
 	return tracefs_registered;
 }
 
+static void init_once(void *foo)
+{
+	struct tracefs_inode *ti = (struct tracefs_inode *) foo;
+
+	inode_init_once(&ti->vfs_inode);
+}
+
 static int __init tracefs_init(void)
 {
 	int retval;
 
+	tracefs_inode_cachep = kmem_cache_create("tracefs_inode_cache",
+						 sizeof(struct tracefs_inode),
+						 0, (SLAB_RECLAIM_ACCOUNT|
+						     SLAB_MEM_SPREAD|
+						     SLAB_ACCOUNT),
+						 init_once);
+	if (!tracefs_inode_cachep)
+		return -ENOMEM;
+
 	retval = sysfs_create_mount_point(kernel_kobj, "tracing");
 	if (retval)
 		return -EINVAL;
-- 
2.40.0