All of lore.kernel.org
 help / color / mirror / Atom feed
From: David Howells <dhowells@redhat.com>
To: linux-cachefs@redhat.com
Cc: dhowells@redhat.com, Anna Schumaker <anna.schumaker@netapp.com>,
	Steve French <sfrench@samba.org>,
	Dominique Martinet <asmadeus@codewreck.org>,
	Jeff Layton <jlayton@redhat.com>,
	David Wysochanski <dwysocha@redhat.com>,
	linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org,
	linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org,
	v9fs-developer@lists.sourceforge.net,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 05/12] fscache: Procfile to display cookies
Date: Mon, 21 Jun 2021 22:45:47 +0100	[thread overview]
Message-ID: <162431194785.2908479.786917990782538164.stgit@warthog.procyon.org.uk> (raw)
In-Reply-To: <162431188431.2908479.14031376932042135080.stgit@warthog.procyon.org.uk>

Add /proc/fs/fscache/cookies to display active cookies.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 fs/fscache/cookie.c     |  103 +++++++++++++++++++++++++++++++++++++++++++++++
 fs/fscache/internal.h   |    1 
 fs/fscache/proc.c       |    7 +++
 include/linux/fscache.h |    1 
 4 files changed, 112 insertions(+)

diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
index f2be98d2c64d..c7047544972b 100644
--- a/fs/fscache/cookie.c
+++ b/fs/fscache/cookie.c
@@ -19,6 +19,8 @@ static atomic_t fscache_object_debug_id = ATOMIC_INIT(0);
 
 #define fscache_cookie_hash_shift 15
 static struct hlist_bl_head fscache_cookie_hash[1 << fscache_cookie_hash_shift];
+static LIST_HEAD(fscache_cookies);
+static DEFINE_RWLOCK(fscache_cookies_lock);
 
 static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie,
 					    loff_t object_size);
@@ -65,6 +67,9 @@ void fscache_free_cookie(struct fscache_cookie *cookie)
 {
 	if (cookie) {
 		BUG_ON(!hlist_empty(&cookie->backing_objects));
+		write_lock(&fscache_cookies_lock);
+		list_del(&cookie->proc_link);
+		write_unlock(&fscache_cookies_lock);
 		if (cookie->aux_len > sizeof(cookie->inline_aux))
 			kfree(cookie->aux);
 		if (cookie->key_len > sizeof(cookie->inline_key))
@@ -192,6 +197,10 @@ struct fscache_cookie *fscache_alloc_cookie(
 	/* radix tree insertion won't use the preallocation pool unless it's
 	 * told it may not wait */
 	INIT_RADIX_TREE(&cookie->stores, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
+
+	write_lock(&fscache_cookies_lock);
+	list_add_tail(&cookie->proc_link, &fscache_cookies);
+	write_unlock(&fscache_cookies_lock);
 	return cookie;
 
 nomem:
@@ -969,3 +978,97 @@ int __fscache_check_consistency(struct fscache_cookie *cookie,
 	return -ESTALE;
 }
 EXPORT_SYMBOL(__fscache_check_consistency);
+
+/*
+ * Generate a list of extant cookies in /proc/fs/fscache/cookies
+ */
+static int fscache_cookies_seq_show(struct seq_file *m, void *v)
+{
+	struct fscache_cookie *cookie;
+	unsigned int keylen = 0, auxlen = 0;
+	char _type[3], *type;
+	u8 *p;
+
+	if (v == &fscache_cookies) {
+		seq_puts(m,
+			 "COOKIE   PARENT   USAGE CHILD ACT TY FL  DEF              NETFS_DATA\n"
+			 "======== ======== ===== ===== === == === ================ ==========\n"
+			 );
+		return 0;
+	}
+
+	cookie = list_entry(v, struct fscache_cookie, proc_link);
+
+	switch (cookie->type) {
+	case 0:
+		type = "IX";
+		break;
+	case 1:
+		type = "DT";
+		break;
+	default:
+		snprintf(_type, sizeof(_type), "%02u",
+			 cookie->type);
+		type = _type;
+		break;
+	}
+
+	seq_printf(m,
+		   "%08x %08x %5u %5u %3u %s %03lx %-16s %px",
+		   cookie->debug_id,
+		   cookie->parent ? cookie->parent->debug_id : 0,
+		   atomic_read(&cookie->usage),
+		   atomic_read(&cookie->n_children),
+		   atomic_read(&cookie->n_active),
+		   type,
+		   cookie->flags,
+		   cookie->def->name,
+		   cookie->netfs_data);
+
+	keylen = cookie->key_len;
+	auxlen = cookie->aux_len;
+
+	if (keylen > 0 || auxlen > 0) {
+		seq_puts(m, " ");
+		p = keylen <= sizeof(cookie->inline_key) ?
+			cookie->inline_key : cookie->key;
+		for (; keylen > 0; keylen--)
+			seq_printf(m, "%02x", *p++);
+		if (auxlen > 0) {
+			seq_puts(m, ", ");
+			p = auxlen <= sizeof(cookie->inline_aux) ?
+				cookie->inline_aux : cookie->aux;
+			for (; auxlen > 0; auxlen--)
+				seq_printf(m, "%02x", *p++);
+		}
+	}
+
+	seq_puts(m, "\n");
+	return 0;
+}
+
+static void *fscache_cookies_seq_start(struct seq_file *m, loff_t *_pos)
+	__acquires(fscache_cookies_lock)
+{
+	read_lock(&fscache_cookies_lock);
+	return seq_list_start_head(&fscache_cookies, *_pos);
+}
+
+static void *fscache_cookies_seq_next(struct seq_file *m, void *v, loff_t *_pos)
+{
+	return seq_list_next(v, &fscache_cookies, _pos);
+}
+
+static void fscache_cookies_seq_stop(struct seq_file *m, void *v)
+	__releases(rcu)
+{
+	read_unlock(&fscache_cookies_lock);
+}
+
+
+const struct seq_operations fscache_cookies_seq_ops = {
+	.start  = fscache_cookies_seq_start,
+	.next   = fscache_cookies_seq_next,
+	.stop   = fscache_cookies_seq_stop,
+	.show   = fscache_cookies_seq_show,
+};
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index c483863b740a..207a6bc81ca9 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -45,6 +45,7 @@ extern struct fscache_cache *fscache_select_cache_for_object(
  * cookie.c
  */
 extern struct kmem_cache *fscache_cookie_jar;
+extern const struct seq_operations fscache_cookies_seq_ops;
 
 extern void fscache_free_cookie(struct fscache_cookie *);
 extern struct fscache_cookie *fscache_alloc_cookie(struct fscache_cookie *,
diff --git a/fs/fscache/proc.c b/fs/fscache/proc.c
index 90a7bc22f7e1..da51fdfc8641 100644
--- a/fs/fscache/proc.c
+++ b/fs/fscache/proc.c
@@ -21,6 +21,10 @@ int __init fscache_proc_init(void)
 	if (!proc_mkdir("fs/fscache", NULL))
 		goto error_dir;
 
+	if (!proc_create_seq("fs/fscache/cookies", S_IFREG | 0444, NULL,
+			     &fscache_cookies_seq_ops))
+		goto error_cookies;
+
 #ifdef CONFIG_FSCACHE_STATS
 	if (!proc_create_single("fs/fscache/stats", S_IFREG | 0444, NULL,
 			fscache_stats_show))
@@ -53,6 +57,8 @@ int __init fscache_proc_init(void)
 	remove_proc_entry("fs/fscache/stats", NULL);
 error_stats:
 #endif
+	remove_proc_entry("fs/fscache/cookies", NULL);
+error_cookies:
 	remove_proc_entry("fs/fscache", NULL);
 error_dir:
 	_leave(" = -ENOMEM");
@@ -73,5 +79,6 @@ void fscache_proc_cleanup(void)
 #ifdef CONFIG_FSCACHE_STATS
 	remove_proc_entry("fs/fscache/stats", NULL);
 #endif
+	remove_proc_entry("fs/fscache/cookies", NULL);
 	remove_proc_entry("fs/fscache", NULL);
 }
diff --git a/include/linux/fscache.h b/include/linux/fscache.h
index ba58c427cf9a..ea61e54a6bc5 100644
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -133,6 +133,7 @@ struct fscache_cookie {
 	const struct fscache_cookie_def	*def;		/* definition */
 	struct fscache_cookie		*parent;	/* parent of this entry */
 	struct hlist_bl_node		hash_link;	/* Link in hash table */
+	struct list_head		proc_link;	/* Link in proc list */
 	void				*netfs_data;	/* back pointer to netfs */
 	struct radix_tree_root		stores;		/* pages to be stored on this cookie */
 #define FSCACHE_COOKIE_PENDING_TAG	0		/* pages tag: pending write to cache */



  parent reply	other threads:[~2021-06-21 21:46 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-21 21:44 [PATCH 00/12] fscache: Some prep work for fscache rewrite David Howells
2021-06-21 21:44 ` [PATCH 01/12] fscache: Select netfs stats if fscache stats are enabled David Howells
2021-06-21 21:45 ` [PATCH 02/12] netfs: Move cookie debug ID to struct netfs_cache_resources David Howells
2021-06-21 21:45 ` [PATCH 03/12] cachefiles: Use file_inode() rather than accessing ->f_inode David Howells
2021-06-21 21:45 ` [PATCH 04/12] fscache: Add a cookie debug ID and use that in traces David Howells
2021-06-21 21:45 ` David Howells [this message]
2021-06-21 21:45 ` [PATCH 06/12] fscache, cachefiles: Remove the histogram stuff David Howells
2021-06-21 21:46 ` [PATCH 07/12] fscache: Remove the object list procfile David Howells
2021-06-21 21:46 ` [PATCH 08/12] fscache: Change %p in format strings to something else David Howells
2021-06-21 21:46 ` [PATCH 09/12] cachefiles: " David Howells
2021-06-21 21:46 ` [PATCH 10/12] fscache: Fix cookie key hashing David Howells
2021-08-24 16:11   ` Jeff Layton
2021-08-25 14:04   ` David Howells
2021-06-21 21:47 ` [PATCH 11/12] fscache: Fix fscache_cookie_put() to not deref after dec David Howells
2021-08-24 14:24   ` Jeff Layton
2021-08-25 14:05   ` David Howells
2021-06-21 21:47 ` [PATCH 12/12] fscache: Use refcount_t for the cookie refcount instead of atomic_t David Howells
2021-08-24 14:25 ` [PATCH 00/12] fscache: Some prep work for fscache rewrite Jeff Layton
2021-08-27 12:31 ` [PATCH v2 04/12] fscache: Add a cookie debug ID and use that in traces David Howells
2021-08-27 12:49   ` [Linux-cachefs] " Marc Dionne

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=162431194785.2908479.786917990782538164.stgit@warthog.procyon.org.uk \
    --to=dhowells@redhat.com \
    --cc=anna.schumaker@netapp.com \
    --cc=asmadeus@codewreck.org \
    --cc=ceph-devel@vger.kernel.org \
    --cc=dwysocha@redhat.com \
    --cc=jlayton@redhat.com \
    --cc=linux-afs@lists.infradead.org \
    --cc=linux-cachefs@redhat.com \
    --cc=linux-cifs@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nfs@vger.kernel.org \
    --cc=sfrench@samba.org \
    --cc=v9fs-developer@lists.sourceforge.net \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.