acct: get rid of acct_list
Put these suckers on per-vfsmount and per-superblock lists instead.
Note: right now it's still acct_lock for everything, but that's
going to change.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/kernel/acct.c b/kernel/acct.c
index 019f012..21fbb3c 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -59,6 +59,7 @@
#include <asm/div64.h>
#include <linux/blkdev.h> /* sector_div */
#include <linux/pid_namespace.h>
+#include <../fs/mount.h> /* will go away when we refactor */
/*
* These constants control the amount of freespace that suspend and
@@ -79,16 +80,16 @@
struct bsd_acct_struct {
long count;
+ struct hlist_node s_list;
+ struct hlist_node m_list;
struct mutex lock;
int active;
unsigned long needcheck;
struct file *file;
struct pid_namespace *ns;
- struct list_head list;
};
static DEFINE_SPINLOCK(acct_lock);
-static LIST_HEAD(acct_list);
/*
* Check the amount of free space and suspend/resume accordingly.
@@ -133,25 +134,33 @@
spin_unlock(&acct_lock);
}
-static struct bsd_acct_struct *acct_get(struct bsd_acct_struct **p)
+static struct bsd_acct_struct *__acct_get(struct bsd_acct_struct *res)
+{
+ res->count++;
+ spin_unlock(&acct_lock);
+ mutex_lock(&res->lock);
+ if (!res->ns) {
+ mutex_unlock(&res->lock);
+ spin_lock(&acct_lock);
+ if (!--res->count)
+ kfree(res);
+ return NULL;
+ }
+ return res;
+}
+
+static struct bsd_acct_struct *acct_get(struct pid_namespace *ns)
{
struct bsd_acct_struct *res;
spin_lock(&acct_lock);
again:
- res = *p;
- if (res)
- res->count++;
- spin_unlock(&acct_lock);
- if (res) {
- mutex_lock(&res->lock);
- if (!res->ns) {
- mutex_unlock(&res->lock);
- spin_lock(&acct_lock);
- if (!--res->count)
- kfree(res);
- goto again;
- }
+ if (!ns->bacct) {
+ spin_unlock(&acct_lock);
+ return NULL;
}
+ res = __acct_get(ns->bacct);
+ if (!res)
+ goto again;
return res;
}
@@ -162,7 +171,8 @@
struct file *file = acct->file;
struct pid_namespace *ns = acct->ns;
spin_lock(&acct_lock);
- list_del(&acct->list);
+ hlist_del(&acct->m_list);
+ hlist_del(&acct->s_list);
mnt_unpin(file->f_path.mnt);
spin_unlock(&acct_lock);
do_acct_process(acct);
@@ -170,8 +180,10 @@
spin_lock(&acct_lock);
ns->bacct = new;
if (new) {
- mnt_pin(new->file->f_path.mnt);
- list_add(&new->list, &acct_list);
+ struct vfsmount *m = new->file->f_path.mnt;
+ mnt_pin(m);
+ hlist_add_head(&new->s_list, &m->mnt_sb->s_pins);
+ hlist_add_head(&new->m_list, &real_mount(m)->mnt_pins);
}
acct->ns = NULL;
mutex_unlock(&acct->lock);
@@ -218,14 +230,15 @@
mutex_init(&acct->lock);
mnt = file->f_path.mnt;
- old = acct_get(&ns->bacct);
+ old = acct_get(ns);
if (old) {
acct_kill(old, acct);
} else {
spin_lock(&acct_lock);
ns->bacct = acct;
mnt_pin(mnt);
- list_add(&acct->list, &acct_list);
+ hlist_add_head(&acct->s_list, &mnt->mnt_sb->s_pins);
+ hlist_add_head(&acct->m_list, &real_mount(mnt)->mnt_pins);
spin_unlock(&acct_lock);
}
mntput(mnt); /* it's pinned, now give up active reference */
@@ -261,79 +274,41 @@
mutex_unlock(&acct_on_mutex);
putname(tmp);
} else {
- acct_kill(acct_get(&task_active_pid_ns(current)->bacct), NULL);
+ acct_kill(acct_get(task_active_pid_ns(current)), NULL);
}
return error;
}
-/**
- * acct_auto_close - turn off a filesystem's accounting if it is on
- * @m: vfsmount being shut down
- *
- * If the accounting is turned on for a file in the subtree pointed to
- * to by m, turn accounting off. Done when m is about to die.
- */
-void acct_auto_close_mnt(struct vfsmount *m)
+void acct_auto_close_mnt(struct hlist_head *list)
{
- struct bsd_acct_struct *acct;
-
- spin_lock(&acct_lock);
-restart:
- list_for_each_entry(acct, &acct_list, list)
- if (acct->file->f_path.mnt == m) {
- acct->count++;
- spin_unlock(&acct_lock);
- mutex_lock(&acct->lock);
- if (!acct->ns) {
- mutex_unlock(&acct->lock);
- spin_lock(&acct_lock);
- if (!--acct->count)
- kfree(acct);
- goto restart;
- }
- acct_kill(acct, NULL);
- spin_lock(&acct_lock);
- goto restart;
- }
+ while (1) {
+ spin_lock(&acct_lock);
+ if (!list->first)
+ break;
+ acct_kill(__acct_get(hlist_entry(list->first,
+ struct bsd_acct_struct,
+ m_list)), NULL);
+ }
spin_unlock(&acct_lock);
}
-/**
- * acct_auto_close - turn off a filesystem's accounting if it is on
- * @sb: super block for the filesystem
- *
- * If the accounting is turned on for a file in the filesystem pointed
- * to by sb, turn accounting off.
- */
-void acct_auto_close(struct super_block *sb)
+void acct_auto_close(struct hlist_head *list)
{
- struct bsd_acct_struct *acct;
-
- spin_lock(&acct_lock);
-restart:
- list_for_each_entry(acct, &acct_list, list)
- if (acct->file->f_path.dentry->d_sb == sb) {
- acct->count++;
- spin_unlock(&acct_lock);
- mutex_lock(&acct->lock);
- if (!acct->ns) {
- mutex_unlock(&acct->lock);
- spin_lock(&acct_lock);
- if (!--acct->count)
- kfree(acct);
- goto restart;
- }
- acct_kill(acct, NULL);
- spin_lock(&acct_lock);
- goto restart;
- }
+ while (1) {
+ spin_lock(&acct_lock);
+ if (!list->first)
+ break;
+ acct_kill(__acct_get(hlist_entry(list->first,
+ struct bsd_acct_struct,
+ s_list)), NULL);
+ }
spin_unlock(&acct_lock);
}
void acct_exit_ns(struct pid_namespace *ns)
{
- acct_kill(acct_get(&ns->bacct), NULL);
+ acct_kill(acct_get(ns), NULL);
}
/*
@@ -602,7 +577,7 @@
static void slow_acct_process(struct pid_namespace *ns)
{
for ( ; ns; ns = ns->parent) {
- struct bsd_acct_struct *acct = acct_get(&ns->bacct);
+ struct bsd_acct_struct *acct = acct_get(ns);
if (acct) {
do_acct_process(acct);
mutex_unlock(&acct->lock);