[Devel] [PATCH rh7] ve: Kill ve_list_head and ve_struct::ve_list

Kirill Tkhai ktkhai at odin.com
Thu Sep 24 08:11:26 PDT 2015


Since we use ve_idr layer to reserve a id for a ve,
and since a ve is linked there, using of ve_list_head
just for linking VEs becomes redundant.

This patch replaces ve_list_head in the places, we iterate
thru VEs list, with ve_idr mechanish, and kills the
duplicate manner.

Signed-off-by: Kirill Tkhai <ktkhai at odin.com>
---
 include/linux/ve.h       |    2 --
 include/linux/ve_proto.h |    3 +--
 kernel/ve/ve.c           |   10 +++-------
 kernel/ve/vecalls.c      |   38 +++++++++++++++-----------------------
 kernel/ve/vzlist.c       |    4 ++--
 kernel/ve/vzstat.c       |    4 +++-
 scripts/kconfig/conf     |  Bin
 6 files changed, 24 insertions(+), 37 deletions(-)

diff --git a/include/linux/ve.h b/include/linux/ve.h
index 10c150a..54091a1 100644
--- a/include/linux/ve.h
+++ b/include/linux/ve.h
@@ -37,8 +37,6 @@ struct ve_struct {
 
 	const char		*ve_name;
 
-	struct list_head	ve_list;
-
 	envid_t			veid;
 	bool			legacy;	/* created using the legacy API
 					   (vzctl ioctl - see do_env_create) */
diff --git a/include/linux/ve_proto.h b/include/linux/ve_proto.h
index 0f5898e..d67341e 100644
--- a/include/linux/ve_proto.h
+++ b/include/linux/ve_proto.h
@@ -49,10 +49,9 @@ void vzmon_unregister_veaddr_print_cb(ve_seq_print_t);
 int venet_init(void);
 #endif
 
-extern struct list_head ve_list_head;
-#define for_each_ve(ve)	list_for_each_entry((ve), &ve_list_head, ve_list)
 extern struct mutex ve_list_lock;
 extern struct ve_struct *get_ve_by_id(envid_t);
+extern struct idr ve_idr;
 extern struct cgroup *ve_cgroup_open(struct cgroup *root, int flags, envid_t veid);
 extern int ve_cgroup_remove(struct cgroup *root, envid_t veid);
 
diff --git a/kernel/ve/ve.c b/kernel/ve/ve.c
index aff3b03..5f6896f 100644
--- a/kernel/ve/ve.c
+++ b/kernel/ve/ve.c
@@ -85,7 +85,6 @@ struct ve_struct ve0 = {
 };
 EXPORT_SYMBOL(ve0);
 
-LIST_HEAD(ve_list_head);
 DEFINE_MUTEX(ve_list_lock);
 
 int nr_ve = 1;	/* One VE always exists. Compatibility with vestat */
@@ -94,7 +93,7 @@ EXPORT_SYMBOL(nr_ve);
 int vz_compat;
 EXPORT_SYMBOL(vz_compat);
 
-static DEFINE_IDR(ve_idr);
+DEFINE_IDR(ve_idr);
 
 static int __init vz_compat_setup(char *arg)
 {
@@ -129,7 +128,6 @@ static int ve_list_add(struct ve_struct *ve)
 			err = -EEXIST;
 		goto out;
 	}
-	list_add(&ve->ve_list, &ve_list_head);
 	nr_ve++;
 	err = 0;
 out:
@@ -141,7 +139,6 @@ static void ve_list_del(struct ve_struct *ve)
 {
 	mutex_lock(&ve_list_lock);
 	idr_remove(&ve_idr, ve->veid);
-	list_del_init(&ve->ve_list);
 	nr_ve--;
 	mutex_unlock(&ve_list_lock);
 }
@@ -194,7 +191,7 @@ struct ve_struct *get_ve_by_id(envid_t veid)
 EXPORT_SYMBOL(get_ve_by_id);
 
 EXPORT_SYMBOL(ve_list_lock);
-EXPORT_SYMBOL(ve_list_head);
+EXPORT_SYMBOL(ve_idr);
 
 int vz_security_family_check(struct net *net, int family)
 {
@@ -627,7 +624,6 @@ static struct cgroup_subsys_state *ve_create(struct cgroup *cg)
 	init_rwsem(&ve->op_sem);
 	mutex_init(&ve->sync_mutex);
 	INIT_LIST_HEAD(&ve->devices);
-	INIT_LIST_HEAD(&ve->ve_list);
 	INIT_LIST_HEAD(&ve->devmnt_list);
 	mutex_init(&ve->devmnt_mutex);
 	kmapset_init_key(&ve->ve_sysfs_perms);
@@ -1201,7 +1197,7 @@ EXPORT_SYMBOL(ve_subsys);
 static int __init ve_subsys_init(void)
 {
 	ve_cachep = KMEM_CACHE(ve_struct, SLAB_PANIC);
-	list_add(&ve0.ve_list, &ve_list_head);
+	WARN_ON(idr_alloc(&ve_idr, &ve0, 0, 1, GFP_KERNEL) < 0);
 	return 0;
 }
 late_initcall(ve_subsys_init);
diff --git a/kernel/ve/vecalls.c b/kernel/ve/vecalls.c
index 9e86615..48c64d2 100644
--- a/kernel/ve/vecalls.c
+++ b/kernel/ve/vecalls.c
@@ -713,8 +713,7 @@ int real_ve_dev_map(envid_t veid, int op, char *dev_name)
 
 static int vestat_seq_show(struct seq_file *m, void *v)
 {
-	struct list_head *entry;
-	struct ve_struct *ve;
+	struct ve_struct *ve = v;
 	struct ve_struct *curve;
 	int ret;
 	unsigned long user_ve, nice_ve, system_ve;
@@ -722,11 +721,8 @@ static int vestat_seq_show(struct seq_file *m, void *v)
 	u64 uptime_cycles, idle_time, strv_time, used;
 	struct kernel_cpustat kstat;
 
-	entry = (struct list_head *)v;
-	ve = list_entry(entry, struct ve_struct, ve_list);
-
 	curve = get_exec_env();
-	if (entry == ve_list_head.next ||
+	if (ve == get_ve0() ||
 	    (!ve_is_super(curve) && ve == curve)) {
 		/* print header */
 		seq_printf(m, "%-*s\n",
@@ -772,26 +768,24 @@ static int vestat_seq_show(struct seq_file *m, void *v)
 
 void *ve_seq_start(struct seq_file *m, loff_t *pos)
 {
-	struct ve_struct *curve;
-
-	curve = get_exec_env();
 	mutex_lock(&ve_list_lock);
-	if (!ve_is_super(curve)) {
-		if (*pos != 0)
-			return NULL;
-		return &curve->ve_list;
-	}
 
-	return seq_list_start(&ve_list_head, *pos);
+	return ve_seq_next(m, NULL, pos);
 }
 EXPORT_SYMBOL(ve_seq_start);
 
 void *ve_seq_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	if (!ve_is_super(get_exec_env()))
-		return NULL;
-	else
-		return seq_list_next(v, &ve_list_head, pos);
+	struct ve_struct *ve = get_exec_env();
+	int id = *pos;
+
+	if (!ve_is_super(ve))
+		return *pos ? NULL : ve;
+
+	ve = idr_get_next(&ve_idr, &id);
+	*pos = id + 1;
+
+	return ve;
 }
 EXPORT_SYMBOL(ve_seq_next);
 
@@ -822,7 +816,7 @@ static struct file_operations proc_vestat_operations = {
 
 static int devperms_seq_show(struct seq_file *m, void *v)
 {
-	struct ve_struct *ve = list_entry(v, struct ve_struct, ve_list);
+	struct ve_struct *ve = v;
 
 	if (m->private == (void *)0) {
 		seq_printf(m, "Version: 2.7\n");
@@ -894,10 +888,8 @@ EXPORT_SYMBOL(vzmon_unregister_veaddr_print_cb);
 
 static int veinfo_seq_show(struct seq_file *m, void *v)
 {
-	struct ve_struct *ve;
 	ve_seq_print_t veaddr_seq_print;
-
-	ve = list_entry((struct list_head *)v, struct ve_struct, ve_list);
+	struct ve_struct *ve = v;
 
 	seq_printf(m, "%10s %5u %5u", ve_name(ve), ve->class_id, nr_threads_ve(ve));
 
diff --git a/kernel/ve/vzlist.c b/kernel/ve/vzlist.c
index 31362ea..39966eb 100644
--- a/kernel/ve/vzlist.c
+++ b/kernel/ve/vzlist.c
@@ -25,7 +25,7 @@ static DEFINE_SEMAPHORE(vzlist_sem);
 static int get_veids(struct vzlist_veidctl *s)
 {
 	int ret;
-	int ves;
+	int ves, id;
 	unsigned long size;
 	envid_t *buf;
 	struct ve_struct *ve;
@@ -44,7 +44,7 @@ static int get_veids(struct vzlist_veidctl *s)
 
 	ves = 0;
 	mutex_lock(&ve_list_lock);
-	for_each_ve(ve) {
+	idr_for_each_entry(&ve_idr, ve, id) {
 		if (size >= (ves + 1)*sizeof(envid_t))
 			buf[ves] = ve->veid;
 		ves++;
diff --git a/kernel/ve/vzstat.c b/kernel/ve/vzstat.c
index 650010d..1382763 100644
--- a/kernel/ve/vzstat.c
+++ b/kernel/ve/vzstat.c
@@ -302,12 +302,14 @@ static void mem_avg_show(struct seq_file *m, void *v)
 static void update_venum(void)
 {
 	struct ve_struct *ve;
+	int id;
 
 	mutex_lock(&ve_list_lock);
 	spin_lock_irq(&kstat_glb_lock);
-	for_each_ve(ve)
+	idr_for_each_entry(&ve_idr, ve, id) {
 		/* max_snap is already set in update_schedule_latency */
 		KSTAT_LAT_PCPU_UPDATE(&ve->sched_lat_ve);
+	}
 	spin_unlock_irq(&kstat_glb_lock);
 	mutex_unlock(&ve_list_lock);
 }



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