[PATCH tip/core/rcu 20/23] remove all rcu head initializations, except on_stack initializations
From: Paul E. McKenney
Date: Tue Apr 20 2010 - 17:46:13 EST
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Remove all rcu head inits. We don't care about the RCU head state before passing
it to call_rcu() anyway. Only leave the "on_stack" variants so debugobjects can
keep track of objects on stack.
This patch applies to current -tip based on 2.6.34-rc2.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
CC: David S. Miller <davem@xxxxxxxxxxxxx>
CC: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx>
CC: akpm@xxxxxxxxxxxxxxxxxxxx
CC: mingo@xxxxxxx
CC: laijs@xxxxxxxxxxxxxx
CC: dipankar@xxxxxxxxxx
CC: josh@xxxxxxxxxxxxxxxx
CC: dvhltc@xxxxxxxxxx
CC: niv@xxxxxxxxxx
CC: tglx@xxxxxxxxxxxxx
CC: peterz@xxxxxxxxxxxxx
CC: rostedt@xxxxxxxxxxx
CC: Valdis.Kletnieks@xxxxxx
CC: dhowells@xxxxxxxxxx
CC: eric.dumazet@xxxxxxxxx
CC: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/mm/pgtable.c | 1 -
block/cfq-iosched.c | 1 -
block/genhd.c | 1 -
drivers/staging/batman-adv/hard-interface.c | 1 -
fs/file.c | 3 --
fs/fs-writeback.c | 31 ++++++++++++++++++++++----
fs/partitions/check.c | 1 -
include/linux/init_task.h | 1 -
kernel/rcutiny.c | 6 +++++
kernel/rcutorture.c | 2 +
kernel/rcutree.c | 4 +++
mm/backing-dev.c | 1 -
mm/slob.c | 1 -
security/selinux/avc.c | 1 -
security/selinux/netnode.c | 2 -
15 files changed, 38 insertions(+), 19 deletions(-)
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index ebc2f38..2c7e801 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -92,7 +92,6 @@ static void pte_free_rcu_callback(struct rcu_head *head)
static void pte_free_submit(struct pte_freelist_batch *batch)
{
- INIT_RCU_HEAD(&batch->rcu);
call_rcu(&batch->rcu, pte_free_rcu_callback);
}
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 838834b..0b695dd 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -3741,7 +3741,6 @@ static void *cfq_init_queue(struct request_queue *q)
* second, in order to have larger depth for async operations.
*/
cfqd->last_delayed_sync = jiffies - HZ;
- INIT_RCU_HEAD(&cfqd->rcu);
return cfqd;
}
diff --git a/block/genhd.c b/block/genhd.c
index d13ba76..27e85a2 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -987,7 +987,6 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno)
if (!new_ptbl)
return -ENOMEM;
- INIT_RCU_HEAD(&new_ptbl->rcu_head);
new_ptbl->len = target;
for (i = 0; i < len; i++)
diff --git a/drivers/staging/batman-adv/hard-interface.c b/drivers/staging/batman-adv/hard-interface.c
index befd488..96ea0e5 100644
--- a/drivers/staging/batman-adv/hard-interface.c
+++ b/drivers/staging/batman-adv/hard-interface.c
@@ -301,7 +301,6 @@ int hardif_add_interface(char *dev, int if_num)
batman_if->if_num = if_num;
batman_if->dev = dev;
batman_if->if_active = IF_INACTIVE;
- INIT_RCU_HEAD(&batman_if->rcu);
printk(KERN_INFO "batman-adv:Adding interface: %s\n", dev);
avail_ifs++;
diff --git a/fs/file.c b/fs/file.c
index 34bb7f7..cccaead 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -178,7 +178,6 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
fdt->open_fds = (fd_set *)data;
data += nr / BITS_PER_BYTE;
fdt->close_on_exec = (fd_set *)data;
- INIT_RCU_HEAD(&fdt->rcu);
fdt->next = NULL;
return fdt;
@@ -312,7 +311,6 @@ struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
new_fdt->close_on_exec = (fd_set *)&newf->close_on_exec_init;
new_fdt->open_fds = (fd_set *)&newf->open_fds_init;
new_fdt->fd = &newf->fd_array[0];
- INIT_RCU_HEAD(&new_fdt->rcu);
new_fdt->next = NULL;
spin_lock(&oldf->file_lock);
@@ -430,7 +428,6 @@ struct files_struct init_files = {
.fd = &init_files.fd_array[0],
.close_on_exec = (fd_set *)&init_files.close_on_exec_init,
.open_fds = (fd_set *)&init_files.open_fds_init,
- .rcu = RCU_HEAD_INIT,
},
.file_lock = __SPIN_LOCK_UNLOCKED(init_task.file_lock),
};
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 4b37f7c..ea38c65 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -75,12 +75,33 @@ static inline bool bdi_work_on_stack(struct bdi_work *work)
return test_bit(WS_ONSTACK_B, &work->state);
}
-static inline void bdi_work_init(struct bdi_work *work,
- struct wb_writeback_args *args)
+static inline void __bdi_work_init(struct bdi_work *work,
+ struct wb_writeback_args *args,
+ int on_stack)
{
- INIT_RCU_HEAD(&work->rcu_head);
work->args = *args;
work->state = WS_USED;
+ if (on_stack) {
+ work->state |= WS_ONSTACK;
+ init_rcu_head_on_stack(&work->rcu_head);
+ }
+}
+
+static inline void bdi_work_init(struct bdi_work *work,
+ struct wb_writeback_args *args)
+{
+ __bdi_work_init(work, args, false);
+}
+
+static inline void bdi_work_init_on_stack(struct bdi_work *work,
+ struct wb_writeback_args *args)
+{
+ __bdi_work_init(work, args, true);
+}
+
+static inline void bdi_destroy_work_on_stack(struct bdi_work *work)
+{
+ destroy_rcu_head_on_stack(&work->rcu_head);
}
/**
@@ -233,11 +254,11 @@ static void bdi_sync_writeback(struct backing_dev_info *bdi,
};
struct bdi_work work;
- bdi_work_init(&work, &args);
- work.state |= WS_ONSTACK;
+ bdi_work_init_on_stack(&work, &args);
bdi_queue_work(bdi, &work);
bdi_wait_on_work_clear(&work);
+ bdi_destroy_work_on_stack(&work);
}
/**
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index e238ab2..7444e6f 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -456,7 +456,6 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
}
/* everything is up and running, commence */
- INIT_RCU_HEAD(&p->rcu_head);
rcu_assign_pointer(ptbl->part[partno], p);
/* suppress uevent if the disk supresses it */
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index b1ed1cd..7996fc2 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -49,7 +49,6 @@ extern struct group_info init_groups;
{ .first = &init_task.pids[PIDTYPE_PGID].node }, \
{ .first = &init_task.pids[PIDTYPE_SID].node }, \
}, \
- .rcu = RCU_HEAD_INIT, \
.level = 0, \
.numbers = { { \
.nr = 0, \
diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c
index b1804ff..38729d3 100644
--- a/kernel/rcutiny.c
+++ b/kernel/rcutiny.c
@@ -245,11 +245,13 @@ void rcu_barrier(void)
{
struct rcu_synchronize rcu;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(rcu_barrier);
@@ -257,11 +259,13 @@ void rcu_barrier_bh(void)
{
struct rcu_synchronize rcu;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu_bh(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(rcu_barrier_bh);
@@ -269,11 +273,13 @@ void rcu_barrier_sched(void)
{
struct rcu_synchronize rcu;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu_sched(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(rcu_barrier_sched);
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 58df55b..077defb 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -464,9 +464,11 @@ static void rcu_bh_torture_synchronize(void)
{
struct rcu_bh_torture_synchronize rcu;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb);
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
static struct rcu_torture_ops rcu_bh_ops = {
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index ba69969..d443734 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -1484,11 +1484,13 @@ void synchronize_sched(void)
if (rcu_blocking_is_gp())
return;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu_sched(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(synchronize_sched);
@@ -1508,11 +1510,13 @@ void synchronize_rcu_bh(void)
if (rcu_blocking_is_gp())
return;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu_bh(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index f13e067..1bba4ae 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -656,7 +656,6 @@ int bdi_init(struct backing_dev_info *bdi)
bdi->max_ratio = 100;
bdi->max_prop_frac = PROP_FRAC_BASE;
spin_lock_init(&bdi->wb_lock);
- INIT_RCU_HEAD(&bdi->rcu_head);
INIT_LIST_HEAD(&bdi->bdi_list);
INIT_LIST_HEAD(&bdi->wb_list);
INIT_LIST_HEAD(&bdi->work_list);
diff --git a/mm/slob.c b/mm/slob.c
index 837ebd6..6de238d 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -647,7 +647,6 @@ void kmem_cache_free(struct kmem_cache *c, void *b)
if (unlikely(c->flags & SLAB_DESTROY_BY_RCU)) {
struct slob_rcu *slob_rcu;
slob_rcu = b + (c->size - sizeof(struct slob_rcu));
- INIT_RCU_HEAD(&slob_rcu->head);
slob_rcu->size = c->size;
call_rcu(&slob_rcu->head, kmem_rcu_free);
} else {
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 989fef8..bf4e3bc 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -288,7 +288,6 @@ static struct avc_node *avc_alloc_node(void)
if (!node)
goto out;
- INIT_RCU_HEAD(&node->rhead);
INIT_HLIST_NODE(&node->list);
avc_cache_stats_incr(allocations);
diff --git a/security/selinux/netnode.c b/security/selinux/netnode.c
index dc92792..65ebfe9 100644
--- a/security/selinux/netnode.c
+++ b/security/selinux/netnode.c
@@ -183,8 +183,6 @@ static void sel_netnode_insert(struct sel_netnode *node)
BUG();
}
- INIT_RCU_HEAD(&node->rcu);
-
/* we need to impose a limit on the growth of the hash table so check
* this bucket to make sure it is within the specified bounds */
list_add_rcu(&node->list, &sel_netnode_hash[idx].list);
--
1.7.0
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