From 749d811f10a410b64cf4c674c498ec04316ec373 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <error27@gmail.com>
Date: Thu, 3 Jun 2010 20:19:28 +1000
Subject: padata: add parenthesis in MAX_SEQ_NR macro

MAX_SEQ_NR is used in padata_alloc_pd() like this:

        pd->max_seq_nr = (MAX_SEQ_NR / num_cpus) * num_cpus - 1;

It needs parenthesis or the divide by num_cpus takes precedence over the
subtraction.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index b1c9857f8402..ff8de1b71e4e 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -28,7 +28,7 @@
 #include <linux/slab.h>
 #include <linux/rcupdate.h>
 
-#define MAX_SEQ_NR INT_MAX - NR_CPUS
+#define MAX_SEQ_NR (INT_MAX - NR_CPUS)
 #define MAX_OBJ_NUM 1000
 
 static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
-- 
cgit 


From 4c879170296174bde05cd1c643dac16594edee77 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 7 Jul 2010 15:30:10 +0200
Subject: padata: Check for valid padata instance on start

This patch introduces the PADATA_INVALID flag which is
checked on padata start. This will be used to mark a padata
instance as invalid, if the padata cpumask does not intersect
with the active cpumask. we change padata_start to return an
error if the PADATA_INVALID is set. Also we adapt the only
padata user, pcrypt to this change.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index ff8de1b71e4e..e7d723a3e31d 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -485,6 +485,11 @@ static void padata_flush_queues(struct parallel_data *pd)
 	BUG_ON(atomic_read(&pd->refcnt) != 0);
 }
 
+static void __padata_start(struct padata_instance *pinst)
+{
+	pinst->flags |= PADATA_INIT;
+}
+
 /* Replace the internal control stucture with a new one. */
 static void padata_replace(struct padata_instance *pinst,
 			   struct parallel_data *pd_new)
@@ -619,11 +624,20 @@ EXPORT_SYMBOL(padata_remove_cpu);
  *
  * @pinst: padata instance to start
  */
-void padata_start(struct padata_instance *pinst)
+int padata_start(struct padata_instance *pinst)
 {
+	int err = 0;
+
 	mutex_lock(&pinst->lock);
-	pinst->flags |= PADATA_INIT;
+
+	if (pinst->flags & PADATA_INVALID)
+		err =-EINVAL;
+
+	 __padata_start(pinst);
+
 	mutex_unlock(&pinst->lock);
+
+	return err;
 }
 EXPORT_SYMBOL(padata_start);
 
-- 
cgit 


From ee836555120140f770005b8ce6673c913d1b9a98 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 7 Jul 2010 15:30:47 +0200
Subject: padata: Block until the instance is unused on stop

This patch makes padata_stop to block until the padata
instance is unused. Also we split padata_stop to a locked
and a unlocked version. This is in preparation to be able
to change the cpumask after a call to patata stop.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index e7d723a3e31d..9e18dfa372a9 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -490,6 +490,20 @@ static void __padata_start(struct padata_instance *pinst)
 	pinst->flags |= PADATA_INIT;
 }
 
+static void __padata_stop(struct padata_instance *pinst)
+{
+	if (!(pinst->flags & PADATA_INIT))
+		return;
+
+	pinst->flags &= ~PADATA_INIT;
+
+	synchronize_rcu();
+
+	get_online_cpus();
+	padata_flush_queues(pinst->pd);
+	put_online_cpus();
+}
+
 /* Replace the internal control stucture with a new one. */
 static void padata_replace(struct padata_instance *pinst,
 			   struct parallel_data *pd_new)
@@ -649,7 +663,7 @@ EXPORT_SYMBOL(padata_start);
 void padata_stop(struct padata_instance *pinst)
 {
 	mutex_lock(&pinst->lock);
-	pinst->flags &= ~PADATA_INIT;
+	__padata_stop(pinst);
 	mutex_unlock(&pinst->lock);
 }
 EXPORT_SYMBOL(padata_stop);
@@ -770,17 +784,11 @@ EXPORT_SYMBOL(padata_alloc);
  */
 void padata_free(struct padata_instance *pinst)
 {
-	padata_stop(pinst);
-
-	synchronize_rcu();
-
 #ifdef CONFIG_HOTPLUG_CPU
 	unregister_hotcpu_notifier(&pinst->cpu_notifier);
 #endif
-	get_online_cpus();
-	padata_flush_queues(pinst->pd);
-	put_online_cpus();
 
+	padata_stop(pinst);
 	padata_free_pd(pinst->pd);
 	free_cpumask_var(pinst->cpumask);
 	kfree(pinst);
-- 
cgit 


From 33e54450683c5e970ac007489d7921ba792d093c Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 7 Jul 2010 15:31:26 +0200
Subject: padata: Handle empty padata cpumasks

This patch fixes a bug when the padata cpumask does not
intersect with the active cpumask. In this case we get a
division by zero in padata_alloc_pd and we end up with a
useless padata instance. Padata can end up with an empty
cpumask for two reasons:

1. A user removed the last cpu that belongs to the padata
cpumask and the active cpumask.

2. The last cpu that belongs to the padata cpumask and the
active cpumask goes offline.

We introduce a function padata_validate_cpumask to check if the padata
cpumask does intersect with the active cpumask. If the cpumasks do not
intersect we mark the instance as invalid, so it can't be used. We do not
allocate the cpumask dependend recources in this case. This fixes the
division by zero and keeps the padate instance in a consistent state.

It's not possible to trigger this bug by now because the only padata user,
pcrypt uses always the possible cpumask.

Reported-by: Dan Kruchinin <dkruchinin@acm.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 50 insertions(+), 11 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 9e18dfa372a9..57ec4eb5f2e3 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -516,12 +516,27 @@ static void padata_replace(struct padata_instance *pinst,
 
 	synchronize_rcu();
 
-	padata_flush_queues(pd_old);
-	padata_free_pd(pd_old);
+	if (pd_old) {
+		padata_flush_queues(pd_old);
+		padata_free_pd(pd_old);
+	}
 
 	pinst->flags &= ~PADATA_RESET;
 }
 
+/* If cpumask contains no active cpu, we mark the instance as invalid. */
+static bool padata_validate_cpumask(struct padata_instance *pinst,
+				    const struct cpumask *cpumask)
+{
+	if (!cpumask_intersects(cpumask, cpu_active_mask)) {
+		pinst->flags |= PADATA_INVALID;
+		return false;
+	}
+
+	pinst->flags &= ~PADATA_INVALID;
+	return true;
+}
+
 /**
  * padata_set_cpumask - set the cpumask that padata should use
  *
@@ -531,11 +546,18 @@ static void padata_replace(struct padata_instance *pinst,
 int padata_set_cpumask(struct padata_instance *pinst,
 			cpumask_var_t cpumask)
 {
-	struct parallel_data *pd;
+	int valid;
 	int err = 0;
+	struct parallel_data *pd = NULL;
 
 	mutex_lock(&pinst->lock);
 
+	valid = padata_validate_cpumask(pinst, cpumask);
+	if (!valid) {
+		__padata_stop(pinst);
+		goto out_replace;
+	}
+
 	get_online_cpus();
 
 	pd = padata_alloc_pd(pinst, cpumask);
@@ -544,10 +566,14 @@ int padata_set_cpumask(struct padata_instance *pinst,
 		goto out;
 	}
 
+out_replace:
 	cpumask_copy(pinst->cpumask, cpumask);
 
 	padata_replace(pinst, pd);
 
+	if (valid)
+		__padata_start(pinst);
+
 out:
 	put_online_cpus();
 
@@ -567,6 +593,9 @@ static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
 			return -ENOMEM;
 
 		padata_replace(pinst, pd);
+
+		if (padata_validate_cpumask(pinst, pinst->cpumask))
+			__padata_start(pinst);
 	}
 
 	return 0;
@@ -597,9 +626,16 @@ EXPORT_SYMBOL(padata_add_cpu);
 
 static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
 {
-	struct parallel_data *pd;
+	struct parallel_data *pd = NULL;
 
 	if (cpumask_test_cpu(cpu, cpu_online_mask)) {
+
+		if (!padata_validate_cpumask(pinst, pinst->cpumask)) {
+			__padata_stop(pinst);
+			padata_replace(pinst, pd);
+			goto out;
+		}
+
 		pd = padata_alloc_pd(pinst, pinst->cpumask);
 		if (!pd)
 			return -ENOMEM;
@@ -607,6 +643,7 @@ static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
 		padata_replace(pinst, pd);
 	}
 
+out:
 	return 0;
 }
 
@@ -732,7 +769,7 @@ struct padata_instance *padata_alloc(const struct cpumask *cpumask,
 				     struct workqueue_struct *wq)
 {
 	struct padata_instance *pinst;
-	struct parallel_data *pd;
+	struct parallel_data *pd = NULL;
 
 	pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL);
 	if (!pinst)
@@ -740,12 +777,14 @@ struct padata_instance *padata_alloc(const struct cpumask *cpumask,
 
 	get_online_cpus();
 
-	pd = padata_alloc_pd(pinst, cpumask);
-	if (!pd)
+	if (!alloc_cpumask_var(&pinst->cpumask, GFP_KERNEL))
 		goto err_free_inst;
 
-	if (!alloc_cpumask_var(&pinst->cpumask, GFP_KERNEL))
-		goto err_free_pd;
+	if (padata_validate_cpumask(pinst, cpumask)) {
+		pd = padata_alloc_pd(pinst, cpumask);
+		if (!pd)
+			goto err_free_mask;
+	}
 
 	rcu_assign_pointer(pinst->pd, pd);
 
@@ -767,8 +806,8 @@ struct padata_instance *padata_alloc(const struct cpumask *cpumask,
 
 	return pinst;
 
-err_free_pd:
-	padata_free_pd(pd);
+err_free_mask:
+	free_cpumask_var(pinst->cpumask);
 err_free_inst:
 	kfree(pinst);
 	put_online_cpus();
-- 
cgit 


From 83f619f3c8abb82cac9158cf23c656ec5c184607 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 7 Jul 2010 15:32:02 +0200
Subject: padata: make padata_do_parallel to return zero on success

To return -EINPROGRESS on success in padata_do_parallel was
considered to be odd. This patch changes this to return zero
on success. Also the only user of padata, pcrypt is adapted to
convert a return of zero to -EINPROGRESS within the crypto layer.
This also removes the pcrypt fallback if padata_do_parallel
was called on a not running padata instance as we can't handle it
anymore. This fallback was unused, so it's save to remove it.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 57ec4eb5f2e3..ae8defcf0622 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -111,10 +111,13 @@ int padata_do_parallel(struct padata_instance *pinst,
 
 	pd = rcu_dereference(pinst->pd);
 
-	err = 0;
+	err = -EINVAL;
 	if (!(pinst->flags & PADATA_INIT))
 		goto out;
 
+	if (!cpumask_test_cpu(cb_cpu, pd->cpumask))
+		goto out;
+
 	err =  -EBUSY;
 	if ((pinst->flags & PADATA_RESET))
 		goto out;
@@ -122,11 +125,7 @@ int padata_do_parallel(struct padata_instance *pinst,
 	if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM)
 		goto out;
 
-	err = -EINVAL;
-	if (!cpumask_test_cpu(cb_cpu, pd->cpumask))
-		goto out;
-
-	err = -EINPROGRESS;
+	err = 0;
 	atomic_inc(&pd->refcnt);
 	padata->pd = pd;
 	padata->cb_cpu = cb_cpu;
-- 
cgit 


From 5f1a8c1bc724498ff32acbd59ed5263275676b9d Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 7 Jul 2010 15:32:39 +0200
Subject: padata: simplify serialization mechanism

We count the number of processed objects on a percpu basis,
so we need to go through all the percpu reorder queues to calculate
the sequence number of the next object that needs serialization.
This patch changes this to count the number of processed objects
global. So we can calculate the sequence number and the percpu
reorder queue of the next object that needs serialization without
searching through the percpu reorder queues. This avoids some
accesses to memory of foreign cpus.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 71 +++++++++++++++------------------------------------------
 1 file changed, 19 insertions(+), 52 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index ae8defcf0622..450d67d394b0 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -170,79 +170,47 @@ EXPORT_SYMBOL(padata_do_parallel);
  */
 static struct padata_priv *padata_get_next(struct parallel_data *pd)
 {
-	int cpu, num_cpus, empty, calc_seq_nr;
-	int seq_nr, next_nr, overrun, next_overrun;
+	int cpu, num_cpus;
+	int next_nr, next_index;
 	struct padata_queue *queue, *next_queue;
 	struct padata_priv *padata;
 	struct padata_list *reorder;
 
-	empty = 0;
-	next_nr = -1;
-	next_overrun = 0;
-	next_queue = NULL;
-
 	num_cpus = cpumask_weight(pd->cpumask);
 
-	for_each_cpu(cpu, pd->cpumask) {
-		queue = per_cpu_ptr(pd->queue, cpu);
-		reorder = &queue->reorder;
-
-		/*
-		 * Calculate the seq_nr of the object that should be
-		 * next in this reorder queue.
-		 */
-		overrun = 0;
-		calc_seq_nr = (atomic_read(&queue->num_obj) * num_cpus)
-			       + queue->cpu_index;
-
-		if (unlikely(calc_seq_nr > pd->max_seq_nr)) {
-			calc_seq_nr = calc_seq_nr - pd->max_seq_nr - 1;
-			overrun = 1;
-		}
-
-		if (!list_empty(&reorder->list)) {
-			padata = list_entry(reorder->list.next,
-					    struct padata_priv, list);
-
-			seq_nr  = padata->seq_nr;
-			BUG_ON(calc_seq_nr != seq_nr);
-		} else {
-			seq_nr = calc_seq_nr;
-			empty++;
-		}
-
-		if (next_nr < 0 || seq_nr < next_nr
-		    || (next_overrun && !overrun)) {
-			next_nr = seq_nr;
-			next_overrun = overrun;
-			next_queue = queue;
-		}
+	/*
+	 * Calculate the percpu reorder queue and the sequence
+	 * number of the next object.
+	 */
+	next_nr = pd->processed;
+	next_index = next_nr % num_cpus;
+	cpu = padata_index_to_cpu(pd, next_index);
+	next_queue = per_cpu_ptr(pd->queue, cpu);
+
+	if (unlikely(next_nr > pd->max_seq_nr)) {
+		next_nr = next_nr - pd->max_seq_nr - 1;
+		next_index = next_nr % num_cpus;
+		cpu = padata_index_to_cpu(pd, next_index);
+		next_queue = per_cpu_ptr(pd->queue, cpu);
+		pd->processed = 0;
 	}
 
 	padata = NULL;
 
-	if (empty == num_cpus)
-		goto out;
-
 	reorder = &next_queue->reorder;
 
 	if (!list_empty(&reorder->list)) {
 		padata = list_entry(reorder->list.next,
 				    struct padata_priv, list);
 
-		if (unlikely(next_overrun)) {
-			for_each_cpu(cpu, pd->cpumask) {
-				queue = per_cpu_ptr(pd->queue, cpu);
-				atomic_set(&queue->num_obj, 0);
-			}
-		}
+		BUG_ON(next_nr != padata->seq_nr);
 
 		spin_lock(&reorder->lock);
 		list_del_init(&padata->list);
 		atomic_dec(&pd->reorder_objects);
 		spin_unlock(&reorder->lock);
 
-		atomic_inc(&next_queue->num_obj);
+		pd->processed++;
 
 		goto out;
 	}
@@ -430,7 +398,6 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
 
 		INIT_WORK(&queue->pwork, padata_parallel_worker);
 		INIT_WORK(&queue->swork, padata_serial_worker);
-		atomic_set(&queue->num_obj, 0);
 	}
 
 	num_cpus = cpumask_weight(pd->cpumask);
-- 
cgit 


From e15bacbebb9dcc95f148f28dfc83a6d5e48b60b8 Mon Sep 17 00:00:00 2001
From: Dan Kruchinin <dkruchinin@acm.org>
Date: Wed, 14 Jul 2010 14:31:57 +0400
Subject: padata: Make two separate cpumasks

The aim of this patch is to make two separate cpumasks
for padata parallel and serial workers respectively.
It allows user to make more thin and sophisticated configurations
of padata framework. For example user may bind parallel and serial workers to non-intersecting
CPU groups to gain better performance. Also each padata instance has notifiers chain for its
cpumasks now. If either parallel or serial or both masks were changed all
interested subsystems will get notification about that. It's especially useful
if padata user uses algorithm for callback CPU selection according to serial cpumask.

Signed-off-by: Dan Kruchinin <dkruchinin@acm.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 471 +++++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 347 insertions(+), 124 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 450d67d394b0..84d0ca9dac9c 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -35,9 +35,9 @@ static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
 {
 	int cpu, target_cpu;
 
-	target_cpu = cpumask_first(pd->cpumask);
+	target_cpu = cpumask_first(pd->cpumask.pcpu);
 	for (cpu = 0; cpu < cpu_index; cpu++)
-		target_cpu = cpumask_next(target_cpu, pd->cpumask);
+		target_cpu = cpumask_next(target_cpu, pd->cpumask.pcpu);
 
 	return target_cpu;
 }
@@ -53,26 +53,27 @@ static int padata_cpu_hash(struct padata_priv *padata)
 	 * Hash the sequence numbers to the cpus by taking
 	 * seq_nr mod. number of cpus in use.
 	 */
-	cpu_index =  padata->seq_nr % cpumask_weight(pd->cpumask);
+	cpu_index =  padata->seq_nr % cpumask_weight(pd->cpumask.pcpu);
 
 	return padata_index_to_cpu(pd, cpu_index);
 }
 
-static void padata_parallel_worker(struct work_struct *work)
+static void padata_parallel_worker(struct work_struct *parallel_work)
 {
-	struct padata_queue *queue;
+	struct padata_parallel_queue *pqueue;
 	struct parallel_data *pd;
 	struct padata_instance *pinst;
 	LIST_HEAD(local_list);
 
 	local_bh_disable();
-	queue = container_of(work, struct padata_queue, pwork);
-	pd = queue->pd;
+	pqueue = container_of(parallel_work,
+			      struct padata_parallel_queue, work);
+	pd = pqueue->pd;
 	pinst = pd->pinst;
 
-	spin_lock(&queue->parallel.lock);
-	list_replace_init(&queue->parallel.list, &local_list);
-	spin_unlock(&queue->parallel.lock);
+	spin_lock(&pqueue->parallel.lock);
+	list_replace_init(&pqueue->parallel.list, &local_list);
+	spin_unlock(&pqueue->parallel.lock);
 
 	while (!list_empty(&local_list)) {
 		struct padata_priv *padata;
@@ -94,7 +95,7 @@ static void padata_parallel_worker(struct work_struct *work)
  * @pinst: padata instance
  * @padata: object to be parallelized
  * @cb_cpu: cpu the serialization callback function will run on,
- *          must be in the cpumask of padata.
+ *          must be in the serial cpumask of padata(i.e. cpumask.cbcpu).
  *
  * The parallelization callback function will run with BHs off.
  * Note: Every object which is parallelized by padata_do_parallel
@@ -104,7 +105,7 @@ int padata_do_parallel(struct padata_instance *pinst,
 		       struct padata_priv *padata, int cb_cpu)
 {
 	int target_cpu, err;
-	struct padata_queue *queue;
+	struct padata_parallel_queue *queue;
 	struct parallel_data *pd;
 
 	rcu_read_lock_bh();
@@ -115,7 +116,7 @@ int padata_do_parallel(struct padata_instance *pinst,
 	if (!(pinst->flags & PADATA_INIT))
 		goto out;
 
-	if (!cpumask_test_cpu(cb_cpu, pd->cpumask))
+	if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu))
 		goto out;
 
 	err =  -EBUSY;
@@ -136,13 +137,13 @@ int padata_do_parallel(struct padata_instance *pinst,
 	padata->seq_nr = atomic_inc_return(&pd->seq_nr);
 
 	target_cpu = padata_cpu_hash(padata);
-	queue = per_cpu_ptr(pd->queue, target_cpu);
+	queue = per_cpu_ptr(pd->pqueue, target_cpu);
 
 	spin_lock(&queue->parallel.lock);
 	list_add_tail(&padata->list, &queue->parallel.list);
 	spin_unlock(&queue->parallel.lock);
 
-	queue_work_on(target_cpu, pinst->wq, &queue->pwork);
+	queue_work_on(target_cpu, pinst->wq, &queue->work);
 
 out:
 	rcu_read_unlock_bh();
@@ -172,11 +173,11 @@ static struct padata_priv *padata_get_next(struct parallel_data *pd)
 {
 	int cpu, num_cpus;
 	int next_nr, next_index;
-	struct padata_queue *queue, *next_queue;
+	struct padata_parallel_queue *queue, *next_queue;
 	struct padata_priv *padata;
 	struct padata_list *reorder;
 
-	num_cpus = cpumask_weight(pd->cpumask);
+	num_cpus = cpumask_weight(pd->cpumask.pcpu);
 
 	/*
 	 * Calculate the percpu reorder queue and the sequence
@@ -185,13 +186,13 @@ static struct padata_priv *padata_get_next(struct parallel_data *pd)
 	next_nr = pd->processed;
 	next_index = next_nr % num_cpus;
 	cpu = padata_index_to_cpu(pd, next_index);
-	next_queue = per_cpu_ptr(pd->queue, cpu);
+	next_queue = per_cpu_ptr(pd->pqueue, cpu);
 
 	if (unlikely(next_nr > pd->max_seq_nr)) {
 		next_nr = next_nr - pd->max_seq_nr - 1;
 		next_index = next_nr % num_cpus;
 		cpu = padata_index_to_cpu(pd, next_index);
-		next_queue = per_cpu_ptr(pd->queue, cpu);
+		next_queue = per_cpu_ptr(pd->pqueue, cpu);
 		pd->processed = 0;
 	}
 
@@ -215,7 +216,7 @@ static struct padata_priv *padata_get_next(struct parallel_data *pd)
 		goto out;
 	}
 
-	queue = per_cpu_ptr(pd->queue, smp_processor_id());
+	queue = per_cpu_ptr(pd->pqueue, smp_processor_id());
 	if (queue->cpu_index == next_queue->cpu_index) {
 		padata = ERR_PTR(-ENODATA);
 		goto out;
@@ -229,7 +230,7 @@ out:
 static void padata_reorder(struct parallel_data *pd)
 {
 	struct padata_priv *padata;
-	struct padata_queue *queue;
+	struct padata_serial_queue *squeue;
 	struct padata_instance *pinst = pd->pinst;
 
 	/*
@@ -268,13 +269,13 @@ static void padata_reorder(struct parallel_data *pd)
 			return;
 		}
 
-		queue = per_cpu_ptr(pd->queue, padata->cb_cpu);
+		squeue = per_cpu_ptr(pd->squeue, padata->cb_cpu);
 
-		spin_lock(&queue->serial.lock);
-		list_add_tail(&padata->list, &queue->serial.list);
-		spin_unlock(&queue->serial.lock);
+		spin_lock(&squeue->serial.lock);
+		list_add_tail(&padata->list, &squeue->serial.list);
+		spin_unlock(&squeue->serial.lock);
 
-		queue_work_on(padata->cb_cpu, pinst->wq, &queue->swork);
+		queue_work_on(padata->cb_cpu, pinst->wq, &squeue->work);
 	}
 
 	spin_unlock_bh(&pd->lock);
@@ -300,19 +301,19 @@ static void padata_reorder_timer(unsigned long arg)
 	padata_reorder(pd);
 }
 
-static void padata_serial_worker(struct work_struct *work)
+static void padata_serial_worker(struct work_struct *serial_work)
 {
-	struct padata_queue *queue;
+	struct padata_serial_queue *squeue;
 	struct parallel_data *pd;
 	LIST_HEAD(local_list);
 
 	local_bh_disable();
-	queue = container_of(work, struct padata_queue, swork);
-	pd = queue->pd;
+	squeue = container_of(serial_work, struct padata_serial_queue, work);
+	pd = squeue->pd;
 
-	spin_lock(&queue->serial.lock);
-	list_replace_init(&queue->serial.list, &local_list);
-	spin_unlock(&queue->serial.lock);
+	spin_lock(&squeue->serial.lock);
+	list_replace_init(&squeue->serial.list, &local_list);
+	spin_unlock(&squeue->serial.lock);
 
 	while (!list_empty(&local_list)) {
 		struct padata_priv *padata;
@@ -339,18 +340,18 @@ static void padata_serial_worker(struct work_struct *work)
 void padata_do_serial(struct padata_priv *padata)
 {
 	int cpu;
-	struct padata_queue *queue;
+	struct padata_parallel_queue *pqueue;
 	struct parallel_data *pd;
 
 	pd = padata->pd;
 
 	cpu = get_cpu();
-	queue = per_cpu_ptr(pd->queue, cpu);
+	pqueue = per_cpu_ptr(pd->pqueue, cpu);
 
-	spin_lock(&queue->reorder.lock);
+	spin_lock(&pqueue->reorder.lock);
 	atomic_inc(&pd->reorder_objects);
-	list_add_tail(&padata->list, &queue->reorder.list);
-	spin_unlock(&queue->reorder.lock);
+	list_add_tail(&padata->list, &pqueue->reorder.list);
+	spin_unlock(&pqueue->reorder.lock);
 
 	put_cpu();
 
@@ -358,51 +359,88 @@ void padata_do_serial(struct padata_priv *padata)
 }
 EXPORT_SYMBOL(padata_do_serial);
 
-/* Allocate and initialize the internal cpumask dependend resources. */
-static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
-					     const struct cpumask *cpumask)
+static int padata_setup_cpumasks(struct parallel_data *pd,
+				 const struct cpumask *pcpumask,
+				 const struct cpumask *cbcpumask)
 {
-	int cpu, cpu_index, num_cpus;
-	struct padata_queue *queue;
-	struct parallel_data *pd;
+	if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL))
+		return -ENOMEM;
 
-	cpu_index = 0;
+	cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_active_mask);
+	if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) {
+		free_cpumask_var(pd->cpumask.cbcpu);
+		return -ENOMEM;
+	}
 
-	pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL);
-	if (!pd)
-		goto err;
+	cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_active_mask);
+	return 0;
+}
 
-	pd->queue = alloc_percpu(struct padata_queue);
-	if (!pd->queue)
-		goto err_free_pd;
+static void __padata_list_init(struct padata_list *pd_list)
+{
+	INIT_LIST_HEAD(&pd_list->list);
+	spin_lock_init(&pd_list->lock);
+}
 
-	if (!alloc_cpumask_var(&pd->cpumask, GFP_KERNEL))
-		goto err_free_queue;
+/* Initialize all percpu queues used by serial workers */
+static void padata_init_squeues(struct parallel_data *pd)
+{
+	int cpu;
+	struct padata_serial_queue *squeue;
 
-	cpumask_and(pd->cpumask, cpumask, cpu_active_mask);
+	for_each_cpu(cpu, pd->cpumask.cbcpu) {
+		squeue = per_cpu_ptr(pd->squeue, cpu);
+		squeue->pd = pd;
+		__padata_list_init(&squeue->serial);
+		INIT_WORK(&squeue->work, padata_serial_worker);
+	}
+}
 
-	for_each_cpu(cpu, pd->cpumask) {
-		queue = per_cpu_ptr(pd->queue, cpu);
+/* Initialize all percpu queues used by parallel workers */
+static void padata_init_pqueues(struct parallel_data *pd)
+{
+	int cpu_index, num_cpus, cpu;
+	struct padata_parallel_queue *pqueue;
 
-		queue->pd = pd;
+	cpu_index = 0;
+	for_each_cpu(cpu, pd->cpumask.pcpu) {
+		pqueue = per_cpu_ptr(pd->pqueue, cpu);
+		pqueue->pd = pd;
+		pqueue->cpu_index = cpu_index;
+
+		__padata_list_init(&pqueue->reorder);
+		__padata_list_init(&pqueue->parallel);
+		INIT_WORK(&pqueue->work, padata_parallel_worker);
+		atomic_set(&pqueue->num_obj, 0);
+	}
 
-		queue->cpu_index = cpu_index;
-		cpu_index++;
+	num_cpus = cpumask_weight(pd->cpumask.pcpu);
+	pd->max_seq_nr = (MAX_SEQ_NR / num_cpus) * num_cpus - 1;
+}
 
-		INIT_LIST_HEAD(&queue->reorder.list);
-		INIT_LIST_HEAD(&queue->parallel.list);
-		INIT_LIST_HEAD(&queue->serial.list);
-		spin_lock_init(&queue->reorder.lock);
-		spin_lock_init(&queue->parallel.lock);
-		spin_lock_init(&queue->serial.lock);
+/* Allocate and initialize the internal cpumask dependend resources. */
+static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
+					     const struct cpumask *pcpumask,
+					     const struct cpumask *cbcpumask)
+{
+	struct parallel_data *pd;
 
-		INIT_WORK(&queue->pwork, padata_parallel_worker);
-		INIT_WORK(&queue->swork, padata_serial_worker);
-	}
+	pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL);
+	if (!pd)
+		goto err;
 
-	num_cpus = cpumask_weight(pd->cpumask);
-	pd->max_seq_nr = (MAX_SEQ_NR / num_cpus) * num_cpus - 1;
+	pd->pqueue = alloc_percpu(struct padata_parallel_queue);
+	if (!pd->pqueue)
+		goto err_free_pd;
+
+	pd->squeue = alloc_percpu(struct padata_serial_queue);
+	if (!pd->squeue)
+		goto err_free_pqueue;
+	if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0)
+		goto err_free_squeue;
 
+	padata_init_pqueues(pd);
+	padata_init_squeues(pd);
 	setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
 	atomic_set(&pd->seq_nr, -1);
 	atomic_set(&pd->reorder_objects, 0);
@@ -412,8 +450,10 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
 
 	return pd;
 
-err_free_queue:
-	free_percpu(pd->queue);
+err_free_squeue:
+	free_percpu(pd->squeue);
+err_free_pqueue:
+	free_percpu(pd->pqueue);
 err_free_pd:
 	kfree(pd);
 err:
@@ -422,8 +462,10 @@ err:
 
 static void padata_free_pd(struct parallel_data *pd)
 {
-	free_cpumask_var(pd->cpumask);
-	free_percpu(pd->queue);
+	free_cpumask_var(pd->cpumask.pcpu);
+	free_cpumask_var(pd->cpumask.cbcpu);
+	free_percpu(pd->pqueue);
+	free_percpu(pd->squeue);
 	kfree(pd);
 }
 
@@ -431,11 +473,12 @@ static void padata_free_pd(struct parallel_data *pd)
 static void padata_flush_queues(struct parallel_data *pd)
 {
 	int cpu;
-	struct padata_queue *queue;
+	struct padata_parallel_queue *pqueue;
+	struct padata_serial_queue *squeue;
 
-	for_each_cpu(cpu, pd->cpumask) {
-		queue = per_cpu_ptr(pd->queue, cpu);
-		flush_work(&queue->pwork);
+	for_each_cpu(cpu, pd->cpumask.pcpu) {
+		pqueue = per_cpu_ptr(pd->pqueue, cpu);
+		flush_work(&pqueue->work);
 	}
 
 	del_timer_sync(&pd->timer);
@@ -443,9 +486,9 @@ static void padata_flush_queues(struct parallel_data *pd)
 	if (atomic_read(&pd->reorder_objects))
 		padata_reorder(pd);
 
-	for_each_cpu(cpu, pd->cpumask) {
-		queue = per_cpu_ptr(pd->queue, cpu);
-		flush_work(&queue->swork);
+	for_each_cpu(cpu, pd->cpumask.cbcpu) {
+		squeue = per_cpu_ptr(pd->squeue, cpu);
+		flush_work(&squeue->work);
 	}
 
 	BUG_ON(atomic_read(&pd->refcnt) != 0);
@@ -475,21 +518,63 @@ static void padata_replace(struct padata_instance *pinst,
 			   struct parallel_data *pd_new)
 {
 	struct parallel_data *pd_old = pinst->pd;
+	int notification_mask = 0;
 
 	pinst->flags |= PADATA_RESET;
 
 	rcu_assign_pointer(pinst->pd, pd_new);
 
 	synchronize_rcu();
+	if (!pd_old)
+		goto out;
 
-	if (pd_old) {
-		padata_flush_queues(pd_old);
-		padata_free_pd(pd_old);
-	}
+	padata_flush_queues(pd_old);
+	if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu))
+		notification_mask |= PADATA_CPU_PARALLEL;
+	if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu))
+		notification_mask |= PADATA_CPU_SERIAL;
+
+	padata_free_pd(pd_old);
+	if (notification_mask)
+		blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
+					     notification_mask, pinst);
 
+out:
 	pinst->flags &= ~PADATA_RESET;
 }
 
+/**
+ * padata_register_cpumask_notifier - Registers a notifier that will be called
+ *                             if either pcpu or cbcpu or both cpumasks change.
+ *
+ * @pinst: A poineter to padata instance
+ * @nblock: A pointer to notifier block.
+ */
+int padata_register_cpumask_notifier(struct padata_instance *pinst,
+				     struct notifier_block *nblock)
+{
+	return blocking_notifier_chain_register(&pinst->cpumask_change_notifier,
+						nblock);
+}
+EXPORT_SYMBOL(padata_register_cpumask_notifier);
+
+/**
+ * padata_unregister_cpumask_notifier - Unregisters cpumask notifier
+ *        registered earlier  using padata_register_cpumask_notifier
+ *
+ * @pinst: A pointer to data instance.
+ * @nlock: A pointer to notifier block.
+ */
+int padata_unregister_cpumask_notifier(struct padata_instance *pinst,
+				       struct notifier_block *nblock)
+{
+	return blocking_notifier_chain_unregister(
+		&pinst->cpumask_change_notifier,
+		nblock);
+}
+EXPORT_SYMBOL(padata_unregister_cpumask_notifier);
+
+
 /* If cpumask contains no active cpu, we mark the instance as invalid. */
 static bool padata_validate_cpumask(struct padata_instance *pinst,
 				    const struct cpumask *cpumask)
@@ -504,13 +589,82 @@ static bool padata_validate_cpumask(struct padata_instance *pinst,
 }
 
 /**
- * padata_set_cpumask - set the cpumask that padata should use
+ * padata_get_cpumask: Fetch serial or parallel cpumask from the
+ *                     given padata instance and copy it to @out_mask
+ *
+ * @pinst: A pointer to padata instance
+ * @cpumask_type: Specifies which cpumask will be copied.
+ *                Possible values are PADATA_CPU_SERIAL *or* PADATA_CPU_PARALLEL
+ *                corresponding to serial and parallel cpumask respectively.
+ * @out_mask: A pointer to cpumask structure where selected
+ *            cpumask will be copied.
+ */
+int padata_get_cpumask(struct padata_instance *pinst,
+		       int cpumask_type, struct cpumask *out_mask)
+{
+	struct parallel_data *pd;
+	int ret = 0;
+
+	rcu_read_lock_bh();
+	pd = rcu_dereference(pinst->pd);
+	switch (cpumask_type) {
+	case PADATA_CPU_SERIAL:
+		cpumask_copy(out_mask, pd->cpumask.cbcpu);
+		break;
+	case PADATA_CPU_PARALLEL:
+		cpumask_copy(out_mask, pd->cpumask.pcpu);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	rcu_read_unlock_bh();
+	return ret;
+}
+EXPORT_SYMBOL(padata_get_cpumask);
+
+/**
+ * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value
+ *                     equivalent to @cpumask.
  *
  * @pinst: padata instance
+ * @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding
+ *                to parallel and serial cpumasks respectively.
  * @cpumask: the cpumask to use
  */
-int padata_set_cpumask(struct padata_instance *pinst,
-			cpumask_var_t cpumask)
+int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
+		       cpumask_var_t cpumask)
+{
+	struct cpumask *serial_mask, *parallel_mask;
+
+	switch (cpumask_type) {
+	case PADATA_CPU_PARALLEL:
+		serial_mask = pinst->cpumask.cbcpu;
+		parallel_mask = cpumask;
+		break;
+	case PADATA_CPU_SERIAL:
+		parallel_mask = pinst->cpumask.pcpu;
+		serial_mask = cpumask;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return __padata_set_cpumasks(pinst, parallel_mask, serial_mask);
+}
+EXPORT_SYMBOL(padata_set_cpumask);
+
+/**
+ * __padata_set_cpumasks - Set both parallel and serial cpumasks. The first
+ *                         one is used by parallel workers and the second one
+ *                         by the wokers doing serialization.
+ *
+ * @pinst: padata instance
+ * @pcpumask: the cpumask to use for parallel workers
+ * @cbcpumask: the cpumsak to use for serial workers
+ */
+int __padata_set_cpumasks(struct padata_instance *pinst,
+			  cpumask_var_t pcpumask, cpumask_var_t cbcpumask)
 {
 	int valid;
 	int err = 0;
@@ -518,7 +672,13 @@ int padata_set_cpumask(struct padata_instance *pinst,
 
 	mutex_lock(&pinst->lock);
 
-	valid = padata_validate_cpumask(pinst, cpumask);
+	valid = padata_validate_cpumask(pinst, pcpumask);
+	if (!valid) {
+		__padata_stop(pinst);
+		goto out_replace;
+	}
+
+	valid = padata_validate_cpumask(pinst, cbcpumask);
 	if (!valid) {
 		__padata_stop(pinst);
 		goto out_replace;
@@ -526,14 +686,15 @@ int padata_set_cpumask(struct padata_instance *pinst,
 
 	get_online_cpus();
 
-	pd = padata_alloc_pd(pinst, cpumask);
+	pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
 	if (!pd) {
 		err = -ENOMEM;
 		goto out;
 	}
 
 out_replace:
-	cpumask_copy(pinst->cpumask, cpumask);
+	cpumask_copy(pinst->cpumask.pcpu, pcpumask);
+	cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
 
 	padata_replace(pinst, pd);
 
@@ -546,41 +707,57 @@ out:
 	mutex_unlock(&pinst->lock);
 
 	return err;
+
 }
-EXPORT_SYMBOL(padata_set_cpumask);
+EXPORT_SYMBOL(__padata_set_cpumasks);
 
 static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
 {
 	struct parallel_data *pd;
 
 	if (cpumask_test_cpu(cpu, cpu_active_mask)) {
-		pd = padata_alloc_pd(pinst, pinst->cpumask);
+		pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
+				     pinst->cpumask.cbcpu);
 		if (!pd)
 			return -ENOMEM;
 
 		padata_replace(pinst, pd);
 
-		if (padata_validate_cpumask(pinst, pinst->cpumask))
+		if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) &&
+		    padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
 			__padata_start(pinst);
 	}
 
 	return 0;
 }
 
-/**
- * padata_add_cpu - add a cpu to the padata cpumask
+ /**
+ * padata_add_cpu - add a cpu to one or both(parallel and serial)
+ *                  padata cpumasks.
  *
  * @pinst: padata instance
  * @cpu: cpu to add
+ * @mask: bitmask of flags specifying to which cpumask @cpu shuld be added.
+ *        The @mask may be any combination of the following flags:
+ *          PADATA_CPU_SERIAL   - serial cpumask
+ *          PADATA_CPU_PARALLEL - parallel cpumask
  */
-int padata_add_cpu(struct padata_instance *pinst, int cpu)
+
+int padata_add_cpu(struct padata_instance *pinst, int cpu, int mask)
 {
 	int err;
 
+	if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
+		return -EINVAL;
+
 	mutex_lock(&pinst->lock);
 
 	get_online_cpus();
-	cpumask_set_cpu(cpu, pinst->cpumask);
+	if (mask & PADATA_CPU_SERIAL)
+		cpumask_set_cpu(cpu, pinst->cpumask.cbcpu);
+	if (mask & PADATA_CPU_PARALLEL)
+		cpumask_set_cpu(cpu, pinst->cpumask.pcpu);
+
 	err = __padata_add_cpu(pinst, cpu);
 	put_online_cpus();
 
@@ -596,13 +773,15 @@ static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
 
 	if (cpumask_test_cpu(cpu, cpu_online_mask)) {
 
-		if (!padata_validate_cpumask(pinst, pinst->cpumask)) {
+		if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) ||
+		    !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) {
 			__padata_stop(pinst);
 			padata_replace(pinst, pd);
 			goto out;
 		}
 
-		pd = padata_alloc_pd(pinst, pinst->cpumask);
+		pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
+				     pinst->cpumask.cbcpu);
 		if (!pd)
 			return -ENOMEM;
 
@@ -613,20 +792,32 @@ out:
 	return 0;
 }
 
-/**
- * padata_remove_cpu - remove a cpu from the padata cpumask
+ /**
+ * padata_remove_cpu - remove a cpu from the one or both(serial and paralell)
+ *                     padata cpumasks.
  *
  * @pinst: padata instance
  * @cpu: cpu to remove
+ * @mask: bitmask specifying from which cpumask @cpu should be removed
+ *        The @mask may be any combination of the following flags:
+ *          PADATA_CPU_SERIAL   - serial cpumask
+ *          PADATA_CPU_PARALLEL - parallel cpumask
  */
-int padata_remove_cpu(struct padata_instance *pinst, int cpu)
+int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask)
 {
 	int err;
 
+	if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
+		return -EINVAL;
+
 	mutex_lock(&pinst->lock);
 
 	get_online_cpus();
-	cpumask_clear_cpu(cpu, pinst->cpumask);
+	if (mask & PADATA_CPU_SERIAL)
+		cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu);
+	if (mask & PADATA_CPU_PARALLEL)
+		cpumask_clear_cpu(cpu, pinst->cpumask.pcpu);
+
 	err = __padata_remove_cpu(pinst, cpu);
 	put_online_cpus();
 
@@ -672,6 +863,14 @@ void padata_stop(struct padata_instance *pinst)
 EXPORT_SYMBOL(padata_stop);
 
 #ifdef CONFIG_HOTPLUG_CPU
+
+static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu)
+{
+	return cpumask_test_cpu(cpu, pinst->cpumask.pcpu) ||
+		cpumask_test_cpu(cpu, pinst->cpumask.cbcpu);
+}
+
+
 static int padata_cpu_callback(struct notifier_block *nfb,
 			       unsigned long action, void *hcpu)
 {
@@ -684,7 +883,7 @@ static int padata_cpu_callback(struct notifier_block *nfb,
 	switch (action) {
 	case CPU_ONLINE:
 	case CPU_ONLINE_FROZEN:
-		if (!cpumask_test_cpu(cpu, pinst->cpumask))
+		if (!pinst_has_cpu(pinst, cpu))
 			break;
 		mutex_lock(&pinst->lock);
 		err = __padata_add_cpu(pinst, cpu);
@@ -695,7 +894,7 @@ static int padata_cpu_callback(struct notifier_block *nfb,
 
 	case CPU_DOWN_PREPARE:
 	case CPU_DOWN_PREPARE_FROZEN:
-		if (!cpumask_test_cpu(cpu, pinst->cpumask))
+		if (!pinst_has_cpu(pinst, cpu))
 			break;
 		mutex_lock(&pinst->lock);
 		err = __padata_remove_cpu(pinst, cpu);
@@ -706,7 +905,7 @@ static int padata_cpu_callback(struct notifier_block *nfb,
 
 	case CPU_UP_CANCELED:
 	case CPU_UP_CANCELED_FROZEN:
-		if (!cpumask_test_cpu(cpu, pinst->cpumask))
+		if (!pinst_has_cpu(pinst, cpu))
 			break;
 		mutex_lock(&pinst->lock);
 		__padata_remove_cpu(pinst, cpu);
@@ -714,7 +913,7 @@ static int padata_cpu_callback(struct notifier_block *nfb,
 
 	case CPU_DOWN_FAILED:
 	case CPU_DOWN_FAILED_FROZEN:
-		if (!cpumask_test_cpu(cpu, pinst->cpumask))
+		if (!pinst_has_cpu(pinst, cpu))
 			break;
 		mutex_lock(&pinst->lock);
 		__padata_add_cpu(pinst, cpu);
@@ -726,13 +925,29 @@ static int padata_cpu_callback(struct notifier_block *nfb,
 #endif
 
 /**
- * padata_alloc - allocate and initialize a padata instance
+ * padata_alloc - Allocate and initialize padata instance.
+ *                Use default cpumask(cpu_possible_mask)
+ *                for serial and parallel workes.
+ *
+ * @wq: workqueue to use for the allocated padata instance
+ */
+struct padata_instance *padata_alloc(struct workqueue_struct *wq)
+{
+	return __padata_alloc(wq, cpu_possible_mask, cpu_possible_mask);
+}
+EXPORT_SYMBOL(padata_alloc);
+
+/**
+ * __padata_alloc - allocate and initialize a padata instance
+ *                  and specify cpumasks for serial and parallel workers.
  *
- * @cpumask: cpumask that padata uses for parallelization
  * @wq: workqueue to use for the allocated padata instance
+ * @pcpumask: cpumask that will be used for padata parallelization
+ * @cbcpumask: cpumask that will be used for padata serialization
  */
-struct padata_instance *padata_alloc(const struct cpumask *cpumask,
-				     struct workqueue_struct *wq)
+struct padata_instance *__padata_alloc(struct workqueue_struct *wq,
+				       const struct cpumask *pcpumask,
+				       const struct cpumask *cbcpumask)
 {
 	struct padata_instance *pinst;
 	struct parallel_data *pd = NULL;
@@ -742,21 +957,26 @@ struct padata_instance *padata_alloc(const struct cpumask *cpumask,
 		goto err;
 
 	get_online_cpus();
-
-	if (!alloc_cpumask_var(&pinst->cpumask, GFP_KERNEL))
+	if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL))
+		goto err_free_inst;
+	if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) {
+		free_cpumask_var(pinst->cpumask.pcpu);
 		goto err_free_inst;
-
-	if (padata_validate_cpumask(pinst, cpumask)) {
-		pd = padata_alloc_pd(pinst, cpumask);
-		if (!pd)
-			goto err_free_mask;
 	}
+	if (!padata_validate_cpumask(pinst, pcpumask) ||
+	    !padata_validate_cpumask(pinst, cbcpumask))
+		goto err_free_masks;
+
+	pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
+	if (!pd)
+		goto err_free_masks;
 
 	rcu_assign_pointer(pinst->pd, pd);
 
 	pinst->wq = wq;
 
-	cpumask_copy(pinst->cpumask, cpumask);
+	cpumask_copy(pinst->cpumask.pcpu, pcpumask);
+	cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
 
 	pinst->flags = 0;
 
@@ -768,19 +988,21 @@ struct padata_instance *padata_alloc(const struct cpumask *cpumask,
 
 	put_online_cpus();
 
+	BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier);
 	mutex_init(&pinst->lock);
 
 	return pinst;
 
-err_free_mask:
-	free_cpumask_var(pinst->cpumask);
+err_free_masks:
+	free_cpumask_var(pinst->cpumask.pcpu);
+	free_cpumask_var(pinst->cpumask.cbcpu);
 err_free_inst:
 	kfree(pinst);
 	put_online_cpus();
 err:
 	return NULL;
 }
-EXPORT_SYMBOL(padata_alloc);
+EXPORT_SYMBOL(__padata_alloc);
 
 /**
  * padata_free - free a padata instance
@@ -795,7 +1017,8 @@ void padata_free(struct padata_instance *pinst)
 
 	padata_stop(pinst);
 	padata_free_pd(pinst->pd);
-	free_cpumask_var(pinst->cpumask);
+	free_cpumask_var(pinst->cpumask.pcpu);
+	free_cpumask_var(pinst->cpumask.cbcpu);
 	kfree(pinst);
 }
 EXPORT_SYMBOL(padata_free);
-- 
cgit 


From 5e017dc3f8bc9e4a28983666e6bc00114a2018bb Mon Sep 17 00:00:00 2001
From: Dan Kruchinin <dkruchinin@acm.org>
Date: Wed, 14 Jul 2010 14:33:08 +0400
Subject: padata: Added sysfs primitives to padata subsystem

Added sysfs primitives to padata subsystem. Now API user may
embedded kobject each padata instance contains into any sysfs
hierarchy. For now padata sysfs interface provides only
two objects:
    serial_cpumask   [RW] - cpumask for serial workers
    parallel_cpumask [RW] - cpumask for parallel workers

Signed-off-by: Dan Kruchinin <dkruchinin@acm.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 146 insertions(+), 9 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 84d0ca9dac9c..526f9ea2fcc8 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -26,6 +26,7 @@
 #include <linux/mutex.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
+#include <linux/sysfs.h>
 #include <linux/rcupdate.h>
 
 #define MAX_SEQ_NR (INT_MAX - NR_CPUS)
@@ -924,6 +925,149 @@ static int padata_cpu_callback(struct notifier_block *nfb,
 }
 #endif
 
+static void __padata_free(struct padata_instance *pinst)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+	unregister_hotcpu_notifier(&pinst->cpu_notifier);
+#endif
+
+	padata_stop(pinst);
+	padata_free_pd(pinst->pd);
+	free_cpumask_var(pinst->cpumask.pcpu);
+	free_cpumask_var(pinst->cpumask.cbcpu);
+	kfree(pinst);
+}
+
+#define kobj2pinst(_kobj)					\
+	container_of(_kobj, struct padata_instance, kobj)
+#define attr2pentry(_attr)					\
+	container_of(_attr, struct padata_sysfs_entry, attr)
+
+static void padata_sysfs_release(struct kobject *kobj)
+{
+	struct padata_instance *pinst = kobj2pinst(kobj);
+	__padata_free(pinst);
+}
+
+struct padata_sysfs_entry {
+	struct attribute attr;
+	ssize_t (*show)(struct padata_instance *, struct attribute *, char *);
+	ssize_t (*store)(struct padata_instance *, struct attribute *,
+			 const char *, size_t);
+};
+
+static ssize_t show_cpumask(struct padata_instance *pinst,
+			    struct attribute *attr,  char *buf)
+{
+	struct cpumask *cpumask;
+	ssize_t len;
+
+	mutex_lock(&pinst->lock);
+	if (!strcmp(attr->name, "serial_cpumask"))
+		cpumask = pinst->cpumask.cbcpu;
+	else
+		cpumask = pinst->cpumask.pcpu;
+
+	len = bitmap_scnprintf(buf, PAGE_SIZE, cpumask_bits(cpumask),
+			       nr_cpu_ids);
+	if (PAGE_SIZE - len < 2)
+		len = -EINVAL;
+	else
+		len += sprintf(buf + len, "\n");
+
+	mutex_unlock(&pinst->lock);
+	return len;
+}
+
+static ssize_t store_cpumask(struct padata_instance *pinst,
+			     struct attribute *attr,
+			     const char *buf, size_t count)
+{
+	cpumask_var_t new_cpumask;
+	ssize_t ret;
+	int mask_type;
+
+	if (!alloc_cpumask_var(&new_cpumask, GFP_KERNEL))
+		return -ENOMEM;
+
+	ret = bitmap_parse(buf, count, cpumask_bits(new_cpumask),
+			   nr_cpumask_bits);
+	if (ret < 0)
+		goto out;
+
+	mask_type = !strcmp(attr->name, "serial_cpumask") ?
+		PADATA_CPU_SERIAL : PADATA_CPU_PARALLEL;
+	ret = padata_set_cpumask(pinst, mask_type, new_cpumask);
+	if (!ret)
+		ret = count;
+
+out:
+	free_cpumask_var(new_cpumask);
+	return ret;
+}
+
+#define PADATA_ATTR_RW(_name, _show_name, _store_name)		\
+	static struct padata_sysfs_entry _name##_attr =		\
+		__ATTR(_name, 0644, _show_name, _store_name)
+#define PADATA_ATTR_RO(_name, _show_name)		\
+	static struct padata_sysfs_entry _name##_attr = \
+		__ATTR(_name, 0400, _show_name, NULL)
+
+PADATA_ATTR_RW(serial_cpumask, show_cpumask, store_cpumask);
+PADATA_ATTR_RW(parallel_cpumask, show_cpumask, store_cpumask);
+
+/*
+ * Padata sysfs provides the following objects:
+ * serial_cpumask   [RW] - cpumask for serial workers
+ * parallel_cpumask [RW] - cpumask for parallel workers
+ */
+static struct attribute *padata_default_attrs[] = {
+	&serial_cpumask_attr.attr,
+	&parallel_cpumask_attr.attr,
+	NULL,
+};
+
+static ssize_t padata_sysfs_show(struct kobject *kobj,
+				 struct attribute *attr, char *buf)
+{
+	struct padata_instance *pinst;
+	struct padata_sysfs_entry *pentry;
+	ssize_t ret = -EIO;
+
+	pinst = kobj2pinst(kobj);
+	pentry = attr2pentry(attr);
+	if (pentry->show)
+		ret = pentry->show(pinst, attr, buf);
+
+	return ret;
+}
+
+static ssize_t padata_sysfs_store(struct kobject *kobj, struct attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct padata_instance *pinst;
+	struct padata_sysfs_entry *pentry;
+	ssize_t ret = -EIO;
+
+	pinst = kobj2pinst(kobj);
+	pentry = attr2pentry(attr);
+	if (pentry->show)
+		ret = pentry->store(pinst, attr, buf, count);
+
+	return ret;
+}
+
+static const struct sysfs_ops padata_sysfs_ops = {
+	.show = padata_sysfs_show,
+	.store = padata_sysfs_store,
+};
+
+static struct kobj_type padata_attr_type = {
+	.sysfs_ops = &padata_sysfs_ops,
+	.default_attrs = padata_default_attrs,
+	.release = padata_sysfs_release,
+};
+
 /**
  * padata_alloc - Allocate and initialize padata instance.
  *                Use default cpumask(cpu_possible_mask)
@@ -989,6 +1133,7 @@ struct padata_instance *__padata_alloc(struct workqueue_struct *wq,
 	put_online_cpus();
 
 	BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier);
+	kobject_init(&pinst->kobj, &padata_attr_type);
 	mutex_init(&pinst->lock);
 
 	return pinst;
@@ -1011,14 +1156,6 @@ EXPORT_SYMBOL(__padata_alloc);
  */
 void padata_free(struct padata_instance *pinst)
 {
-#ifdef CONFIG_HOTPLUG_CPU
-	unregister_hotcpu_notifier(&pinst->cpu_notifier);
-#endif
-
-	padata_stop(pinst);
-	padata_free_pd(pinst->pd);
-	free_cpumask_var(pinst->cpumask.pcpu);
-	free_cpumask_var(pinst->cpumask.cbcpu);
-	kfree(pinst);
+	kobject_put(&pinst->kobj);
 }
 EXPORT_SYMBOL(padata_free);
-- 
cgit 


From fad3a906d324c02b3c25ef51f702384154089846 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 20 Jul 2010 08:48:34 +0200
Subject: padata: Fix cpu index counting

The counting of the cpu index got lost with a recent commit.
This patch restores it. This fixes a hang of the parallel worker
threads on cpu hotplug.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 1 +
 1 file changed, 1 insertion(+)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 526f9ea2fcc8..4287868bbe37 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -408,6 +408,7 @@ static void padata_init_pqueues(struct parallel_data *pd)
 		pqueue = per_cpu_ptr(pd->pqueue, cpu);
 		pqueue->pd = pd;
 		pqueue->cpu_index = cpu_index;
+		cpu_index++;
 
 		__padata_list_init(&pqueue->reorder);
 		__padata_list_init(&pqueue->parallel);
-- 
cgit 


From b89661dff525a46edb7ee8a4423b5212068c05c0 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 20 Jul 2010 08:49:20 +0200
Subject: padata: Allocate cpumask dependend recources in any case

The cpumask separation work assumes the cpumask dependend recources
present regardless of valid or invalid cpumasks. With this patch
we allocate the cpumask dependend recources in any case. This fixes
two NULL pointer dereference crashes in padata_replace and in
padata_get_cpumask.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 24 +++++++-----------------
 1 file changed, 7 insertions(+), 17 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 4287868bbe37..6a519454a5bd 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -417,7 +417,7 @@ static void padata_init_pqueues(struct parallel_data *pd)
 	}
 
 	num_cpus = cpumask_weight(pd->cpumask.pcpu);
-	pd->max_seq_nr = (MAX_SEQ_NR / num_cpus) * num_cpus - 1;
+	pd->max_seq_nr = num_cpus ? (MAX_SEQ_NR / num_cpus) * num_cpus - 1 : 0;
 }
 
 /* Allocate and initialize the internal cpumask dependend resources. */
@@ -527,21 +527,19 @@ static void padata_replace(struct padata_instance *pinst,
 	rcu_assign_pointer(pinst->pd, pd_new);
 
 	synchronize_rcu();
-	if (!pd_old)
-		goto out;
 
-	padata_flush_queues(pd_old);
 	if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu))
 		notification_mask |= PADATA_CPU_PARALLEL;
 	if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu))
 		notification_mask |= PADATA_CPU_SERIAL;
 
+	padata_flush_queues(pd_old);
 	padata_free_pd(pd_old);
+
 	if (notification_mask)
 		blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
 					     notification_mask, pinst);
 
-out:
 	pinst->flags &= ~PADATA_RESET;
 }
 
@@ -673,6 +671,7 @@ int __padata_set_cpumasks(struct padata_instance *pinst,
 	struct parallel_data *pd = NULL;
 
 	mutex_lock(&pinst->lock);
+	get_online_cpus();
 
 	valid = padata_validate_cpumask(pinst, pcpumask);
 	if (!valid) {
@@ -681,20 +680,16 @@ int __padata_set_cpumasks(struct padata_instance *pinst,
 	}
 
 	valid = padata_validate_cpumask(pinst, cbcpumask);
-	if (!valid) {
+	if (!valid)
 		__padata_stop(pinst);
-		goto out_replace;
-	}
-
-	get_online_cpus();
 
+out_replace:
 	pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
 	if (!pd) {
 		err = -ENOMEM;
 		goto out;
 	}
 
-out_replace:
 	cpumask_copy(pinst->cpumask.pcpu, pcpumask);
 	cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
 
@@ -705,7 +700,6 @@ out_replace:
 
 out:
 	put_online_cpus();
-
 	mutex_unlock(&pinst->lock);
 
 	return err;
@@ -776,11 +770,8 @@ static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
 	if (cpumask_test_cpu(cpu, cpu_online_mask)) {
 
 		if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) ||
-		    !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) {
+		    !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
 			__padata_stop(pinst);
-			padata_replace(pinst, pd);
-			goto out;
-		}
 
 		pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
 				     pinst->cpumask.cbcpu);
@@ -790,7 +781,6 @@ static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
 		padata_replace(pinst, pd);
 	}
 
-out:
 	return 0;
 }
 
-- 
cgit 


From 7424713b83587006da72da84d7922471e366faba Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 20 Jul 2010 08:51:25 +0200
Subject: padata: Check for valid cpumasks

Now that we allow to change the cpumasks from userspace, we have
to check for valid cpumasks in padata_do_parallel. This patch adds
the necessary check. This fixes a division by zero crash if the
parallel cpumask contains no active cpu.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 6a519454a5bd..7f895e2b4efb 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -114,7 +114,7 @@ int padata_do_parallel(struct padata_instance *pinst,
 	pd = rcu_dereference(pinst->pd);
 
 	err = -EINVAL;
-	if (!(pinst->flags & PADATA_INIT))
+	if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID)
 		goto out;
 
 	if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu))
-- 
cgit 


From e6cc11707661770ca2bd4db4b0256d28f48e7541 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 27 Jul 2010 07:14:28 +0200
Subject: padata: Rename padata_alloc functions

We rename padata_alloc to padata_alloc_possible because this
function allocates a padata_instance and uses the cpu_possible
mask for parallel and serial workers. Also we rename __padata_alloc
to padata_alloc to avoid to export underlined functions. Underlined
functions are considered to be private to padata. Users are updated
accordingly.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 7f895e2b4efb..12860bce6b78 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -1060,29 +1060,29 @@ static struct kobj_type padata_attr_type = {
 };
 
 /**
- * padata_alloc - Allocate and initialize padata instance.
- *                Use default cpumask(cpu_possible_mask)
- *                for serial and parallel workes.
+ * padata_alloc_possible - Allocate and initialize padata instance.
+ *                         Use the cpu_possible_mask for serial and
+ *                         parallel workers.
  *
  * @wq: workqueue to use for the allocated padata instance
  */
-struct padata_instance *padata_alloc(struct workqueue_struct *wq)
+struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq)
 {
-	return __padata_alloc(wq, cpu_possible_mask, cpu_possible_mask);
+	return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask);
 }
-EXPORT_SYMBOL(padata_alloc);
+EXPORT_SYMBOL(padata_alloc_possible);
 
 /**
- * __padata_alloc - allocate and initialize a padata instance
- *                  and specify cpumasks for serial and parallel workers.
+ * padata_alloc - allocate and initialize a padata instance and specify
+ *                cpumasks for serial and parallel workers.
  *
  * @wq: workqueue to use for the allocated padata instance
  * @pcpumask: cpumask that will be used for padata parallelization
  * @cbcpumask: cpumask that will be used for padata serialization
  */
-struct padata_instance *__padata_alloc(struct workqueue_struct *wq,
-				       const struct cpumask *pcpumask,
-				       const struct cpumask *cbcpumask)
+struct padata_instance *padata_alloc(struct workqueue_struct *wq,
+				     const struct cpumask *pcpumask,
+				     const struct cpumask *cbcpumask)
 {
 	struct padata_instance *pinst;
 	struct parallel_data *pd = NULL;
@@ -1138,7 +1138,7 @@ err_free_inst:
 err:
 	return NULL;
 }
-EXPORT_SYMBOL(__padata_alloc);
+EXPORT_SYMBOL(padata_alloc);
 
 /**
  * padata_free - free a padata instance
-- 
cgit 


From 65ff577e6b6e482ee9de3569e058edebdc02f069 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 27 Jul 2010 07:15:06 +0200
Subject: padata: Rearrange set_cpumask functions

padata_set_cpumask needs to be protected by a lock. We make
__padata_set_cpumasks unlocked and static. So this function
can be used by the exported and locked padata_set_cpumask and
padata_set_cpumasks functions.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 117 ++++++++++++++++++++++++++++++++------------------------
 1 file changed, 67 insertions(+), 50 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 12860bce6b78..4987203770bc 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -623,6 +623,66 @@ int padata_get_cpumask(struct padata_instance *pinst,
 }
 EXPORT_SYMBOL(padata_get_cpumask);
 
+static int __padata_set_cpumasks(struct padata_instance *pinst,
+				 cpumask_var_t pcpumask,
+				 cpumask_var_t cbcpumask)
+{
+	int valid;
+	struct parallel_data *pd;
+
+	valid = padata_validate_cpumask(pinst, pcpumask);
+	if (!valid) {
+		__padata_stop(pinst);
+		goto out_replace;
+	}
+
+	valid = padata_validate_cpumask(pinst, cbcpumask);
+	if (!valid)
+		__padata_stop(pinst);
+
+out_replace:
+	pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
+	if (!pd)
+		return -ENOMEM;
+
+	cpumask_copy(pinst->cpumask.pcpu, pcpumask);
+	cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
+
+	padata_replace(pinst, pd);
+
+	if (valid)
+		__padata_start(pinst);
+
+	return 0;
+}
+
+/**
+ * padata_set_cpumasks - Set both parallel and serial cpumasks. The first
+ *                       one is used by parallel workers and the second one
+ *                       by the wokers doing serialization.
+ *
+ * @pinst: padata instance
+ * @pcpumask: the cpumask to use for parallel workers
+ * @cbcpumask: the cpumsak to use for serial workers
+ */
+int padata_set_cpumasks(struct padata_instance *pinst, cpumask_var_t pcpumask,
+			cpumask_var_t cbcpumask)
+{
+	int err;
+
+	mutex_lock(&pinst->lock);
+	get_online_cpus();
+
+	err = __padata_set_cpumasks(pinst, pcpumask, cbcpumask);
+
+	put_online_cpus();
+	mutex_unlock(&pinst->lock);
+
+	return err;
+
+}
+EXPORT_SYMBOL(padata_set_cpumasks);
+
 /**
  * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value
  *                     equivalent to @cpumask.
@@ -636,6 +696,10 @@ int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
 		       cpumask_var_t cpumask)
 {
 	struct cpumask *serial_mask, *parallel_mask;
+	int err = -EINVAL;
+
+	mutex_lock(&pinst->lock);
+	get_online_cpus();
 
 	switch (cpumask_type) {
 	case PADATA_CPU_PARALLEL:
@@ -647,65 +711,18 @@ int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
 		serial_mask = cpumask;
 		break;
 	default:
-		return -EINVAL;
+		 goto out;
 	}
 
-	return __padata_set_cpumasks(pinst, parallel_mask, serial_mask);
-}
-EXPORT_SYMBOL(padata_set_cpumask);
-
-/**
- * __padata_set_cpumasks - Set both parallel and serial cpumasks. The first
- *                         one is used by parallel workers and the second one
- *                         by the wokers doing serialization.
- *
- * @pinst: padata instance
- * @pcpumask: the cpumask to use for parallel workers
- * @cbcpumask: the cpumsak to use for serial workers
- */
-int __padata_set_cpumasks(struct padata_instance *pinst,
-			  cpumask_var_t pcpumask, cpumask_var_t cbcpumask)
-{
-	int valid;
-	int err = 0;
-	struct parallel_data *pd = NULL;
-
-	mutex_lock(&pinst->lock);
-	get_online_cpus();
-
-	valid = padata_validate_cpumask(pinst, pcpumask);
-	if (!valid) {
-		__padata_stop(pinst);
-		goto out_replace;
-	}
-
-	valid = padata_validate_cpumask(pinst, cbcpumask);
-	if (!valid)
-		__padata_stop(pinst);
-
-out_replace:
-	pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
-	if (!pd) {
-		err = -ENOMEM;
-		goto out;
-	}
-
-	cpumask_copy(pinst->cpumask.pcpu, pcpumask);
-	cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
-
-	padata_replace(pinst, pd);
-
-	if (valid)
-		__padata_start(pinst);
+	err =  __padata_set_cpumasks(pinst, parallel_mask, serial_mask);
 
 out:
 	put_online_cpus();
 	mutex_unlock(&pinst->lock);
 
 	return err;
-
 }
-EXPORT_SYMBOL(__padata_set_cpumasks);
+EXPORT_SYMBOL(padata_set_cpumask);
 
 static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
 {
-- 
cgit 


From c635696c7c0fbc720698dbec34bb83e53df6a967 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 27 Jul 2010 07:15:50 +0200
Subject: padata: Pass the padata cpumasks to the cpumask_change_notifier chain

We pass a pointer to the new padata cpumasks to the cpumask_change_notifier
chain. So users can access the cpumasks without the need of an extra
padata_get_cpumask function.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 4987203770bc..1c8c1d1d301d 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -538,7 +538,8 @@ static void padata_replace(struct padata_instance *pinst,
 
 	if (notification_mask)
 		blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
-					     notification_mask, pinst);
+					     notification_mask,
+					     &pd_new->cpumask);
 
 	pinst->flags &= ~PADATA_RESET;
 }
-- 
cgit 


From 0500e9b3f11ce84fc6ee48a3e29909145e58ba48 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 27 Jul 2010 07:19:27 +0200
Subject: padata: Remove padata_get_cpumask

A function that copies the padata cpumasks to a user buffer
is a bit error prone. The cpumask can change any time so we
can't be sure to have the right cpumask when using this function.
A user who is interested in the padata cpumasks should register
to the padata cpumask notifier chain instead. Users of
padata_get_cpumask are already updated, so we can remove it.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 kernel/padata.c | 35 -----------------------------------
 1 file changed, 35 deletions(-)

(limited to 'kernel/padata.c')

diff --git a/kernel/padata.c b/kernel/padata.c
index 1c8c1d1d301d..fd4679266ede 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -589,41 +589,6 @@ static bool padata_validate_cpumask(struct padata_instance *pinst,
 	return true;
 }
 
-/**
- * padata_get_cpumask: Fetch serial or parallel cpumask from the
- *                     given padata instance and copy it to @out_mask
- *
- * @pinst: A pointer to padata instance
- * @cpumask_type: Specifies which cpumask will be copied.
- *                Possible values are PADATA_CPU_SERIAL *or* PADATA_CPU_PARALLEL
- *                corresponding to serial and parallel cpumask respectively.
- * @out_mask: A pointer to cpumask structure where selected
- *            cpumask will be copied.
- */
-int padata_get_cpumask(struct padata_instance *pinst,
-		       int cpumask_type, struct cpumask *out_mask)
-{
-	struct parallel_data *pd;
-	int ret = 0;
-
-	rcu_read_lock_bh();
-	pd = rcu_dereference(pinst->pd);
-	switch (cpumask_type) {
-	case PADATA_CPU_SERIAL:
-		cpumask_copy(out_mask, pd->cpumask.cbcpu);
-		break;
-	case PADATA_CPU_PARALLEL:
-		cpumask_copy(out_mask, pd->cpumask.pcpu);
-		break;
-	default:
-		ret = -EINVAL;
-	}
-
-	rcu_read_unlock_bh();
-	return ret;
-}
-EXPORT_SYMBOL(padata_get_cpumask);
-
 static int __padata_set_cpumasks(struct padata_instance *pinst,
 				 cpumask_var_t pcpumask,
 				 cpumask_var_t cbcpumask)
-- 
cgit