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Commit 1678b014 authored by Alessandro Rubini's avatar Alessandro Rubini
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buffers: use the irqsave version of spin locks 

Since the trigger often runs at interrupt time, we need the
irqsave/irqrestore spinlock in the critical sections of buffers.
Signed-off-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
Acked-by: 's avatarFederico Vaga <federico.vaga@gmail.com>
parent 035a5814
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Inline Side-by-side
Showing with 23 additions and 17 deletions
buffers/zio-buf-kmalloc.c
View file @ 1678b014
......@@ -67,16 +67,17 @@ static struct zio_block *zbk_alloc_block(struct zio_bi *bi,
struct zbk_instance *zbki = to_zbki(bi);
struct zbk_item *item;
struct zio_control *ctrl;
unsigned long flags;
void *data;
pr_debug("%s:%d\n", __func__, __LINE__);
/* alloc fails if we overflow the buffer size */
spin_lock(&bi->lock);
spin_lock_irqsave(&bi->lock, flags);
if (zbki->nitem >= bi->zattr_set.std_zattr[ZIO_ATTR_ZBUF_MAXLEN].value)
goto out_unlock;
zbki->nitem++;
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
/* alloc item and data. Control remains null at this point */
item = kmem_cache_alloc(zbk_slab, gfp);
......@@ -95,10 +96,10 @@ out_free:
kfree(data);
kmem_cache_free(zbk_slab, item);
zio_free_control(ctrl);
spin_lock(&bi->lock);
spin_lock_irqsave(&bi->lock, flags);
zbki->nitem--;
out_unlock:
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
return NULL;
}
......@@ -107,6 +108,7 @@ static void zbk_free_block(struct zio_bi *bi, struct zio_block *block)
{
struct zbk_item *item;
struct zbk_instance *zbki;
unsigned long flags;
int awake = 0;
pr_debug("%s:%d\n", __func__, __LINE__);
......@@ -114,12 +116,12 @@ static void zbk_free_block(struct zio_bi *bi, struct zio_block *block)
item = to_item(block);
zbki = item->instance;
spin_lock(&bi->lock);
spin_lock_irqsave(&bi->lock, flags);
if ( ((bi->flags & ZIO_DIR) == ZIO_DIR_OUTPUT) &&
zbki->nitem < bi->zattr_set.std_zattr[ZIO_ATTR_ZBUF_MAXLEN].value)
awake = 1;
zbki->nitem--;
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
kfree(block->data);
zio_free_control(zio_get_ctrl(block));
......@@ -144,7 +146,7 @@ static inline int __try_push(struct zio_bi *bi, struct zio_channel *chan,
* release the lock but also say we can't retrieve now.
*/
bi->flags |= ZIO_BI_PUSHING;
spin_unlock(&bi->lock);
spin_unlock(&bi->lock); /* Don't irqrestore here, keep them disabled */
pushed = (ti->t_op->push_block(ti, chan, block) == 0);
spin_lock(&bi->lock);
bi->flags &= ~ZIO_BI_PUSHING;
......@@ -157,13 +159,14 @@ static int zbk_store_block(struct zio_bi *bi, struct zio_block *block)
struct zbk_instance *zbki = to_zbki(bi);
struct zio_channel *chan = bi->chan;
struct zbk_item *item = to_item(block);
unsigned long flags;
int awake = 0, pushed = 0, isempty;
int output = (bi->flags & ZIO_DIR) == ZIO_DIR_OUTPUT;
pr_debug("%s:%d (%p, %p)\n", __func__, __LINE__, bi, block);
/* add to the buffer instance or push to the trigger */
spin_lock(&bi->lock);
spin_lock_irqsave(&bi->lock, flags);
isempty = list_empty(&zbki->list);
list_add_tail(&item->list, &zbki->list);
if (isempty) {
......@@ -174,7 +177,7 @@ static int zbk_store_block(struct zio_bi *bi, struct zio_block *block)
}
if (pushed)
list_del(&item->list);
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
/* if first input, awake user space */
if (awake)
......@@ -189,22 +192,23 @@ static struct zio_block *zbk_retr_block(struct zio_bi *bi)
struct zbk_instance *zbki;
struct zio_ti *ti;
struct list_head *first;
unsigned long flags;
zbki = to_zbki(bi);
spin_lock(&bi->lock);
spin_lock_irqsave(&bi->lock, flags);
if (list_empty(&zbki->list) || bi->flags & ZIO_BI_PUSHING)
goto out_unlock;
first = zbki->list.next;
item = list_entry(first, struct zbk_item, list);
list_del(&item->list);
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
pr_debug("%s:%d (%p, %p)\n", __func__, __LINE__, bi, item);
return &item->block;
out_unlock:
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
/* There is no data in buffer, and we may pull to have data soon */
ti = bi->cset->ti;
if ((bi->flags & ZIO_DIR) == ZIO_DIR_INPUT && ti->t_op->pull_block) {
......
buffers/zio-buf-vmalloc.c
View file @ 1678b014
......@@ -202,6 +202,7 @@ static int zbk_store_block(struct zio_bi *bi, struct zio_block *block)
struct zbk_instance *zbki = to_zbki(bi);
struct zio_channel *chan = bi->chan;
struct zbk_item *item;
unsigned long flags;
int awake = 0, pushed = 0, output, first;
pr_debug("%s:%d (%p, %p)\n", __func__, __LINE__, bi, block);
......@@ -212,7 +213,7 @@ static int zbk_store_block(struct zio_bi *bi, struct zio_block *block)
output = (bi->flags & ZIO_DIR) == ZIO_DIR_OUTPUT;
/* add to the buffer instance or push to the trigger */
spin_lock(&bi->lock);
spin_lock_irqsave(&bi->lock, flags);
first = list_empty(&zbki->list);
list_add_tail(&item->list, &zbki->list);
if (first) {
......@@ -225,7 +226,7 @@ static int zbk_store_block(struct zio_bi *bi, struct zio_block *block)
list_del(&item->list);
if (!first && zbki->flags & ZBK_FLAG_MERGE_DATA)
zbk_try_merge(zbki, item);
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
/* if first input, awake user space */
if (awake)
......@@ -240,18 +241,19 @@ static struct zio_block *zbk_retr_block(struct zio_bi *bi)
struct zbk_instance *zbki;
struct zio_ti *ti;
struct list_head *first;
unsigned long flags;
int awake = 0;
zbki = to_zbki(bi);
spin_lock(&bi->lock);
spin_lock_irqsave(&bi->lock, flags);
if (list_empty(&zbki->list) || bi->flags & ZIO_BI_PUSHING)
goto out_unlock;
first = zbki->list.next;
item = list_entry(first, struct zbk_item, list);
list_del(&item->list);
awake = 1;
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
if (awake && ((bi->flags & ZIO_DIR) == ZIO_DIR_OUTPUT))
wake_up_interruptible(&bi->q);
......@@ -259,7 +261,7 @@ static struct zio_block *zbk_retr_block(struct zio_bi *bi)
return &item->block;
out_unlock:
spin_unlock(&bi->lock);
spin_unlock_irqrestore(&bi->lock, flags);
/* There is no data in buffer, and we may pull to have data soon */
ti = bi->cset->ti;
if ((bi->flags & ZIO_DIR) == ZIO_DIR_INPUT && ti->t_op->pull_block) {
......
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