* [RFC PATCH] block: set bdi congested when no tag available
@ 2022-02-18 8:48 Huangzhaoyang
2022-02-21 9:21 ` Zhaoyang Huang
2022-03-09 7:40 ` Zhaoyang Huang
0 siblings, 2 replies; 5+ messages in thread
From: Huangzhaoyang @ 2022-02-18 8:48 UTC (permalink / raw)
To: Jens Axboe, Martin K. Petersen, Ming Lei, Hannes Reinecke,
Bart Van Assche, Zhaoyang Huang, linux-kernel
From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
In previous version, block layer will set bdi to be congested when
get_request fail, which may throttle direct_reclaim. Move them back
under current design.
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
---
block/blk-mq-tag.c | 18 +++++++++++++++++-
include/linux/sbitmap.h | 1 +
lib/sbitmap.c | 17 +++++++++++++++++
3 files changed, 35 insertions(+), 1 deletion(-)
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 995336a..abb0685 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -11,6 +11,7 @@
#include <linux/blk-mq.h>
#include <linux/delay.h>
+#include <linux/backing-dev.h>
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-sched.h"
@@ -126,8 +127,11 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
if (tag != BLK_MQ_NO_TAG)
goto found_tag;
- if (data->flags & BLK_MQ_REQ_NOWAIT)
+ if (data->flags & BLK_MQ_REQ_NOWAIT) {
+ set_bdi_congested(data->q->disk->bdi,BLK_RW_SYNC);
+ set_bdi_congested(data->q->disk->bdi,BLK_RW_ASYNC);
return BLK_MQ_NO_TAG;
+ }
ws = bt_wait_ptr(bt, data->hctx);
do {
@@ -193,9 +197,21 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
return tag + tag_offset;
}
+static bool blk_mq_has_free_tags(struct blk_mq_tags *tags)
+{
+ if (!tags)
+ return true;
+
+ return sbitmap_any_bit_set(&tags->bitmap_tags.sb);
+}
+
void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
unsigned int tag)
{
+ if (!blk_mq_has_free_tags(tags)) {
+ clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_SYNC);
+ clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_ASYNC);
+ }
if (!blk_mq_tag_is_reserved(tags, tag)) {
const int real_tag = tag - tags->nr_reserved_tags;
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index 4a6ff27..30a5553 100644
--- a/include/linux/sbitmap.h
+++ b/include/linux/sbitmap.h
@@ -210,6 +210,7 @@ static inline void sbitmap_free(struct sbitmap *sb)
* Return: true if any bit in the bitmap is set, false otherwise.
*/
bool sbitmap_any_bit_set(const struct sbitmap *sb);
+bool sbitmap_any_bit_clear(const struct sbitmap *sb);
#define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift)
#define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U))
diff --git a/lib/sbitmap.c b/lib/sbitmap.c
index 2709ab8..baa30d8 100644
--- a/lib/sbitmap.c
+++ b/lib/sbitmap.c
@@ -309,6 +309,23 @@ bool sbitmap_any_bit_set(const struct sbitmap *sb)
}
EXPORT_SYMBOL_GPL(sbitmap_any_bit_set);
+bool sbitmap_any_bit_clear(const struct sbitmap *sb)
+{
+ unsigned int i;
+
+ for (i = 0; i < sb->map_nr; i++) {
+ const struct sbitmap_word *word = &sb->map[i];
+ unsigned long mask = word->word & ~word->cleared;
+ unsigned long ret;
+
+ ret = find_first_zero_bit(&mask, word->depth);
+ if (ret < word->depth)
+ return true;
+ }
+ return false;
+}
+EXPORT_SYMBOL_GPL(sbitmap_any_bit_clear);
+
static unsigned int __sbitmap_weight(const struct sbitmap *sb, bool set)
{
unsigned int i, weight = 0;
--
1.9.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [RFC PATCH] block: set bdi congested when no tag available
2022-02-18 8:48 [RFC PATCH] block: set bdi congested when no tag available Huangzhaoyang
@ 2022-02-21 9:21 ` Zhaoyang Huang
2022-03-09 7:40 ` Zhaoyang Huang
1 sibling, 0 replies; 5+ messages in thread
From: Zhaoyang Huang @ 2022-02-21 9:21 UTC (permalink / raw)
To: Jens Axboe, Martin K. Petersen, Ming Lei, Hannes Reinecke,
Bart Van Assche, Zhaoyang Huang, LKML
On Fri, Feb 18, 2022 at 4:48 PM Huangzhaoyang <huangzhaoyang@gmail.com> wrote:
>
> From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
>
> In previous version, block layer will set bdi to be congested when
> get_request fail, which may throttle direct_reclaim. Move them back
> under current design.
>
> Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
> ---
> block/blk-mq-tag.c | 18 +++++++++++++++++-
> include/linux/sbitmap.h | 1 +
> lib/sbitmap.c | 17 +++++++++++++++++
> 3 files changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
> index 995336a..abb0685 100644
> --- a/block/blk-mq-tag.c
> +++ b/block/blk-mq-tag.c
> @@ -11,6 +11,7 @@
>
> #include <linux/blk-mq.h>
> #include <linux/delay.h>
> +#include <linux/backing-dev.h>
> #include "blk.h"
> #include "blk-mq.h"
> #include "blk-mq-sched.h"
> @@ -126,8 +127,11 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> if (tag != BLK_MQ_NO_TAG)
> goto found_tag;
>
> - if (data->flags & BLK_MQ_REQ_NOWAIT)
> + if (data->flags & BLK_MQ_REQ_NOWAIT) {
> + set_bdi_congested(data->q->disk->bdi,BLK_RW_SYNC);
> + set_bdi_congested(data->q->disk->bdi,BLK_RW_ASYNC);
> return BLK_MQ_NO_TAG;
> + }
>
> ws = bt_wait_ptr(bt, data->hctx);
> do {
> @@ -193,9 +197,21 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> return tag + tag_offset;
> }
>
> +static bool blk_mq_has_free_tags(struct blk_mq_tags *tags)
> +{
> + if (!tags)
> + return true;
> +
> + return sbitmap_any_bit_set(&tags->bitmap_tags.sb);
should be return sbitmap_any_bit_clear(&tags->bitmap_tags.sb)
> +}
> +
> void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
> unsigned int tag)
> {
> + if (!blk_mq_has_free_tags(tags)) {
> + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_SYNC);
> + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_ASYNC);
> + }
> if (!blk_mq_tag_is_reserved(tags, tag)) {
> const int real_tag = tag - tags->nr_reserved_tags;
>
> diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
> index 4a6ff27..30a5553 100644
> --- a/include/linux/sbitmap.h
> +++ b/include/linux/sbitmap.h
> @@ -210,6 +210,7 @@ static inline void sbitmap_free(struct sbitmap *sb)
> * Return: true if any bit in the bitmap is set, false otherwise.
> */
> bool sbitmap_any_bit_set(const struct sbitmap *sb);
> +bool sbitmap_any_bit_clear(const struct sbitmap *sb);
>
> #define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift)
> #define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U))
> diff --git a/lib/sbitmap.c b/lib/sbitmap.c
> index 2709ab8..baa30d8 100644
> --- a/lib/sbitmap.c
> +++ b/lib/sbitmap.c
> @@ -309,6 +309,23 @@ bool sbitmap_any_bit_set(const struct sbitmap *sb)
> }
> EXPORT_SYMBOL_GPL(sbitmap_any_bit_set);
>
> +bool sbitmap_any_bit_clear(const struct sbitmap *sb)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < sb->map_nr; i++) {
> + const struct sbitmap_word *word = &sb->map[i];
> + unsigned long mask = word->word & ~word->cleared;
> + unsigned long ret;
> +
> + ret = find_first_zero_bit(&mask, word->depth);
> + if (ret < word->depth)
> + return true;
> + }
> + return false;
> +}
> +EXPORT_SYMBOL_GPL(sbitmap_any_bit_clear);
> +
> static unsigned int __sbitmap_weight(const struct sbitmap *sb, bool set)
> {
> unsigned int i, weight = 0;
> --
> 1.9.1
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* [RFC PATCH] block: set bdi congested when no tag available
2022-02-18 8:48 [RFC PATCH] block: set bdi congested when no tag available Huangzhaoyang
2022-02-21 9:21 ` Zhaoyang Huang
@ 2022-03-09 7:40 ` Zhaoyang Huang
2022-03-09 11:50 ` Vlastimil Babka
1 sibling, 1 reply; 5+ messages in thread
From: Zhaoyang Huang @ 2022-03-09 7:40 UTC (permalink / raw)
To: Jens Axboe, Martin K. Petersen, Ming Lei, Hannes Reinecke,
Bart Van Assche, Zhaoyang Huang, LKML, Andrew Morton,
open list:MEMORY MANAGEMENT
From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
In previous version, block layer will set bdi to be congested when
get_request fail, which may throttle direct_reclaim. Move them back
under current blk-mq design.
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
---
block/blk-mq-tag.c | 18 +++++++++++++++++-
include/linux/sbitmap.h | 1 +
lib/sbitmap.c | 17 +++++++++++++++++
3 files changed, 35 insertions(+), 1 deletion(-)
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 995336a..bd1e520 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -11,6 +11,7 @@
#include <linux/blk-mq.h>
#include <linux/delay.h>
+#include <linux/backing-dev.h>
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-sched.h"
@@ -126,8 +127,11 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
if (tag != BLK_MQ_NO_TAG)
goto found_tag;
- if (data->flags & BLK_MQ_REQ_NOWAIT)
+ if (data->flags & BLK_MQ_REQ_NOWAIT) {
+ set_bdi_congested(data->q->disk->bdi,BLK_RW_SYNC);
+ set_bdi_congested(data->q->disk->bdi,BLK_RW_ASYNC);
return BLK_MQ_NO_TAG;
+ }
ws = bt_wait_ptr(bt, data->hctx);
do {
@@ -193,9 +197,21 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
return tag + tag_offset;
}
+static bool blk_mq_has_free_tags(struct blk_mq_tags *tags)
+{
+ if (!tags)
+ return true;
+
+ return sbitmap_any_bit_clear(&tags->bitmap_tags.sb);
+}
+
void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
unsigned int tag)
{
+ if (!blk_mq_has_free_tags(tags)) {
+ clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_SYNC);
+ clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_ASYNC);
+ }
if (!blk_mq_tag_is_reserved(tags, tag)) {
const int real_tag = tag - tags->nr_reserved_tags;
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index 4a6ff27..30a5553 100644
--- a/include/linux/sbitmap.h
+++ b/include/linux/sbitmap.h
@@ -210,6 +210,7 @@ static inline void sbitmap_free(struct sbitmap *sb)
* Return: true if any bit in the bitmap is set, false otherwise.
*/
bool sbitmap_any_bit_set(const struct sbitmap *sb);
+bool sbitmap_any_bit_clear(const struct sbitmap *sb);
#define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift)
#define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U))
diff --git a/lib/sbitmap.c b/lib/sbitmap.c
index 2709ab8..baa30d8 100644
--- a/lib/sbitmap.c
+++ b/lib/sbitmap.c
@@ -309,6 +309,23 @@ bool sbitmap_any_bit_set(const struct sbitmap *sb)
}
EXPORT_SYMBOL_GPL(sbitmap_any_bit_set);
+bool sbitmap_any_bit_clear(const struct sbitmap *sb)
+{
+ unsigned int i;
+
+ for (i = 0; i < sb->map_nr; i++) {
+ const struct sbitmap_word *word = &sb->map[i];
+ unsigned long mask = word->word & ~word->cleared;
+ unsigned long ret;
+
+ ret = find_first_zero_bit(&mask, word->depth);
+ if (ret < word->depth)
+ return true;
+ }
+ return false;
+}
+EXPORT_SYMBOL_GPL(sbitmap_any_bit_clear);
+
static unsigned int __sbitmap_weight(const struct sbitmap *sb, bool set)
{
unsigned int i, weight = 0;
--
1.9.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [RFC PATCH] block: set bdi congested when no tag available
2022-03-09 7:40 ` Zhaoyang Huang
@ 2022-03-09 11:50 ` Vlastimil Babka
2022-06-15 8:58 ` Zhaoyang Huang
0 siblings, 1 reply; 5+ messages in thread
From: Vlastimil Babka @ 2022-03-09 11:50 UTC (permalink / raw)
To: Zhaoyang Huang, Jens Axboe, Martin K. Petersen, Ming Lei,
Hannes Reinecke, Bart Van Assche, Zhaoyang Huang, LKML,
Andrew Morton, open list:MEMORY MANAGEMENT, Mel Gorman
On 3/9/22 08:40, Zhaoyang Huang wrote:
> From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
>
> In previous version, block layer will set bdi to be congested when
> get_request fail, which may throttle direct_reclaim. Move them back
> under current blk-mq design.
Hm I thought Mel removed the direct reclaim throttling based on bdi
congestion in his series [1]. Maybe block layers has other uses (I have no
idea), for tracking congestion, that should be mentioned instead?
[1]
https://lore.kernel.org/all/20211022144651.19914-1-mgorman@techsingularity.net/
>
> Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
> ---
> block/blk-mq-tag.c | 18 +++++++++++++++++-
> include/linux/sbitmap.h | 1 +
> lib/sbitmap.c | 17 +++++++++++++++++
> 3 files changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
> index 995336a..bd1e520 100644
> --- a/block/blk-mq-tag.c
> +++ b/block/blk-mq-tag.c
> @@ -11,6 +11,7 @@
>
> #include <linux/blk-mq.h>
> #include <linux/delay.h>
> +#include <linux/backing-dev.h>
> #include "blk.h"
> #include "blk-mq.h"
> #include "blk-mq-sched.h"
> @@ -126,8 +127,11 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> if (tag != BLK_MQ_NO_TAG)
> goto found_tag;
>
> - if (data->flags & BLK_MQ_REQ_NOWAIT)
> + if (data->flags & BLK_MQ_REQ_NOWAIT) {
> + set_bdi_congested(data->q->disk->bdi,BLK_RW_SYNC);
> + set_bdi_congested(data->q->disk->bdi,BLK_RW_ASYNC);
> return BLK_MQ_NO_TAG;
> + }
>
> ws = bt_wait_ptr(bt, data->hctx);
> do {
> @@ -193,9 +197,21 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> return tag + tag_offset;
> }
>
> +static bool blk_mq_has_free_tags(struct blk_mq_tags *tags)
> +{
> + if (!tags)
> + return true;
> +
> + return sbitmap_any_bit_clear(&tags->bitmap_tags.sb);
> +}
> +
> void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
> unsigned int tag)
> {
> + if (!blk_mq_has_free_tags(tags)) {
> + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_SYNC);
> + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_ASYNC);
> + }
> if (!blk_mq_tag_is_reserved(tags, tag)) {
> const int real_tag = tag - tags->nr_reserved_tags;
>
> diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
> index 4a6ff27..30a5553 100644
> --- a/include/linux/sbitmap.h
> +++ b/include/linux/sbitmap.h
> @@ -210,6 +210,7 @@ static inline void sbitmap_free(struct sbitmap *sb)
> * Return: true if any bit in the bitmap is set, false otherwise.
> */
> bool sbitmap_any_bit_set(const struct sbitmap *sb);
> +bool sbitmap_any_bit_clear(const struct sbitmap *sb);
>
> #define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift)
> #define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U))
> diff --git a/lib/sbitmap.c b/lib/sbitmap.c
> index 2709ab8..baa30d8 100644
> --- a/lib/sbitmap.c
> +++ b/lib/sbitmap.c
> @@ -309,6 +309,23 @@ bool sbitmap_any_bit_set(const struct sbitmap *sb)
> }
> EXPORT_SYMBOL_GPL(sbitmap_any_bit_set);
>
> +bool sbitmap_any_bit_clear(const struct sbitmap *sb)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < sb->map_nr; i++) {
> + const struct sbitmap_word *word = &sb->map[i];
> + unsigned long mask = word->word & ~word->cleared;
> + unsigned long ret;
> +
> + ret = find_first_zero_bit(&mask, word->depth);
> + if (ret < word->depth)
> + return true;
> + }
> + return false;
> +}
> +EXPORT_SYMBOL_GPL(sbitmap_any_bit_clear);
> +
> static unsigned int __sbitmap_weight(const struct sbitmap *sb, bool set)
> {
> unsigned int i, weight = 0;
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [RFC PATCH] block: set bdi congested when no tag available
2022-03-09 11:50 ` Vlastimil Babka
@ 2022-06-15 8:58 ` Zhaoyang Huang
0 siblings, 0 replies; 5+ messages in thread
From: Zhaoyang Huang @ 2022-06-15 8:58 UTC (permalink / raw)
To: Vlastimil Babka
Cc: Jens Axboe, Martin K. Petersen, Ming Lei, Hannes Reinecke,
Bart Van Assche, Zhaoyang Huang, LKML, Andrew Morton,
open list:MEMORY MANAGEMENT, Mel Gorman
On Wed, Mar 9, 2022 at 7:50 PM Vlastimil Babka <vbabka@suse.cz> wrote:
>
> On 3/9/22 08:40, Zhaoyang Huang wrote:
> > From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
> >
> > In previous version, block layer will set bdi to be congested when
> > get_request fail, which may throttle direct_reclaim. Move them back
> > under current blk-mq design.
>
> Hm I thought Mel removed the direct reclaim throttling based on bdi
> congestion in his series [1]. Maybe block layers has other uses (I have no
> idea), for tracking congestion, that should be mentioned instead?
>
> [1]
> https://lore.kernel.org/all/20211022144651.19914-1-mgorman@techsingularity.net/
>
As my understanding, the above patch change suspending on bdi
congested for a given interval to be woken up by finish of request or
bio. This patch is not against above one, which add one more scenario
for setting bdi as congested.
> >
> > Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
> > ---
> > block/blk-mq-tag.c | 18 +++++++++++++++++-
> > include/linux/sbitmap.h | 1 +
> > lib/sbitmap.c | 17 +++++++++++++++++
> > 3 files changed, 35 insertions(+), 1 deletion(-)
> >
> > diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
> > index 995336a..bd1e520 100644
> > --- a/block/blk-mq-tag.c
> > +++ b/block/blk-mq-tag.c
> > @@ -11,6 +11,7 @@
> >
> > #include <linux/blk-mq.h>
> > #include <linux/delay.h>
> > +#include <linux/backing-dev.h>
> > #include "blk.h"
> > #include "blk-mq.h"
> > #include "blk-mq-sched.h"
> > @@ -126,8 +127,11 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> > if (tag != BLK_MQ_NO_TAG)
> > goto found_tag;
> >
> > - if (data->flags & BLK_MQ_REQ_NOWAIT)
> > + if (data->flags & BLK_MQ_REQ_NOWAIT) {
> > + set_bdi_congested(data->q->disk->bdi,BLK_RW_SYNC);
> > + set_bdi_congested(data->q->disk->bdi,BLK_RW_ASYNC);
> > return BLK_MQ_NO_TAG;
> > + }
> >
> > ws = bt_wait_ptr(bt, data->hctx);
> > do {
> > @@ -193,9 +197,21 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> > return tag + tag_offset;
> > }
> >
> > +static bool blk_mq_has_free_tags(struct blk_mq_tags *tags)
> > +{
> > + if (!tags)
> > + return true;
> > +
> > + return sbitmap_any_bit_clear(&tags->bitmap_tags.sb);
> > +}
> > +
> > void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
> > unsigned int tag)
> > {
> > + if (!blk_mq_has_free_tags(tags)) {
> > + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_SYNC);
> > + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_ASYNC);
> > + }
> > if (!blk_mq_tag_is_reserved(tags, tag)) {
> > const int real_tag = tag - tags->nr_reserved_tags;
> >
> > diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
> > index 4a6ff27..30a5553 100644
> > --- a/include/linux/sbitmap.h
> > +++ b/include/linux/sbitmap.h
> > @@ -210,6 +210,7 @@ static inline void sbitmap_free(struct sbitmap *sb)
> > * Return: true if any bit in the bitmap is set, false otherwise.
> > */
> > bool sbitmap_any_bit_set(const struct sbitmap *sb);
> > +bool sbitmap_any_bit_clear(const struct sbitmap *sb);
> >
> > #define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift)
> > #define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U))
> > diff --git a/lib/sbitmap.c b/lib/sbitmap.c
> > index 2709ab8..baa30d8 100644
> > --- a/lib/sbitmap.c
> > +++ b/lib/sbitmap.c
> > @@ -309,6 +309,23 @@ bool sbitmap_any_bit_set(const struct sbitmap *sb)
> > }
> > EXPORT_SYMBOL_GPL(sbitmap_any_bit_set);
> >
> > +bool sbitmap_any_bit_clear(const struct sbitmap *sb)
> > +{
> > + unsigned int i;
> > +
> > + for (i = 0; i < sb->map_nr; i++) {
> > + const struct sbitmap_word *word = &sb->map[i];
> > + unsigned long mask = word->word & ~word->cleared;
> > + unsigned long ret;
> > +
> > + ret = find_first_zero_bit(&mask, word->depth);
> > + if (ret < word->depth)
> > + return true;
> > + }
> > + return false;
> > +}
> > +EXPORT_SYMBOL_GPL(sbitmap_any_bit_clear);
> > +
> > static unsigned int __sbitmap_weight(const struct sbitmap *sb, bool set)
> > {
> > unsigned int i, weight = 0;
>
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-06-15 8:59 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-02-18 8:48 [RFC PATCH] block: set bdi congested when no tag available Huangzhaoyang
2022-02-21 9:21 ` Zhaoyang Huang
2022-03-09 7:40 ` Zhaoyang Huang
2022-03-09 11:50 ` Vlastimil Babka
2022-06-15 8:58 ` Zhaoyang Huang
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