[PATCH 5/5] blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTAT
From: Tejun Heo
Date: Wed Nov 06 2019 - 16:58:59 EST
blkg_rwstat is now only used by bfq-iosched and blk-throtl when on
cgroup1. Let's move it into its own files and gate it behind a config
option.
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
block/Kconfig | 4 +
block/Kconfig.iosched | 1 +
block/Makefile | 1 +
block/bfq-iosched.h | 2 +
block/blk-cgroup-rwstat.c | 129 ++++++++++++++++++++++++++++++
block/blk-cgroup-rwstat.h | 149 ++++++++++++++++++++++++++++++++++
block/blk-cgroup.c | 97 ----------------------
block/blk-throttle.c | 1 +
include/linux/blk-cgroup.h | 159 -------------------------------------
9 files changed, 287 insertions(+), 256 deletions(-)
create mode 100644 block/blk-cgroup-rwstat.c
create mode 100644 block/blk-cgroup-rwstat.h
diff --git a/block/Kconfig b/block/Kconfig
index 41c0917ce622..c23094a14a2b 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -32,6 +32,9 @@ config BLK_RQ_ALLOC_TIME
config BLK_SCSI_REQUEST
bool
+config BLK_CGROUP_RWSTAT
+ bool
+
config BLK_DEV_BSG
bool "Block layer SG support v4"
default y
@@ -86,6 +89,7 @@ config BLK_DEV_ZONED
config BLK_DEV_THROTTLING
bool "Block layer bio throttling support"
depends on BLK_CGROUP=y
+ select BLK_CGROUP_RWSTAT
---help---
Block layer bio throttling support. It can be used to limit
the IO rate to a device. IO rate policies are per cgroup and
diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched
index b89310a022ad..7df14133adc8 100644
--- a/block/Kconfig.iosched
+++ b/block/Kconfig.iosched
@@ -31,6 +31,7 @@ config IOSCHED_BFQ
config BFQ_GROUP_IOSCHED
bool "BFQ hierarchical scheduling support"
depends on IOSCHED_BFQ && BLK_CGROUP
+ select BLK_CGROUP_RWSTAT
---help---
Enable hierarchical scheduling in BFQ, using the blkio
diff --git a/block/Makefile b/block/Makefile
index 9ef57ace90d4..205a5f2fef17 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_BLK_SCSI_REQUEST) += scsi_ioctl.o
obj-$(CONFIG_BLK_DEV_BSG) += bsg.o
obj-$(CONFIG_BLK_DEV_BSGLIB) += bsg-lib.o
obj-$(CONFIG_BLK_CGROUP) += blk-cgroup.o
+obj-$(CONFIG_BLK_CGROUP_RWSTAT) += blk-cgroup-rwstat.o
obj-$(CONFIG_BLK_DEV_THROTTLING) += blk-throttle.o
obj-$(CONFIG_BLK_CGROUP_IOLATENCY) += blk-iolatency.o
obj-$(CONFIG_BLK_CGROUP_IOCOST) += blk-iocost.o
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index 2676c06218f1..9c82c1f35716 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -10,6 +10,8 @@
#include <linux/hrtimer.h>
#include <linux/blk-cgroup.h>
+#include "blk-cgroup-rwstat.h"
+
#define BFQ_IOPRIO_CLASSES 3
#define BFQ_CL_IDLE_TIMEOUT (HZ/5)
diff --git a/block/blk-cgroup-rwstat.c b/block/blk-cgroup-rwstat.c
new file mode 100644
index 000000000000..85d5790ac49b
--- /dev/null
+++ b/block/blk-cgroup-rwstat.c
@@ -0,0 +1,129 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Legacy blkg rwstat helpers enabled by CONFIG_BLK_CGROUP_RWSTAT.
+ * Do not use in new code.
+ */
+#include "blk-cgroup-rwstat.h"
+
+int blkg_rwstat_init(struct blkg_rwstat *rwstat, gfp_t gfp)
+{
+ int i, ret;
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++) {
+ ret = percpu_counter_init(&rwstat->cpu_cnt[i], 0, gfp);
+ if (ret) {
+ while (--i >= 0)
+ percpu_counter_destroy(&rwstat->cpu_cnt[i]);
+ return ret;
+ }
+ atomic64_set(&rwstat->aux_cnt[i], 0);
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(blkg_rwstat_init);
+
+void blkg_rwstat_exit(struct blkg_rwstat *rwstat)
+{
+ int i;
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++)
+ percpu_counter_destroy(&rwstat->cpu_cnt[i]);
+}
+EXPORT_SYMBOL_GPL(blkg_rwstat_exit);
+
+/**
+ * __blkg_prfill_rwstat - prfill helper for a blkg_rwstat
+ * @sf: seq_file to print to
+ * @pd: policy private data of interest
+ * @rwstat: rwstat to print
+ *
+ * Print @rwstat to @sf for the device assocaited with @pd.
+ */
+u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
+ const struct blkg_rwstat_sample *rwstat)
+{
+ static const char *rwstr[] = {
+ [BLKG_RWSTAT_READ] = "Read",
+ [BLKG_RWSTAT_WRITE] = "Write",
+ [BLKG_RWSTAT_SYNC] = "Sync",
+ [BLKG_RWSTAT_ASYNC] = "Async",
+ [BLKG_RWSTAT_DISCARD] = "Discard",
+ };
+ const char *dname = blkg_dev_name(pd->blkg);
+ u64 v;
+ int i;
+
+ if (!dname)
+ return 0;
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++)
+ seq_printf(sf, "%s %s %llu\n", dname, rwstr[i],
+ rwstat->cnt[i]);
+
+ v = rwstat->cnt[BLKG_RWSTAT_READ] +
+ rwstat->cnt[BLKG_RWSTAT_WRITE] +
+ rwstat->cnt[BLKG_RWSTAT_DISCARD];
+ seq_printf(sf, "%s Total %llu\n", dname, v);
+ return v;
+}
+EXPORT_SYMBOL_GPL(__blkg_prfill_rwstat);
+
+/**
+ * blkg_prfill_rwstat - prfill callback for blkg_rwstat
+ * @sf: seq_file to print to
+ * @pd: policy private data of interest
+ * @off: offset to the blkg_rwstat in @pd
+ *
+ * prfill callback for printing a blkg_rwstat.
+ */
+u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
+ int off)
+{
+ struct blkg_rwstat_sample rwstat = { };
+
+ blkg_rwstat_read((void *)pd + off, &rwstat);
+ return __blkg_prfill_rwstat(sf, pd, &rwstat);
+}
+EXPORT_SYMBOL_GPL(blkg_prfill_rwstat);
+
+/**
+ * blkg_rwstat_recursive_sum - collect hierarchical blkg_rwstat
+ * @blkg: blkg of interest
+ * @pol: blkcg_policy which contains the blkg_rwstat
+ * @off: offset to the blkg_rwstat in blkg_policy_data or @blkg
+ * @sum: blkg_rwstat_sample structure containing the results
+ *
+ * Collect the blkg_rwstat specified by @blkg, @pol and @off and all its
+ * online descendants and their aux counts. The caller must be holding the
+ * queue lock for online tests.
+ *
+ * If @pol is NULL, blkg_rwstat is at @off bytes into @blkg; otherwise, it
+ * is at @off bytes into @blkg's blkg_policy_data of the policy.
+ */
+void blkg_rwstat_recursive_sum(struct blkcg_gq *blkg, struct blkcg_policy *pol,
+ int off, struct blkg_rwstat_sample *sum)
+{
+ struct blkcg_gq *pos_blkg;
+ struct cgroup_subsys_state *pos_css;
+ unsigned int i;
+
+ lockdep_assert_held(&blkg->q->queue_lock);
+
+ rcu_read_lock();
+ blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) {
+ struct blkg_rwstat *rwstat;
+
+ if (!pos_blkg->online)
+ continue;
+
+ if (pol)
+ rwstat = (void *)blkg_to_pd(pos_blkg, pol) + off;
+ else
+ rwstat = (void *)pos_blkg + off;
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++)
+ sum->cnt[i] = blkg_rwstat_read_counter(rwstat, i);
+ }
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(blkg_rwstat_recursive_sum);
diff --git a/block/blk-cgroup-rwstat.h b/block/blk-cgroup-rwstat.h
new file mode 100644
index 000000000000..ee746919c41f
--- /dev/null
+++ b/block/blk-cgroup-rwstat.h
@@ -0,0 +1,149 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Legacy blkg rwstat helpers enabled by CONFIG_BLK_CGROUP_RWSTAT.
+ * Do not use in new code.
+ */
+#ifndef _BLK_CGROUP_RWSTAT_H
+#define _BLK_CGROUP_RWSTAT_H
+
+#include <linux/blk-cgroup.h>
+
+enum blkg_rwstat_type {
+ BLKG_RWSTAT_READ,
+ BLKG_RWSTAT_WRITE,
+ BLKG_RWSTAT_SYNC,
+ BLKG_RWSTAT_ASYNC,
+ BLKG_RWSTAT_DISCARD,
+
+ BLKG_RWSTAT_NR,
+ BLKG_RWSTAT_TOTAL = BLKG_RWSTAT_NR,
+};
+
+/*
+ * blkg_[rw]stat->aux_cnt is excluded for local stats but included for
+ * recursive. Used to carry stats of dead children.
+ */
+struct blkg_rwstat {
+ struct percpu_counter cpu_cnt[BLKG_RWSTAT_NR];
+ atomic64_t aux_cnt[BLKG_RWSTAT_NR];
+};
+
+struct blkg_rwstat_sample {
+ u64 cnt[BLKG_RWSTAT_NR];
+};
+
+static inline u64 blkg_rwstat_read_counter(struct blkg_rwstat *rwstat,
+ unsigned int idx)
+{
+ return atomic64_read(&rwstat->aux_cnt[idx]) +
+ percpu_counter_sum_positive(&rwstat->cpu_cnt[idx]);
+}
+
+int blkg_rwstat_init(struct blkg_rwstat *rwstat, gfp_t gfp);
+void blkg_rwstat_exit(struct blkg_rwstat *rwstat);
+u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
+ const struct blkg_rwstat_sample *rwstat);
+u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
+ int off);
+void blkg_rwstat_recursive_sum(struct blkcg_gq *blkg, struct blkcg_policy *pol,
+ int off, struct blkg_rwstat_sample *sum);
+
+
+/**
+ * blkg_rwstat_add - add a value to a blkg_rwstat
+ * @rwstat: target blkg_rwstat
+ * @op: REQ_OP and flags
+ * @val: value to add
+ *
+ * Add @val to @rwstat. The counters are chosen according to @rw. The
+ * caller is responsible for synchronizing calls to this function.
+ */
+static inline void blkg_rwstat_add(struct blkg_rwstat *rwstat,
+ unsigned int op, uint64_t val)
+{
+ struct percpu_counter *cnt;
+
+ if (op_is_discard(op))
+ cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_DISCARD];
+ else if (op_is_write(op))
+ cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_WRITE];
+ else
+ cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_READ];
+
+ percpu_counter_add_batch(cnt, val, BLKG_STAT_CPU_BATCH);
+
+ if (op_is_sync(op))
+ cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_SYNC];
+ else
+ cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_ASYNC];
+
+ percpu_counter_add_batch(cnt, val, BLKG_STAT_CPU_BATCH);
+}
+
+/**
+ * blkg_rwstat_read - read the current values of a blkg_rwstat
+ * @rwstat: blkg_rwstat to read
+ *
+ * Read the current snapshot of @rwstat and return it in the aux counts.
+ */
+static inline void blkg_rwstat_read(struct blkg_rwstat *rwstat,
+ struct blkg_rwstat_sample *result)
+{
+ int i;
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++)
+ result->cnt[i] =
+ percpu_counter_sum_positive(&rwstat->cpu_cnt[i]);
+}
+
+/**
+ * blkg_rwstat_total - read the total count of a blkg_rwstat
+ * @rwstat: blkg_rwstat to read
+ *
+ * Return the total count of @rwstat regardless of the IO direction. This
+ * function can be called without synchronization and takes care of u64
+ * atomicity.
+ */
+static inline uint64_t blkg_rwstat_total(struct blkg_rwstat *rwstat)
+{
+ struct blkg_rwstat_sample tmp = { };
+
+ blkg_rwstat_read(rwstat, &tmp);
+ return tmp.cnt[BLKG_RWSTAT_READ] + tmp.cnt[BLKG_RWSTAT_WRITE];
+}
+
+/**
+ * blkg_rwstat_reset - reset a blkg_rwstat
+ * @rwstat: blkg_rwstat to reset
+ */
+static inline void blkg_rwstat_reset(struct blkg_rwstat *rwstat)
+{
+ int i;
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++) {
+ percpu_counter_set(&rwstat->cpu_cnt[i], 0);
+ atomic64_set(&rwstat->aux_cnt[i], 0);
+ }
+}
+
+/**
+ * blkg_rwstat_add_aux - add a blkg_rwstat into another's aux count
+ * @to: the destination blkg_rwstat
+ * @from: the source
+ *
+ * Add @from's count including the aux one to @to's aux count.
+ */
+static inline void blkg_rwstat_add_aux(struct blkg_rwstat *to,
+ struct blkg_rwstat *from)
+{
+ u64 sum[BLKG_RWSTAT_NR];
+ int i;
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++)
+ sum[i] = percpu_counter_sum_positive(&from->cpu_cnt[i]);
+
+ for (i = 0; i < BLKG_RWSTAT_NR; i++)
+ atomic64_add(sum[i] + atomic64_read(&from->aux_cnt[i]),
+ &to->aux_cnt[i]);
+}
+#endif /* _BLK_CGROUP_RWSTAT_H */
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 0b349f6a6a69..d0b9bfa563eb 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -561,103 +561,6 @@ u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v)
}
EXPORT_SYMBOL_GPL(__blkg_prfill_u64);
-/**
- * __blkg_prfill_rwstat - prfill helper for a blkg_rwstat
- * @sf: seq_file to print to
- * @pd: policy private data of interest
- * @rwstat: rwstat to print
- *
- * Print @rwstat to @sf for the device assocaited with @pd.
- */
-u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
- const struct blkg_rwstat_sample *rwstat)
-{
- static const char *rwstr[] = {
- [BLKG_RWSTAT_READ] = "Read",
- [BLKG_RWSTAT_WRITE] = "Write",
- [BLKG_RWSTAT_SYNC] = "Sync",
- [BLKG_RWSTAT_ASYNC] = "Async",
- [BLKG_RWSTAT_DISCARD] = "Discard",
- };
- const char *dname = blkg_dev_name(pd->blkg);
- u64 v;
- int i;
-
- if (!dname)
- return 0;
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++)
- seq_printf(sf, "%s %s %llu\n", dname, rwstr[i],
- rwstat->cnt[i]);
-
- v = rwstat->cnt[BLKG_RWSTAT_READ] +
- rwstat->cnt[BLKG_RWSTAT_WRITE] +
- rwstat->cnt[BLKG_RWSTAT_DISCARD];
- seq_printf(sf, "%s Total %llu\n", dname, v);
- return v;
-}
-EXPORT_SYMBOL_GPL(__blkg_prfill_rwstat);
-
-/**
- * blkg_prfill_rwstat - prfill callback for blkg_rwstat
- * @sf: seq_file to print to
- * @pd: policy private data of interest
- * @off: offset to the blkg_rwstat in @pd
- *
- * prfill callback for printing a blkg_rwstat.
- */
-u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
- int off)
-{
- struct blkg_rwstat_sample rwstat = { };
-
- blkg_rwstat_read((void *)pd + off, &rwstat);
- return __blkg_prfill_rwstat(sf, pd, &rwstat);
-}
-EXPORT_SYMBOL_GPL(blkg_prfill_rwstat);
-
-/**
- * blkg_rwstat_recursive_sum - collect hierarchical blkg_rwstat
- * @blkg: blkg of interest
- * @pol: blkcg_policy which contains the blkg_rwstat
- * @off: offset to the blkg_rwstat in blkg_policy_data or @blkg
- * @sum: blkg_rwstat_sample structure containing the results
- *
- * Collect the blkg_rwstat specified by @blkg, @pol and @off and all its
- * online descendants and their aux counts. The caller must be holding the
- * queue lock for online tests.
- *
- * If @pol is NULL, blkg_rwstat is at @off bytes into @blkg; otherwise, it
- * is at @off bytes into @blkg's blkg_policy_data of the policy.
- */
-void blkg_rwstat_recursive_sum(struct blkcg_gq *blkg, struct blkcg_policy *pol,
- int off, struct blkg_rwstat_sample *sum)
-{
- struct blkcg_gq *pos_blkg;
- struct cgroup_subsys_state *pos_css;
- unsigned int i;
-
- lockdep_assert_held(&blkg->q->queue_lock);
-
- rcu_read_lock();
- blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) {
- struct blkg_rwstat *rwstat;
-
- if (!pos_blkg->online)
- continue;
-
- if (pol)
- rwstat = (void *)blkg_to_pd(pos_blkg, pol) + off;
- else
- rwstat = (void *)pos_blkg + off;
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++)
- sum->cnt[i] = blkg_rwstat_read_counter(rwstat, i);
- }
- rcu_read_unlock();
-}
-EXPORT_SYMBOL_GPL(blkg_rwstat_recursive_sum);
-
/* Performs queue bypass and policy enabled checks then looks up blkg. */
static struct blkcg_gq *blkg_lookup_check(struct blkcg *blkcg,
const struct blkcg_policy *pol,
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 6ac5b5d56170..ae1f73a92e12 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -12,6 +12,7 @@
#include <linux/blktrace_api.h>
#include <linux/blk-cgroup.h>
#include "blk.h"
+#include "blk-cgroup-rwstat.h"
/* Max dispatch from a group in 1 round */
static int throtl_grp_quantum = 8;
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index 867ab391e409..48a66738143d 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -41,17 +41,6 @@ enum blkg_iostat_type {
BLKG_IOSTAT_NR,
};
-enum blkg_rwstat_type {
- BLKG_RWSTAT_READ,
- BLKG_RWSTAT_WRITE,
- BLKG_RWSTAT_SYNC,
- BLKG_RWSTAT_ASYNC,
- BLKG_RWSTAT_DISCARD,
-
- BLKG_RWSTAT_NR,
- BLKG_RWSTAT_TOTAL = BLKG_RWSTAT_NR,
-};
-
struct blkcg_gq;
struct blkcg {
@@ -82,19 +71,6 @@ struct blkg_iostat_set {
struct blkg_iostat last;
};
-/*
- * blkg_[rw]stat->aux_cnt is excluded for local stats but included for
- * recursive. Used to carry stats of dead children.
- */
-struct blkg_rwstat {
- struct percpu_counter cpu_cnt[BLKG_RWSTAT_NR];
- atomic64_t aux_cnt[BLKG_RWSTAT_NR];
-};
-
-struct blkg_rwstat_sample {
- u64 cnt[BLKG_RWSTAT_NR];
-};
-
/*
* A blkcg_gq (blkg) is association between a block cgroup (blkcg) and a
* request_queue (q). This is used by blkcg policies which need to track
@@ -223,13 +199,6 @@ int blkcg_activate_policy(struct request_queue *q,
void blkcg_deactivate_policy(struct request_queue *q,
const struct blkcg_policy *pol);
-static inline u64 blkg_rwstat_read_counter(struct blkg_rwstat *rwstat,
- unsigned int idx)
-{
- return atomic64_read(&rwstat->aux_cnt[idx]) +
- percpu_counter_sum_positive(&rwstat->cpu_cnt[idx]);
-}
-
const char *blkg_dev_name(struct blkcg_gq *blkg);
void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,
u64 (*prfill)(struct seq_file *,
@@ -237,12 +206,6 @@ void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,
const struct blkcg_policy *pol, int data,
bool show_total);
u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v);
-u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
- const struct blkg_rwstat_sample *rwstat);
-u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
- int off);
-void blkg_rwstat_recursive_sum(struct blkcg_gq *blkg, struct blkcg_policy *pol,
- int off, struct blkg_rwstat_sample *sum);
struct blkg_conf_ctx {
struct gendisk *disk;
@@ -594,128 +557,6 @@ static inline void blkg_put(struct blkcg_gq *blkg)
if (((d_blkg) = __blkg_lookup(css_to_blkcg(pos_css), \
(p_blkg)->q, false)))
-static inline int blkg_rwstat_init(struct blkg_rwstat *rwstat, gfp_t gfp)
-{
- int i, ret;
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++) {
- ret = percpu_counter_init(&rwstat->cpu_cnt[i], 0, gfp);
- if (ret) {
- while (--i >= 0)
- percpu_counter_destroy(&rwstat->cpu_cnt[i]);
- return ret;
- }
- atomic64_set(&rwstat->aux_cnt[i], 0);
- }
- return 0;
-}
-
-static inline void blkg_rwstat_exit(struct blkg_rwstat *rwstat)
-{
- int i;
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++)
- percpu_counter_destroy(&rwstat->cpu_cnt[i]);
-}
-
-/**
- * blkg_rwstat_add - add a value to a blkg_rwstat
- * @rwstat: target blkg_rwstat
- * @op: REQ_OP and flags
- * @val: value to add
- *
- * Add @val to @rwstat. The counters are chosen according to @rw. The
- * caller is responsible for synchronizing calls to this function.
- */
-static inline void blkg_rwstat_add(struct blkg_rwstat *rwstat,
- unsigned int op, uint64_t val)
-{
- struct percpu_counter *cnt;
-
- if (op_is_discard(op))
- cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_DISCARD];
- else if (op_is_write(op))
- cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_WRITE];
- else
- cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_READ];
-
- percpu_counter_add_batch(cnt, val, BLKG_STAT_CPU_BATCH);
-
- if (op_is_sync(op))
- cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_SYNC];
- else
- cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_ASYNC];
-
- percpu_counter_add_batch(cnt, val, BLKG_STAT_CPU_BATCH);
-}
-
-/**
- * blkg_rwstat_read - read the current values of a blkg_rwstat
- * @rwstat: blkg_rwstat to read
- *
- * Read the current snapshot of @rwstat and return it in the aux counts.
- */
-static inline void blkg_rwstat_read(struct blkg_rwstat *rwstat,
- struct blkg_rwstat_sample *result)
-{
- int i;
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++)
- result->cnt[i] =
- percpu_counter_sum_positive(&rwstat->cpu_cnt[i]);
-}
-
-/**
- * blkg_rwstat_total - read the total count of a blkg_rwstat
- * @rwstat: blkg_rwstat to read
- *
- * Return the total count of @rwstat regardless of the IO direction. This
- * function can be called without synchronization and takes care of u64
- * atomicity.
- */
-static inline uint64_t blkg_rwstat_total(struct blkg_rwstat *rwstat)
-{
- struct blkg_rwstat_sample tmp = { };
-
- blkg_rwstat_read(rwstat, &tmp);
- return tmp.cnt[BLKG_RWSTAT_READ] + tmp.cnt[BLKG_RWSTAT_WRITE];
-}
-
-/**
- * blkg_rwstat_reset - reset a blkg_rwstat
- * @rwstat: blkg_rwstat to reset
- */
-static inline void blkg_rwstat_reset(struct blkg_rwstat *rwstat)
-{
- int i;
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++) {
- percpu_counter_set(&rwstat->cpu_cnt[i], 0);
- atomic64_set(&rwstat->aux_cnt[i], 0);
- }
-}
-
-/**
- * blkg_rwstat_add_aux - add a blkg_rwstat into another's aux count
- * @to: the destination blkg_rwstat
- * @from: the source
- *
- * Add @from's count including the aux one to @to's aux count.
- */
-static inline void blkg_rwstat_add_aux(struct blkg_rwstat *to,
- struct blkg_rwstat *from)
-{
- u64 sum[BLKG_RWSTAT_NR];
- int i;
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++)
- sum[i] = percpu_counter_sum_positive(&from->cpu_cnt[i]);
-
- for (i = 0; i < BLKG_RWSTAT_NR; i++)
- atomic64_add(sum[i] + atomic64_read(&from->aux_cnt[i]),
- &to->aux_cnt[i]);
-}
-
#ifdef CONFIG_BLK_DEV_THROTTLING
extern bool blk_throtl_bio(struct request_queue *q, struct blkcg_gq *blkg,
struct bio *bio);
--
2.17.1