From: Daeho Jeong <daehoje...@google.com>

Added "ckpt_thread_ioprio" sysfs node to give a way to change checkpoint
merge daemon's io priority. Its default value is "be,3", which means
"BE" I/O class and I/O priority "3". We can select the class between "rt"
and "be", and set the I/O priority within valid range of it.
"," delimiter is necessary in between I/O class and priority number.

Signed-off-by: Daeho Jeong <daehoje...@google.com>
---
 Documentation/ABI/testing/sysfs-fs-f2fs |  8 ++++
 fs/f2fs/checkpoint.c                    |  3 +-
 fs/f2fs/f2fs.h                          |  1 +
 fs/f2fs/sysfs.c                         | 51 +++++++++++++++++++++++++
 4 files changed, 62 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs 
b/Documentation/ABI/testing/sysfs-fs-f2fs
index 3dfee94e0618..0c48b2e7dfd4 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -377,3 +377,11 @@ Description:       This gives a control to limit the bio 
size in f2fs.
                Default is zero, which will follow underlying block layer limit,
                whereas, if it has a certain bytes value, f2fs won't submit a
                bio larger than that size.
+What:          /sys/fs/f2fs/<disk>/ckpt_thread_ioprio
+Date:          January 2021
+Contact:       "Daeho Jeong" <daehoje...@google.com>
+Description:   Give a way to change checkpoint merge daemon's io priority.
+               Its default value is "be,3", which means "BE" I/O class and
+               I/O priority "3". We can select the class between "rt" and "be",
+               and set the I/O priority within valid range of it. "," delimiter
+               is necessary in between I/O class and priority number.
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 11288f435dbe..37a393f97d5d 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1839,6 +1839,7 @@ int f2fs_create_ckpt_req_control(struct f2fs_sb_info *sbi)
        atomic_set(&cprc->issued_ckpt, 0);
        atomic_set(&cprc->total_ckpt, 0);
        atomic_set(&cprc->queued_ckpt, 0);
+       cprc->ckpt_thread_ioprio = DEFAULT_CHECKPOINT_IOPRIO;
        init_waitqueue_head(&cprc->ckpt_wait_queue);
        init_llist_head(&cprc->issue_list);
        sbi->cprc_info = cprc;
@@ -1859,7 +1860,7 @@ int f2fs_create_ckpt_req_control(struct f2fs_sb_info *sbi)
                return err;
        }
 
-       set_task_ioprio(cprc->f2fs_issue_ckpt, DEFAULT_CHECKPOINT_IOPRIO);
+       set_task_ioprio(cprc->f2fs_issue_ckpt, cprc->ckpt_thread_ioprio);
 
        return 0;
 }
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 4de5285df17d..957bf4c42d40 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -278,6 +278,7 @@ struct ckpt_req {
 
 struct ckpt_req_control {
        struct task_struct *f2fs_issue_ckpt;    /* checkpoint task */
+       int ckpt_thread_ioprio;                 /* checkpoint merge thread 
ioprio */
        wait_queue_head_t ckpt_wait_queue;      /* waiting queue for wake-up */
        atomic_t issued_ckpt;                   /* # of actually issued ckpts */
        atomic_t total_ckpt;                    /* # of total ckpts */
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 30bae57428d1..295ebd84986b 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -11,6 +11,7 @@
 #include <linux/f2fs_fs.h>
 #include <linux/seq_file.h>
 #include <linux/unicode.h>
+#include <linux/ioprio.h>
 
 #include "f2fs.h"
 #include "segment.h"
@@ -34,6 +35,7 @@ enum {
        FAULT_INFO_TYPE,        /* struct f2fs_fault_info */
 #endif
        RESERVED_BLOCKS,        /* struct f2fs_sb_info */
+       CPRC_INFO,      /* struct ckpt_req_control */
 };
 
 struct f2fs_attr {
@@ -70,6 +72,8 @@ static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, 
int struct_type)
        else if (struct_type == STAT_INFO)
                return (unsigned char *)F2FS_STAT(sbi);
 #endif
+       else if (struct_type == CPRC_INFO)
+               return (unsigned char *)sbi->cprc_info;
        return NULL;
 }
 
@@ -255,6 +259,23 @@ static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
                return len;
        }
 
+       if (!strcmp(a->attr.name, "ckpt_thread_ioprio")) {
+               struct ckpt_req_control *cprc = sbi->cprc_info;
+               int len = 0;
+               int class = IOPRIO_PRIO_CLASS(cprc->ckpt_thread_ioprio);
+               int data = IOPRIO_PRIO_DATA(cprc->ckpt_thread_ioprio);
+
+               if (class == IOPRIO_CLASS_RT)
+                       len += scnprintf(buf + len, PAGE_SIZE - len, "rt,");
+               else if (class == IOPRIO_CLASS_BE)
+                       len += scnprintf(buf + len, PAGE_SIZE - len, "be,");
+               else
+                       return -EINVAL;
+
+               len += scnprintf(buf + len, PAGE_SIZE - len, "%d\n", data);
+               return len;
+       }
+
        ui = (unsigned int *)(ptr + a->offset);
 
        return sprintf(buf, "%u\n", *ui);
@@ -308,6 +329,34 @@ static ssize_t __sbi_store(struct f2fs_attr *a,
                return ret ? ret : count;
        }
 
+       if (!strcmp(a->attr.name, "ckpt_thread_ioprio")) {
+               const char *name = strim((char *)buf);
+               struct ckpt_req_control *cprc = sbi->cprc_info;
+               int class;
+               long data;
+               int ret;
+
+               if (!strncmp(name, "rt,", 3))
+                       class = IOPRIO_CLASS_RT;
+               else if (!strncmp(name, "be,", 3))
+                       class = IOPRIO_CLASS_BE;
+               else
+                       return -EINVAL;
+
+               name += 3;
+               ret = kstrtol(name, 10, &data);
+               if (ret)
+                       return ret;
+               if (data >= IOPRIO_BE_NR || data < 0)
+                       return -EINVAL;
+
+               cprc->ckpt_thread_ioprio = IOPRIO_PRIO_VALUE(class, data);
+               ret = set_task_ioprio(cprc->f2fs_issue_ckpt,
+                               cprc->ckpt_thread_ioprio);
+
+               return count;
+       }
+
        ui = (unsigned int *)(ptr + a->offset);
 
        ret = kstrtoul(skip_spaces(buf), 0, &t);
@@ -567,6 +616,7 @@ F2FS_RW_ATTR(FAULT_INFO_TYPE, f2fs_fault_info, inject_type, 
inject_type);
 #endif
 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, data_io_flag, data_io_flag);
 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, node_io_flag, node_io_flag);
+F2FS_RW_ATTR(CPRC_INFO, ckpt_req_control, ckpt_thread_ioprio, 
ckpt_thread_ioprio);
 F2FS_GENERAL_RO_ATTR(dirty_segments);
 F2FS_GENERAL_RO_ATTR(free_segments);
 F2FS_GENERAL_RO_ATTR(lifetime_write_kbytes);
@@ -652,6 +702,7 @@ static struct attribute *f2fs_attrs[] = {
 #endif
        ATTR_LIST(data_io_flag),
        ATTR_LIST(node_io_flag),
+       ATTR_LIST(ckpt_thread_ioprio),
        ATTR_LIST(dirty_segments),
        ATTR_LIST(free_segments),
        ATTR_LIST(unusable),
-- 
2.30.0.284.gd98b1dd5eaa7-goog

Reply via email to