Commit e6592066 authored by Daeho Jeong's avatar Daeho Jeong Committed by Jaegeuk Kim
Browse files

f2fs: add ckpt_thread_ioprio sysfs node 



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: default avatarDaeho Jeong <daehojeong@google.com>
Reviewed-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 261eeb9c

Documentation/ABI/testing/sysfs-fs-f2fs

+9 −0
Original line number Diff line number Diff line
@@ -400,3 +400,12 @@ Description: Show status of f2fs superblock in real time. 
		0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted

		0x2000 SBI_IS_RESIZEFS       resizefs is in process

		====== ===================== =================================



What:		/sys/fs/f2fs/<disk>/ckpt_thread_ioprio

Date:		January 2021

Contact:	"Daeho Jeong" <daehojeong@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.

fs/f2fs/checkpoint.c

+2 −1
Original line number Diff line number Diff line
@@ -1851,7 +1851,7 @@ int f2fs_start_ckpt_thread(struct f2fs_sb_info *sbi) 
		return -ENOMEM;

	}



	set_task_ioprio(cprc->f2fs_issue_ckpt, DEFAULT_CHECKPOINT_IOPRIO);

	set_task_ioprio(cprc->f2fs_issue_ckpt, cprc->ckpt_thread_ioprio);



	return 0;

}
@@ -1877,6 +1877,7 @@ void f2fs_init_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);

	spin_lock_init(&cprc->stat_lock);

fs/f2fs/f2fs.h

+1 −0
Original line number Diff line number Diff line
@@ -277,6 +277,7 @@ 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 */

fs/f2fs/sysfs.c

+55 −0
Original line number Diff line number Diff line
@@ -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;

}
@@ -261,6 +265,23 @@ 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);
@@ -314,6 +335,38 @@ 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);

		if (test_opt(sbi, MERGE_CHECKPOINT)) {

			ret = set_task_ioprio(cprc->f2fs_issue_ckpt,

					cprc->ckpt_thread_ioprio);

			if (ret)

				return ret;

		}



		return count;

	}



	ui = (unsigned int *)(ptr + a->offset);



	ret = kstrtoul(skip_spaces(buf), 0, &t);
@@ -573,6 +626,7 @@ 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);
@@ -658,6 +712,7 @@ 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),