zram: remove obsolete sysfs attrs (c87d1655) · Commits · 戴 / test

Documentation/ABI/obsolete/sysfs-block-zram

deleted100644 → 0

+0 −119

Original line number	Diff line number	Diff line
		What: /sys/block/zram<id>/num_reads
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The num_reads file is read-only and specifies the number of
		reads (failed or successful) done on this device.
		Now accessible via zram<id>/stat node.

		What: /sys/block/zram<id>/num_writes
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The num_writes file is read-only and specifies the number of
		writes (failed or successful) done on this device.
		Now accessible via zram<id>/stat node.

		What: /sys/block/zram<id>/invalid_io
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The invalid_io file is read-only and specifies the number of
		non-page-size-aligned I/O requests issued to this device.
		Now accessible via zram<id>/io_stat node.

		What: /sys/block/zram<id>/failed_reads
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The failed_reads file is read-only and specifies the number of
		failed reads happened on this device.
		Now accessible via zram<id>/io_stat node.

		What: /sys/block/zram<id>/failed_writes
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The failed_writes file is read-only and specifies the number of
		failed writes happened on this device.
		Now accessible via zram<id>/io_stat node.

		What: /sys/block/zram<id>/notify_free
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The notify_free file is read-only. Depending on device usage
		scenario it may account a) the number of pages freed because
		of swap slot free notifications or b) the number of pages freed
		because of REQ_DISCARD requests sent by bio. The former ones
		are sent to a swap block device when a swap slot is freed, which
		implies that this disk is being used as a swap disk. The latter
		ones are sent by filesystem mounted with discard option,
		whenever some data blocks are getting discarded.
		Now accessible via zram<id>/io_stat node.

		What: /sys/block/zram<id>/zero_pages
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The zero_pages file is read-only and specifies number of zero
		filled pages written to this disk. No memory is allocated for
		such pages.
		Now accessible via zram<id>/mm_stat node.

		What: /sys/block/zram<id>/orig_data_size
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The orig_data_size file is read-only and specifies uncompressed
		size of data stored in this disk. This excludes zero-filled
		pages (zero_pages) since no memory is allocated for them.
		Unit: bytes
		Now accessible via zram<id>/mm_stat node.

		What: /sys/block/zram<id>/compr_data_size
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The compr_data_size file is read-only and specifies compressed
		size of data stored in this disk. So, compression ratio can be
		calculated using orig_data_size and this statistic.
		Unit: bytes
		Now accessible via zram<id>/mm_stat node.

		What: /sys/block/zram<id>/mem_used_total
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The mem_used_total file is read-only and specifies the amount
		of memory, including allocator fragmentation and metadata
		overhead, allocated for this disk. So, allocator space
		efficiency can be calculated using compr_data_size and this
		statistic.
		Unit: bytes
		Now accessible via zram<id>/mm_stat node.

		What: /sys/block/zram<id>/mem_used_max
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The mem_used_max file is read/write and specifies the amount
		of maximum memory zram have consumed to store compressed data.
		For resetting the value, you should write "0". Otherwise,
		you could see -EINVAL.
		Unit: bytes
		Downgraded to write-only node: so it's possible to set new
		value only; its current value is stored in zram<id>/mm_stat
		node.

		What: /sys/block/zram<id>/mem_limit
		Date: August 2015
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The mem_limit file is read/write and specifies the maximum
		amount of memory ZRAM can use to store the compressed data.
		The limit could be changed in run time and "0" means disable
		the limit. No limit is the initial state. Unit: bytes
		Downgraded to write-only node: so it's possible to set new
		value only; its current value is stored in zram<id>/mm_stat
		node.

Documentation/ABI/testing/sysfs-block-zram

+8 −93

Original line number	Diff line number	Diff line
		@@ -22,41 +22,6 @@ Description:
		device. The reset operation frees all the memory associated
		with this device.

		What: /sys/block/zram<id>/num_reads
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The num_reads file is read-only and specifies the number of
		reads (failed or successful) done on this device.

		What: /sys/block/zram<id>/num_writes
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The num_writes file is read-only and specifies the number of
		writes (failed or successful) done on this device.

		What: /sys/block/zram<id>/invalid_io
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The invalid_io file is read-only and specifies the number of
		non-page-size-aligned I/O requests issued to this device.

		What: /sys/block/zram<id>/failed_reads
		Date: February 2014
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The failed_reads file is read-only and specifies the number of
		failed reads happened on this device.

		What: /sys/block/zram<id>/failed_writes
		Date: February 2014
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		Description:
		The failed_writes file is read-only and specifies the number of
		failed writes happened on this device.

		What: /sys/block/zram<id>/max_comp_streams
		Date: February 2014
		Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
		@@ -73,74 +38,24 @@ Description:
		available and selected compression algorithms, change
		compression algorithm selection.

		What: /sys/block/zram<id>/notify_free
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The notify_free file is read-only. Depending on device usage
		scenario it may account a) the number of pages freed because
		of swap slot free notifications or b) the number of pages freed
		because of REQ_DISCARD requests sent by bio. The former ones
		are sent to a swap block device when a swap slot is freed, which
		implies that this disk is being used as a swap disk. The latter
		ones are sent by filesystem mounted with discard option,
		whenever some data blocks are getting discarded.

		What: /sys/block/zram<id>/zero_pages
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The zero_pages file is read-only and specifies number of zero
		filled pages written to this disk. No memory is allocated for
		such pages.

		What: /sys/block/zram<id>/orig_data_size
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The orig_data_size file is read-only and specifies uncompressed
		size of data stored in this disk. This excludes zero-filled
		pages (zero_pages) since no memory is allocated for them.
		Unit: bytes

		What: /sys/block/zram<id>/compr_data_size
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The compr_data_size file is read-only and specifies compressed
		size of data stored in this disk. So, compression ratio can be
		calculated using orig_data_size and this statistic.
		Unit: bytes

		What: /sys/block/zram<id>/mem_used_total
		Date: August 2010
		Contact: Nitin Gupta <ngupta@vflare.org>
		Description:
		The mem_used_total file is read-only and specifies the amount
		of memory, including allocator fragmentation and metadata
		overhead, allocated for this disk. So, allocator space
		efficiency can be calculated using compr_data_size and this
		statistic.
		Unit: bytes

		What: /sys/block/zram<id>/mem_used_max
		Date: August 2014
		Contact: Minchan Kim <minchan@kernel.org>
		Description:
		The mem_used_max file is read/write and specifies the amount
		of maximum memory zram have consumed to store compressed data.
		For resetting the value, you should write "0". Otherwise,
		you could see -EINVAL.
		The mem_used_max file is write-only and is used to reset
		the counter of maximum memory zram have consumed to store
		compressed data. For resetting the value, you should write
		"0". Otherwise, you could see -EINVAL.
		Unit: bytes

		What: /sys/block/zram<id>/mem_limit
		Date: August 2014
		Contact: Minchan Kim <minchan@kernel.org>
		Description:
		The mem_limit file is read/write and specifies the maximum
		amount of memory ZRAM can use to store the compressed data. The
		limit could be changed in run time and "0" means disable the
		limit. No limit is the initial state. Unit: bytes
		The mem_limit file is write-only and specifies the maximum
		amount of memory ZRAM can use to store the compressed data.
		The limit could be changed in run time and "0" means disable
		the limit. No limit is the initial state. Unit: bytes

		What: /sys/block/zram<id>/compact
		Date: August 2015

Documentation/blockdev/zram.txt

+32 −42

Original line number	Diff line number	Diff line
		@@ -161,42 +161,14 @@ Name access description
		disksize RW show and set the device's disk size
		initstate RO shows the initialization state of the device
		reset WO trigger device reset
		num_reads RO the number of reads
		failed_reads RO the number of failed reads
		num_write RO the number of writes
		failed_writes RO the number of failed writes
		invalid_io RO the number of non-page-size-aligned I/O requests
		mem_used_max WO reset the `mem_used_max' counter (see later)
		mem_limit WO specifies the maximum amount of memory ZRAM can use
		to store the compressed data
		max_comp_streams RW the number of possible concurrent compress operations
		comp_algorithm RW show and change the compression algorithm
		notify_free RO the number of notifications to free pages (either
		slot free notifications or REQ_DISCARD requests)
		zero_pages RO the number of zero filled pages written to this disk
		orig_data_size RO uncompressed size of data stored in this disk
		compr_data_size RO compressed size of data stored in this disk
		mem_used_total RO the amount of memory allocated for this disk
		mem_used_max RW the maximum amount of memory zram have consumed to
		store the data (to reset this counter to the actual
		current value, write 1 to this attribute)
		mem_limit RW the maximum amount of memory ZRAM can use to store
		the compressed data
		pages_compacted RO the number of pages freed during compaction
		(available only via zram<id>/mm_stat node)
		compact WO trigger memory compaction
		debug_stat RO this file is used for zram debugging purposes

		WARNING
		=======
		per-stat sysfs attributes are considered to be deprecated.
		The basic strategy is:
		-- the existing RW nodes will be downgraded to WO nodes (in linux 4.11)
		-- deprecated RO sysfs nodes will eventually be removed (in linux 4.11)

		The list of deprecated attributes can be found here:
		Documentation/ABI/obsolete/sysfs-block-zram

		Basically, every attribute that has its own read accessible sysfs node
		(e.g. num_reads) AND is accessible via one of the stat files (zram<id>/stat
		or zram<id>/io_stat or zram<id>/mm_stat) is considered to be deprecated.

		User space is advised to use the following files to read the device statistics.

		@@ -211,22 +183,40 @@ The stat file represents device's I/O statistics not accounted by block
		layer and, thus, not available in zram<id>/stat file. It consists of a
		single line of text and contains the following stats separated by
		whitespace:
		failed_reads
		failed_writes
		invalid_io
		notify_free
		failed_reads the number of failed reads
		failed_writes the number of failed writes
		invalid_io the number of non-page-size-aligned I/O requests
		notify_free Depending on device usage scenario it may account
		a) the number of pages freed because of swap slot free
		notifications or b) the number of pages freed because of
		REQ_DISCARD requests sent by bio. The former ones are
		sent to a swap block device when a swap slot is freed,
		which implies that this disk is being used as a swap disk.
		The latter ones are sent by filesystem mounted with
		discard option, whenever some data blocks are getting
		discarded.

		File /sys/block/zram<id>/mm_stat

		The stat file represents device's mm statistics. It consists of a single
		line of text and contains the following stats separated by whitespace:
		orig_data_size
		compr_data_size
		mem_used_total
		mem_limit
		mem_used_max
		zero_pages
		num_migrated
		orig_data_size uncompressed size of data stored in this disk.
		This excludes zero-filled pages (zero_pages) since no
		memory is allocated for them.
		Unit: bytes
		compr_data_size compressed size of data stored in this disk
		mem_used_total the amount of memory allocated for this disk. This
		includes allocator fragmentation and metadata overhead,
		allocated for this disk. So, allocator space efficiency
		can be calculated using compr_data_size and this statistic.
		Unit: bytes
		mem_limit the maximum amount of memory ZRAM can use to store
		the compressed data
		mem_used_max the maximum amount of memory zram have consumed to
		store the data
		zero_pages the number of zero filled pages written to this disk.
		No memory is allocated for such pages.
		pages_compacted the number of pages freed during compaction

		9) Deactivate:
		swapoff /dev/zram0

drivers/block/zram/zram_drv.c

+2 −99

Original line number	Diff line number	Diff line
		@@ -45,27 +45,6 @@ static const char *default_compressor = "lzo";
		/* Module params (documentation at end) */
		static unsigned int num_devices = 1;

		static inline void deprecated_attr_warn(const char *name)
		{
		pr_warn_once("%d (%s) Attribute %s (and others) will be removed. %s\n",
		task_pid_nr(current),
		current->comm,
		name,
		"See zram documentation.");
		}

		#define ZRAM_ATTR_RO(name) \
		static ssize_t name##_show(struct device *d, \
		struct device_attribute attr, char b) \
		{ \
		struct zram *zram = dev_to_zram(d); \
		\
		deprecated_attr_warn(__stringify(name)); \
		return scnprintf(b, PAGE_SIZE, "%llu\n", \
		(u64)atomic64_read(&zram->stats.name)); \
		} \
		static DEVICE_ATTR_RO(name);

		static inline bool init_done(struct zram *zram)
		{
		return zram->disksize;
		@@ -218,47 +197,6 @@ static ssize_t disksize_show(struct device *dev,
		return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize);
		}

		static ssize_t orig_data_size_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		struct zram *zram = dev_to_zram(dev);

		deprecated_attr_warn("orig_data_size");
		return scnprintf(buf, PAGE_SIZE, "%llu\n",
		(u64)(atomic64_read(&zram->stats.pages_stored)) << PAGE_SHIFT);
		}

		static ssize_t mem_used_total_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		u64 val = 0;
		struct zram *zram = dev_to_zram(dev);

		deprecated_attr_warn("mem_used_total");
		down_read(&zram->init_lock);
		if (init_done(zram)) {
		struct zram_meta *meta = zram->meta;
		val = zs_get_total_pages(meta->mem_pool);
		}
		up_read(&zram->init_lock);

		return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT);
		}

		static ssize_t mem_limit_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		u64 val;
		struct zram *zram = dev_to_zram(dev);

		deprecated_attr_warn("mem_limit");
		down_read(&zram->init_lock);
		val = zram->limit_pages;
		up_read(&zram->init_lock);

		return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT);
		}

		static ssize_t mem_limit_store(struct device *dev,
		struct device_attribute attr, const char buf, size_t len)
		{
		@@ -277,21 +215,6 @@ static ssize_t mem_limit_store(struct device *dev,
		return len;
		}

		static ssize_t mem_used_max_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		u64 val = 0;
		struct zram *zram = dev_to_zram(dev);

		deprecated_attr_warn("mem_used_max");
		down_read(&zram->init_lock);
		if (init_done(zram))
		val = atomic_long_read(&zram->stats.max_used_pages);
		up_read(&zram->init_lock);

		return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT);
		}

		static ssize_t mem_used_max_store(struct device *dev,
		struct device_attribute attr, const char buf, size_t len)
		{
		@@ -467,14 +390,6 @@ static ssize_t debug_stat_show(struct device *dev,
		static DEVICE_ATTR_RO(io_stat);
		static DEVICE_ATTR_RO(mm_stat);
		static DEVICE_ATTR_RO(debug_stat);
		ZRAM_ATTR_RO(num_reads);
		ZRAM_ATTR_RO(num_writes);
		ZRAM_ATTR_RO(failed_reads);
		ZRAM_ATTR_RO(failed_writes);
		ZRAM_ATTR_RO(invalid_io);
		ZRAM_ATTR_RO(notify_free);
		ZRAM_ATTR_RO(zero_pages);
		ZRAM_ATTR_RO(compr_data_size);

		static inline bool zram_meta_get(struct zram *zram)
		{
		@@ -1188,10 +1103,8 @@ static DEVICE_ATTR_WO(compact);
		static DEVICE_ATTR_RW(disksize);
		static DEVICE_ATTR_RO(initstate);
		static DEVICE_ATTR_WO(reset);
		static DEVICE_ATTR_RO(orig_data_size);
		static DEVICE_ATTR_RO(mem_used_total);
		static DEVICE_ATTR_RW(mem_limit);
		static DEVICE_ATTR_RW(mem_used_max);
		static DEVICE_ATTR_WO(mem_limit);
		static DEVICE_ATTR_WO(mem_used_max);
		static DEVICE_ATTR_RW(max_comp_streams);
		static DEVICE_ATTR_RW(comp_algorithm);

		@@ -1199,17 +1112,7 @@ static struct attribute *zram_disk_attrs[] = {
		&dev_attr_disksize.attr,
		&dev_attr_initstate.attr,
		&dev_attr_reset.attr,
		&dev_attr_num_reads.attr,
		&dev_attr_num_writes.attr,
		&dev_attr_failed_reads.attr,
		&dev_attr_failed_writes.attr,
		&dev_attr_compact.attr,
		&dev_attr_invalid_io.attr,
		&dev_attr_notify_free.attr,
		&dev_attr_zero_pages.attr,
		&dev_attr_orig_data_size.attr,
		&dev_attr_compr_data_size.attr,
		&dev_attr_mem_used_total.attr,
		&dev_attr_mem_limit.attr,
		&dev_attr_mem_used_max.attr,
		&dev_attr_max_comp_streams.attr,

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