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authorLinus Torvalds <torvalds@linux-foundation.org>2017-02-23 06:29:24 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-23 06:29:24 +0300
commitbc49a7831b1137ce1c2dda1c57e3631655f5d2ae (patch)
tree469380ac3a17e1d927ccf06abc99b6f509deb24a /Documentation
parentbe5165a51d2500ae1afa1236a8b09858831fdf7e (diff)
parentf201ebd87652cf1519792f8662bb3f862c76aa33 (diff)
downloadlinux-bc49a7831b1137ce1c2dda1c57e3631655f5d2ae.tar.xz
Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton: "142 patches: - DAX updates - various misc bits - OCFS2 updates - most of MM" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (142 commits) mm/z3fold.c: limit first_num to the actual range of possible buddy indexes mm: fix <linux/pagemap.h> stray kernel-doc notation zram: remove obsolete sysfs attrs mm/memblock.c: remove unnecessary log and clean up oom-reaper: use madvise_dontneed() logic to decide if unmap the VMA mm: drop unused argument of zap_page_range() mm: drop zap_details::check_swap_entries mm: drop zap_details::ignore_dirty mm, page_alloc: warn_alloc nodemask is NULL when cpusets are disabled mm: help __GFP_NOFAIL allocations which do not trigger OOM killer mm, oom: do not enforce OOM killer for __GFP_NOFAIL automatically mm: consolidate GFP_NOFAIL checks in the allocator slowpath lib/show_mem.c: teach show_mem to work with the given nodemask arch, mm: remove arch specific show_mem mm, page_alloc: warn_alloc print nodemask mm, page_alloc: do not report all nodes in show_mem Revert "mm: bail out in shrink_inactive_list()" mm, vmscan: consider eligible zones in get_scan_count mm, vmscan: cleanup lru size claculations mm, vmscan: do not count freed pages as PGDEACTIVATE ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/obsolete/sysfs-block-zram119
-rw-r--r--Documentation/ABI/testing/sysfs-block-zram101
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt8
-rw-r--r--Documentation/blockdev/zram.txt74
-rw-r--r--Documentation/trace/postprocess/trace-vmscan-postprocess.pl26
-rw-r--r--Documentation/vm/transhuge.txt8
6 files changed, 68 insertions, 268 deletions
diff --git a/Documentation/ABI/obsolete/sysfs-block-zram b/Documentation/ABI/obsolete/sysfs-block-zram
deleted file mode 100644
index 720ea92cfb2e..000000000000
--- a/Documentation/ABI/obsolete/sysfs-block-zram
+++ /dev/null
@@ -1,119 +0,0 @@
-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.
diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram
index 4518d30b8c2e..451b6d882b2c 100644
--- a/Documentation/ABI/testing/sysfs-block-zram
+++ b/Documentation/ABI/testing/sysfs-block-zram
@@ -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
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index d05533e6120b..986e44387dad 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3694,6 +3694,14 @@
last alloc / free. For more information see
Documentation/vm/slub.txt.
+ slub_memcg_sysfs= [MM, SLUB]
+ Determines whether to enable sysfs directories for
+ memory cgroup sub-caches. 1 to enable, 0 to disable.
+ The default is determined by CONFIG_SLUB_MEMCG_SYSFS_ON.
+ Enabling this can lead to a very high number of debug
+ directories and files being created under
+ /sys/kernel/slub.
+
slub_max_order= [MM, SLUB]
Determines the maximum allowed order for slabs.
A high setting may cause OOMs due to memory
diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt
index 0535ae1f73e5..1c0c08d9206b 100644
--- a/Documentation/blockdev/zram.txt
+++ b/Documentation/blockdev/zram.txt
@@ -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
diff --git a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
index 8f961ef2b457..ba976805853a 100644
--- a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
+++ b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
@@ -112,8 +112,8 @@ my $regex_direct_end_default = 'nr_reclaimed=([0-9]*)';
my $regex_kswapd_wake_default = 'nid=([0-9]*) order=([0-9]*)';
my $regex_kswapd_sleep_default = 'nid=([0-9]*)';
my $regex_wakeup_kswapd_default = 'nid=([0-9]*) zid=([0-9]*) order=([0-9]*)';
-my $regex_lru_isolate_default = 'isolate_mode=([0-9]*) order=([0-9]*) nr_requested=([0-9]*) nr_scanned=([0-9]*) nr_taken=([0-9]*) file=([0-9]*)';
-my $regex_lru_shrink_inactive_default = 'nid=([0-9]*) zid=([0-9]*) nr_scanned=([0-9]*) nr_reclaimed=([0-9]*) priority=([0-9]*) flags=([A-Z_|]*)';
+my $regex_lru_isolate_default = 'isolate_mode=([0-9]*) classzone_idx=([0-9]*) order=([0-9]*) nr_requested=([0-9]*) nr_scanned=([0-9]*) nr_skipped=([0-9]*) nr_taken=([0-9]*) lru=([a-z_]*)';
+my $regex_lru_shrink_inactive_default = 'nid=([0-9]*) nr_scanned=([0-9]*) nr_reclaimed=([0-9]*) nr_dirty=([0-9]*) nr_writeback=([0-9]*) nr_congested=([0-9]*) nr_immediate=([0-9]*) nr_activate=([0-9]*) nr_ref_keep=([0-9]*) nr_unmap_fail=([0-9]*) priority=([0-9]*) flags=([A-Z_|]*)';
my $regex_lru_shrink_active_default = 'lru=([A-Z_]*) nr_scanned=([0-9]*) nr_rotated=([0-9]*) priority=([0-9]*)';
my $regex_writepage_default = 'page=([0-9a-f]*) pfn=([0-9]*) flags=([A-Z_|]*)';
@@ -205,15 +205,15 @@ $regex_wakeup_kswapd = generate_traceevent_regex(
$regex_lru_isolate = generate_traceevent_regex(
"vmscan/mm_vmscan_lru_isolate",
$regex_lru_isolate_default,
- "isolate_mode", "order",
- "nr_requested", "nr_scanned", "nr_taken",
- "file");
+ "isolate_mode", "classzone_idx", "order",
+ "nr_requested", "nr_scanned", "nr_skipped", "nr_taken",
+ "lru");
$regex_lru_shrink_inactive = generate_traceevent_regex(
"vmscan/mm_vmscan_lru_shrink_inactive",
$regex_lru_shrink_inactive_default,
- "nid", "zid",
- "nr_scanned", "nr_reclaimed", "priority",
- "flags");
+ "nid", "nr_scanned", "nr_reclaimed", "nr_dirty", "nr_writeback",
+ "nr_congested", "nr_immediate", "nr_activate", "nr_ref_keep",
+ "nr_unmap_fail", "priority", "flags");
$regex_lru_shrink_active = generate_traceevent_regex(
"vmscan/mm_vmscan_lru_shrink_active",
$regex_lru_shrink_active_default,
@@ -381,8 +381,8 @@ EVENT_PROCESS:
next;
}
my $isolate_mode = $1;
- my $nr_scanned = $4;
- my $file = $6;
+ my $nr_scanned = $5;
+ my $file = $8;
# To closer match vmstat scanning statistics, only count isolate_both
# and isolate_inactive as scanning. isolate_active is rotation
@@ -391,7 +391,7 @@ EVENT_PROCESS:
# isolate_both == 3
if ($isolate_mode != 2) {
$perprocesspid{$process_pid}->{HIGH_NR_SCANNED} += $nr_scanned;
- if ($file == 1) {
+ if ($file =~ /_file/) {
$perprocesspid{$process_pid}->{HIGH_NR_FILE_SCANNED} += $nr_scanned;
} else {
$perprocesspid{$process_pid}->{HIGH_NR_ANON_SCANNED} += $nr_scanned;
@@ -406,8 +406,8 @@ EVENT_PROCESS:
next;
}
- my $nr_reclaimed = $4;
- my $flags = $6;
+ my $nr_reclaimed = $3;
+ my $flags = $12;
my $file = 0;
if ($flags =~ /RECLAIM_WB_FILE/) {
$file = 1;
diff --git a/Documentation/vm/transhuge.txt b/Documentation/vm/transhuge.txt
index f2e739545e74..cd28d5ee5273 100644
--- a/Documentation/vm/transhuge.txt
+++ b/Documentation/vm/transhuge.txt
@@ -110,6 +110,7 @@ MADV_HUGEPAGE region.
echo always >/sys/kernel/mm/transparent_hugepage/defrag
echo defer >/sys/kernel/mm/transparent_hugepage/defrag
+echo defer+madvise >/sys/kernel/mm/transparent_hugepage/defrag
echo madvise >/sys/kernel/mm/transparent_hugepage/defrag
echo never >/sys/kernel/mm/transparent_hugepage/defrag
@@ -120,10 +121,15 @@ that benefit heavily from THP use and are willing to delay the VM start
to utilise them.
"defer" means that an application will wake kswapd in the background
-to reclaim pages and wake kcompact to compact memory so that THP is
+to reclaim pages and wake kcompactd to compact memory so that THP is
available in the near future. It's the responsibility of khugepaged
to then install the THP pages later.
+"defer+madvise" will enter direct reclaim and compaction like "always", but
+only for regions that have used madvise(MADV_HUGEPAGE); all other regions
+will wake kswapd in the background to reclaim pages and wake kcompactd to
+compact memory so that THP is available in the near future.
+
"madvise" will enter direct reclaim like "always" but only for regions
that are have used madvise(MADV_HUGEPAGE). This is the default behaviour.