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Mon, 15 Dec 2025 12:08:43 -0800 (PST) Received: from localhost ([2603:7000:c01:2716:929a:4aff:fe16:c778]) by smtp.gmail.com with ESMTPSA id af79cd13be357-8be303e7e51sm25463885a.7.2025.12.15.12.08.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Dec 2025 12:08:42 -0800 (PST) Date: Mon, 15 Dec 2025 15:08:38 -0500 From: Johannes Weiner To: Christoph Hellwig Cc: Jens Axboe , Deepanshu Kartikey , akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org Subject: Re: retiring laptop_mode? was Re: [PATCH] mm: vmscan: always allow writeback during memcg reclaim Message-ID: <20251215200838.GC905277@cmpxchg.org> References: <20251213083639.364539-1-kartikey406@gmail.com> <20251215041200.GB905277@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: EA4DE1A001A X-Stat-Signature: us4pbwq3cuzkd6mfta5dehdqfqwriais X-HE-Tag: 1765829324-680457 X-HE-Meta: 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 d9ob/UMC 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun, Dec 14, 2025 at 10:59:11PM -0800, Christoph Hellwig wrote: > On Sun, Dec 14, 2025 at 11:12:00PM -0500, Johannes Weiner wrote: > > That reasoning doesn't make sense to me. Reclaim is always in response > > to an allocation need. The laptop_mode idea applies to cgroup reclaim > > as much as any other reclaim. > > > > Now obviously all of this is pretty dated. Reclaim doesn't do > > filesystem writes anymore, and I'm not sure there are a whole lot of > > laptops with rotational drives left, either. Also I doubt anybody is > > still using zone_reclaim_mode (which is where the may_unmap is from). > > Yeah. I wonder if we should retire laptop_mode. It was a cute hack > back then, but it has it's ugly fingers in way to many places and > should be mostly obsolete by how writeback works these days. Yes, that makes sense to me. How about the below? It doesn't actually get rid of the reclaim toggles - I added comments for the other usecases. But it's a nice diffstat nonetheless. Debated whether to add some sort of deprecation sysctl handler, but at least systemd-sysctl just prints a warning and still applies other settings from the same config file. --- >From 868f67e9d0d4465a6c22d8a147084944e7569c8d Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Mon, 15 Dec 2025 12:57:53 -0500 Subject: [PATCH] mm/block/fs: remove laptop_mode Laptop mode was introduced to save battery, by delaying and consolidating writes and maximize the time rotating hard drives wouldn't have to spin. Needless to say, this is a scenario of the (in)glorious past. The footprint of the feature is small, but nevertheless it's a complicating factor in mm, block, filesystems. Developers don't think about it, and the decision-making in reclaim looks dubious. It likely hasn't been tested in years while the surrounding code has evolved. Suggested-by: Christoph Hellwig Signed-off-by: Johannes Weiner --- .../admin-guide/laptops/laptop-mode.rst | 770 ------------------ Documentation/admin-guide/sysctl/vm.rst | 8 - block/blk-mq.c | 3 - fs/ext4/inode.c | 3 +- fs/sync.c | 2 - fs/xfs/xfs_super.c | 9 - include/linux/backing-dev-defs.h | 3 - include/linux/writeback.h | 4 - include/trace/events/writeback.h | 1 - include/uapi/linux/sysctl.h | 2 +- mm/backing-dev.c | 3 - mm/page-writeback.c | 66 +- mm/vmscan.c | 30 +- 13 files changed, 11 insertions(+), 893 deletions(-) delete mode 100644 Documentation/admin-guide/laptops/laptop-mode.rst diff --git a/Documentation/admin-guide/laptops/laptop-mode.rst b/Documentation/admin-guide/laptops/laptop-mode.rst deleted file mode 100644 index 66eb9cd918b5..000000000000 --- a/Documentation/admin-guide/laptops/laptop-mode.rst +++ /dev/null @@ -1,770 +0,0 @@ -=============================================== -How to conserve battery power using laptop-mode -=============================================== - -Document Author: Bart Samwel (bart@samwel.tk) - -Date created: January 2, 2004 - -Last modified: December 06, 2004 - -Introduction ------------- - -Laptop mode is used to minimize the time that the hard disk needs to be spun up, -to conserve battery power on laptops. It has been reported to cause significant -power savings. - -.. Contents - - * Introduction - * Installation - * Caveats - * The Details - * Tips & Tricks - * Control script - * ACPI integration - * Monitoring tool - - -Installation ------------- - -To use laptop mode, you don't need to set any kernel configuration options -or anything. Simply install all the files included in this document, and -laptop mode will automatically be started when you're on battery. For -your convenience, a tarball containing an installer can be downloaded at: - - http://www.samwel.tk/laptop_mode/laptop_mode/ - -To configure laptop mode, you need to edit the configuration file, which is -located in /etc/default/laptop-mode on Debian-based systems, or in -/etc/sysconfig/laptop-mode on other systems. - -Unfortunately, automatic enabling of laptop mode does not work for -laptops that don't have ACPI. On those laptops, you need to start laptop -mode manually. To start laptop mode, run "laptop_mode start", and to -stop it, run "laptop_mode stop". (Note: The laptop mode tools package now -has experimental support for APM, you might want to try that first.) - - -Caveats -------- - -* The downside of laptop mode is that you have a chance of losing up to 10 - minutes of work. If you cannot afford this, don't use it! The supplied ACPI - scripts automatically turn off laptop mode when the battery almost runs out, - so that you won't lose any data at the end of your battery life. - -* Most desktop hard drives have a very limited lifetime measured in spindown - cycles, typically about 50.000 times (it's usually listed on the spec sheet). - Check your drive's rating, and don't wear down your drive's lifetime if you - don't need to. - -* If you mount some of your ext3 filesystems with the -n option, then - the control script will not be able to remount them correctly. You must set - DO_REMOUNTS=0 in the control script, otherwise it will remount them with the - wrong options -- or it will fail because it cannot write to /etc/mtab. - -* If you have your filesystems listed as type "auto" in fstab, like I did, then - the control script will not recognize them as filesystems that need remounting. - You must list the filesystems with their true type instead. - -* It has been reported that some versions of the mutt mail client use file access - times to determine whether a folder contains new mail. If you use mutt and - experience this, you must disable the noatime remounting by setting the option - DO_REMOUNT_NOATIME to 0 in the configuration file. - - -The Details ------------ - -Laptop mode is controlled by the knob /proc/sys/vm/laptop_mode. This knob is -present for all kernels that have the laptop mode patch, regardless of any -configuration options. When the knob is set, any physical disk I/O (that might -have caused the hard disk to spin up) causes Linux to flush all dirty blocks. The -result of this is that after a disk has spun down, it will not be spun up -anymore to write dirty blocks, because those blocks had already been written -immediately after the most recent read operation. The value of the laptop_mode -knob determines the time between the occurrence of disk I/O and when the flush -is triggered. A sensible value for the knob is 5 seconds. Setting the knob to -0 disables laptop mode. - -To increase the effectiveness of the laptop_mode strategy, the laptop_mode -control script increases dirty_expire_centisecs and dirty_writeback_centisecs in -/proc/sys/vm to about 10 minutes (by default), which means that pages that are -dirtied are not forced to be written to disk as often. The control script also -changes the dirty background ratio, so that background writeback of dirty pages -is not done anymore. Combined with a higher commit value (also 10 minutes) for -ext3 filesystem (also done automatically by the control script), -this results in concentration of disk activity in a small time interval which -occurs only once every 10 minutes, or whenever the disk is forced to spin up by -a cache miss. The disk can then be spun down in the periods of inactivity. - - -Configuration -------------- - -The laptop mode configuration file is located in /etc/default/laptop-mode on -Debian-based systems, or in /etc/sysconfig/laptop-mode on other systems. It -contains the following options: - -MAX_AGE: - -Maximum time, in seconds, of hard drive spindown time that you are -comfortable with. Worst case, it's possible that you could lose this -amount of work if your battery fails while you're in laptop mode. - -MINIMUM_BATTERY_MINUTES: - -Automatically disable laptop mode if the remaining number of minutes of -battery power is less than this value. Default is 10 minutes. - -AC_HD/BATT_HD: - -The idle timeout that should be set on your hard drive when laptop mode -is active (BATT_HD) and when it is not active (AC_HD). The defaults are -20 seconds (value 4) for BATT_HD and 2 hours (value 244) for AC_HD. The -possible values are those listed in the manual page for "hdparm" for the -"-S" option. - -HD: - -The devices for which the spindown timeout should be adjusted by laptop mode. -Default is /dev/hda. If you specify multiple devices, separate them by a space. - -READAHEAD: - -Disk readahead, in 512-byte sectors, while laptop mode is active. A large -readahead can prevent disk accesses for things like executable pages (which are -loaded on demand while the application executes) and sequentially accessed data -(MP3s). - -DO_REMOUNTS: - -The control script automatically remounts any mounted journaled filesystems -with appropriate commit interval options. When this option is set to 0, this -feature is disabled. - -DO_REMOUNT_NOATIME: - -When remounting, should the filesystems be remounted with the noatime option? -Normally, this is set to "1" (enabled), but there may be programs that require -access time recording. - -DIRTY_RATIO: - -The percentage of memory that is allowed to contain "dirty" or unsaved data -before a writeback is forced, while laptop mode is active. Corresponds to -the /proc/sys/vm/dirty_ratio sysctl. - -DIRTY_BACKGROUND_RATIO: - -The percentage of memory that is allowed to contain "dirty" or unsaved data -after a forced writeback is done due to an exceeding of DIRTY_RATIO. Set -this nice and low. This corresponds to the /proc/sys/vm/dirty_background_ratio -sysctl. - -Note that the behaviour of dirty_background_ratio is quite different -when laptop mode is active and when it isn't. When laptop mode is inactive, -dirty_background_ratio is the threshold percentage at which background writeouts -start taking place. When laptop mode is active, however, background writeouts -are disabled, and the dirty_background_ratio only determines how much writeback -is done when dirty_ratio is reached. - -DO_CPU: - -Enable CPU frequency scaling when in laptop mode. (Requires CPUFreq to be setup. -See Documentation/admin-guide/pm/cpufreq.rst for more info. Disabled by default.) - -CPU_MAXFREQ: - -When on battery, what is the maximum CPU speed that the system should use? Legal -values are "slowest" for the slowest speed that your CPU is able to operate at, -or a value listed in /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies. - - -Tips & Tricks -------------- - -* Bartek Kania reports getting up to 50 minutes of extra battery life (on top - of his regular 3 to 3.5 hours) using a spindown time of 5 seconds (BATT_HD=1). - -* You can spin down the disk while playing MP3, by setting disk readahead - to 8MB (READAHEAD=16384). Effectively, the disk will read a complete MP3 at - once, and will then spin down while the MP3 is playing. (Thanks to Bartek - Kania.) - -* Drew Scott Daniels observed: "I don't know why, but when I decrease the number - of colours that my display uses it consumes less battery power. I've seen - this on powerbooks too. I hope that this is a piece of information that - might be useful to the Laptop Mode patch or its users." - -* In syslog.conf, you can prefix entries with a dash `-` to omit syncing the - file after every logging. When you're using laptop-mode and your disk doesn't - spin down, this is a likely culprit. - -* Richard Atterer observed that laptop mode does not work well with noflushd - (http://noflushd.sourceforge.net/), it seems that noflushd prevents laptop-mode - from doing its thing. - -* If you're worried about your data, you might want to consider using a USB - memory stick or something like that as a "working area". (Be aware though - that flash memory can only handle a limited number of writes, and overuse - may wear out your memory stick pretty quickly. Do _not_ use journalling - filesystems on flash memory sticks.) - - -Configuration file for control and ACPI battery scripts -------------------------------------------------------- - -This allows the tunables to be changed for the scripts via an external -configuration file - -It should be installed as /etc/default/laptop-mode on Debian, and as -/etc/sysconfig/laptop-mode on Red Hat, SUSE, Mandrake, and other work-alikes. - -Config file:: - - # Maximum time, in seconds, of hard drive spindown time that you are - # comfortable with. Worst case, it's possible that you could lose this - # amount of work if your battery fails you while in laptop mode. - #MAX_AGE=600 - - # Automatically disable laptop mode when the number of minutes of battery - # that you have left goes below this threshold. - MINIMUM_BATTERY_MINUTES=10 - - # Read-ahead, in 512-byte sectors. You can spin down the disk while playing MP3/OGG - # by setting the disk readahead to 8MB (READAHEAD=16384). Effectively, the disk - # will read a complete MP3 at once, and will then spin down while the MP3/OGG is - # playing. - #READAHEAD=4096 - - # Shall we remount journaled fs. with appropriate commit interval? (1=yes) - #DO_REMOUNTS=1 - - # And shall we add the "noatime" option to that as well? (1=yes) - #DO_REMOUNT_NOATIME=1 - - # Dirty synchronous ratio. At this percentage of dirty pages the process - # which - # calls write() does its own writeback - #DIRTY_RATIO=40 - - # - # Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been - # exceeded, the kernel will wake flusher threads which will then reduce the - # amount of dirty memory to dirty_background_ratio. Set this nice and low, - # so once some writeout has commenced, we do a lot of it. - # - #DIRTY_BACKGROUND_RATIO=5 - - # kernel default dirty buffer age - #DEF_AGE=30 - #DEF_UPDATE=5 - #DEF_DIRTY_BACKGROUND_RATIO=10 - #DEF_DIRTY_RATIO=40 - #DEF_XFS_AGE_BUFFER=15 - #DEF_XFS_SYNC_INTERVAL=30 - #DEF_XFS_BUFD_INTERVAL=1 - - # This must be adjusted manually to the value of HZ in the running kernel - # on 2.4, until the XFS people change their 2.4 external interfaces to work in - # centisecs. This can be automated, but it's a work in progress that still - # needs# some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for - # external interfaces, and that is currently always set to 100. So you don't - # need to change this on 2.6. - #XFS_HZ=100 - - # Should the maximum CPU frequency be adjusted down while on battery? - # Requires CPUFreq to be setup. - # See Documentation/admin-guide/pm/cpufreq.rst for more info - #DO_CPU=0 - - # When on battery what is the maximum CPU speed that the system should - # use? Legal values are "slowest" for the slowest speed that your - # CPU is able to operate at, or a value listed in: - # /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies - # Only applicable if DO_CPU=1. - #CPU_MAXFREQ=slowest - - # Idle timeout for your hard drive (man hdparm for valid values, -S option) - # Default is 2 hours on AC (AC_HD=244) and 20 seconds for battery (BATT_HD=4). - #AC_HD=244 - #BATT_HD=4 - - # The drives for which to adjust the idle timeout. Separate them by a space, - # e.g. HD="/dev/hda /dev/hdb". - #HD="/dev/hda" - - # Set the spindown timeout on a hard drive? - #DO_HD=1 - - -Control script --------------- - -Please note that this control script works for the Linux 2.4 and 2.6 series (thanks -to Kiko Piris). - -Control script:: - - #!/bin/bash - - # start or stop laptop_mode, best run by a power management daemon when - # ac gets connected/disconnected from a laptop - # - # install as /sbin/laptop_mode - # - # Contributors to this script: Kiko Piris - # Bart Samwel - # Micha Feigin - # Andrew Morton - # Herve Eychenne - # Dax Kelson - # - # Original Linux 2.4 version by: Jens Axboe - - ############################################################################# - - # Source config - if [ -f /etc/default/laptop-mode ] ; then - # Debian - . /etc/default/laptop-mode - elif [ -f /etc/sysconfig/laptop-mode ] ; then - # Others - . /etc/sysconfig/laptop-mode - fi - - # Don't raise an error if the config file is incomplete - # set defaults instead: - - # Maximum time, in seconds, of hard drive spindown time that you are - # comfortable with. Worst case, it's possible that you could lose this - # amount of work if your battery fails you while in laptop mode. - MAX_AGE=${MAX_AGE:-'600'} - - # Read-ahead, in kilobytes - READAHEAD=${READAHEAD:-'4096'} - - # Shall we remount journaled fs. with appropriate commit interval? (1=yes) - DO_REMOUNTS=${DO_REMOUNTS:-'1'} - - # And shall we add the "noatime" option to that as well? (1=yes) - DO_REMOUNT_NOATIME=${DO_REMOUNT_NOATIME:-'1'} - - # Shall we adjust the idle timeout on a hard drive? - DO_HD=${DO_HD:-'1'} - - # Adjust idle timeout on which hard drive? - HD="${HD:-'/dev/hda'}" - - # spindown time for HD (hdparm -S values) - AC_HD=${AC_HD:-'244'} - BATT_HD=${BATT_HD:-'4'} - - # Dirty synchronous ratio. At this percentage of dirty pages the process which - # calls write() does its own writeback - DIRTY_RATIO=${DIRTY_RATIO:-'40'} - - # cpu frequency scaling - # See Documentation/admin-guide/pm/cpufreq.rst for more info - DO_CPU=${CPU_MANAGE:-'0'} - CPU_MAXFREQ=${CPU_MAXFREQ:-'slowest'} - - # - # Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been - # exceeded, the kernel will wake flusher threads which will then reduce the - # amount of dirty memory to dirty_background_ratio. Set this nice and low, - # so once some writeout has commenced, we do a lot of it. - # - DIRTY_BACKGROUND_RATIO=${DIRTY_BACKGROUND_RATIO:-'5'} - - # kernel default dirty buffer age - DEF_AGE=${DEF_AGE:-'30'} - DEF_UPDATE=${DEF_UPDATE:-'5'} - DEF_DIRTY_BACKGROUND_RATIO=${DEF_DIRTY_BACKGROUND_RATIO:-'10'} - DEF_DIRTY_RATIO=${DEF_DIRTY_RATIO:-'40'} - DEF_XFS_AGE_BUFFER=${DEF_XFS_AGE_BUFFER:-'15'} - DEF_XFS_SYNC_INTERVAL=${DEF_XFS_SYNC_INTERVAL:-'30'} - DEF_XFS_BUFD_INTERVAL=${DEF_XFS_BUFD_INTERVAL:-'1'} - - # This must be adjusted manually to the value of HZ in the running kernel - # on 2.4, until the XFS people change their 2.4 external interfaces to work in - # centisecs. This can be automated, but it's a work in progress that still needs - # some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for external - # interfaces, and that is currently always set to 100. So you don't need to - # change this on 2.6. - XFS_HZ=${XFS_HZ:-'100'} - - ############################################################################# - - KLEVEL="$(uname -r | - { - IFS='.' read a b c - echo $a.$b - } - )" - case "$KLEVEL" in - "2.4"|"2.6") - ;; - *) - echo "Unhandled kernel version: $KLEVEL ('uname -r' = '$(uname -r)')" >&2 - exit 1 - ;; - esac - - if [ ! -e /proc/sys/vm/laptop_mode ] ; then - echo "Kernel is not patched with laptop_mode patch." >&2 - exit 1 - fi - - if [ ! -w /proc/sys/vm/laptop_mode ] ; then - echo "You do not have enough privileges to enable laptop_mode." >&2 - exit 1 - fi - - # Remove an option (the first parameter) of the form option= from - # a mount options string (the rest of the parameters). - parse_mount_opts () { - OPT="$1" - shift - echo ",$*," | sed \ - -e 's/,'"$OPT"'=[0-9]*,/,/g' \ - -e 's/,,*/,/g' \ - -e 's/^,//' \ - -e 's/,$//' - } - - # Remove an option (the first parameter) without any arguments from - # a mount option string (the rest of the parameters). - parse_nonumber_mount_opts () { - OPT="$1" - shift - echo ",$*," | sed \ - -e 's/,'"$OPT"',/,/g' \ - -e 's/,,*/,/g' \ - -e 's/^,//' \ - -e 's/,$//' - } - - # Find out the state of a yes/no option (e.g. "atime"/"noatime") in - # fstab for a given filesystem, and use this state to replace the - # value of the option in another mount options string. The device - # is the first argument, the option name the second, and the default - # value the third. The remainder is the mount options string. - # - # Example: - # parse_yesno_opts_wfstab /dev/hda1 atime atime defaults,noatime - # - # If fstab contains, say, "rw" for this filesystem, then the result - # will be "defaults,atime". - parse_yesno_opts_wfstab () { - L_DEV="$1" - OPT="$2" - DEF_OPT="$3" - shift 3 - L_OPTS="$*" - PARSEDOPTS1="$(parse_nonumber_mount_opts $OPT $L_OPTS)" - PARSEDOPTS1="$(parse_nonumber_mount_opts no$OPT $PARSEDOPTS1)" - # Watch for a default atime in fstab - FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)" - if echo "$FSTAB_OPTS" | grep "$OPT" > /dev/null ; then - # option specified in fstab: extract the value and use it - if echo "$FSTAB_OPTS" | grep "no$OPT" > /dev/null ; then - echo "$PARSEDOPTS1,no$OPT" - else - # no$OPT not found -- so we must have $OPT. - echo "$PARSEDOPTS1,$OPT" - fi - else - # option not specified in fstab -- choose the default. - echo "$PARSEDOPTS1,$DEF_OPT" - fi - } - - # Find out the state of a numbered option (e.g. "commit=NNN") in - # fstab for a given filesystem, and use this state to replace the - # value of the option in another mount options string. The device - # is the first argument, and the option name the second. The - # remainder is the mount options string in which the replacement - # must be done. - # - # Example: - # parse_mount_opts_wfstab /dev/hda1 commit defaults,commit=7 - # - # If fstab contains, say, "commit=3,rw" for this filesystem, then the - # result will be "rw,commit=3". - parse_mount_opts_wfstab () { - L_DEV="$1" - OPT="$2" - shift 2 - L_OPTS="$*" - PARSEDOPTS1="$(parse_mount_opts $OPT $L_OPTS)" - # Watch for a default commit in fstab - FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)" - if echo "$FSTAB_OPTS" | grep "$OPT=" > /dev/null ; then - # option specified in fstab: extract the value, and use it - echo -n "$PARSEDOPTS1,$OPT=" - echo ",$FSTAB_OPTS," | sed \ - -e 's/.*,'"$OPT"'=//' \ - -e 's/,.*//' - else - # option not specified in fstab: set it to 0 - echo "$PARSEDOPTS1,$OPT=0" - fi - } - - deduce_fstype () { - MP="$1" - # My root filesystem unfortunately has - # type "unknown" in /etc/mtab. If we encounter - # "unknown", we try to get the type from fstab. - cat /etc/fstab | - grep -v '^#' | - while read FSTAB_DEV FSTAB_MP FSTAB_FST FSTAB_OPTS FSTAB_DUMP FSTAB_DUMP ; do - if [ "$FSTAB_MP" = "$MP" ]; then - echo $FSTAB_FST - exit 0 - fi - done - } - - if [ $DO_REMOUNT_NOATIME -eq 1 ] ; then - NOATIME_OPT=",noatime" - fi - - case "$1" in - start) - AGE=$((100*$MAX_AGE)) - XFS_AGE=$(($XFS_HZ*$MAX_AGE)) - echo -n "Starting laptop_mode" - - if [ -d /proc/sys/vm/pagebuf ] ; then - # (For 2.4 and early 2.6.) - # This only needs to be set, not reset -- it is only used when - # laptop mode is enabled. - echo $XFS_AGE > /proc/sys/vm/pagebuf/lm_flush_age - echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval - elif [ -f /proc/sys/fs/xfs/lm_age_buffer ] ; then - # (A couple of early 2.6 laptop mode patches had these.) - # The same goes for these. - echo $XFS_AGE > /proc/sys/fs/xfs/lm_age_buffer - echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval - elif [ -f /proc/sys/fs/xfs/age_buffer ] ; then - # (2.6.6) - # But not for these -- they are also used in normal - # operation. - echo $XFS_AGE > /proc/sys/fs/xfs/age_buffer - echo $XFS_AGE > /proc/sys/fs/xfs/sync_interval - elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then - # (2.6.7 upwards) - # And not for these either. These are in centisecs, - # not USER_HZ, so we have to use $AGE, not $XFS_AGE. - echo $AGE > /proc/sys/fs/xfs/age_buffer_centisecs - echo $AGE > /proc/sys/fs/xfs/xfssyncd_centisecs - echo 3000 > /proc/sys/fs/xfs/xfsbufd_centisecs - fi - - case "$KLEVEL" in - "2.4") - echo 1 > /proc/sys/vm/laptop_mode - echo "30 500 0 0 $AGE $AGE 60 20 0" > /proc/sys/vm/bdflush - ;; - "2.6") - echo 5 > /proc/sys/vm/laptop_mode - echo "$AGE" > /proc/sys/vm/dirty_writeback_centisecs - echo "$AGE" > /proc/sys/vm/dirty_expire_centisecs - echo "$DIRTY_RATIO" > /proc/sys/vm/dirty_ratio - echo "$DIRTY_BACKGROUND_RATIO" > /proc/sys/vm/dirty_background_ratio - ;; - esac - if [ $DO_REMOUNTS -eq 1 ]; then - cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do - PARSEDOPTS="$(parse_mount_opts "$OPTS")" - if [ "$FST" = 'unknown' ]; then - FST=$(deduce_fstype $MP) - fi - case "$FST" in - "ext3") - PARSEDOPTS="$(parse_mount_opts commit "$OPTS")" - mount $DEV -t $FST $MP -o remount,$PARSEDOPTS,commit=$MAX_AGE$NOATIME_OPT - ;; - "xfs") - mount $DEV -t $FST $MP -o remount,$OPTS$NOATIME_OPT - ;; - esac - if [ -b $DEV ] ; then - blockdev --setra $(($READAHEAD * 2)) $DEV - fi - done - fi - if [ $DO_HD -eq 1 ] ; then - for THISHD in $HD ; do - /sbin/hdparm -S $BATT_HD $THISHD > /dev/null 2>&1 - /sbin/hdparm -B 1 $THISHD > /dev/null 2>&1 - done - fi - if [ $DO_CPU -eq 1 -a -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq ]; then - if [ $CPU_MAXFREQ = 'slowest' ]; then - CPU_MAXFREQ=`cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq` - fi - echo $CPU_MAXFREQ > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq - fi - echo "." - ;; - stop) - U_AGE=$((100*$DEF_UPDATE)) - B_AGE=$((100*$DEF_AGE)) - echo -n "Stopping laptop_mode" - echo 0 > /proc/sys/vm/laptop_mode - if [ -f /proc/sys/fs/xfs/age_buffer -a ! -f /proc/sys/fs/xfs/lm_age_buffer ] ; then - # These need to be restored, if there are no lm_*. - echo $(($XFS_HZ*$DEF_XFS_AGE_BUFFER)) > /proc/sys/fs/xfs/age_buffer - echo $(($XFS_HZ*$DEF_XFS_SYNC_INTERVAL)) > /proc/sys/fs/xfs/sync_interval - elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then - # These need to be restored as well. - echo $((100*$DEF_XFS_AGE_BUFFER)) > /proc/sys/fs/xfs/age_buffer_centisecs - echo $((100*$DEF_XFS_SYNC_INTERVAL)) > /proc/sys/fs/xfs/xfssyncd_centisecs - echo $((100*$DEF_XFS_BUFD_INTERVAL)) > /proc/sys/fs/xfs/xfsbufd_centisecs - fi - case "$KLEVEL" in - "2.4") - echo "30 500 0 0 $U_AGE $B_AGE 60 20 0" > /proc/sys/vm/bdflush - ;; - "2.6") - echo "$U_AGE" > /proc/sys/vm/dirty_writeback_centisecs - echo "$B_AGE" > /proc/sys/vm/dirty_expire_centisecs - echo "$DEF_DIRTY_RATIO" > /proc/sys/vm/dirty_ratio - echo "$DEF_DIRTY_BACKGROUND_RATIO" > /proc/sys/vm/dirty_background_ratio - ;; - esac - if [ $DO_REMOUNTS -eq 1 ] ; then - cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do - # Reset commit and atime options to defaults. - if [ "$FST" = 'unknown' ]; then - FST=$(deduce_fstype $MP) - fi - case "$FST" in - "ext3") - PARSEDOPTS="$(parse_mount_opts_wfstab $DEV commit $OPTS)" - PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $PARSEDOPTS)" - mount $DEV -t $FST $MP -o remount,$PARSEDOPTS - ;; - "xfs") - PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $OPTS)" - mount $DEV -t $FST $MP -o remount,$PARSEDOPTS - ;; - esac - if [ -b $DEV ] ; then - blockdev --setra 256 $DEV - fi - done - fi - if [ $DO_HD -eq 1 ] ; then - for THISHD in $HD ; do - /sbin/hdparm -S $AC_HD $THISHD > /dev/null 2>&1 - /sbin/hdparm -B 255 $THISHD > /dev/null 2>&1 - done - fi - if [ $DO_CPU -eq 1 -a -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq ]; then - echo `cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq` > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq - fi - echo "." - ;; - *) - echo "Usage: $0 {start|stop}" 2>&1 - exit 1 - ;; - - esac - - exit 0 - - -ACPI integration ----------------- - -Dax Kelson submitted this so that the ACPI acpid daemon will -kick off the laptop_mode script and run hdparm. The part that -automatically disables laptop mode when the battery is low was -written by Jan Topinski. - -/etc/acpi/events/ac_adapter:: - - event=ac_adapter - action=/etc/acpi/actions/ac.sh %e - -/etc/acpi/events/battery:: - - event=battery.* - action=/etc/acpi/actions/battery.sh %e - -/etc/acpi/actions/ac.sh:: - - #!/bin/bash - - # ac on/offline event handler - - status=`awk '/^state: / { print $2 }' /proc/acpi/ac_adapter/$2/state` - - case $status in - "on-line") - /sbin/laptop_mode stop - exit 0 - ;; - "off-line") - /sbin/laptop_mode start - exit 0 - ;; - esac - - -/etc/acpi/actions/battery.sh:: - - #! /bin/bash - - # Automatically disable laptop mode when the battery almost runs out. - - BATT_INFO=/proc/acpi/battery/$2/state - - if [[ -f /proc/sys/vm/laptop_mode ]] - then - LM=`cat /proc/sys/vm/laptop_mode` - if [[ $LM -gt 0 ]] - then - if [[ -f $BATT_INFO ]] - then - # Source the config file only now that we know we need - if [ -f /etc/default/laptop-mode ] ; then - # Debian - . /etc/default/laptop-mode - elif [ -f /etc/sysconfig/laptop-mode ] ; then - # Others - . /etc/sysconfig/laptop-mode - fi - MINIMUM_BATTERY_MINUTES=${MINIMUM_BATTERY_MINUTES:-'10'} - - ACTION="`cat $BATT_INFO | grep charging | cut -c 26-`" - if [[ ACTION -eq "discharging" ]] - then - PRESENT_RATE=`cat $BATT_INFO | grep "present rate:" | sed "s/.* \([0-9][0-9]* \).*/\1/" ` - REMAINING=`cat $BATT_INFO | grep "remaining capacity:" | sed "s/.* \([0-9][0-9]* \).*/\1/" ` - fi - if (($REMAINING * 60 / $PRESENT_RATE < $MINIMUM_BATTERY_MINUTES)) - then - /sbin/laptop_mode stop - fi - else - logger -p daemon.warning "You are using laptop mode and your battery interface $BATT_INFO is missing. This may lead to loss of data when the battery runs out. Check kernel ACPI support and /proc/acpi/battery folder, and edit /etc/acpi/battery.sh to set BATT_INFO to the correct path." - fi - fi - fi - - -Monitoring tool ---------------- - -Bartek Kania submitted this, it can be used to measure how much time your disk -spends spun up/down. See tools/laptop/dslm/dslm.c diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst index 4d71211fdad8..af14345ba94b 100644 --- a/Documentation/admin-guide/sysctl/vm.rst +++ b/Documentation/admin-guide/sysctl/vm.rst @@ -41,7 +41,6 @@ files can be found in mm/swap.c. - extfrag_threshold - highmem_is_dirtyable - hugetlb_shm_group -- laptop_mode - legacy_va_layout - lowmem_reserve_ratio - max_map_count @@ -363,13 +362,6 @@ hugetlb_shm_group contains group id that is allowed to create SysV shared memory segment using hugetlb page. -laptop_mode -=========== - -laptop_mode is a knob that controls "laptop mode". All the things that are -controlled by this knob are discussed in Documentation/admin-guide/laptops/laptop-mode.rst. - - legacy_va_layout ================ diff --git a/block/blk-mq.c b/block/blk-mq.c index 1978eef95dca..6d739bd9459d 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -811,9 +811,6 @@ void blk_mq_free_request(struct request *rq) blk_mq_finish_request(rq); - if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq))) - laptop_io_completion(q->disk->bdi); - rq_qos_done(q, rq); WRITE_ONCE(rq->state, MQ_RQ_IDLE); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 0c466ccbed69..15eb463d5a9b 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3305,8 +3305,7 @@ int ext4_alloc_da_blocks(struct inode *inode) /* * We do something simple for now. The filemap_flush() will * also start triggering a write of the data blocks, which is - * not strictly speaking necessary (and for users of - * laptop_mode, not even desirable). However, to do otherwise + * not strictly speaking necessary. However, to do otherwise * would require replicating code paths in: * * ext4_writepages() -> diff --git a/fs/sync.c b/fs/sync.c index 431fc5f5be06..6330150792f6 100644 --- a/fs/sync.c +++ b/fs/sync.c @@ -104,8 +104,6 @@ void ksys_sync(void) iterate_supers(sync_fs_one_sb, &wait); sync_bdevs(false); sync_bdevs(true); - if (unlikely(laptop_mode)) - laptop_sync_completion(); } SYSCALL_DEFINE0(sync) diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index bc71aa9dcee8..a2014fb1bc66 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -845,15 +845,6 @@ xfs_fs_sync_fs( if (error) return error; - if (laptop_mode) { - /* - * The disk must be active because we're syncing. - * We schedule log work now (now that the disk is - * active) instead of later (when it might not be). - */ - flush_delayed_work(&mp->m_log->l_work); - } - /* * If we are called with page faults frozen out, it means we are about * to freeze the transaction subsystem. Take the opportunity to shut diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h index 0217c1073735..c88fd4d37d1f 100644 --- a/include/linux/backing-dev-defs.h +++ b/include/linux/backing-dev-defs.h @@ -46,7 +46,6 @@ enum wb_reason { WB_REASON_VMSCAN, WB_REASON_SYNC, WB_REASON_PERIODIC, - WB_REASON_LAPTOP_TIMER, WB_REASON_FS_FREE_SPACE, /* * There is no bdi forker thread any more and works are done @@ -204,8 +203,6 @@ struct backing_dev_info { char dev_name[64]; struct device *owner; - struct timer_list laptop_mode_wb_timer; - #ifdef CONFIG_DEBUG_FS struct dentry *debug_dir; #endif diff --git a/include/linux/writeback.h b/include/linux/writeback.h index f48e8ccffe81..e530112c4b3a 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -328,9 +328,6 @@ struct dirty_throttle_control { bool dirty_exceeded; }; -void laptop_io_completion(struct backing_dev_info *info); -void laptop_sync_completion(void); -void laptop_mode_timer_fn(struct timer_list *t); bool node_dirty_ok(struct pglist_data *pgdat); int wb_domain_init(struct wb_domain *dom, gfp_t gfp); #ifdef CONFIG_CGROUP_WRITEBACK @@ -342,7 +339,6 @@ extern struct wb_domain global_wb_domain; /* These are exported to sysctl. */ extern unsigned int dirty_writeback_interval; extern unsigned int dirty_expire_interval; -extern int laptop_mode; void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty); unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh); diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index 311a341e6fe4..b6f94e97788a 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -42,7 +42,6 @@ EM( WB_REASON_VMSCAN, "vmscan") \ EM( WB_REASON_SYNC, "sync") \ EM( WB_REASON_PERIODIC, "periodic") \ - EM( WB_REASON_LAPTOP_TIMER, "laptop_timer") \ EM( WB_REASON_FS_FREE_SPACE, "fs_free_space") \ EM( WB_REASON_FORKER_THREAD, "forker_thread") \ EMe(WB_REASON_FOREIGN_FLUSH, "foreign_flush") diff --git a/include/uapi/linux/sysctl.h b/include/uapi/linux/sysctl.h index 63d1464cb71c..6ea9ea8413fa 100644 --- a/include/uapi/linux/sysctl.h +++ b/include/uapi/linux/sysctl.h @@ -183,7 +183,7 @@ enum VM_LOWMEM_RESERVE_RATIO=20,/* reservation ratio for lower memory zones */ VM_MIN_FREE_KBYTES=21, /* Minimum free kilobytes to maintain */ VM_MAX_MAP_COUNT=22, /* int: Maximum number of mmaps/address-space */ - VM_LAPTOP_MODE=23, /* vm laptop mode */ + VM_BLOCK_DUMP=24, /* block dump mode */ VM_HUGETLB_GROUP=25, /* permitted hugetlb group */ VM_VFS_CACHE_PRESSURE=26, /* dcache/icache reclaim pressure */ diff --git a/mm/backing-dev.c b/mm/backing-dev.c index c5740c6d37a2..a0e26d1b717f 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -1034,7 +1034,6 @@ struct backing_dev_info *bdi_alloc(int node_id) bdi->capabilities = BDI_CAP_WRITEBACK; bdi->ra_pages = VM_READAHEAD_PAGES; bdi->io_pages = VM_READAHEAD_PAGES; - timer_setup(&bdi->laptop_mode_wb_timer, laptop_mode_timer_fn, 0); return bdi; } EXPORT_SYMBOL(bdi_alloc); @@ -1156,8 +1155,6 @@ static void bdi_remove_from_list(struct backing_dev_info *bdi) void bdi_unregister(struct backing_dev_info *bdi) { - timer_delete_sync(&bdi->laptop_mode_wb_timer); - /* make sure nobody finds us on the bdi_list anymore */ bdi_remove_from_list(bdi); wb_shutdown(&bdi->wb); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index ccdeb0e84d39..0c0f048d12bb 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -109,14 +109,6 @@ EXPORT_SYMBOL_GPL(dirty_writeback_interval); */ unsigned int dirty_expire_interval = 30 * 100; /* centiseconds */ -/* - * Flag that puts the machine in "laptop mode". Doubles as a timeout in jiffies: - * a full sync is triggered after this time elapses without any disk activity. - */ -int laptop_mode; - -EXPORT_SYMBOL(laptop_mode); - /* End of sysctl-exported parameters */ struct wb_domain global_wb_domain; @@ -1843,17 +1835,7 @@ static int balance_dirty_pages(struct bdi_writeback *wb, balance_domain_limits(mdtc, strictlimit); } - /* - * In laptop mode, we wait until hitting the higher threshold - * before starting background writeout, and then write out all - * the way down to the lower threshold. So slow writers cause - * minimal disk activity. - * - * In normal mode, we start background writeout at the lower - * background_thresh, to keep the amount of dirty memory low. - */ - if (!laptop_mode && nr_dirty > gdtc->bg_thresh && - !writeback_in_progress(wb)) + if (nr_dirty > gdtc->bg_thresh && !writeback_in_progress(wb)) wb_start_background_writeback(wb); /* @@ -1876,10 +1858,6 @@ static int balance_dirty_pages(struct bdi_writeback *wb, break; } - /* Start writeback even when in laptop mode */ - if (unlikely(!writeback_in_progress(wb))) - wb_start_background_writeback(wb); - mem_cgroup_flush_foreign(wb); /* @@ -2198,41 +2176,6 @@ static int dirty_writeback_centisecs_handler(const struct ctl_table *table, int } #endif -void laptop_mode_timer_fn(struct timer_list *t) -{ - struct backing_dev_info *backing_dev_info = - timer_container_of(backing_dev_info, t, laptop_mode_wb_timer); - - wakeup_flusher_threads_bdi(backing_dev_info, WB_REASON_LAPTOP_TIMER); -} - -/* - * We've spun up the disk and we're in laptop mode: schedule writeback - * of all dirty data a few seconds from now. If the flush is already scheduled - * then push it back - the user is still using the disk. - */ -void laptop_io_completion(struct backing_dev_info *info) -{ - mod_timer(&info->laptop_mode_wb_timer, jiffies + laptop_mode); -} - -/* - * We're in laptop mode and we've just synced. The sync's writes will have - * caused another writeback to be scheduled by laptop_io_completion. - * Nothing needs to be written back anymore, so we unschedule the writeback. - */ -void laptop_sync_completion(void) -{ - struct backing_dev_info *bdi; - - rcu_read_lock(); - - list_for_each_entry_rcu(bdi, &bdi_list, bdi_list) - timer_delete(&bdi->laptop_mode_wb_timer); - - rcu_read_unlock(); -} - /* * If ratelimit_pages is too high then we can get into dirty-data overload * if a large number of processes all perform writes at the same time. @@ -2327,13 +2270,6 @@ static const struct ctl_table vm_page_writeback_sysctls[] = { .extra2 = SYSCTL_ONE, }, #endif - { - .procname = "laptop_mode", - .data = &laptop_mode, - .maxlen = sizeof(laptop_mode), - .mode = 0644, - .proc_handler = proc_dointvec_jiffies, - }, }; #endif diff --git a/mm/vmscan.c b/mm/vmscan.c index 670fe9fae5ba..a1ad50c0c9aa 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -104,13 +104,13 @@ struct scan_control { unsigned int force_deactivate:1; unsigned int skipped_deactivate:1; - /* Writepage batching in laptop mode; RECLAIM_WRITE */ + /* zone_reclaim_mode, boost reclaim */ unsigned int may_writepage:1; - /* Can mapped folios be reclaimed? */ + /* zone_reclaim_mode */ unsigned int may_unmap:1; - /* Can folios be swapped as part of reclaim? */ + /* zome_reclaim_mode, boost reclaim, cgroup restrictions */ unsigned int may_swap:1; /* Not allow cache_trim_mode to be turned on as part of reclaim? */ @@ -6366,13 +6366,6 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist, if (sc->compaction_ready) break; - - /* - * If we're getting trouble reclaiming, start doing - * writepage even in laptop mode. - */ - if (sc->priority < DEF_PRIORITY - 2) - sc->may_writepage = 1; } while (--sc->priority >= 0); last_pgdat = NULL; @@ -6581,7 +6574,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order, .order = order, .nodemask = nodemask, .priority = DEF_PRIORITY, - .may_writepage = !laptop_mode, + .may_writepage = 1, .may_unmap = 1, .may_swap = 1, }; @@ -6625,7 +6618,7 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg, struct scan_control sc = { .nr_to_reclaim = SWAP_CLUSTER_MAX, .target_mem_cgroup = memcg, - .may_writepage = !laptop_mode, + .may_writepage = 1, .may_unmap = 1, .reclaim_idx = MAX_NR_ZONES - 1, .may_swap = !noswap, @@ -6671,7 +6664,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, .reclaim_idx = MAX_NR_ZONES - 1, .target_mem_cgroup = memcg, .priority = DEF_PRIORITY, - .may_writepage = !laptop_mode, + .may_writepage = 1, .may_unmap = 1, .may_swap = !!(reclaim_options & MEMCG_RECLAIM_MAY_SWAP), .proactive = !!(reclaim_options & MEMCG_RECLAIM_PROACTIVE), @@ -7052,7 +7045,7 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx) * from reclaim context. If no pages are reclaimed, the * reclaim will be aborted. */ - sc.may_writepage = !laptop_mode && !nr_boost_reclaim; + sc.may_writepage = !nr_boost_reclaim; sc.may_swap = !nr_boost_reclaim; /* @@ -7062,13 +7055,6 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx) */ kswapd_age_node(pgdat, &sc); - /* - * If we're getting trouble reclaiming, start doing writepage - * even in laptop mode. - */ - if (sc.priority < DEF_PRIORITY - 2) - sc.may_writepage = 1; - /* Call soft limit reclaim before calling shrink_node. */ sc.nr_scanned = 0; nr_soft_scanned = 0; @@ -7789,7 +7775,7 @@ int user_proactive_reclaim(char *buf, .reclaim_idx = gfp_zone(gfp_mask), .proactive_swappiness = swappiness == -1 ? NULL : &swappiness, .priority = DEF_PRIORITY, - .may_writepage = !laptop_mode, + .may_writepage = 1, .nr_to_reclaim = max(batch_size, SWAP_CLUSTER_MAX), .may_unmap = 1, .may_swap = 1, -- 2.52.0