Merge branch 'mm-everything' of git://git.kernel.org/pub/scm/linux/ke…

…rnel/git/akpm/mm

# Conflicts:
#	arch/x86/mm/Makefile

Documentation/ABI/testing/sysfs-kernel-mm-damon

@@ -40,14 +40,24 @@ Description:	Writing a number 'N' to this file creates the number of
 		directories for controlling each DAMON context named '0' to
 		'N-1' under the contexts/ directory.
 
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/avail_operations
+Date:		Apr 2022
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	Reading this file returns the available monitoring operations
+		sets on the currently running kernel.
+
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/operations
 Date:		Mar 2022
 Contact:	SeongJae Park <sj@kernel.org>
 Description:	Writing a keyword for a monitoring operations set ('vaddr' for
-		virtual address spaces monitoring, and 'paddr' for the physical
-		address space monitoring) to this file makes the context to use
-		the operations set.  Reading the file returns the keyword for
-		the operations set the context is set to use.
+		virtual address spaces monitoring, 'fvaddr' for fixed virtual
+		address ranges monitoring, and 'paddr' for the physical address
+		space monitoring) to this file makes the context to use the
+		operations set.  Reading the file returns the keyword for the
+		operations set the context is set to use.
+
+		Note that only the operations sets that listed in
+		'avail_operations' file are valid inputs.
 
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/intervals/sample_us
 Date:		Mar 2022

Documentation/admin-guide/blockdev/zram.rst

@@ -343,6 +343,11 @@ Admin can request writeback of those idle pages at right timing via::
 
 With the command, zram will writeback idle pages from memory to the storage.
 
+Additionally, if a user choose to writeback only huge and idle pages
+this can be accomplished with::
+
+        echo huge_idle > /sys/block/zramX/writeback
+
 If an admin wants to write a specific page in zram device to the backing device,
 they could write a page index into the interface.
 

Documentation/admin-guide/cgroup-v2.rst

@@ -1208,6 +1208,27 @@ PAGE_SIZE multiple when read back.
 	high limit is used and monitored properly, this limit's
 	utility is limited to providing the final safety net.
 
+  memory.reclaim
+	A write-only nested-keyed file which exists for all cgroups.
+
+	This is a simple interface to trigger memory reclaim in the
+	target cgroup.
+
+	This file accepts a single key, the number of bytes to reclaim.
+	No nested keys are currently supported.
+
+	Example::
+
+	  echo "1G" > memory.reclaim
+
+	The interface can be later extended with nested keys to
+	configure the reclaim behavior. For example, specify the
+	type of memory to reclaim from (anon, file, ..).
+
+	Please note that the kernel can over or under reclaim from
+	the target cgroup. If less bytes are reclaimed than the
+	specified amount, -EAGAIN is returned.
+
   memory.oom.group
 	A read-write single value file which exists on non-root
 	cgroups.  The default value is "0".

Documentation/admin-guide/kernel-parameters.txt

@@ -1699,7 +1699,7 @@
 			boot-time allocation of gigantic hugepages is skipped.
 
 	hugetlb_free_vmemmap=
-			[KNL] Reguires CONFIG_HUGETLB_PAGE_FREE_VMEMMAP
+			[KNL] Reguires CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
 			enabled.
 			Allows heavy hugetlb users to free up some more
 			memory (7 * PAGE_SIZE for each 2MB hugetlb page).
@@ -1708,7 +1708,7 @@
 			on:  enable the feature
 			off: disable the feature
 
-			Built with CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON=y,
+			Built with CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON=y,
 			the default is on.
 
 			This is not compatible with memory_hotplug.memmap_on_memory.

Documentation/admin-guide/mm/damon/usage.rst

@@ -68,7 +68,7 @@ comma (","). ::
     │ kdamonds/nr_kdamonds
     │ │ 0/state,pid
     │ │ │ contexts/nr_contexts
-    │ │ │ │ 0/operations
+    │ │ │ │ 0/avail_operations,operations
     │ │ │ │ │ monitoring_attrs/
     │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us
     │ │ │ │ │ │ nr_regions/min,max
@@ -143,17 +143,28 @@ be written to the file.
 contexts/<N>/
 -------------
 
-In each context directory, one file (``operations``) and three directories
-(``monitoring_attrs``, ``targets``, and ``schemes``) exist.
+In each context directory, two files (``avail_operations`` and ``operations``)
+and three directories (``monitoring_attrs``, ``targets``, and ``schemes``)
+exist.
 
 DAMON supports multiple types of monitoring operations, including those for
-virtual address space and the physical address space.  You can set and get what
-type of monitoring operations DAMON will use for the context by writing one of
-below keywords to, and reading from the file.
+virtual address space and the physical address space.  You can get the list of
+available monitoring operations set on the currently running kernel by reading
+``avail_operations`` file.  Based on the kernel configuration, the file will
+list some or all of below keywords.
 
  - vaddr: Monitor virtual address spaces of specific processes
+ - fvaddr: Monitor fixed virtual address ranges
  - paddr: Monitor the physical address space of the system
 
+Please refer to :ref:`regions sysfs directory <sysfs_regions>` for detailed
+differences between the operations sets in terms of the monitoring target
+regions.
+
+You can set and get what type of monitoring operations DAMON will use for the
+context by writing one of the keywords listed in ``avail_operations`` file and
+reading from the ``operations`` file.
+
 contexts/<N>/monitoring_attrs/
 ------------------------------
 
@@ -192,6 +203,8 @@ If you wrote ``vaddr`` to the ``contexts/<N>/operations``, each target should
 be a process.  You can specify the process to DAMON by writing the pid of the
 process to the ``pid_target`` file.
 
+.. _sysfs_regions:
+
 targets/<N>/regions
 -------------------
 
@@ -202,9 +215,10 @@ can be covered.  However, users could want to set the initial monitoring region
 to specific address ranges.
 
 In contrast, DAMON do not automatically sets and updates the monitoring target
-regions when ``paddr`` monitoring operations set is being used (``paddr`` is
-written to the ``contexts/<N>/operations``).  Therefore, users should set the
-monitoring target regions by themselves in the case.
+regions when ``fvaddr`` or ``paddr`` monitoring operations sets are being used
+(``fvaddr`` or ``paddr`` have written to the ``contexts/<N>/operations``).
+Therefore, users should set the monitoring target regions by themselves in the
+cases.
 
 For such cases, users can explicitly set the initial monitoring target regions
 as they want, by writing proper values to the files under this directory.

Documentation/admin-guide/mm/hugetlbpage.rst

@@ -164,7 +164,7 @@ default_hugepagesz
 	will all result in 256 2M huge pages being allocated.  Valid default
 	huge page size is architecture dependent.
 hugetlb_free_vmemmap
-	When CONFIG_HUGETLB_PAGE_FREE_VMEMMAP is set, this enables freeing
+	When CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is set, this enables optimizing
 	unused vmemmap pages associated with each HugeTLB page.
 
 When multiple huge page sizes are supported, ``/proc/sys/vm/nr_hugepages``

Documentation/admin-guide/mm/ksm.rst

@@ -184,6 +184,24 @@ The maximum possible ``pages_sharing/pages_shared`` ratio is limited by the
 ``max_page_sharing`` tunable. To increase the ratio ``max_page_sharing`` must
 be increased accordingly.
 
+Monitoring KSM events
+=====================
+
+There are some counters in /proc/vmstat that may be used to monitor KSM events.
+KSM might help save memory, it's a tradeoff by may suffering delay on KSM COW
+or on swapping in copy. Those events could help users evaluate whether or how
+to use KSM. For example, if cow_ksm increases too fast, user may decrease the
+range of madvise(, , MADV_MERGEABLE).
+
+cow_ksm
+	is incremented every time a KSM page triggers copy on write (COW)
+	when users try to write to a KSM page, we have to make a copy.
+
+ksm_swpin_copy
+	is incremented every time a KSM page is copied when swapping in
+	note that KSM page might be copied when swapping in because do_swap_page()
+	cannot do all the locking needed to reconstitute a cross-anon_vma KSM page.
+
 --
 Izik Eidus,
 Hugh Dickins, 17 Nov 2009

Documentation/admin-guide/sysctl/vm.rst

@@ -62,6 +62,7 @@ Currently, these files are in /proc/sys/vm:
 - overcommit_memory
 - overcommit_ratio
 - page-cluster
+- page_lock_unfairness
 - panic_on_oom
 - percpu_pagelist_high_fraction
 - stat_interval
@@ -754,6 +755,14 @@ extra faults and I/O delays for following faults if they would have been part of
 that consecutive pages readahead would have brought in.
 
 
+page_lock_unfairness
+====================
+
+This value determines the number of times that the page lock can be
+stolen from under a waiter. After the lock is stolen the number of times
+specified in this file (default is 5), the "fair lock handoff" semantics
+will apply, and the waiter will only be awakened if the lock can be taken.
+
 panic_on_oom
 ============
 

Documentation/core-api/index.rst

@@ -36,6 +36,7 @@ Library functionality that is used throughout the kernel.
    kref
    assoc_array
    xarray
+   maple_tree
    idr
    circular-buffers
    rbtree