Hi,
These pacthes begin categorizing memory management documentation. The
documents that describe userspace APIs and do not overload the reader with
implementation details can be moved to Documentation/admin-guide, so let's
do it :)
Mike Rapoport (7):
docs/vm: hugetlbpage: minor improvements
docs/vm: hugetlbpage: move section about kernel development to
hugetlbfs_reserv
docs/vm: pagemap: formatting and spelling updates
docs/vm: pagemap: change document title
docs/admin-guide: introduce basic index for mm documentation
docs/admin-guide/mm: start moving here files from Documentation/vm
docs/admin-guide/mm: convert plain text cross references to hyperlinks
Documentation/ABI/stable/sysfs-devices-node | 2 +-
.../ABI/testing/sysfs-kernel-mm-hugepages | 2 +-
Documentation/admin-guide/index.rst | 1 +
.../{vm => admin-guide/mm}/hugetlbpage.rst | 28 +++++++--------
.../{vm => admin-guide/mm}/idle_page_tracking.rst | 5 +--
Documentation/admin-guide/mm/index.rst | 28 +++++++++++++++
Documentation/{vm => admin-guide/mm}/pagemap.rst | 40 ++++++++++++----------
.../{vm => admin-guide/mm}/soft-dirty.rst | 0
.../{vm => admin-guide/mm}/userfaultfd.rst | 0
Documentation/filesystems/proc.txt | 6 ++--
Documentation/sysctl/vm.txt | 4 +--
Documentation/vm/00-INDEX | 10 ------
Documentation/vm/hugetlbfs_reserv.rst | 8 +++++
Documentation/vm/hwpoison.rst | 2 +-
Documentation/vm/index.rst | 5 ---
fs/Kconfig | 2 +-
fs/proc/task_mmu.c | 4 +--
mm/Kconfig | 5 +--
18 files changed, 89 insertions(+), 63 deletions(-)
rename Documentation/{vm => admin-guide/mm}/hugetlbpage.rst (95%)
rename Documentation/{vm => admin-guide/mm}/idle_page_tracking.rst (96%)
create mode 100644 Documentation/admin-guide/mm/index.rst
rename Documentation/{vm => admin-guide/mm}/pagemap.rst (83%)
rename Documentation/{vm => admin-guide/mm}/soft-dirty.rst (100%)
rename Documentation/{vm => admin-guide/mm}/userfaultfd.rst (100%)
--
2.7.4
Signed-off-by: Mike Rapoport <[email protected]>
---
Documentation/admin-guide/mm/hugetlbpage.rst | 3 ++-
Documentation/admin-guide/mm/idle_page_tracking.rst | 5 +++--
Documentation/admin-guide/mm/pagemap.rst | 18 +++++++++++-------
3 files changed, 16 insertions(+), 10 deletions(-)
diff --git a/Documentation/admin-guide/mm/hugetlbpage.rst b/Documentation/admin-guide/mm/hugetlbpage.rst
index 2b374d1..a8b0806 100644
--- a/Documentation/admin-guide/mm/hugetlbpage.rst
+++ b/Documentation/admin-guide/mm/hugetlbpage.rst
@@ -219,7 +219,8 @@ When adjusting the persistent hugepage count via ``nr_hugepages_mempolicy``, any
memory policy mode--bind, preferred, local or interleave--may be used. The
resulting effect on persistent huge page allocation is as follows:
-#. Regardless of mempolicy mode [see Documentation/vm/numa_memory_policy.rst],
+#. Regardless of mempolicy mode [see
+ :ref:`Documentation/vm/numa_memory_policy.rst <numa_memory_policy>`],
persistent huge pages will be distributed across the node or nodes
specified in the mempolicy as if "interleave" had been specified.
However, if a node in the policy does not contain sufficient contiguous
diff --git a/Documentation/admin-guide/mm/idle_page_tracking.rst b/Documentation/admin-guide/mm/idle_page_tracking.rst
index 92e3a25..6f7b7ca 100644
--- a/Documentation/admin-guide/mm/idle_page_tracking.rst
+++ b/Documentation/admin-guide/mm/idle_page_tracking.rst
@@ -65,8 +65,9 @@ workload one should:
are not reclaimable, he or she can filter them out using
``/proc/kpageflags``.
-See Documentation/admin-guide/mm/pagemap.rst for more information about
-``/proc/pid/pagemap``, ``/proc/kpageflags``, and ``/proc/kpagecgroup``.
+See :ref:`Documentation/admin-guide/mm/pagemap.rst <pagemap>` for more
+information about ``/proc/pid/pagemap``, ``/proc/kpageflags``, and
+``/proc/kpagecgroup``.
.. _impl_details:
diff --git a/Documentation/admin-guide/mm/pagemap.rst b/Documentation/admin-guide/mm/pagemap.rst
index 053ca64..577af85 100644
--- a/Documentation/admin-guide/mm/pagemap.rst
+++ b/Documentation/admin-guide/mm/pagemap.rst
@@ -18,7 +18,8 @@ There are four components to pagemap:
* Bits 0-54 page frame number (PFN) if present
* Bits 0-4 swap type if swapped
* Bits 5-54 swap offset if swapped
- * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
+ * Bit 55 pte is soft-dirty (see
+ :ref:`Documentation/admin-guide/mm/soft-dirty.rst <soft_dirty>`)
* Bit 56 page exclusively mapped (since 4.2)
* Bits 57-60 zero
* Bit 61 page is file-page or shared-anon (since 3.5)
@@ -97,9 +98,11 @@ Short descriptions to the page flags
A compound page with order N consists of 2^N physically contiguous pages.
A compound page with order 2 takes the form of "HTTT", where H donates its
head page and T donates its tail page(s). The major consumers of compound
- pages are hugeTLB pages (Documentation/admin-guide/mm/hugetlbpage.rst), the SLUB etc.
- memory allocators and various device drivers. However in this interface,
- only huge/giga pages are made visible to end users.
+ pages are hugeTLB pages
+ (:ref:`Documentation/admin-guide/mm/hugetlbpage.rst <hugetlbpage>`),
+ the SLUB etc. memory allocators and various device drivers.
+ However in this interface, only huge/giga pages are made visible
+ to end users.
16 - COMPOUND_TAIL
A compound page tail (see description above).
17 - HUGE
@@ -118,9 +121,10 @@ Short descriptions to the page flags
zero page for pfn_zero or huge_zero page
25 - IDLE
page has not been accessed since it was marked idle (see
- Documentation/admin-guide/mm/idle_page_tracking.rst). Note that this flag may be
- stale in case the page was accessed via a PTE. To make sure the flag
- is up-to-date one has to read ``/sys/kernel/mm/page_idle/bitmap`` first.
+ :ref:`Documentation/admin-guide/mm/idle_page_tracking.rst <idle_page_tracking>`).
+ Note that this flag may be stale in case the page was accessed via
+ a PTE. To make sure the flag is up-to-date one has to read
+ ``/sys/kernel/mm/page_idle/bitmap`` first.
IO related page flags
---------------------
--
2.7.4
Signed-off-by: Mike Rapoport <[email protected]>
---
Documentation/admin-guide/index.rst | 1 +
Documentation/admin-guide/mm/index.rst | 19 +++++++++++++++++++
2 files changed, 20 insertions(+)
create mode 100644 Documentation/admin-guide/mm/index.rst
diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst
index 5bb9161..cac906f 100644
--- a/Documentation/admin-guide/index.rst
+++ b/Documentation/admin-guide/index.rst
@@ -63,6 +63,7 @@ configure specific aspects of kernel behavior to your liking.
pm/index
thunderbolt
LSM/index
+ mm/index
.. only:: subproject and html
diff --git a/Documentation/admin-guide/mm/index.rst b/Documentation/admin-guide/mm/index.rst
new file mode 100644
index 0000000..c47c16e
--- /dev/null
+++ b/Documentation/admin-guide/mm/index.rst
@@ -0,0 +1,19 @@
+=================
+Memory Management
+=================
+
+Linux memory management subsystem is responsible, as the name implies,
+for managing the memory in the system. This includes implemnetation of
+virtual memory and demand paging, memory allocation both for kernel
+internal structures and user space programms, mapping of files into
+processes address space and many other cool things.
+
+Linux memory management is a complex system with many configurable
+settings. Most of these settings are available via ``/proc``
+filesystem and can be quired and adjusted using ``sysctl``. These APIs
+are described in Documentation/sysctl/vm.txt and in `man 5 proc`_.
+
+.. _man 5 proc: http://man7.org/linux/man-pages/man5/proc.5.html
+
+Here we document in detail how to interact with various mechanisms in
+the Linux memory management.
--
2.7.4
* fixed mistypes
* added internal cross-references for sections
Signed-off-by: Mike Rapoport <[email protected]>
---
Documentation/vm/hugetlbpage.rst | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/Documentation/vm/hugetlbpage.rst b/Documentation/vm/hugetlbpage.rst
index a5da14b..99ad5d9 100644
--- a/Documentation/vm/hugetlbpage.rst
+++ b/Documentation/vm/hugetlbpage.rst
@@ -87,7 +87,7 @@ memory pressure.
Once a number of huge pages have been pre-allocated to the kernel huge page
pool, a user with appropriate privilege can use either the mmap system call
or shared memory system calls to use the huge pages. See the discussion of
-Using Huge Pages, below.
+:ref:`Using Huge Pages <using_huge_pages>`, below.
The administrator can allocate persistent huge pages on the kernel boot
command line by specifying the "hugepages=N" parameter, where 'N' = the
@@ -115,8 +115,9 @@ over all the set of allowed nodes specified by the NUMA memory policy of the
task that modifies ``nr_hugepages``. The default for the allowed nodes--when the
task has default memory policy--is all on-line nodes with memory. Allowed
nodes with insufficient available, contiguous memory for a huge page will be
-silently skipped when allocating persistent huge pages. See the discussion
-below of the interaction of task memory policy, cpusets and per node attributes
+silently skipped when allocating persistent huge pages. See the
+:ref:`discussion below <mem_policy_and_hp_alloc>`
+of the interaction of task memory policy, cpusets and per node attributes
with the allocation and freeing of persistent huge pages.
The success or failure of huge page allocation depends on the amount of
@@ -158,7 +159,7 @@ normal page pool.
Caveat: Shrinking the persistent huge page pool via ``nr_hugepages`` such that
it becomes less than the number of huge pages in use will convert the balance
of the in-use huge pages to surplus huge pages. This will occur even if
-the number of surplus pages it would exceed the overcommit value. As long as
+the number of surplus pages would exceed the overcommit value. As long as
this condition holds--that is, until ``nr_hugepages+nr_overcommit_hugepages`` is
increased sufficiently, or the surplus huge pages go out of use and are freed--
no more surplus huge pages will be allowed to be allocated.
@@ -187,6 +188,7 @@ Inside each of these directories, the same set of files will exist::
which function as described above for the default huge page-sized case.
+.. _mem_policy_and_hp_alloc:
Interaction of Task Memory Policy with Huge Page Allocation/Freeing
===================================================================
@@ -282,6 +284,7 @@ Note that the number of overcommit and reserve pages remain global quantities,
as we don't know until fault time, when the faulting task's mempolicy is
applied, from which node the huge page allocation will be attempted.
+.. _using_huge_pages:
Using Huge Pages
================
@@ -295,7 +298,7 @@ type hugetlbfs::
min_size=<value>,nr_inodes=<value> none /mnt/huge
This command mounts a (pseudo) filesystem of type hugetlbfs on the directory
-``/mnt/huge``. Any files created on ``/mnt/huge`` uses huge pages.
+``/mnt/huge``. Any file created on ``/mnt/huge`` uses huge pages.
The ``uid`` and ``gid`` options sets the owner and group of the root of the
file system. By default the ``uid`` and ``gid`` of the current process
@@ -345,8 +348,8 @@ applications are going to use only shmat/shmget system calls or mmap with
MAP_HUGETLB. For an example of how to use mmap with MAP_HUGETLB see
:ref:`map_hugetlb <map_hugetlb>` below.
-Users who wish to use hugetlb memory via shared memory segment should be a
-member of a supplementary group and system admin needs to configure that gid
+Users who wish to use hugetlb memory via shared memory segment should be
+members of a supplementary group and system admin needs to configure that gid
into ``/proc/sys/vm/hugetlb_shm_group``. It is possible for same or different
applications to use any combination of mmaps and shm* calls, though the mount of
filesystem will be required for using mmap calls without MAP_HUGETLB.
--
2.7.4
Several documents in Documentation/vm fit quite well into the "admin/user
guide" category. The documents that don't overload the reader with lots of
implementation details and provide coherent description of certain feature
can be moved to Documentation/admin-guide/mm.
Signed-off-by: Mike Rapoport <[email protected]>
---
Documentation/ABI/stable/sysfs-devices-node | 2 +-
Documentation/ABI/testing/sysfs-kernel-mm-hugepages | 2 +-
Documentation/{vm => admin-guide/mm}/hugetlbpage.rst | 0
Documentation/{vm => admin-guide/mm}/idle_page_tracking.rst | 2 +-
Documentation/admin-guide/mm/index.rst | 9 +++++++++
Documentation/{vm => admin-guide/mm}/pagemap.rst | 6 +++---
Documentation/{vm => admin-guide/mm}/soft-dirty.rst | 0
Documentation/{vm => admin-guide/mm}/userfaultfd.rst | 0
Documentation/filesystems/proc.txt | 6 ++++--
Documentation/sysctl/vm.txt | 4 ++--
Documentation/vm/00-INDEX | 10 ----------
Documentation/vm/hwpoison.rst | 2 +-
Documentation/vm/index.rst | 5 -----
fs/Kconfig | 2 +-
fs/proc/task_mmu.c | 4 ++--
mm/Kconfig | 5 +++--
16 files changed, 28 insertions(+), 31 deletions(-)
rename Documentation/{vm => admin-guide/mm}/hugetlbpage.rst (100%)
rename Documentation/{vm => admin-guide/mm}/idle_page_tracking.rst (98%)
rename Documentation/{vm => admin-guide/mm}/pagemap.rst (96%)
rename Documentation/{vm => admin-guide/mm}/soft-dirty.rst (100%)
rename Documentation/{vm => admin-guide/mm}/userfaultfd.rst (100%)
diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node
index b38f4b7..3e90e1f 100644
--- a/Documentation/ABI/stable/sysfs-devices-node
+++ b/Documentation/ABI/stable/sysfs-devices-node
@@ -90,4 +90,4 @@ Date: December 2009
Contact: Lee Schermerhorn <[email protected]>
Description:
The node's huge page size control/query attributes.
- See Documentation/vm/hugetlbpage.rst
\ No newline at end of file
+ See Documentation/admin-guide/mm/hugetlbpage.rst
\ No newline at end of file
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-hugepages b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages
index 5140b23..fdaa216 100644
--- a/Documentation/ABI/testing/sysfs-kernel-mm-hugepages
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages
@@ -12,4 +12,4 @@ Description:
free_hugepages
surplus_hugepages
resv_hugepages
- See Documentation/vm/hugetlbpage.rst for details.
+ See Documentation/admin-guide/mm/hugetlbpage.rst for details.
diff --git a/Documentation/vm/hugetlbpage.rst b/Documentation/admin-guide/mm/hugetlbpage.rst
similarity index 100%
rename from Documentation/vm/hugetlbpage.rst
rename to Documentation/admin-guide/mm/hugetlbpage.rst
diff --git a/Documentation/vm/idle_page_tracking.rst b/Documentation/admin-guide/mm/idle_page_tracking.rst
similarity index 98%
rename from Documentation/vm/idle_page_tracking.rst
rename to Documentation/admin-guide/mm/idle_page_tracking.rst
index d1c4609..92e3a25 100644
--- a/Documentation/vm/idle_page_tracking.rst
+++ b/Documentation/admin-guide/mm/idle_page_tracking.rst
@@ -65,7 +65,7 @@ workload one should:
are not reclaimable, he or she can filter them out using
``/proc/kpageflags``.
-See Documentation/vm/pagemap.rst for more information about
+See Documentation/admin-guide/mm/pagemap.rst for more information about
``/proc/pid/pagemap``, ``/proc/kpageflags``, and ``/proc/kpagecgroup``.
.. _impl_details:
diff --git a/Documentation/admin-guide/mm/index.rst b/Documentation/admin-guide/mm/index.rst
index c47c16e..6c8b554 100644
--- a/Documentation/admin-guide/mm/index.rst
+++ b/Documentation/admin-guide/mm/index.rst
@@ -17,3 +17,12 @@ are described in Documentation/sysctl/vm.txt and in `man 5 proc`_.
Here we document in detail how to interact with various mechanisms in
the Linux memory management.
+
+.. toctree::
+ :maxdepth: 1
+
+ hugetlbpage
+ idle_page_tracking
+ pagemap
+ soft-dirty
+ userfaultfd
diff --git a/Documentation/vm/pagemap.rst b/Documentation/admin-guide/mm/pagemap.rst
similarity index 96%
rename from Documentation/vm/pagemap.rst
rename to Documentation/admin-guide/mm/pagemap.rst
index 7ba8cbd..053ca64 100644
--- a/Documentation/vm/pagemap.rst
+++ b/Documentation/admin-guide/mm/pagemap.rst
@@ -18,7 +18,7 @@ There are four components to pagemap:
* Bits 0-54 page frame number (PFN) if present
* Bits 0-4 swap type if swapped
* Bits 5-54 swap offset if swapped
- * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.rst)
+ * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
* Bit 56 page exclusively mapped (since 4.2)
* Bits 57-60 zero
* Bit 61 page is file-page or shared-anon (since 3.5)
@@ -97,7 +97,7 @@ Short descriptions to the page flags
A compound page with order N consists of 2^N physically contiguous pages.
A compound page with order 2 takes the form of "HTTT", where H donates its
head page and T donates its tail page(s). The major consumers of compound
- pages are hugeTLB pages (Documentation/vm/hugetlbpage.rst), the SLUB etc.
+ pages are hugeTLB pages (Documentation/admin-guide/mm/hugetlbpage.rst), the SLUB etc.
memory allocators and various device drivers. However in this interface,
only huge/giga pages are made visible to end users.
16 - COMPOUND_TAIL
@@ -118,7 +118,7 @@ Short descriptions to the page flags
zero page for pfn_zero or huge_zero page
25 - IDLE
page has not been accessed since it was marked idle (see
- Documentation/vm/idle_page_tracking.rst). Note that this flag may be
+ Documentation/admin-guide/mm/idle_page_tracking.rst). Note that this flag may be
stale in case the page was accessed via a PTE. To make sure the flag
is up-to-date one has to read ``/sys/kernel/mm/page_idle/bitmap`` first.
diff --git a/Documentation/vm/soft-dirty.rst b/Documentation/admin-guide/mm/soft-dirty.rst
similarity index 100%
rename from Documentation/vm/soft-dirty.rst
rename to Documentation/admin-guide/mm/soft-dirty.rst
diff --git a/Documentation/vm/userfaultfd.rst b/Documentation/admin-guide/mm/userfaultfd.rst
similarity index 100%
rename from Documentation/vm/userfaultfd.rst
rename to Documentation/admin-guide/mm/userfaultfd.rst
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 2d3984c..ef53f80 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -515,7 +515,8 @@ guarantees:
The /proc/PID/clear_refs is used to reset the PG_Referenced and ACCESSED/YOUNG
bits on both physical and virtual pages associated with a process, and the
-soft-dirty bit on pte (see Documentation/vm/soft-dirty.rst for details).
+soft-dirty bit on pte (see Documentation/admin-guide/mm/soft-dirty.rst
+for details).
To clear the bits for all the pages associated with the process
> echo 1 > /proc/PID/clear_refs
@@ -536,7 +537,8 @@ Any other value written to /proc/PID/clear_refs will have no effect.
The /proc/pid/pagemap gives the PFN, which can be used to find the pageflags
using /proc/kpageflags and number of times a page is mapped using
-/proc/kpagecount. For detailed explanation, see Documentation/vm/pagemap.rst.
+/proc/kpagecount. For detailed explanation, see
+Documentation/admin-guide/mm/pagemap.rst.
The /proc/pid/numa_maps is an extension based on maps, showing the memory
locality and binding policy, as well as the memory usage (in pages) of
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index c8e6d5b..697ef8c 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -515,7 +515,7 @@ nr_hugepages
Change the minimum size of the hugepage pool.
-See Documentation/vm/hugetlbpage.rst
+See Documentation/admin-guide/mm/hugetlbpage.rst
==============================================================
@@ -524,7 +524,7 @@ nr_overcommit_hugepages
Change the maximum size of the hugepage pool. The maximum is
nr_hugepages + nr_overcommit_hugepages.
-See Documentation/vm/hugetlbpage.rst
+See Documentation/admin-guide/mm/hugetlbpage.rst
==============================================================
diff --git a/Documentation/vm/00-INDEX b/Documentation/vm/00-INDEX
index cda564d..f8a96ca 100644
--- a/Documentation/vm/00-INDEX
+++ b/Documentation/vm/00-INDEX
@@ -12,14 +12,10 @@ highmem.rst
- Outline of highmem and common issues.
hmm.rst
- Documentation of heterogeneous memory management
-hugetlbpage.rst
- - a brief summary of hugetlbpage support in the Linux kernel.
hugetlbfs_reserv.rst
- A brief overview of hugetlbfs reservation design/implementation.
hwpoison.rst
- explains what hwpoison is
-idle_page_tracking.rst
- - description of the idle page tracking feature.
ksm.rst
- how to use the Kernel Samepage Merging feature.
mmu_notifier.rst
@@ -34,16 +30,12 @@ page_frags.rst
- description of page fragments allocator
page_migration.rst
- description of page migration in NUMA systems.
-pagemap.rst
- - pagemap, from the userspace perspective
page_owner.rst
- tracking about who allocated each page
remap_file_pages.rst
- a note about remap_file_pages() system call
slub.rst
- a short users guide for SLUB.
-soft-dirty.rst
- - short explanation for soft-dirty PTEs
split_page_table_lock.rst
- Separate per-table lock to improve scalability of the old page_table_lock.
swap_numa.rst
@@ -52,8 +44,6 @@ transhuge.rst
- Transparent Hugepage Support, alternative way of using hugepages.
unevictable-lru.rst
- Unevictable LRU infrastructure
-userfaultfd.rst
- - description of userfaultfd system call
z3fold.txt
- outline of z3fold allocator for storing compressed pages
zsmalloc.rst
diff --git a/Documentation/vm/hwpoison.rst b/Documentation/vm/hwpoison.rst
index 070aa1e..09bd24a 100644
--- a/Documentation/vm/hwpoison.rst
+++ b/Documentation/vm/hwpoison.rst
@@ -155,7 +155,7 @@ Testing
value). This allows stress testing of many kinds of
pages. The page_flags are the same as in /proc/kpageflags. The
flag bits are defined in include/linux/kernel-page-flags.h and
- documented in Documentation/vm/pagemap.rst
+ documented in Documentation/admin-guide/mm/pagemap.rst
* Architecture specific MCE injector
diff --git a/Documentation/vm/index.rst b/Documentation/vm/index.rst
index 6c45142..ed58cb9 100644
--- a/Documentation/vm/index.rst
+++ b/Documentation/vm/index.rst
@@ -13,15 +13,10 @@ various features of the Linux memory management
.. toctree::
:maxdepth: 1
- hugetlbpage
- idle_page_tracking
ksm
numa_memory_policy
- pagemap
transhuge
- soft-dirty
swap_numa
- userfaultfd
zswap
Kernel developers MM documentation
diff --git a/fs/Kconfig b/fs/Kconfig
index ba53dc2..ac4ac90 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -196,7 +196,7 @@ config HUGETLBFS
help
hugetlbfs is a filesystem backing for HugeTLB pages, based on
ramfs. For architectures that support it, say Y here and read
- <file:Documentation/vm/hugetlbpage.rst> for details.
+ <file:Documentation/admin-guide/mm/hugetlbpage.rst> for details.
If unsure, say N.
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 333cda8..ed48b6e 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -937,7 +937,7 @@ static inline void clear_soft_dirty(struct vm_area_struct *vma,
/*
* The soft-dirty tracker uses #PF-s to catch writes
* to pages, so write-protect the pte as well. See the
- * Documentation/vm/soft-dirty.rst for full description
+ * Documentation/admin-guide/mm/soft-dirty.rst for full description
* of how soft-dirty works.
*/
pte_t ptent = *pte;
@@ -1417,7 +1417,7 @@ static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
* Bits 0-54 page frame number (PFN) if present
* Bits 0-4 swap type if swapped
* Bits 5-54 swap offset if swapped
- * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.rst)
+ * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
* Bit 56 page exclusively mapped
* Bits 57-60 zero
* Bit 61 page is file-page or shared-anon
diff --git a/mm/Kconfig b/mm/Kconfig
index 9bdb018..2d7ef62 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -530,7 +530,7 @@ config MEM_SOFT_DIRTY
into a page just as regular dirty bit, but unlike the latter
it can be cleared by hands.
- See Documentation/vm/soft-dirty.rst for more details.
+ See Documentation/admin-guide/mm/soft-dirty.rst for more details.
config ZSWAP
bool "Compressed cache for swap pages (EXPERIMENTAL)"
@@ -656,7 +656,8 @@ config IDLE_PAGE_TRACKING
be useful to tune memory cgroup limits and/or for job placement
within a compute cluster.
- See Documentation/vm/idle_page_tracking.rst for more details.
+ See Documentation/admin-guide/mm/idle_page_tracking.rst for
+ more details.
# arch_add_memory() comprehends device memory
config ARCH_HAS_ZONE_DEVICE
--
2.7.4
"pagemap from the Userspace Perspective" is not very descriptive for
unaware readers. Since the document describes how to examine a process page
tables, let's title it "Examining Process Page Tables"
Signed-off-by: Mike Rapoport <[email protected]>
---
Documentation/vm/pagemap.rst | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/Documentation/vm/pagemap.rst b/Documentation/vm/pagemap.rst
index 9644bc0..7ba8cbd 100644
--- a/Documentation/vm/pagemap.rst
+++ b/Documentation/vm/pagemap.rst
@@ -1,8 +1,8 @@
.. _pagemap:
-======================================
-pagemap from the Userspace Perspective
-======================================
+=============================
+Examining Process Page Tables
+=============================
pagemap is a new (as of 2.6.25) set of interfaces in the kernel that allow
userspace programs to examine the page tables and related information by
--
2.7.4
The hugetlbpage describes hugetlbfs from the user perspective and newer
hugetlbfs_reserv document targets kernel developers. Hence the section
about hugetlbfs kernel development naturally belongs there.
Signed-off-by: Mike Rapoport <[email protected]>
---
Documentation/vm/hugetlbfs_reserv.rst | 8 ++++++++
Documentation/vm/hugetlbpage.rst | 8 --------
2 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/Documentation/vm/hugetlbfs_reserv.rst b/Documentation/vm/hugetlbfs_reserv.rst
index 36a87a2..9d20076 100644
--- a/Documentation/vm/hugetlbfs_reserv.rst
+++ b/Documentation/vm/hugetlbfs_reserv.rst
@@ -583,5 +583,13 @@ of cpusets or memory policy there is no guarantee that huge pages will be
available on the required nodes. This is true even if there are a sufficient
number of global reservations.
+Hugetlbfs regression testing
+============================
+The most complete set of hugetlb tests are in the libhugetlbfs repository.
+If you modify any hugetlb related code, use the libhugetlbfs test suite
+to check for regressions. In addition, if you add any new hugetlb
+functionality, please add appropriate tests to libhugetlbfs.
+
+--
Mike Kravetz, 7 April 2017
diff --git a/Documentation/vm/hugetlbpage.rst b/Documentation/vm/hugetlbpage.rst
index 99ad5d9..2b374d1 100644
--- a/Documentation/vm/hugetlbpage.rst
+++ b/Documentation/vm/hugetlbpage.rst
@@ -379,11 +379,3 @@ The `libhugetlbfs`_ library provides a wide range of userspace tools
to help with huge page usability, environment setup, and control.
.. _libhugetlbfs: https://github.com/libhugetlbfs/libhugetlbfs
-
-Kernel development regression testing
-=====================================
-
-The most complete set of hugetlb tests are in the libhugetlbfs repository.
-If you modify any hugetlb related code, use the libhugetlbfs test suite
-to check for regressions. In addition, if you add any new hugetlb
-functionality, please add appropriate tests to libhugetlbfs.
--
2.7.4
Signed-off-by: Mike Rapoport <[email protected]>
---
Documentation/vm/pagemap.rst | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/Documentation/vm/pagemap.rst b/Documentation/vm/pagemap.rst
index d54b4bf..9644bc0 100644
--- a/Documentation/vm/pagemap.rst
+++ b/Documentation/vm/pagemap.rst
@@ -13,7 +13,7 @@ There are four components to pagemap:
* ``/proc/pid/pagemap``. This file lets a userspace process find out which
physical frame each virtual page is mapped to. It contains one 64-bit
value for each virtual page, containing the following data (from
- fs/proc/task_mmu.c, above pagemap_read):
+ ``fs/proc/task_mmu.c``, above pagemap_read):
* Bits 0-54 page frame number (PFN) if present
* Bits 0-4 swap type if swapped
@@ -36,7 +36,7 @@ There are four components to pagemap:
precisely which pages are mapped (or in swap) and comparing mapped
pages between processes.
- Efficient users of this interface will use /proc/pid/maps to
+ Efficient users of this interface will use ``/proc/pid/maps`` to
determine which areas of memory are actually mapped and llseek to
skip over unmapped regions.
@@ -79,11 +79,11 @@ There are four components to pagemap:
memory cgroup each page is charged to, indexed by PFN. Only available when
CONFIG_MEMCG is set.
-Short descriptions to the page flags:
-=====================================
+Short descriptions to the page flags
+====================================
0 - LOCKED
- page is being locked for exclusive access, eg. by undergoing read/write IO
+ page is being locked for exclusive access, e.g. by undergoing read/write IO
7 - SLAB
page is managed by the SLAB/SLOB/SLUB/SLQB kernel memory allocator
When compound page is used, SLUB/SLQB will only set this flag on the head
@@ -132,7 +132,7 @@ IO related page flags
ie. for file backed page: (in-memory data revision >= on-disk one)
4 - DIRTY
page has been written to, hence contains new data
- ie. for file backed page: (in-memory data revision > on-disk one)
+ i.e. for file backed page: (in-memory data revision > on-disk one)
8 - WRITEBACK
page is being synced to disk
@@ -145,7 +145,7 @@ LRU related page flags
page is in the active LRU list
18 - UNEVICTABLE
page is in the unevictable (non-)LRU list It is somehow pinned and
- not a candidate for LRU page reclaims, eg. ramfs pages,
+ not a candidate for LRU page reclaims, e.g. ramfs pages,
shmctl(SHM_LOCK) and mlock() memory segments
2 - REFERENCED
page has been referenced since last LRU list enqueue/requeue
@@ -156,7 +156,7 @@ LRU related page flags
12 - ANON
a memory mapped page that is not part of a file
13 - SWAPCACHE
- page is mapped to swap space, ie. has an associated swap entry
+ page is mapped to swap space, i.e. has an associated swap entry
14 - SWAPBACKED
page is backed by swap/RAM
--
2.7.4
On Wed, 18 Apr 2018 11:07:43 +0300
Mike Rapoport <[email protected]> wrote:
> These pacthes begin categorizing memory management documentation. The
> documents that describe userspace APIs and do not overload the reader with
> implementation details can be moved to Documentation/admin-guide, so let's
> do it :)
Looks good, set applied, thanks.
jon