linux-toradex.git/include/uapi/asm-generic, branch v5.5-rc5

arch: sembuf.h: make uapi asm/sembuf.h self-contained

2019-12-05T03:44:14+00:00

Userspace cannot compile  due to some missing type
definitions.  For example, building it for x86 fails as follows:

    CC      usr/include/asm/sembuf.h.s
  In file included from :32:0:
  usr/include/asm/sembuf.h:17:20: error: field `sem_perm' has incomplete type
    struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
                      ^~~~~~~~
  usr/include/asm/sembuf.h:24:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t sem_otime; /* last semop time */
    ^~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:25:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused1;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:26:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t sem_ctime; /* last change time */
    ^~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:27:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused2;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:29:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t sem_nsems; /* no. of semaphores in array */
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:30:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused3;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:31:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused4;
    ^~~~~~~~~~~~~~~~

It is just a matter of missing include directive.

Include  to make it self-contained, and add it to
the compile-test coverage.

Link: http://lkml.kernel.org/r/20191030063855.9989-3-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arch: msgbuf.h: make uapi asm/msgbuf.h self-contained

2019-12-05T03:44:14+00:00

Userspace cannot compile  due to some missing type
definitions.  For example, building it for x86 fails as follows:

    CC      usr/include/asm/msgbuf.h.s
  In file included from usr/include/asm/msgbuf.h:6:0,
                   from :32:
  usr/include/asm-generic/msgbuf.h:25:20: error: field `msg_perm' has incomplete type
    struct ipc64_perm msg_perm;
                      ^~~~~~~~
  usr/include/asm-generic/msgbuf.h:27:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t msg_stime; /* last msgsnd time */
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:28:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t msg_rtime; /* last msgrcv time */
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:29:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t msg_ctime; /* last change time */
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:41:2: error: unknown type name `__kernel_pid_t'
    __kernel_pid_t msg_lspid; /* pid of last msgsnd */
    ^~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:42:2: error: unknown type name `__kernel_pid_t'
    __kernel_pid_t msg_lrpid; /* last receive pid */
    ^~~~~~~~~~~~~~

It is just a matter of missing include directive.

Include  to make it self-contained, and add it to
the compile-test coverage.

Link: http://lkml.kernel.org/r/20191030063855.9989-2-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arch: ipcbuf.h: make uapi asm/ipcbuf.h self-contained

2019-12-05T03:44:14+00:00

Userspace cannot compile  due to some missing type
definitions.  For example, building it for x86 fails as follows:

    CC      usr/include/asm/ipcbuf.h.s
  In file included from usr/include/asm/ipcbuf.h:1:0,
                   from :32:
  usr/include/asm-generic/ipcbuf.h:21:2: error: unknown type name `__kernel_key_t'
    __kernel_key_t  key;
    ^~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:22:2: error: unknown type name `__kernel_uid32_t'
    __kernel_uid32_t uid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:23:2: error: unknown type name `__kernel_gid32_t'
    __kernel_gid32_t gid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:24:2: error: unknown type name `__kernel_uid32_t'
    __kernel_uid32_t cuid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:25:2: error: unknown type name `__kernel_gid32_t'
    __kernel_gid32_t cgid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:26:2: error: unknown type name `__kernel_mode_t'
    __kernel_mode_t  mode;
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:28:35: error: `__kernel_mode_t' undeclared here (not in a function)
    unsigned char  __pad1[4 - sizeof(__kernel_mode_t)];
                                     ^~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:31:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused1;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:32:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused2;
    ^~~~~~~~~~~~~~~~

It is just a matter of missing include directive.

Include  to make it self-contained, and add it to
the compile-test coverage.

Link: http://lkml.kernel.org/r/20191030063855.9989-1-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

y2038: ipc: remove __kernel_time_t reference from headers

2019-11-15T13:38:28+00:00

There are two structures based on time_t that conflict between libc and
kernel: timeval and timespec. Both are now renamed to __kernel_old_timeval
and __kernel_old_timespec.

For time_t, the old typedef is still __kernel_time_t. There is nothing
wrong with that name, but it would be nice to not use that going forward
as this type is used almost only in deprecated interfaces because of
the y2038 overflow.

In the IPC headers (msgbuf.h, sembuf.h, shmbuf.h), __kernel_time_t is only
used for the 64-bit variants, which are not deprecated.

Change these to a plain 'long', which is the same type as __kernel_time_t
on all 64-bit architectures anyway, to reduce the number of users of the
old type.

Signed-off-by: Arnd Bergmann

y2038: add __kernel_old_timespec and __kernel_old_time_t

2019-11-15T13:38:27+00:00

The 'struct timespec' definition can no longer be part of the uapi headers
because it conflicts with a a now incompatible libc definition. Also,
we really want to remove it in order to prevent new uses from creeping in.

The same namespace conflict exists with time_t, which should also be
removed. __kernel_time_t could be used safely, but adding 'old' in the
name makes it clearer that this should not be used for new interfaces.

Add a replacement __kernel_old_timespec structure and __kernel_old_time_t
along the lines of __kernel_old_timeval.

Acked-by: Deepa Dinamani 
Signed-off-by: Arnd Bergmann

mm: introduce MADV_PAGEOUT

2019-09-26T00:51:41+00:00

When a process expects no accesses to a certain memory range for a long
time, it could hint kernel that the pages can be reclaimed instantly but
data should be preserved for future use.  This could reduce workingset
eviction so it ends up increasing performance.

This patch introduces the new MADV_PAGEOUT hint to madvise(2) syscall.
MADV_PAGEOUT can be used by a process to mark a memory range as not
expected to be used for a long time so that kernel reclaims *any LRU*
pages instantly.  The hint can help kernel in deciding which pages to
evict proactively.

A note: It doesn't apply SWAP_CLUSTER_MAX LRU page isolation limit
intentionally because it's automatically bounded by PMD size.  If PMD
size(e.g., 256) makes some trouble, we could fix it later by limit it to
SWAP_CLUSTER_MAX[1].

- man-page material

MADV_PAGEOUT (since Linux x.x)

Do not expect access in the near future so pages in the specified
regions could be reclaimed instantly regardless of memory pressure.
Thus, access in the range after successful operation could cause
major page fault but never lose the up-to-date contents unlike
MADV_DONTNEED. Pages belonging to a shared mapping are only processed
if a write access is allowed for the calling process.

MADV_PAGEOUT cannot be applied to locked pages, Huge TLB pages, or
VM_PFNMAP pages.

[1] https://lore.kernel.org/lkml/20190710194719.GS29695@dhcp22.suse.cz/

[minchan@kernel.org: clear PG_active on MADV_PAGEOUT]
  Link: http://lkml.kernel.org/r/20190802200643.GA181880@google.com
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-5-minchan@kernel.org
Signed-off-by: Minchan Kim 
Reported-by: kbuild test robot 
Acked-by: Michal Hocko 
Cc: James E.J. Bottomley 
Cc: Richard Henderson 
Cc: Ralf Baechle 
Cc: Chris Zankel 
Cc: Daniel Colascione 
Cc: Dave Hansen 
Cc: Hillf Danton 
Cc: Joel Fernandes (Google) 
Cc: Johannes Weiner 
Cc: Kirill A. Shutemov 
Cc: Oleksandr Natalenko 
Cc: Shakeel Butt 
Cc: Sonny Rao 
Cc: Suren Baghdasaryan 
Cc: Tim Murray 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: introduce MADV_COLD

2019-09-26T00:51:41+00:00

Patch series "Introduce MADV_COLD and MADV_PAGEOUT", v7.

- Background

The Android terminology used for forking a new process and starting an app
from scratch is a cold start, while resuming an existing app is a hot
start.  While we continually try to improve the performance of cold
starts, hot starts will always be significantly less power hungry as well
as faster so we are trying to make hot start more likely than cold start.

To increase hot start, Android userspace manages the order that apps
should be killed in a process called ActivityManagerService.
ActivityManagerService tracks every Android app or service that the user
could be interacting with at any time and translates that into a ranked
list for lmkd(low memory killer daemon).  They are likely to be killed by
lmkd if the system has to reclaim memory.  In that sense they are similar
to entries in any other cache.  Those apps are kept alive for
opportunistic performance improvements but those performance improvements
will vary based on the memory requirements of individual workloads.

- Problem

Naturally, cached apps were dominant consumers of memory on the system.
However, they were not significant consumers of swap even though they are
good candidate for swap.  Under investigation, swapping out only begins
once the low zone watermark is hit and kswapd wakes up, but the overall
allocation rate in the system might trip lmkd thresholds and cause a
cached process to be killed(we measured performance swapping out vs.
zapping the memory by killing a process.  Unsurprisingly, zapping is 10x
times faster even though we use zram which is much faster than real
storage) so kill from lmkd will often satisfy the high zone watermark,
resulting in very few pages actually being moved to swap.

- Approach

The approach we chose was to use a new interface to allow userspace to
proactively reclaim entire processes by leveraging platform information.
This allowed us to bypass the inaccuracy of the kernel’s LRUs for pages
that are known to be cold from userspace and to avoid races with lmkd by
reclaiming apps as soon as they entered the cached state.  Additionally,
it could provide many chances for platform to use much information to
optimize memory efficiency.

To achieve the goal, the patchset introduce two new options for madvise.
One is MADV_COLD which will deactivate activated pages and the other is
MADV_PAGEOUT which will reclaim private pages instantly.  These new
options complement MADV_DONTNEED and MADV_FREE by adding non-destructive
ways to gain some free memory space.  MADV_PAGEOUT is similar to
MADV_DONTNEED in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed immediately; MADV_COLD is similar
to MADV_FREE in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed when memory pressure rises.

This patch (of 5):

When a process expects no accesses to a certain memory range, it could
give a hint to kernel that the pages can be reclaimed when memory pressure
happens but data should be preserved for future use.  This could reduce
workingset eviction so it ends up increasing performance.

This patch introduces the new MADV_COLD hint to madvise(2) syscall.
MADV_COLD can be used by a process to mark a memory range as not expected
to be used in the near future.  The hint can help kernel in deciding which
pages to evict early during memory pressure.

It works for every LRU pages like MADV_[DONTNEED|FREE]. IOW, It moves

	active file page -> inactive file LRU
	active anon page -> inacdtive anon LRU

Unlike MADV_FREE, it doesn't move active anonymous pages to inactive file
LRU's head because MADV_COLD is a little bit different symantic.
MADV_FREE means it's okay to discard when the memory pressure because the
content of the page is *garbage* so freeing such pages is almost zero
overhead since we don't need to swap out and access afterward causes just
minor fault.  Thus, it would make sense to put those freeable pages in
inactive file LRU to compete other used-once pages.  It makes sense for
implmentaion point of view, too because it's not swapbacked memory any
longer until it would be re-dirtied.  Even, it could give a bonus to make
them be reclaimed on swapless system.  However, MADV_COLD doesn't mean
garbage so reclaiming them requires swap-out/in in the end so it's bigger
cost.  Since we have designed VM LRU aging based on cost-model, anonymous
cold pages would be better to position inactive anon's LRU list, not file
LRU.  Furthermore, it would help to avoid unnecessary scanning if system
doesn't have a swap device.  Let's start simpler way without adding
complexity at this moment.  However, keep in mind, too that it's a caveat
that workloads with a lot of pages cache are likely to ignore MADV_COLD on
anonymous memory because we rarely age anonymous LRU lists.

* man-page material

MADV_COLD (since Linux x.x)

Pages in the specified regions will be treated as less-recently-accessed
compared to pages in the system with similar access frequencies.  In
contrast to MADV_FREE, the contents of the region are preserved regardless
of subsequent writes to pages.

MADV_COLD cannot be applied to locked pages, Huge TLB pages, or VM_PFNMAP
pages.

[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-2-minchan@kernel.org
Signed-off-by: Minchan Kim 
Reported-by: kbuild test robot 
Acked-by: Michal Hocko 
Acked-by: Johannes Weiner 
Cc: James E.J. Bottomley 
Cc: Richard Henderson 
Cc: Ralf Baechle 
Cc: Chris Zankel 
Cc: Johannes Weiner 
Cc: Daniel Colascione 
Cc: Dave Hansen 
Cc: Hillf Danton 
Cc: Joel Fernandes (Google) 
Cc: Kirill A. Shutemov 
Cc: Oleksandr Natalenko 
Cc: Shakeel Butt 
Cc: Sonny Rao 
Cc: Suren Baghdasaryan 
Cc: Tim Murray 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ipc: fix semtimedop for generic 32-bit architectures

2019-09-06T19:49:24+00:00

As Vincent noticed, the y2038 conversion of semtimedop in linux-5.1
broke when commit 00bf25d693e7 ("y2038: use time32 syscall names on
32-bit") changed all system calls on all architectures that take
a 32-bit time_t to point to the _time32 implementation, but left out
semtimedop in the asm-generic header.

This affects all 32-bit architectures using asm-generic/unistd.h:
h8300, unicore32, openrisc, nios2, hexagon, c6x, arc, nds32 and csky.

The notable exception is riscv32, which has dropped support for the
time32 system calls entirely.

Reported-by: Vincent Chen 
Cc: stable@vger.kernel.org
Cc: Vincent Chen 
Cc: Greentime Hu 
Cc: Yoshinori Sato 
Cc: Guan Xuetao 
Cc: Stafford Horne 
Cc: Jonas Bonn 
Cc: Stefan Kristiansson 
Cc: Ley Foon Tan 
Cc: Richard Kuo 
Cc: Mark Salter 
Cc: Aurelien Jacquiot 
Cc: Guo Ren 
Fixes: 00bf25d693e7 ("y2038: use time32 syscall names on 32-bit")
Signed-off-by: Arnd Bergmann

Merge branch 'akpm' (patches from Andrew)

2019-07-17T15:58:04+00:00

Merge more updates from Andrew Morton:
 "VM:
   - z3fold fixes and enhancements by Henry Burns and Vitaly Wool

   - more accurate reclaimed slab caches calculations by Yafang Shao

   - fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by
     Christoph Hellwig

   - !CONFIG_MMU fixes by Christoph Hellwig

   - new novmcoredd parameter to omit device dumps from vmcore, by
     Kairui Song

   - new test_meminit module for testing heap and pagealloc
     initialization, by Alexander Potapenko

   - ioremap improvements for huge mappings, by Anshuman Khandual

   - generalize kprobe page fault handling, by Anshuman Khandual

   - device-dax hotplug fixes and improvements, by Pavel Tatashin

   - enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V

   - add pte_devmap() support for arm64, by Robin Murphy

   - unify locked_vm accounting with a helper, by Daniel Jordan

   - several misc fixes

  core/lib:
   - new typeof_member() macro including some users, by Alexey Dobriyan

   - make BIT() and GENMASK() available in asm, by Masahiro Yamada

   - changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better
     code generation, by Alexey Dobriyan

   - rbtree code size optimizations, by Michel Lespinasse

   - convert struct pid count to refcount_t, by Joel Fernandes

  get_maintainer.pl:
   - add --no-moderated switch to skip moderated ML's, by Joe Perches

  misc:
   - ptrace PTRACE_GET_SYSCALL_INFO interface

   - coda updates

   - gdb scripts, various"

[ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ]

* emailed patches from Andrew Morton : (100 commits)
  fs/select.c: use struct_size() in kmalloc()
  mm: add account_locked_vm utility function
  arm64: mm: implement pte_devmap support
  mm: introduce ARCH_HAS_PTE_DEVMAP
  mm: clean up is_device_*_page() definitions
  mm/mmap: move common defines to mman-common.h
  mm: move MAP_SYNC to asm-generic/mman-common.h
  device-dax: "Hotremove" persistent memory that is used like normal RAM
  mm/hotplug: make remove_memory() interface usable
  device-dax: fix memory and resource leak if hotplug fails
  include/linux/lz4.h: fix spelling and copy-paste errors in documentation
  ipc/mqueue.c: only perform resource calculation if user valid
  include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures
  scripts/gdb: add helpers to find and list devices
  scripts/gdb: add lx-genpd-summary command
  drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
  kernel/pid.c: convert struct pid count to refcount_t
  drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings
  select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining()
  select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR
  ...

mm/mmap: move common defines to mman-common.h

2019-07-17T02:23:25+00:00

Two architecture that use arch specific MMAP flags are powerpc and
sparc.  We still have few flag values common across them and other
architectures.  Consolidate this in mman-common.h.

Also update the comment to indicate where to find HugeTLB specific
reserved values

Link: http://lkml.kernel.org/r/20190604090950.31417-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V 
Reviewed-by: Andrew Morton 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds