linux.git/arch/hexagon, branch v6.0

provide arch_test_bit_acquire for architectures that define test_bit

2022-08-27T16:49:54+00:00

Some architectures define their own arch_test_bit and they also need
arch_test_bit_acquire, otherwise they won't compile.  We also clean up
the code by using the generic test_bit if that is equivalent to the
arch-specific version.

Signed-off-by: Mikulas Patocka 
Cc: stable@vger.kernel.org
Fixes: 8238b4579866 ("wait_on_bit: add an acquire memory barrier")
Signed-off-by: Linus Torvalds

Merge tag 'bitmap-6.0-rc1' of https://github.com/norov/linux

2022-08-08T00:52:35+00:00

Pull bitmap updates from Yury Norov:

 - fix the duplicated comments on bitmap_to_arr64() (Qu Wenruo)

 - optimize out non-atomic bitops on compile-time constants (Alexander
   Lobakin)

 - cleanup bitmap-related headers (Yury Norov)

 - x86/olpc: fix 'logical not is only applied to the left hand side'
   (Alexander Lobakin)

 - lib/nodemask: inline wrappers around bitmap (Yury Norov)

* tag 'bitmap-6.0-rc1' of https://github.com/norov/linux: (26 commits)
  lib/nodemask: inline next_node_in() and node_random()
  powerpc: drop dependency on  in archrandom.h
  x86/olpc: fix 'logical not is only applied to the left hand side'
  lib/cpumask: move some one-line wrappers to header file
  headers/deps: mm: align MANITAINERS and Docs with new gfp.h structure
  headers/deps: mm: Split  out of 
  headers/deps: mm: Optimize  header dependencies
  lib/cpumask: move trivial wrappers around find_bit to the header
  lib/cpumask: change return types to unsigned where appropriate
  cpumask: change return types to bool where appropriate
  lib/bitmap: change type of bitmap_weight to unsigned long
  lib/bitmap: change return types to bool where appropriate
  arm: align find_bit declarations with generic kernel
  iommu/vt-d: avoid invalid memory access via node_online(NUMA_NO_NODE)
  lib/test_bitmap: test the tail after bitmap_to_arr64()
  lib/bitmap: fix off-by-one in bitmap_to_arr64()
  lib: test_bitmap: add compile-time optimization/evaluations assertions
  bitmap: don't assume compiler evaluates small mem*() builtins calls
  net/ice: fix initializing the bitmap in the switch code
  bitops: let optimize out non-atomic bitops on compile-time constants
  ...

Merge tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-08-07T17:03:24+00:00

Pull misc updates from Andrew Morton:
 "Updates to various subsystems which I help look after. lib, ocfs2,
  fatfs, autofs, squashfs, procfs, etc. A relatively small amount of
  material this time"

* tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  scripts/gdb: ensure the absolute path is generated on initial source
  MAINTAINERS: kunit: add David Gow as a maintainer of KUnit
  mailmap: add linux.dev alias for Brendan Higgins
  mailmap: update Kirill's email
  profile: setup_profiling_timer() is moslty not implemented
  ocfs2: fix a typo in a comment
  ocfs2: use the bitmap API to simplify code
  ocfs2: remove some useless functions
  lib/mpi: fix typo 'the the' in comment
  proc: add some (hopefully) insightful comments
  bdi: remove enum wb_congested_state
  kernel/hung_task: fix address space of proc_dohung_task_timeout_secs
  lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
  squashfs: support reading fragments in readahead call
  squashfs: implement readahead
  squashfs: always build "file direct" version of page actor
  Revert "squashfs: provide backing_dev_info in order to disable read-ahead"
  fs/ocfs2: Fix spelling typo in comment
  ia64: old_rr4 added under CONFIG_HUGETLB_PAGE
  proc: fix test for "vsyscall=xonly" boot option
  ...

profile: setup_profiling_timer() is moslty not implemented

2022-07-30T01:12:36+00:00

The setup_profiling_timer() is mostly un-implemented by many
architectures.  In many places it isn't guarded by CONFIG_PROFILE which is
needed for it to be used.  Make it a weak symbol in kernel/profile.c and
remove the 'return -EINVAL' implementations from the kenrel.

There are a couple of architectures which do return 0 from the
setup_profiling_timer() function but they don't seem to do anything else
with it.  To keep the /proc compatibility for now, leave these for a
future update or removal.

On ARM, this fixes the following sparse warning:
arch/arm/kernel/smp.c:793:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static?

Link: https://lkml.kernel.org/r/20220721195509.418205-1-ben-linux@fluff.org
Signed-off-by: Ben Dooks 
Signed-off-by: Andrew Morton

mm/mmap: drop ARCH_HAS_VM_GET_PAGE_PROT

2022-07-18T00:14:41+00:00

Now all the platforms enable ARCH_HAS_GET_PAGE_PROT.  They define and
export own vm_get_page_prot() whether custom or standard
DECLARE_VM_GET_PAGE_PROT.  Hence there is no need for default generic
fallback for vm_get_page_prot().  Just drop this fallback and also
ARCH_HAS_GET_PAGE_PROT mechanism.

Link: https://lkml.kernel.org/r/20220711070600.2378316-27-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual 
Reviewed-by: Geert Uytterhoeven 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Christophe Leroy 
Acked-by: Geert Uytterhoeven 
Cc: Arnd Bergmann 
Cc: Brian Cain 
Cc: Catalin Marinas 
Cc: Christoph Hellwig 
Cc: Chris Zankel 
Cc: "David S. Miller" 
Cc: Dinh Nguyen 
Cc: Guo Ren 
Cc: Heiko Carstens 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: "James E.J. Bottomley" 
Cc: Jeff Dike 
Cc: Jonas Bonn 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Nicholas Piggin 
Cc: Palmer Dabbelt 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Richard Henderson 
Cc: Rich Felker 
Cc: Russell King 
Cc: Sam Ravnborg 
Cc: Stafford Horne 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: WANG Xuerui 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

hexagon/mm: enable ARCH_HAS_VM_GET_PAGE_PROT

2022-07-18T00:14:39+00:00

This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports
standard vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT,
which looks up a private and static protection_map[] array.  Subsequently
all __SXXX and __PXXX macros can be dropped which are no longer needed.

Link: https://lkml.kernel.org/r/20220711070600.2378316-13-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual 
Acked-by: Brian Cain 
Cc: Arnd Bergmann 
Cc: Catalin Marinas 
Cc: Christophe Leroy 
Cc: Christoph Hellwig 
Cc: Christoph Hellwig 
Cc: Chris Zankel 
Cc: "David S. Miller" 
Cc: Dinh Nguyen 
Cc: Geert Uytterhoeven 
Cc: Guo Ren 
Cc: Heiko Carstens 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: "James E.J. Bottomley" 
Cc: Jeff Dike 
Cc: Jonas Bonn 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Nicholas Piggin 
Cc: Palmer Dabbelt 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Richard Henderson 
Cc: Rich Felker 
Cc: Russell King 
Cc: Sam Ravnborg 
Cc: Stafford Horne 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: WANG Xuerui 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

bitops: unify non-atomic bitops prototypes across architectures

2022-07-01T02:52:41+00:00

Currently, there is a mess with the prototypes of the non-atomic
bitops across the different architectures:

ret	bool, int, unsigned long
nr	int, long, unsigned int, unsigned long
addr	volatile unsigned long *, volatile void *

Thankfully, it doesn't provoke any bugs, but can sometimes make
the compiler angry when it's not handy at all.
Adjust all the prototypes to the following standard:

ret	bool				retval can be only 0 or 1
nr	unsigned long			native; signed makes no sense
addr	volatile unsigned long *	bitmaps are arrays of ulongs

Next, some architectures don't define 'arch_' versions as they don't
support instrumentation, others do. To make sure there is always the
same set of callables present and to ease any potential future
changes, make them all follow the rule:
 * architecture-specific files define only 'arch_' versions;
 * non-prefixed versions can be defined only in asm-generic files;
and place the non-prefixed definitions into a new file in
asm-generic to be included by non-instrumented architectures.

Finally, add some static assertions in order to prevent people from
making a mess in this room again.
I also used the %__always_inline attribute consistently, so that
they always get resolved to the actual operations.

Suggested-by: Andy Shevchenko 
Signed-off-by: Alexander Lobakin 
Acked-by: Mark Rutland 
Reviewed-by: Yury Norov 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Yury Norov

mm: avoid unnecessary page fault retires on shared memory types

2022-06-17T02:48:27+00:00

I observed that for each of the shared file-backed page faults, we're very
likely to retry one more time for the 1st write fault upon no page.  It's
because we'll need to release the mmap lock for dirty rate limit purpose
with balance_dirty_pages_ratelimited() (in fault_dirty_shared_page()).

Then after that throttling we return VM_FAULT_RETRY.

We did that probably because VM_FAULT_RETRY is the only way we can return
to the fault handler at that time telling it we've released the mmap lock.

However that's not ideal because it's very likely the fault does not need
to be retried at all since the pgtable was well installed before the
throttling, so the next continuous fault (including taking mmap read lock,
walk the pgtable, etc.) could be in most cases unnecessary.

It's not only slowing down page faults for shared file-backed, but also add
more mmap lock contention which is in most cases not needed at all.

To observe this, one could try to write to some shmem page and look at
"pgfault" value in /proc/vmstat, then we should expect 2 counts for each
shmem write simply because we retried, and vm event "pgfault" will capture
that.

To make it more efficient, add a new VM_FAULT_COMPLETED return code just to
show that we've completed the whole fault and released the lock.  It's also
a hint that we should very possibly not need another fault immediately on
this page because we've just completed it.

This patch provides a ~12% perf boost on my aarch64 test VM with a simple
program sequentially dirtying 400MB shmem file being mmap()ed and these are
the time it needs:

  Before: 650.980 ms (+-1.94%)
  After:  569.396 ms (+-1.38%)

I believe it could help more than that.

We need some special care on GUP and the s390 pgfault handler (for gmap
code before returning from pgfault), the rest changes in the page fault
handlers should be relatively straightforward.

Another thing to mention is that mm_account_fault() does take this new
fault as a generic fault to be accounted, unlike VM_FAULT_RETRY.

I explicitly didn't touch hmm_vma_fault() and break_ksm() because they do
not handle VM_FAULT_RETRY even with existing code, so I'm literally keeping
them as-is.

Link: https://lkml.kernel.org/r/20220530183450.42886-1-peterx@redhat.com
Signed-off-by: Peter Xu 
Acked-by: Geert Uytterhoeven 
Acked-by: Peter Zijlstra (Intel) 
Acked-by: Johannes Weiner 
Acked-by: Vineet Gupta 
Acked-by: Guo Ren 
Acked-by: Max Filippov 
Acked-by: Christian Borntraeger 
Acked-by: Michael Ellerman  (powerpc)
Acked-by: Catalin Marinas 
Reviewed-by: Alistair Popple 
Reviewed-by: Ingo Molnar 
Acked-by: Russell King (Oracle) 	[arm part]
Acked-by: Heiko Carstens 
Cc: Vasily Gorbik 
Cc: Stafford Horne 
Cc: David S. Miller 
Cc: Johannes Berg 
Cc: Brian Cain 
Cc: Richard Henderson 
Cc: Richard Weinberger 
Cc: Benjamin Herrenschmidt 
Cc: Thomas Gleixner 
Cc: Janosch Frank 
Cc: Albert Ou 
Cc: Anton Ivanov 
Cc: Dave Hansen 
Cc: Borislav Petkov 
Cc: Sven Schnelle 
Cc: Andrea Arcangeli 
Cc: James Bottomley 
Cc: Al Viro 
Cc: Alexander Gordeev 
Cc: Jonas Bonn 
Cc: Will Deacon 
Cc: Vlastimil Babka 
Cc: Michal Simek 
Cc: Matt Turner 
Cc: Paul Mackerras 
Cc: David Hildenbrand 
Cc: Nicholas Piggin 
Cc: Palmer Dabbelt 
Cc: Stefan Kristiansson 
Cc: Paul Walmsley 
Cc: Ivan Kokshaysky 
Cc: Chris Zankel 
Cc: Hugh Dickins 
Cc: Dinh Nguyen 
Cc: Rich Felker 
Cc: H. Peter Anvin 
Cc: Andy Lutomirski 
Cc: Thomas Bogendoerfer 
Cc: Helge Deller 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

fork: Generalize PF_IO_WORKER handling

2022-05-07T14:01:59+00:00

Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any task that wants to be a user space task that only runs
in kernel mode to use this functionality.

The code on x86 is an exception and still retains a PF_KTHREAD test
because x86 unlikely everything else handles kthreads slightly
differently than user space tasks that start with a function.

The functions that created tasks that start with a function
have been updated to set ".fn" and ".fn_arg" instead of
".stack" and ".stack_size".  These functions are fork_idle(),
create_io_thread(), kernel_thread(), and user_mode_thread().

Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman"

fork: Pass struct kernel_clone_args into copy_thread

2022-05-07T14:01:48+00:00

With io_uring we have started supporting tasks that are for most
purposes user space tasks that exclusively run code in kernel mode.

The kernel task that exec's init and tasks that exec user mode
helpers are also user mode tasks that just run kernel code
until they call kernel execve.

Pass kernel_clone_args into copy_thread so these oddball
tasks can be supported more cleanly and easily.

v2: Fix spelling of kenrel_clone_args on h8300
Link: https://lkml.kernel.org/r/20220506141512.516114-2-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman"