mm: introduce ctor/dtor at PGD level

Following on from the introduction of P4D-level ctor/dtor, let's finish
the job and introduce ctor/dtor at PGD level. The incurred improvement in
page accountin

mm: introduce ctor/dtor at PGD level

Following on from the introduction of P4D-level ctor/dtor, let's finish
the job and introduce ctor/dtor at PGD level. The incurred improvement in
page accounting is minimal - the main motivation is to create a single,
generic place where construction/destruction hooks can be added for all
page table pages.

This patch should cover all architectures and all configurations where
PGDs are one or more regular pages. This excludes any configuration where
PGDs are allocated from a kmem_cache object.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Kevin Brodsky <[email protected]>
Acked-by: Dave Hansen <[email protected]>
Acked-by: Qi Zheng <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Linus Walleij <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

asm-generic: pgalloc: provide generic __pgd_{alloc,free}

We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free(). Let's finish the work and add a generic PGD-l

asm-generic: pgalloc: provide generic __pgd_{alloc,free}

We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free(). Let's finish the work and add a generic PGD-level
alloc helper as well.

Unlike at lower levels, almost all architectures need some specific magic
at PGD level (typically initialising PGD entries), so introducing a
generic pgd_alloc() isn't worth it. Instead we introduce two new helpers,
__pgd_alloc() and __pgd_free(), and make use of them in the arch-specific
pgd_alloc() and pgd_free() wherever possible. To accommodate as many arch
as possible, __pgd_alloc() takes a page allocation order.

Because pagetable_alloc() allocates zeroed pages, explicit zeroing in
pgd_alloc() becomes redundant and we can get rid of it. Some trivial
implementations of pgd_free() also become unnecessary once __pgd_alloc()
is used; remove them.

Another small improvement is consistent accounting of PGD pages by using
GFP_PGTABLE_{USER,KERNEL} as appropriate.

Not all PGD allocations can be handled by the generic helpers. In
particular, multiple architectures allocate PGDs from a kmem_cache, and
those PGDs may not be page-sized.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Kevin Brodsky <[email protected]>
Acked-by: Dave Hansen <[email protected]>
Acked-by: Qi Zheng <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Linus Walleij <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

mm: pgtable: introduce generic pagetable_dtor_free()

The pte_free(), pmd_free(), __pud_free() and __p4d_free() in
asm-generic/pgalloc.h and the generic __tlb_remove_table() are basically
the same, s

mm: pgtable: introduce generic pagetable_dtor_free()

The pte_free(), pmd_free(), __pud_free() and __p4d_free() in
asm-generic/pgalloc.h and the generic __tlb_remove_table() are basically
the same, so let's introduce pagetable_dtor_free() to deduplicate them.

In addition, the pagetable_dtor_free() in s390 does the same thing, so
let's s390 also calls generic pagetable_dtor_free().

Link: https://lkml.kernel.org/r/1663a0565aca881d1338ceb7d1db4aa9c333abd6.1736317725.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <[email protected]>
Suggested-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Kevin Brodsky <[email protected]>
Acked-by: Alexander Gordeev <[email protected]> [s390]
Cc: Alexandre Ghiti <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Andreas Larsson <[email protected]>
Cc: Aneesh Kumar K.V (Arm) <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vishal Moola (Oracle) <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

mm: pgtable: introduce pagetable_dtor()

The pagetable_p*_dtor() are exactly the same except for the handling of
ptlock. If we make ptlock_free() handle the case where ptdesc->ptl is
NULL and remove

mm: pgtable: introduce pagetable_dtor()

The pagetable_p*_dtor() are exactly the same except for the handling of
ptlock. If we make ptlock_free() handle the case where ptdesc->ptl is
NULL and remove VM_BUG_ON_PAGE() from pmd_ptlock_free(), we can unify
pagetable_p*_dtor() into one function. Let's introduce pagetable_dtor()
to do this.

Later, pagetable_dtor() will be moved to tlb_remove_ptdesc(), so that
ptlock and page table pages can be freed together (regardless of whether
RCU is used). This prevents the use-after-free problem where the ptlock
is freed immediately but the page table pages is freed later via RCU.

Link: https://lkml.kernel.org/r/47f44fff9dc68d9d9e9a0d6c036df275f820598a.1736317725.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <[email protected]>
Originally-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Kevin Brodsky <[email protected]>
Acked-by: Alexander Gordeev <[email protected]> [s390]
Cc: Alexandre Ghiti <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Andreas Larsson <[email protected]>
Cc: Aneesh Kumar K.V (Arm) <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vishal Moola (Oracle) <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

mm: pgtable: add statistics for P4D level page table

Like other levels of page tables, add statistics for P4D level page table.

Link: https://lkml.kernel.org/r/d55fe3c286305aae84457da9e1066df99b3de

mm: pgtable: add statistics for P4D level page table

Like other levels of page tables, add statistics for P4D level page table.

Link: https://lkml.kernel.org/r/d55fe3c286305aae84457da9e1066df99b3de125.1736317725.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <[email protected]>
Originally-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Kevin Brodsky <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Andreas Larsson <[email protected]>
Cc: Aneesh Kumar K.V (Arm) <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vishal Moola (Oracle) <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

asm-generic: pgalloc: provide generic p4d_{alloc_one,free}

Four architectures currently implement 5-level pgtables: arm64, riscv, x86
and s390. The first three have essentially the same implementat

asm-generic: pgalloc: provide generic p4d_{alloc_one,free}

Four architectures currently implement 5-level pgtables: arm64, riscv, x86
and s390. The first three have essentially the same implementation for
p4d_alloc_one() and p4d_free(), so we've got an opportunity to reduce
duplication like at the lower levels.

Provide a generic version of p4d_alloc_one() and p4d_free(), and make use
of it on those architectures.

Their implementation is the same as at PUD level, except that p4d_free()
performs a runtime check by calling mm_p4d_folded(). 5-level pgtables
depend on a runtime-detected hardware feature on all supported
architectures, so we might as well include this check in the generic
implementation. No runtime check is required in p4d_alloc_one() as the
top-level p4d_alloc() already does the required check.

Link: https://lkml.kernel.org/r/26d69c74a29183ecc335b9b407040d8e4cd70c6a.1736317725.git.zhengqi.arch@bytedance.com
Signed-off-by: Kevin Brodsky <[email protected]>
Signed-off-by: Qi Zheng <[email protected]>
Acked-by: Dave Hansen <[email protected]>
Acked-by: Arnd Bergmann <[email protected]> [asm-generic]
Cc: Alexander Gordeev <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Andreas Larsson <[email protected]>
Cc: Aneesh Kumar K.V (Arm) <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vishal Moola (Oracle) <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

mm: change inlined allocation helpers to account at the call site

Main goal of memory allocation profiling patchset is to provide accounting
that is cheap enough to run in production. To achieve th

mm: change inlined allocation helpers to account at the call site

Main goal of memory allocation profiling patchset is to provide accounting
that is cheap enough to run in production. To achieve that we inject
counters using codetags at the allocation call sites to account every time
allocation is made. This injection allows us to perform accounting
efficiently because injected counters are immediately available as opposed
to the alternative methods, such as using _RET_IP_, which would require
counter lookup and appropriate locking that makes accounting much more
expensive. This method requires all allocation functions to inject
separate counters at their call sites so that their callers can be
individually accounted. Counter injection is implemented by allocation
hooks which should wrap all allocation functions.

Inlined functions which perform allocations but do not use allocation
hooks are directly charged for the allocations they perform. In most
cases these functions are just specialized allocation wrappers used from
multiple places to allocate objects of a specific type. It would be more
useful to do the accounting at their call sites instead. Instrument these
helpers to do accounting at the call site. Simple inlined allocation
wrappers are converted directly into macros. More complex allocators or
allocators with documentation are converted into _noprof versions and
allocation hooks are added. This allows memory allocation profiling
mechanism to charge allocations to the callers of these functions.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghdasaryan <[email protected]>
Acked-by: Jan Kara <[email protected]> [jbd2]
Cc: Anna Schumaker <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Benjamin Tissoires <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Jakub Sitnicki <[email protected]>
Cc: Jiri Kosina <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Paolo Abeni <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Theodore Ts'o <[email protected]>
Cc: Trond Myklebust <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

mm: add statistics for PUD level pagetable

Recently, we found that cross-die access to pagetable pages on ARM64
machines can cause performance fluctuations in our business. Currently,
there are no

mm: add statistics for PUD level pagetable

Recently, we found that cross-die access to pagetable pages on ARM64
machines can cause performance fluctuations in our business. Currently,
there are no PMU events available to track this situation on our ARM64
machines, so accurate pagetable accounting can help to analyze this issue,
but now the PUD level pagetable accounting is missed.

So introduce pagetable_pud_ctor/dtor() to help to get accurate PUD
pagetable accounting, as well as converting the architectures which use
generic PUD pagetable allocation to add corresponding PUD pagetable
accounting. Moreover this patch will mark the PUD level pagetable with
PG_table flag, which will help to do sanity validation in
unpoison_memory().

On my testing machine, I can see more pagetables statistics after the patch
with page-types tool:

Before patch:
flags page-count MB symbolic-flags long-symbolic-flags
0x0000000004000000 27326 106 __________________________g_________________ pgtable
After patch:
0x0000000004000000 27541 107 __________________________g_________________ pgtable

Link: https://lkml.kernel.org/r/876c71c03a7e69c17722a690e3225a4f7b172fb2.1695017383.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <[email protected]>
Acked-by: Mike Rapoport (IBM) <[email protected]>
Acked-by: Vishal Moola (Oracle) <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

pgalloc: convert various functions to use ptdescs

As part of the conversions to replace pgtable constructor/destructors with
ptdesc equivalents, convert various page table functions to use ptdescs.

pgalloc: convert various functions to use ptdescs

As part of the conversions to replace pgtable constructor/destructors with
ptdesc equivalents, convert various page table functions to use ptdescs.

Some of the functions use the *get*page*() helper functions. Convert
these to use pagetable_alloc() and ptdesc_address() instead to help
standardize page tables further.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Vishal Moola (Oracle) <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Claudio Imbrenda <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Dinh Nguyen <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: John Paul Adrian Glaubitz <[email protected]>
Cc: Jonas Bonn <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Mike Rapoport (IBM) <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

mm: prefer xxx_page() alloc/free functions for order-0 pages

Update instances of alloc_pages(..., 0), __get_free_pages(..., 0) and
__free_pages(..., 0) to use alloc_page(), __get_free_page() and
__f

mm: prefer xxx_page() alloc/free functions for order-0 pages

Update instances of alloc_pages(..., 0), __get_free_pages(..., 0) and
__free_pages(..., 0) to use alloc_page(), __get_free_page() and
__free_page() respectively in core code.

Link: https://lkml.kernel.org/r/50c48ca4789f1da2a65795f2346f5ae3eff7d665.1678710232.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Reviewed-by: Mike Rapoport (IBM) <[email protected]>
Acked-by: Mel Gorman <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Uladzislau Rezki (Sony) <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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asm-generic: Prepare for riscv use of pud_alloc_one and pud_free

In the following commits, riscv will almost use the generic versions of
pud_alloc_one and pud_free but an additional check is require

asm-generic: Prepare for riscv use of pud_alloc_one and pud_free

In the following commits, riscv will almost use the generic versions of
pud_alloc_one and pud_free but an additional check is required since those
functions are only relevant when using at least a 4-level page table, which
will be determined at runtime on riscv.

So move the content of those functions into other functions that riscv
can use without duplicating code.

Signed-off-by: Alexandre Ghiti <[email protected]>
Signed-off-by: Palmer Dabbelt <[email protected]>

show more ...

asm-generic: pgalloc.h: use correct #ifdef to enable pud_alloc_one()

The #ifdef statement that guards the generic version of pud_alloc_one() by
mistake used __HAVE_ARCH_PUD_FREE instead of __HAVE_AR

asm-generic: pgalloc.h: use correct #ifdef to enable pud_alloc_one()

The #ifdef statement that guards the generic version of pud_alloc_one() by
mistake used __HAVE_ARCH_PUD_FREE instead of __HAVE_ARCH_PUD_ALLOC_ONE.

Fix it.

Fixes: d9e8b929670b ("asm-generic: pgalloc: provide generic pud_alloc_one() and pud_free_one()")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

asm-generic: pgalloc: provide generic pgd_free()

Most architectures define pgd_free() as a wrapper for free_page().

Provide a generic version in asm-generic/pgalloc.h and enable its use for
most ar

asm-generic: pgalloc: provide generic pgd_free()

Most architectures define pgd_free() as a wrapper for free_page().

Provide a generic version in asm-generic/pgalloc.h and enable its use for
most architectures.

Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Pekka Enberg <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> [m68k]
Cc: Abdul Haleem <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Cc: Satheesh Rajendran <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

asm-generic: pgalloc: provide generic pud_alloc_one() and pud_free_one()

Several architectures define pud_alloc_one() as a wrapper for
__get_free_page() and pud_free() as a wrapper for free_page().

asm-generic: pgalloc: provide generic pud_alloc_one() and pud_free_one()

Several architectures define pud_alloc_one() as a wrapper for
__get_free_page() and pud_free() as a wrapper for free_page().

Provide a generic implementation in asm-generic/pgalloc.h and use it where
appropriate.

Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Pekka Enberg <[email protected]>
Cc: Abdul Haleem <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Cc: Satheesh Rajendran <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

asm-generic: pgalloc: provide generic pmd_alloc_one() and pmd_free_one()

For most architectures that support >2 levels of page tables,
pmd_alloc_one() is a wrapper for __get_free_pages(), sometimes

asm-generic: pgalloc: provide generic pmd_alloc_one() and pmd_free_one()

For most architectures that support >2 levels of page tables,
pmd_alloc_one() is a wrapper for __get_free_pages(), sometimes with
__GFP_ZERO and sometimes followed by memset(0) instead.

More elaborate versions on arm64 and x86 account memory for the user page
tables and call to pgtable_pmd_page_ctor() as the part of PMD page
initialization.

Move the arm64 version to include/asm-generic/pgalloc.h and use the
generic version on several architectures.

The pgtable_pmd_page_ctor() is a NOP when ARCH_ENABLE_SPLIT_PMD_PTLOCK is
not enabled, so there is no functional change for most architectures
except of the addition of __GFP_ACCOUNT for allocation of user page
tables.

The pmd_free() is a wrapper for free_page() in all the cases, so no
functional change here.

Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Pekka Enberg <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Abdul Haleem <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Cc: Satheesh Rajendran <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

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mm: treewide: clarify pgtable_page_{ctor,dtor}() naming

The naming of pgtable_page_{ctor,dtor}() seems to have confused a few
people, and until recently arm64 used these erroneously/pointlessly for

mm: treewide: clarify pgtable_page_{ctor,dtor}() naming

The naming of pgtable_page_{ctor,dtor}() seems to have confused a few
people, and until recently arm64 used these erroneously/pointlessly for
other levels of page table.

To make it incredibly clear that these only apply to the PTE level, and to
align with the naming of pgtable_pmd_page_{ctor,dtor}(), let's rename them
to pgtable_pte_page_{ctor,dtor}().

These changes were generated with the following shell script:

----
git grep -lw 'pgtable_page_.tor' | while read FILE; do
sed -i '{s/pgtable_page_ctor/pgtable_pte_page_ctor/}' $FILE;
sed -i '{s/pgtable_page_dtor/pgtable_pte_page_dtor/}' $FILE;
done
----

... with the documentation re-flowed to remain under 80 columns, and
whitespace fixed up in macros to keep backslashes aligned.

There should be no functional change as a result of this patch.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Mark Rutland <[email protected]>
Reviewed-by: Mike Rapoport <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> [m68k]
Cc: Anshuman Khandual <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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mm: remove quicklist page table caches

Patch series "mm: remove quicklist page table caches".

A while ago Nicholas proposed to remove quicklist page table caches [1].

I've rebased his patch on the

mm: remove quicklist page table caches

Patch series "mm: remove quicklist page table caches".

A while ago Nicholas proposed to remove quicklist page table caches [1].

I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.

[1] https://lore.kernel.org/linux-mm/[email protected]

This patch (of 3):

Remove page table allocator "quicklists". These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.

The numbers in the initial commit look interesting but probably don't
apply anymore. If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.

Also it might be better to instead make more general improvements to page
allocator if this is still so slow.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Nicholas Piggin <[email protected]>
Signed-off-by: Mike Rapoport <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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asm-generic, x86: introduce generic pte_{alloc,free}_one[_kernel]

Most architectures have identical or very similar implementation of
pte_alloc_one_kernel(), pte_alloc_one(), pte_free_kernel() and
p

asm-generic, x86: introduce generic pte_{alloc,free}_one[_kernel]

Most architectures have identical or very similar implementation of
pte_alloc_one_kernel(), pte_alloc_one(), pte_free_kernel() and
pte_free().

Add a generic implementation that can be reused across architectures and
enable its use on x86.

The generic implementation uses

GFP_KERNEL | __GFP_ZERO

for the kernel page tables and

GFP_KERNEL | __GFP_ZERO | __GFP_ACCOUNT

for the user page tables.

The "base" functions for PTE allocation, namely __pte_alloc_one_kernel()
and __pte_alloc_one() are intended for the architectures that require
additional actions after actual memory allocation or must use non-default
GFP flags.

x86 is switched to use generic pte_alloc_one_kernel(), pte_free_kernel() and
pte_free().

x86 still implements pte_alloc_one() to allow run-time control of GFP
flags required for "userpte" command line option.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Mike Rapoport <[email protected]>
Cc: Albert Ou <[email protected]>
Cc: Anshuman Khandual <[email protected]>
Cc: Anton Ivanov <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Greentime Hu <[email protected]>
Cc: Guan Xuetao <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Ley Foon Tan <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Paul Burton <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: Richard Kuo <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Russell King <[email protected]>
Cc: Sam Creasey <[email protected]>
Cc: Vincent Chen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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asm-generic: add generic NOMMU versions of some headers

Memory management in generic is highly architecture specific,
but on NOMMU architectures, it is mostly trivial, so just
add a default implemen

asm-generic: add generic NOMMU versions of some headers

Memory management in generic is highly architecture specific,
but on NOMMU architectures, it is mostly trivial, so just
add a default implementation in asm-generic that applies
to all NOMMU architectures.

The two files cache.h and cacheflush.h can possibly also
be used by architectures that have an MMU but never require
flushing the cache or have cache lines larger than 32 bytes.

Signed-off-by: Remis Lima Baima <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>

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