19 Oct, 2016

2 commits

  • Merge the gup_flags cleanups from Lorenzo Stoakes:
    "This patch series adjusts functions in the get_user_pages* family such
    that desired FOLL_* flags are passed as an argument rather than
    implied by flags.

    The purpose of this change is to make the use of FOLL_FORCE explicit
    so it is easier to grep for and clearer to callers that this flag is
    being used. The use of FOLL_FORCE is an issue as it overrides missing
    VM_READ/VM_WRITE flags for the VMA whose pages we are reading
    from/writing to, which can result in surprising behaviour.

    The patch series came out of the discussion around commit 38e088546522
    ("mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing"),
    which addressed a BUG_ON() being triggered when a page was faulted in
    with PROT_NONE set but having been overridden by FOLL_FORCE.
    do_numa_page() was run on the assumption the page _must_ be one marked
    for NUMA node migration as an actual PROT_NONE page would have been
    dealt with prior to this code path, however FOLL_FORCE introduced a
    situation where this assumption did not hold.

    See

    https://marc.info/?l=linux-mm&m=147585445805166

    for the patch proposal"

    Additionally, there's a fix for an ancient bug related to FOLL_FORCE and
    FOLL_WRITE by me.

    [ This branch was rebased recently to add a few more acked-by's and
    reviewed-by's ]

    * gup_flag-cleanups:
    mm: replace access_process_vm() write parameter with gup_flags
    mm: replace access_remote_vm() write parameter with gup_flags
    mm: replace __access_remote_vm() write parameter with gup_flags
    mm: replace get_user_pages_remote() write/force parameters with gup_flags
    mm: replace get_user_pages() write/force parameters with gup_flags
    mm: replace get_vaddr_frames() write/force parameters with gup_flags
    mm: replace get_user_pages_locked() write/force parameters with gup_flags
    mm: replace get_user_pages_unlocked() write/force parameters with gup_flags
    mm: remove write/force parameters from __get_user_pages_unlocked()
    mm: remove write/force parameters from __get_user_pages_locked()
    mm: remove gup_flags FOLL_WRITE games from __get_user_pages()

    Linus Torvalds
     
  • This removes the 'write' argument from access_process_vm() and replaces
    it with 'gup_flags' as use of this function previously silently implied
    FOLL_FORCE, whereas after this patch callers explicitly pass this flag.

    We make this explicit as use of FOLL_FORCE can result in surprising
    behaviour (and hence bugs) within the mm subsystem.

    Signed-off-by: Lorenzo Stoakes
    Acked-by: Jesper Nilsson
    Acked-by: Michal Hocko
    Acked-by: Michael Ellerman
    Signed-off-by: Linus Torvalds

    Lorenzo Stoakes
     

15 Oct, 2016

3 commits

  • Pull more misc uaccess and vfs updates from Al Viro:
    "The rest of the stuff from -next (more uaccess work) + assorted fixes"

    * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
    score: traps: Add missing include file to fix build error
    fs/super.c: don't fool lockdep in freeze_super() and thaw_super() paths
    fs/super.c: fix race between freeze_super() and thaw_super()
    overlayfs: Fix setting IOP_XATTR flag
    iov_iter: kernel-doc import_iovec() and rw_copy_check_uvector()
    blackfin: no access_ok() for __copy_{to,from}_user()
    arm64: don't zero in __copy_from_user{,_inatomic}
    arm: don't zero in __copy_from_user_inatomic()/__copy_from_user()
    arc: don't leak bits of kernel stack into coredump
    alpha: get rid of tail-zeroing in __copy_user()

    Linus Torvalds
     
  • Al Viro
     
  • Pull kbuild updates from Michal Marek:

    - EXPORT_SYMBOL for asm source by Al Viro.

    This does bring a regression, because genksyms no longer generates
    checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is
    working on a patch to fix this.

    Plus, we are talking about functions like strcpy(), which rarely
    change prototypes.

    - Fixes for PPC fallout of the above by Stephen Rothwell and Nick
    Piggin

    - fixdep speedup by Alexey Dobriyan.

    - preparatory work by Nick Piggin to allow architectures to build with
    -ffunction-sections, -fdata-sections and --gc-sections

    - CONFIG_THIN_ARCHIVES support by Stephen Rothwell

    - fix for filenames with colons in the initramfs source by me.

    * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits)
    initramfs: Escape colons in depfile
    ppc: there is no clear_pages to export
    powerpc/64: whitelist unresolved modversions CRCs
    kbuild: -ffunction-sections fix for archs with conflicting sections
    kbuild: add arch specific post-link Makefile
    kbuild: allow archs to select link dead code/data elimination
    kbuild: allow architectures to use thin archives instead of ld -r
    kbuild: Regenerate genksyms lexer
    kbuild: genksyms fix for typeof handling
    fixdep: faster CONFIG_ search
    ia64: move exports to definitions
    sparc32: debride memcpy.S a bit
    [sparc] unify 32bit and 64bit string.h
    sparc: move exports to definitions
    ppc: move exports to definitions
    arm: move exports to definitions
    s390: move exports to definitions
    m68k: move exports to definitions
    alpha: move exports to actual definitions
    x86: move exports to actual definitions
    ...

    Linus Torvalds
     

11 Oct, 2016

1 commit

  • Pull protection keys syscall interface from Thomas Gleixner:
    "This is the final step of Protection Keys support which adds the
    syscalls so user space can actually allocate keys and protect memory
    areas with them. Details and usage examples can be found in the
    documentation.

    The mm side of this has been acked by Mel"

    * 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
    x86/pkeys: Update documentation
    x86/mm/pkeys: Do not skip PKRU register if debug registers are not used
    x86/pkeys: Fix pkeys build breakage for some non-x86 arches
    x86/pkeys: Add self-tests
    x86/pkeys: Allow configuration of init_pkru
    x86/pkeys: Default to a restrictive init PKRU
    pkeys: Add details of system call use to Documentation/
    generic syscalls: Wire up memory protection keys syscalls
    x86: Wire up protection keys system calls
    x86/pkeys: Allocation/free syscalls
    x86/pkeys: Make mprotect_key() mask off additional vm_flags
    mm: Implement new pkey_mprotect() system call
    x86/pkeys: Add fault handling for PF_PK page fault bit

    Linus Torvalds
     

08 Oct, 2016

2 commits

  • When doing an nmi backtrace of many cores, most of which are idle, the
    output is a little overwhelming and very uninformative. Suppress
    messages for cpus that are idling when they are interrupted and just
    emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".

    We do this by grouping all the cpuidle code together into a new
    .cpuidle.text section, and then checking the address of the interrupted
    PC to see if it lies within that section.

    This commit suitably tags x86 and tile idle routines, and only adds in
    the minimal framework for other architectures.

    Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
    Signed-off-by: Chris Metcalf
    Acked-by: Peter Zijlstra (Intel)
    Tested-by: Peter Zijlstra (Intel)
    Tested-by: Daniel Thompson [arm]
    Tested-by: Petr Mladek
    Cc: Aaron Tomlin
    Cc: Peter Zijlstra (Intel)
    Cc: "Rafael J. Wysocki"
    Cc: Russell King
    Cc: Thomas Gleixner
    Cc: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Chris Metcalf
     
  • This came to light when implementing native 64-bit atomics for ARCv2.

    The atomic64 self-test code uses CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
    to check whether atomic64_dec_if_positive() is available. It seems it
    was needed when not every arch defined it. However as of current code
    the Kconfig option seems needless

    - for CONFIG_GENERIC_ATOMIC64 it is auto-enabled in lib/Kconfig and a
    generic definition of API is present lib/atomic64.c
    - arches with native 64-bit atomics select it in arch/*/Kconfig and
    define the API in their headers

    So I see no point in keeping the Kconfig option

    Compile tested for:
    - blackfin (CONFIG_GENERIC_ATOMIC64)
    - x86 (!CONFIG_GENERIC_ATOMIC64)
    - ia64

    Link: http://lkml.kernel.org/r/1473703083-8625-3-git-send-email-vgupta@synopsys.com
    Signed-off-by: Vineet Gupta
    Cc: Richard Henderson
    Cc: Ivan Kokshaysky
    Cc: Matt Turner
    Cc: Russell King
    Cc: Catalin Marinas
    Cc: Will Deacon
    Cc: Ralf Baechle
    Cc: "James E.J. Bottomley"
    Cc: Helge Deller
    Cc: Benjamin Herrenschmidt
    Cc: Paul Mackerras
    Cc: Michael Ellerman
    Cc: Martin Schwidefsky
    Cc: Heiko Carstens
    Cc: "David S. Miller"
    Cc: Chris Metcalf
    Cc: Thomas Gleixner
    Cc: Ingo Molnar
    Cc: "H. Peter Anvin"
    Cc: Vineet Gupta
    Cc: Zhaoxiu Zeng
    Cc: Linus Walleij
    Cc: Alexander Potapenko
    Cc: Andrey Ryabinin
    Cc: Herbert Xu
    Cc: Ming Lin
    Cc: Arnd Bergmann
    Cc: Geert Uytterhoeven
    Cc: Peter Zijlstra
    Cc: Borislav Petkov
    Cc: Andi Kleen
    Cc: Boqun Feng
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Vineet Gupta
     

16 Sep, 2016

1 commit


10 Sep, 2016

1 commit


09 Sep, 2016

1 commit

  • This patch adds two new system calls:

    int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
    int pkey_free(int pkey);

    These implement an "allocator" for the protection keys
    themselves, which can be thought of as analogous to the allocator
    that the kernel has for file descriptors. The kernel tracks
    which numbers are in use, and only allows operations on keys that
    are valid. A key which was not obtained by pkey_alloc() may not,
    for instance, be passed to pkey_mprotect().

    These system calls are also very important given the kernel's use
    of pkeys to implement execute-only support. These help ensure
    that userspace can never assume that it has control of a key
    unless it first asks the kernel. The kernel does not promise to
    preserve PKRU (right register) contents except for allocated
    pkeys.

    The 'init_access_rights' argument to pkey_alloc() specifies the
    rights that will be established for the returned pkey. For
    instance:

    pkey = pkey_alloc(flags, PKEY_DENY_WRITE);

    will allocate 'pkey', but also sets the bits in PKRU[1] such that
    writing to 'pkey' is already denied.

    The kernel does not prevent pkey_free() from successfully freeing
    in-use pkeys (those still assigned to a memory range by
    pkey_mprotect()). It would be expensive to implement the checks
    for this, so we instead say, "Just don't do it" since sane
    software will never do it anyway.

    Any piece of userspace calling pkey_alloc() needs to be prepared
    for it to fail. Why? pkey_alloc() returns the same error code
    (ENOSPC) when there are no pkeys and when pkeys are unsupported.
    They can be unsupported for a whole host of reasons, so apps must
    be prepared for this. Also, libraries or LD_PRELOADs might steal
    keys before an application gets access to them.

    This allocation mechanism could be implemented in userspace.
    Even if we did it in userspace, we would still need additional
    user/kernel interfaces to tell userspace which keys are being
    used by the kernel internally (such as for execute-only
    mappings). Having the kernel provide this facility completely
    removes the need for these additional interfaces, or having an
    implementation of this in userspace at all.

    Note that we have to make changes to all of the architectures
    that do not use mman-common.h because we use the new
    PKEY_DENY_ACCESS/WRITE macros in arch-independent code.

    1. PKRU is the Protection Key Rights User register. It is a
    usermode-accessible register that controls whether writes
    and/or access to each individual pkey is allowed or denied.

    Signed-off-by: Dave Hansen
    Acked-by: Mel Gorman
    Cc: linux-arch@vger.kernel.org
    Cc: Dave Hansen
    Cc: arnd@arndb.de
    Cc: linux-api@vger.kernel.org
    Cc: linux-mm@kvack.org
    Cc: luto@kernel.org
    Cc: akpm@linux-foundation.org
    Cc: torvalds@linux-foundation.org
    Link: http://lkml.kernel.org/r/20160729163015.444FE75F@viggo.jf.intel.com
    Signed-off-by: Thomas Gleixner

    Dave Hansen
     

08 Aug, 2016

1 commit


05 Aug, 2016

1 commit

  • Pull RTC updates from Alexandre Belloni:
    "RTC for 4.8

    Cleanups:
    - huge cleanup of rtc-generic and char/genrtc this allowed to cleanup
    rtc-cmos, rtc-sh, rtc-m68k, rtc-powerpc and rtc-parisc
    - move mn10300 to rtc-cmos

    Subsystem:
    - fix wakealarms after hibernate
    - multiples fixes for rctest
    - simplify implementations of .read_alarm

    New drivers:
    - Maxim MAX6916

    Drivers:
    - ds1307: fix weekday
    - m41t80: add wakeup support
    - pcf85063: add support for PCF85063A variant
    - rv8803: extend i2c fix and other fixes
    - s35390a: fix alarm reading, this fixes instant reboot after
    shutdown for QNAP TS-41x
    - s3c: clock fixes"

    * tag 'rtc-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (65 commits)
    rtc: rv8803: Clear V1F when setting the time
    rtc: rv8803: Stop the clock while setting the time
    rtc: rv8803: Always apply the I²C workaround
    rtc: rv8803: Fix read day of week
    rtc: rv8803: Remove the check for valid time
    rtc: rv8803: Kconfig: Indicate rx8900 support
    rtc: asm9260: remove .owner field for driver
    rtc: at91sam9: Fix missing spin_lock_init()
    rtc: m41t80: add suspend handlers for alarm IRQ
    rtc: m41t80: make it a real error message
    rtc: pcf85063: Add support for the PCF85063A device
    rtc: pcf85063: fix year range
    rtc: hym8563: in .read_alarm set .tm_sec to 0 to signal minute accuracy
    rtc: explicitly set tm_sec = 0 for drivers with minute accurancy
    rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq()
    rtc: s3c: Remove unnecessary call to disable already disabled clock
    rtc: abx80x: use devm_add_action_or_reset()
    rtc: m41t80: use devm_add_action_or_reset()
    rtc: fix a typo and reduce three empty lines to one
    rtc: s35390a: improve two comments in .set_alarm
    ...

    Linus Torvalds
     

04 Aug, 2016

1 commit

  • The dma-mapping core and the implementations do not change the DMA
    attributes passed by pointer. Thus the pointer can point to const data.
    However the attributes do not have to be a bitfield. Instead unsigned
    long will do fine:

    1. This is just simpler. Both in terms of reading the code and setting
    attributes. Instead of initializing local attributes on the stack
    and passing pointer to it to dma_set_attr(), just set the bits.

    2. It brings safeness and checking for const correctness because the
    attributes are passed by value.

    Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
    )

    and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
    )

    Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
    Signed-off-by: Krzysztof Kozlowski
    Acked-by: Vineet Gupta
    Acked-by: Robin Murphy
    Acked-by: Hans-Christian Noren Egtvedt
    Acked-by: Mark Salter [c6x]
    Acked-by: Jesper Nilsson [cris]
    Acked-by: Daniel Vetter [drm]
    Reviewed-by: Bart Van Assche
    Acked-by: Joerg Roedel [iommu]
    Acked-by: Fabien Dessenne [bdisp]
    Reviewed-by: Marek Szyprowski [vb2-core]
    Acked-by: David Vrabel [xen]
    Acked-by: Konrad Rzeszutek Wilk [xen swiotlb]
    Acked-by: Joerg Roedel [iommu]
    Acked-by: Richard Kuo [hexagon]
    Acked-by: Geert Uytterhoeven [m68k]
    Acked-by: Gerald Schaefer [s390]
    Acked-by: Bjorn Andersson
    Acked-by: Hans-Christian Noren Egtvedt [avr32]
    Acked-by: Vineet Gupta [arc]
    Acked-by: Robin Murphy [arm64 and dma-iommu]
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Krzysztof Kozlowski
     

03 Aug, 2016

4 commits

  • Merge yet more updates from Andrew Morton:

    - the rest of ocfs2

    - various hotfixes, mainly MM

    - quite a bit of misc stuff - drivers, fork, exec, signals, etc.

    - printk updates

    - firmware

    - checkpatch

    - nilfs2

    - more kexec stuff than usual

    - rapidio updates

    - w1 things

    * emailed patches from Andrew Morton : (111 commits)
    ipc: delete "nr_ipc_ns"
    kcov: allow more fine-grained coverage instrumentation
    init/Kconfig: add clarification for out-of-tree modules
    config: add android config fragments
    init/Kconfig: ban CONFIG_LOCALVERSION_AUTO with allmodconfig
    relay: add global mode support for buffer-only channels
    init: allow blacklisting of module_init functions
    w1:omap_hdq: fix regression
    w1: add helper macro module_w1_family
    w1: remove need for ida and use PLATFORM_DEVID_AUTO
    rapidio/switches: add driver for IDT gen3 switches
    powerpc/fsl_rio: apply changes for RIO spec rev 3
    rapidio: modify for rev.3 specification changes
    rapidio: change inbound window size type to u64
    rapidio/idt_gen2: fix locking warning
    rapidio: fix error handling in mbox request/release functions
    rapidio/tsi721_dma: advance queue processing from transfer submit call
    rapidio/tsi721: add messaging mbox selector parameter
    rapidio/tsi721: add PCIe MRRS override parameter
    rapidio/tsi721_dma: add channel mask and queue size parameters
    ...

    Linus Torvalds
     
  • In general, there's no need for the "restore sigmask" flag to live in
    ti->flags. alpha, ia64, microblaze, powerpc, sh, sparc (64-bit only),
    tile, and x86 use essentially identical alternative implementations,
    placing the flag in ti->status.

    Replace those optimized implementations with an equally good common
    implementation that stores it in a bitfield in struct task_struct and
    drop the custom implementations.

    Additional architectures can opt in by removing their
    TIF_RESTORE_SIGMASK defines.

    Link: http://lkml.kernel.org/r/8a14321d64a28e40adfddc90e18a96c086a6d6f9.1468522723.git.luto@kernel.org
    Signed-off-by: Andy Lutomirski
    Tested-by: Michael Ellerman [powerpc]
    Cc: Richard Henderson
    Cc: Ivan Kokshaysky
    Cc: Matt Turner
    Cc: Tony Luck
    Cc: Fenghua Yu
    Cc: Michal Simek
    Cc: Benjamin Herrenschmidt
    Cc: Paul Mackerras
    Cc: Yoshinori Sato
    Cc: Rich Felker
    Cc: "David S. Miller"
    Cc: Chris Metcalf
    Cc: Peter Zijlstra
    Cc: Borislav Petkov
    Cc: Brian Gerst
    Cc: Dmitry Safonov
    Cc: Oleg Nesterov
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andy Lutomirski
     
  • There was only one use of __initdata_refok and __exit_refok

    __init_refok was used 46 times against 82 for __ref.

    Those definitions are obsolete since commit 312b1485fb50 ("Introduce new
    section reference annotations tags: __ref, __refdata, __refconst")

    This patch removes the following compatibility definitions and replaces
    them treewide.

    /* compatibility defines */
    #define __init_refok __ref
    #define __initdata_refok __refdata
    #define __exit_refok __ref

    I can also provide separate patches if necessary.
    (One patch per tree and check in 1 month or 2 to remove old definitions)

    [akpm@linux-foundation.org: coding-style fixes]
    Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be
    Signed-off-by: Fabian Frederick
    Cc: Ingo Molnar
    Cc: Sam Ravnborg
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Fabian Frederick
     
  • Pull kbuild updates from Michal Marek:

    - GCC plugin support by Emese Revfy from grsecurity, with a fixup from
    Kees Cook. The plugins are meant to be used for static analysis of
    the kernel code. Two plugins are provided already.

    - reduction of the gcc commandline by Arnd Bergmann.

    - IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada

    - bin2c fix by Michael Tautschnig

    - setlocalversion fix by Wolfram Sang

    * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
    gcc-plugins: disable under COMPILE_TEST
    kbuild: Abort build on bad stack protector flag
    scripts: Fix size mismatch of kexec_purgatory_size
    kbuild: make samples depend on headers_install
    Kbuild: don't add obj tree in additional includes
    Kbuild: arch: look for generated headers in obtree
    Kbuild: always prefix objtree in LINUXINCLUDE
    Kbuild: avoid duplicate include path
    Kbuild: don't add ../../ to include path
    vmlinux.lds.h: replace config_enabled() with IS_ENABLED()
    kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
    kconfig.h: use already defined macros for IS_REACHABLE() define
    export.h: use __is_defined() to check if __KSYM_* is defined
    kconfig.h: use __is_defined() to check if MODULE is defined
    kbuild: setlocalversion: print error to STDERR
    Add sancov plugin
    Add Cyclomatic complexity GCC plugin
    GCC plugin infrastructure
    Shared library support

    Linus Torvalds
     

27 Jul, 2016

1 commit


26 Jul, 2016

1 commit

  • Pull locking updates from Ingo Molnar:
    "The locking tree was busier in this cycle than the usual pattern - a
    couple of major projects happened to coincide.

    The main changes are:

    - implement the atomic_fetch_{add,sub,and,or,xor}() API natively
    across all SMP architectures (Peter Zijlstra)

    - add atomic_fetch_{inc/dec}() as well, using the generic primitives
    (Davidlohr Bueso)

    - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
    Waiman Long)

    - optimize smp_cond_load_acquire() on arm64 and implement LSE based
    atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
    on arm64 (Will Deacon)

    - introduce smp_acquire__after_ctrl_dep() and fix various barrier
    mis-uses and bugs (Peter Zijlstra)

    - after discovering ancient spin_unlock_wait() barrier bugs in its
    implementation and usage, strengthen its semantics and update/fix
    usage sites (Peter Zijlstra)

    - optimize mutex_trylock() fastpath (Peter Zijlstra)

    - ... misc fixes and cleanups"

    * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
    locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
    locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
    locking/static_keys: Fix non static symbol Sparse warning
    locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
    locking/atomic, arch/tile: Fix tilepro build
    locking/atomic, arch/m68k: Remove comment
    locking/atomic, arch/arc: Fix build
    locking/Documentation: Clarify limited control-dependency scope
    locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
    locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
    locking/atomic, arch/mips: Convert to _relaxed atomics
    locking/atomic, arch/alpha: Convert to _relaxed atomics
    locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
    locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
    locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
    locking/atomic: Fix atomic64_relaxed() bits
    locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
    locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
    locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
    locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
    ...

    Linus Torvalds
     

19 Jul, 2016

1 commit

  • There are very few files that need add an -I$(obj) gcc for the preprocessor
    or the assembler. For C files, we add always these for both the objtree and
    srctree, but for the other ones we require the Makefile to add them, and
    Kbuild then adds it for both trees.

    As a preparation for changing the meaning of the -I$(obj) directive to
    only refer to the srctree, this changes the two instances in arch/x86 to use
    an explictit $(objtree) prefix where needed, otherwise we won't find the
    headers any more, as reported by the kbuild 0day builder.

    arch/x86/realmode/rm/realmode.lds.S:75:20: fatal error: pasyms.h: No such file or directory

    Signed-off-by: Arnd Bergmann
    Signed-off-by: Michal Marek

    Arnd Bergmann
     

25 Jun, 2016

1 commit

  • This is the third version of the patchset previously sent [1]. I have
    basically only rebased it on top of 4.7-rc1 tree and dropped "dm: get
    rid of superfluous gfp flags" which went through dm tree. I am sending
    it now because it is tree wide and chances for conflicts are reduced
    considerably when we want to target rc2. I plan to send the next step
    and rename the flag and move to a better semantic later during this
    release cycle so we will have a new semantic ready for 4.8 merge window
    hopefully.

    Motivation:

    While working on something unrelated I've checked the current usage of
    __GFP_REPEAT in the tree. It seems that a majority of the usage is and
    always has been bogus because __GFP_REPEAT has always been about costly
    high order allocations while we are using it for order-0 or very small
    orders very often. It seems that a big pile of them is just a
    copy&paste when a code has been adopted from one arch to another.

    I think it makes some sense to get rid of them because they are just
    making the semantic more unclear. Please note that GFP_REPEAT is
    documented as

    * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt

    * _might_ fail. This depends upon the particular VM implementation.
    while !costly requests have basically nofail semantic. So one could
    reasonably expect that order-0 request with __GFP_REPEAT will not loop
    for ever. This is not implemented right now though.

    I would like to move on with __GFP_REPEAT and define a better semantic
    for it.

    $ git grep __GFP_REPEAT origin/master | wc -l
    111
    $ git grep __GFP_REPEAT | wc -l
    36

    So we are down to the third after this patch series. The remaining
    places really seem to be relying on __GFP_REPEAT due to large allocation
    requests. This still needs some double checking which I will do later
    after all the simple ones are sorted out.

    I am touching a lot of arch specific code here and I hope I got it right
    but as a matter of fact I even didn't compile test for some archs as I
    do not have cross compiler for them. Patches should be quite trivial to
    review for stupid compile mistakes though. The tricky parts are usually
    hidden by macro definitions and thats where I would appreciate help from
    arch maintainers.

    [1] http://lkml.kernel.org/r/1461849846-27209-1-git-send-email-mhocko@kernel.org

    This patch (of 19):

    __GFP_REPEAT has a rather weak semantic but since it has been introduced
    around 2.6.12 it has been ignored for low order allocations. Yet we
    have the full kernel tree with its usage for apparently order-0
    allocations. This is really confusing because __GFP_REPEAT is
    explicitly documented to allow allocation failures which is a weaker
    semantic than the current order-0 has (basically nofail).

    Let's simply drop __GFP_REPEAT from those places. This would allow to
    identify place which really need allocator to retry harder and formulate
    a more specific semantic for what the flag is supposed to do actually.

    Link: http://lkml.kernel.org/r/1464599699-30131-2-git-send-email-mhocko@kernel.org
    Signed-off-by: Michal Hocko
    Cc: "David S. Miller"
    Cc: "H. Peter Anvin"
    Cc: "James E.J. Bottomley"
    Cc: "Theodore Ts'o"
    Cc: Andy Lutomirski
    Cc: Benjamin Herrenschmidt
    Cc: Catalin Marinas
    Cc: Chen Liqin
    Cc: Chris Metcalf [for tile]
    Cc: Guan Xuetao
    Cc: Heiko Carstens
    Cc: Helge Deller
    Cc: Ingo Molnar
    Cc: Jan Kara
    Cc: John Crispin
    Cc: Lennox Wu
    Cc: Ley Foon Tan
    Cc: Martin Schwidefsky
    Cc: Matt Fleming
    Cc: Ralf Baechle
    Cc: Rich Felker
    Cc: Russell King
    Cc: Thomas Gleixner
    Cc: Vineet Gupta
    Cc: Will Deacon
    Cc: Yoshinori Sato
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Michal Hocko
     

16 Jun, 2016

3 commits

  • Generic code will construct {,_acquire,_release} versions by adding the
    required smp_mb__{before,after}_atomic() calls.

    Signed-off-by: Peter Zijlstra (Intel)
    Cc: Andrew Morton
    Cc: Ivan Kokshaysky
    Cc: Linus Torvalds
    Cc: Matt Turner
    Cc: Paul E. McKenney
    Cc: Peter Zijlstra
    Cc: Richard Henderson
    Cc: Thomas Gleixner
    Cc: linux-alpha@vger.kernel.org
    Cc: linux-arch@vger.kernel.org
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: Ingo Molnar

    Peter Zijlstra
     
  • Since all architectures have this implemented now natively, remove this
    dead code.

    Signed-off-by: Peter Zijlstra (Intel)
    Cc: Andrew Morton
    Cc: Linus Torvalds
    Cc: Paul E. McKenney
    Cc: Peter Zijlstra
    Cc: Thomas Gleixner
    Cc: linux-arch@vger.kernel.org
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: Ingo Molnar

    Peter Zijlstra
     
  • Implement FETCH-OP atomic primitives, these are very similar to the
    existing OP-RETURN primitives we already have, except they return the
    value of the atomic variable _before_ modification.

    This is especially useful for irreversible operations -- such as
    bitops (because it becomes impossible to reconstruct the state prior
    to modification).

    Signed-off-by: Peter Zijlstra (Intel)
    Cc: Andrew Morton
    Cc: Ivan Kokshaysky
    Cc: Linus Torvalds
    Cc: Matt Turner
    Cc: Paul E. McKenney
    Cc: Peter Zijlstra
    Cc: Richard Henderson
    Cc: Thomas Gleixner
    Cc: linux-alpha@vger.kernel.org
    Cc: linux-arch@vger.kernel.org
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: Ingo Molnar

    Peter Zijlstra
     

14 Jun, 2016

1 commit

  • This patch updates/fixes all spin_unlock_wait() implementations.

    The update is in semantics; where it previously was only a control
    dependency, we now upgrade to a full load-acquire to match the
    store-release from the spin_unlock() we waited on. This ensures that
    when spin_unlock_wait() returns, we're guaranteed to observe the full
    critical section we waited on.

    This fixes a number of spin_unlock_wait() users that (not
    unreasonably) rely on this.

    I also fixed a number of ticket lock versions to only wait on the
    current lock holder, instead of for a full unlock, as this is
    sufficient.

    Furthermore; again for ticket locks; I added an smp_rmb() in between
    the initial ticket load and the spin loop testing the current value
    because I could not convince myself the address dependency is
    sufficient, esp. if the loads are of different sizes.

    I'm more than happy to remove this smp_rmb() again if people are
    certain the address dependency does indeed work as expected.

    Note: PPC32 will be fixed independently

    Signed-off-by: Peter Zijlstra (Intel)
    Cc: Andrew Morton
    Cc: Linus Torvalds
    Cc: Paul E. McKenney
    Cc: Peter Zijlstra
    Cc: Thomas Gleixner
    Cc: chris@zankel.net
    Cc: cmetcalf@mellanox.com
    Cc: davem@davemloft.net
    Cc: dhowells@redhat.com
    Cc: james.hogan@imgtec.com
    Cc: jejb@parisc-linux.org
    Cc: linux@armlinux.org.uk
    Cc: mpe@ellerman.id.au
    Cc: ralf@linux-mips.org
    Cc: realmz6@gmail.com
    Cc: rkuo@codeaurora.org
    Cc: rth@twiddle.net
    Cc: schwidefsky@de.ibm.com
    Cc: tony.luck@intel.com
    Cc: vgupta@synopsys.com
    Cc: ysato@users.sourceforge.jp
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: Ingo Molnar

    Peter Zijlstra
     

08 Jun, 2016

2 commits

  • The rwsem-xadd count has been converted to an atomic variable and the
    rwsem code now directly uses atomic_long_add() and
    atomic_long_add_return(), so we can remove the arch implementations of
    rwsem_atomic_add() and rwsem_atomic_update().

    Signed-off-by: Jason Low
    Signed-off-by: Peter Zijlstra (Intel)
    Cc: Andrew Morton
    Cc: Arnd Bergmann
    Cc: Christoph Lameter
    Cc: Davidlohr Bueso
    Cc: Fenghua Yu
    Cc: Heiko Carstens
    Cc: Ivan Kokshaysky
    Cc: Jason Low
    Cc: Linus Torvalds
    Cc: Martin Schwidefsky
    Cc: Matt Turner
    Cc: Paul E. McKenney
    Cc: Peter Hurley
    Cc: Peter Zijlstra
    Cc: Richard Henderson
    Cc: Terry Rudd
    Cc: Thomas Gleixner
    Cc: Tim Chen
    Cc: Tony Luck
    Cc: Waiman Long
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: Ingo Molnar

    Jason Low
     
  • Convert the rwsem count variable to an atomic_long_t since we use it
    as an atomic variable. This also allows us to remove the
    rwsem_atomic_{add,update}() "abstraction" which would now be an unnecesary
    level of indirection. In follow up patches, we also remove the
    rwsem_atomic_{add,update}() definitions across the various architectures.

    Suggested-by: Peter Zijlstra
    Signed-off-by: Jason Low
    [ Build warning fixes on various architectures. ]
    Signed-off-by: Peter Zijlstra (Intel)
    Cc: Andrew Morton
    Cc: Davidlohr Bueso
    Cc: Fenghua Yu
    Cc: Heiko Carstens
    Cc: Jason Low
    Cc: Linus Torvalds
    Cc: Martin Schwidefsky
    Cc: Paul E. McKenney
    Cc: Peter Hurley
    Cc: Terry Rudd
    Cc: Thomas Gleixner
    Cc: Tim Chen
    Cc: Tony Luck
    Cc: Waiman Long
    Link: http://lkml.kernel.org/r/1465017963-4839-2-git-send-email-jason.low2@hpe.com
    Signed-off-by: Ingo Molnar

    Jason Low
     

04 Jun, 2016

2 commits

  • The genrtc driver serves no purpose on Alpha because it drives the
    same hardware as the original rtc.c driver, and the newer rtc-generic.c
    or rtc-cmos.c drivers on architectures that use the asm-generic/rtc.h
    header.

    The defconfig uses CONFIG_RTC=y, so this driver is not used by default.
    At one point it was used to abstract a quirk for the "Marvel" platform,
    but it does not do this any more after the code was moved into yet
    another driver in arch/alpha/kernel/rtc.c.

    Signed-off-by: Arnd Bergmann
    Acked-by: Geert Uytterhoeven
    Signed-off-by: Alexandre Belloni

    Arnd Bergmann
     
  • Drivers should not really include stuff from asm-generic directly,
    and the PC-style cmos rtc driver does this in order to reuse the
    mc146818 implementation of get_rtc_time/set_rtc_time rather than
    the architecture specific one for the architecture it gets built for.

    To make it more obvious what is going on, this moves and renames the
    two functions into include/linux/mc146818rtc.h, which holds the
    other mc146818 specific code. Ideally it would be in a .c file,
    but that would require extra infrastructure as the functions are
    called by multiple drivers with conflicting dependencies.

    With this change, the asm-generic/rtc.h header also becomes much
    more generic, so it can be reused more easily across any architecture
    that still relies on the genrtc driver.

    The only caller of the internal __get_rtc_time/__set_rtc_time
    functions is in arch/alpha/kernel/rtc.c, and we just change those
    over to the new naming.

    Signed-off-by: Arnd Bergmann
    Acked-by: Geert Uytterhoeven
    Signed-off-by: Alexandre Belloni

    Arnd Bergmann
     

21 May, 2016

2 commits

  • The binary GCD algorithm is based on the following facts:
    1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2)
    2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b)
    3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b)

    Even on x86 machines with reasonable division hardware, the binary
    algorithm runs about 25% faster (80% the execution time) than the
    division-based Euclidian algorithm.

    On platforms like Alpha and ARMv6 where division is a function call to
    emulation code, it's even more significant.

    There are two variants of the code here, depending on whether a fast
    __ffs (find least significant set bit) instruction is available. This
    allows the unpredictable branches in the bit-at-a-time shifting loop to
    be eliminated.

    If fast __ffs is not available, the "even/odd" GCD variant is used.

    I use the following code to benchmark:

    #include
    #include
    #include
    #include
    #include
    #include

    #define swap(a, b) \
    do { \
    a ^= b; \
    b ^= a; \
    a ^= b; \
    } while (0)

    unsigned long gcd0(unsigned long a, unsigned long b)
    {
    unsigned long r;

    if (a < b) {
    swap(a, b);
    }

    if (b == 0)
    return a;

    while ((r = a % b) != 0) {
    a = b;
    b = r;
    }

    return b;
    }

    unsigned long gcd1(unsigned long a, unsigned long b)
    {
    unsigned long r = a | b;

    if (!a || !b)
    return r;

    b >>= __builtin_ctzl(b);

    for (;;) {
    a >>= __builtin_ctzl(a);
    if (a == b)
    return a << __builtin_ctzl(r);

    if (a < b)
    swap(a, b);
    a -= b;
    }
    }

    unsigned long gcd2(unsigned long a, unsigned long b)
    {
    unsigned long r = a | b;

    if (!a || !b)
    return r;

    r &= -r;

    while (!(b & r))
    b >>= 1;

    for (;;) {
    while (!(a & r))
    a >>= 1;
    if (a == b)
    return a;

    if (a < b)
    swap(a, b);
    a -= b;
    a >>= 1;
    if (a & r)
    a += b;
    a >>= 1;
    }
    }

    unsigned long gcd3(unsigned long a, unsigned long b)
    {
    unsigned long r = a | b;

    if (!a || !b)
    return r;

    b >>= __builtin_ctzl(b);
    if (b == 1)
    return r & -r;

    for (;;) {
    a >>= __builtin_ctzl(a);
    if (a == 1)
    return r & -r;
    if (a == b)
    return a << __builtin_ctzl(r);

    if (a < b)
    swap(a, b);
    a -= b;
    }
    }

    unsigned long gcd4(unsigned long a, unsigned long b)
    {
    unsigned long r = a | b;

    if (!a || !b)
    return r;

    r &= -r;

    while (!(b & r))
    b >>= 1;
    if (b == r)
    return r;

    for (;;) {
    while (!(a & r))
    a >>= 1;
    if (a == r)
    return r;
    if (a == b)
    return a;

    if (a < b)
    swap(a, b);
    a -= b;
    a >>= 1;
    if (a & r)
    a += b;
    a >>= 1;
    }
    }

    static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = {
    gcd0, gcd1, gcd2, gcd3, gcd4,
    };

    #define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0]))

    #if defined(__x86_64__)

    #define rdtscll(val) do { \
    unsigned long __a,__d; \
    __asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \
    (val) = ((unsigned long long)__a) | (((unsigned long long)__d)<= start)
    ret = end - start;
    else
    ret = ~0ULL - start + 1 + end;

    *res = gcd_res;
    return ret;
    }

    #else

    static inline struct timespec read_time(void)
    {
    struct timespec time;
    clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time);
    return time;
    }

    static inline unsigned long long diff_time(struct timespec start, struct timespec end)
    {
    struct timespec temp;

    if ((end.tv_nsec - start.tv_nsec) < 0) {
    temp.tv_sec = end.tv_sec - start.tv_sec - 1;
    temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec;
    } else {
    temp.tv_sec = end.tv_sec - start.tv_sec;
    temp.tv_nsec = end.tv_nsec - start.tv_nsec;
    }

    return temp.tv_sec * 1000000000ULL + temp.tv_nsec;
    }

    static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
    unsigned long a, unsigned long b, unsigned long *res)
    {
    struct timespec start, end;
    unsigned long gcd_res;

    start = read_time();
    gcd_res = gcd(a, b);
    end = read_time();

    *res = gcd_res;
    return diff_time(start, end);
    }

    #endif

    static inline unsigned long get_rand()
    {
    if (sizeof(long) == 8)
    return (unsigned long)rand() << 32 | rand();
    else
    return rand();
    }

    int main(int argc, char **argv)
    {
    unsigned int seed = time(0);
    int loops = 100;
    int repeats = 1000;
    unsigned long (*res)[TEST_ENTRIES];
    unsigned long long elapsed[TEST_ENTRIES];
    int i, j, k;

    for (;;) {
    int opt = getopt(argc, argv, "n:r:s:");
    /* End condition always first */
    if (opt == -1)
    break;

    switch (opt) {
    case 'n':
    loops = atoi(optarg);
    break;
    case 'r':
    repeats = atoi(optarg);
    break;
    case 's':
    seed = strtoul(optarg, NULL, 10);
    break;
    default:
    /* You won't actually get here. */
    break;
    }
    }

    res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops);
    memset(elapsed, 0, sizeof(elapsed));

    srand(seed);
    for (j = 0; j < loops; j++) {
    unsigned long a = get_rand();
    /* Do we have args? */
    unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
    unsigned long long min_elapsed[TEST_ENTRIES];
    for (k = 0; k < repeats; k++) {
    for (i = 0; i < TEST_ENTRIES; i++) {
    unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]);
    if (k == 0 || min_elapsed[i] > tmp)
    min_elapsed[i] = tmp;
    }
    }
    for (i = 0; i < TEST_ENTRIES; i++)
    elapsed[i] += min_elapsed[i];
    }

    for (i = 0; i < TEST_ENTRIES; i++)
    printf("gcd%d: elapsed %llu\n", i, elapsed[i]);

    k = 0;
    srand(seed);
    for (j = 0; j < loops; j++) {
    unsigned long a = get_rand();
    unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
    for (i = 1; i < TEST_ENTRIES; i++) {
    if (res[j][i] != res[j][0])
    break;
    }
    if (i < TEST_ENTRIES) {
    if (k == 0) {
    k = 1;
    fprintf(stderr, "Error:\n");
    }
    fprintf(stderr, "gcd(%lu, %lu): ", a, b);
    for (i = 0; i < TEST_ENTRIES; i++)
    fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n");
    }
    }

    if (k == 0)
    fprintf(stderr, "PASS\n");

    free(res);

    return 0;
    }

    Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got:

    zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
    gcd0: elapsed 10174
    gcd1: elapsed 2120
    gcd2: elapsed 2902
    gcd3: elapsed 2039
    gcd4: elapsed 2812
    PASS
    zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
    gcd0: elapsed 9309
    gcd1: elapsed 2280
    gcd2: elapsed 2822
    gcd3: elapsed 2217
    gcd4: elapsed 2710
    PASS
    zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
    gcd0: elapsed 9589
    gcd1: elapsed 2098
    gcd2: elapsed 2815
    gcd3: elapsed 2030
    gcd4: elapsed 2718
    PASS
    zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
    gcd0: elapsed 9914
    gcd1: elapsed 2309
    gcd2: elapsed 2779
    gcd3: elapsed 2228
    gcd4: elapsed 2709
    PASS

    [akpm@linux-foundation.org: avoid #defining a CONFIG_ variable]
    Signed-off-by: Zhaoxiu Zeng
    Signed-off-by: George Spelvin
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Zhaoxiu Zeng
     
  • Define HAVE_EXIT_THREAD for archs which want to do something in
    exit_thread. For others, let's define exit_thread as an empty inline.

    This is a cleanup before we change the prototype of exit_thread to
    accept a task parameter.

    [akpm@linux-foundation.org: fix mips]
    Signed-off-by: Jiri Slaby
    Cc: "David S. Miller"
    Cc: "H. Peter Anvin"
    Cc: "James E.J. Bottomley"
    Cc: Aurelien Jacquiot
    Cc: Benjamin Herrenschmidt
    Cc: Catalin Marinas
    Cc: Chen Liqin
    Cc: Chris Metcalf
    Cc: Chris Zankel
    Cc: David Howells
    Cc: Fenghua Yu
    Cc: Geert Uytterhoeven
    Cc: Guan Xuetao
    Cc: Haavard Skinnemoen
    Cc: Hans-Christian Egtvedt
    Cc: Heiko Carstens
    Cc: Helge Deller
    Cc: Ingo Molnar
    Cc: Ivan Kokshaysky
    Cc: James Hogan
    Cc: Jeff Dike
    Cc: Jesper Nilsson
    Cc: Jiri Slaby
    Cc: Jonas Bonn
    Cc: Koichi Yasutake
    Cc: Lennox Wu
    Cc: Ley Foon Tan
    Cc: Mark Salter
    Cc: Martin Schwidefsky
    Cc: Matt Turner
    Cc: Max Filippov
    Cc: Michael Ellerman
    Cc: Michal Simek
    Cc: Mikael Starvik
    Cc: Paul Mackerras
    Cc: Peter Zijlstra
    Cc: Ralf Baechle
    Cc: Rich Felker
    Cc: Richard Henderson
    Cc: Richard Kuo
    Cc: Richard Weinberger
    Cc: Russell King
    Cc: Steven Miao
    Cc: Thomas Gleixner
    Cc: Tony Luck
    Cc: Vineet Gupta
    Cc: Will Deacon
    Cc: Yoshinori Sato
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jiri Slaby
     

20 May, 2016

1 commit

  • Pull PCI updates from Bjorn Helgaas:
    "Enumeration:
    - Refine PCI support check in pcibios_init() (Adrian-Ken Rueegsegger)
    - Provide common functions for ECAM mapping (Jayachandran C)
    - Allow all PCIe services on non-ACPI host bridges (Jon Derrick)
    - Remove return values from pcie_port_platform_notify() and relatives (Jon Derrick)
    - Widen portdrv service type from 4 bits to 8 bits (Keith Busch)
    - Add Downstream Port Containment portdrv service type (Keith Busch)
    - Add Downstream Port Containment driver (Keith Busch)

    Resource management:
    - Identify Enhanced Allocation (EA) BAR Equivalent resources in sysfs (Alex Williamson)
    - Supply CPU physical address (not bus address) to iomem_is_exclusive() (Bjorn Helgaas)
    - alpha: Call iomem_is_exclusive() for IORESOURCE_MEM, but not IORESOURCE_IO (Bjorn Helgaas)
    - Mark Broadwell-EP Home Agent 1 as having non-compliant BARs (Prarit Bhargava)
    - Disable all BAR sizing for devices with non-compliant BARs (Prarit Bhargava)
    - Move PCI I/O space management from OF to PCI core code (Tomasz Nowicki)

    PCI device hotplug:
    - acpiphp_ibm: Avoid uninitialized variable reference (Dan Carpenter)
    - Use cached copy of PCI_EXP_SLTCAP_HPC bit (Lukas Wunner)

    Virtualization:
    - Mark Intel i40e NIC INTx masking as broken (Alex Williamson)
    - Reverse standard ACS vs device-specific ACS enabling (Alex Williamson)
    - Work around Intel Sunrise Point PCH incorrect ACS capability (Alex Williamson)

    IOMMU:
    - Add pci_add_dma_alias() to abstract implementation (Bjorn Helgaas)
    - Move informational printk to pci_add_dma_alias() (Bjorn Helgaas)
    - Add support for multiple DMA aliases (Jacek Lawrynowicz)
    - Add DMA alias quirk for mic_x200_dma (Jacek Lawrynowicz)

    Thunderbolt:
    - Fix double free of drom buffer (Andreas Noever)
    - Add Intel Thunderbolt device IDs (Lukas Wunner)
    - Fix typos and magic number (Lukas Wunner)
    - Support 1st gen Light Ridge controller (Lukas Wunner)

    Generic host bridge driver:
    - Use generic ECAM API (Jayachandran C)

    Cavium ThunderX host bridge driver:
    - Don't clobber read-only bits in bridge config registers (David Daney)
    - Use generic ECAM API (Jayachandran C)

    Freescale i.MX6 host bridge driver:
    - Use enum instead of bool for variant indicator (Andrey Smirnov)
    - Implement reset sequence for i.MX6+ (Andrey Smirnov)
    - Factor out ref clock enable (Bjorn Helgaas)
    - Add initial imx6sx support (Christoph Fritz)
    - Add reset-gpio-active-high boolean property to DT (Petr Štetiar)
    - Add DT property for link gen, default to Gen1 (Tim Harvey)
    - dts: Specify imx6qp version of PCIe core (Andrey Smirnov)
    - dts: Fix PCIe reset GPIO polarity on Toradex Apalis Ixora (Petr Štetiar)

    Marvell Armada host bridge driver:
    - add DT binding for Marvell Armada 7K/8K PCIe controller (Thomas Petazzoni)
    - Add driver for Marvell Armada 7K/8K PCIe controller (Thomas Petazzoni)

    Marvell MVEBU host bridge driver:
    - Constify mvebu_pcie_pm_ops structure (Jisheng Zhang)
    - Use SET_NOIRQ_SYSTEM_SLEEP_PM_OPS for mvebu_pcie_pm_ops (Jisheng Zhang)

    Microsoft Hyper-V host bridge driver:
    - Report resources release after stopping the bus (Vitaly Kuznetsov)
    - Add explicit barriers to config space access (Vitaly Kuznetsov)

    Renesas R-Car host bridge driver:
    - Select PCI_MSI_IRQ_DOMAIN (Arnd Bergmann)

    Synopsys DesignWare host bridge driver:
    - Remove incorrect RC memory base/limit configuration (Gabriele Paoloni)
    - Move Root Complex setup code to dw_pcie_setup_rc() (Jisheng Zhang)

    TI Keystone host bridge driver:
    - Add error IRQ handler (Murali Karicheri)
    - Remove unnecessary goto statement (Murali Karicheri)

    Miscellaneous:
    - Fix spelling errors (Colin Ian King)"

    * tag 'pci-v4.7-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (48 commits)
    PCI: Disable all BAR sizing for devices with non-compliant BARs
    x86/PCI: Mark Broadwell-EP Home Agent 1 as having non-compliant BARs
    PCI: Identify Enhanced Allocation (EA) BAR Equivalent resources in sysfs
    PCI, of: Move PCI I/O space management to PCI core code
    PCI: generic, thunder: Use generic ECAM API
    PCI: Provide common functions for ECAM mapping
    PCI: hv: Add explicit barriers to config space access
    PCI: Use cached copy of PCI_EXP_SLTCAP_HPC bit
    PCI: Add Downstream Port Containment driver
    PCI: Add Downstream Port Containment portdrv service type
    PCI: Widen portdrv service type from 4 bits to 8 bits
    PCI: designware: Remove incorrect RC memory base/limit configuration
    PCI: hv: Report resources release after stopping the bus
    ARM: dts: imx6qp: Specify imx6qp version of PCIe core
    PCI: imx6: Implement reset sequence for i.MX6+
    PCI: imx6: Use enum instead of bool for variant indicator
    PCI: thunder: Don't clobber read-only bits in bridge config registers
    thunderbolt: Fix double free of drom buffer
    PCI: rcar: Select PCI_MSI_IRQ_DOMAIN
    PCI: armada: Add driver for Marvell Armada 7K/8K PCIe controller
    ...

    Linus Torvalds
     

18 May, 2016

2 commits

  • Pull GPIO updates from Linus Walleij:
    "This is the bulk of GPIO changes for kernel cycle v4.7:

    Core infrastructural changes:

    - Support for natively single-ended GPIO driver stages.

    This means that if the hardware has registers to configure open
    drain or open source configuration, we use that rather than (as we
    did before) try to emulate it by switching the line to an input to
    get high impedance.

    This is also documented throughly in Documentation/gpio/driver.txt
    for those of you who did not understand one word of what I just
    wrote.

    - Start to do away with the unnecessarily complex and unitelligible
    ARCH_REQUIRE_GPIOLIB and ARCH_WANT_OPTIONAL_GPIOLIB, another
    evolutional artifact from the time when the GPIO subsystem was
    unmaintained.

    Archs can now just select GPIOLIB and be done with it, cleanups to
    arches will trickle in for the next kernel. Some minor archs ACKed
    the changes immediately so these are included in this pull request.

    - Advancing the use of the data pointer inside the GPIO device for
    storing driver data by switching the PowerPC, Super-H Unicore and
    a few other subarches or subsystem drivers in ALSA SoC, Input,
    serial, SSB, staging etc to use it.

    - The initialization now reads the input/output state of the GPIO
    lines, so that each GPIO descriptor knows - if this callback is
    implemented - whether the line is input or output. This also
    reflects nicely in userspace "lsgpio".

    - It is now possible to name GPIO producer names, line names, from
    the device tree. (Platform data has been supported for a while).
    I bet we will get a similar mechanism for ACPI one of those days.
    This makes is possible to get sensible producer names for e.g.
    GPIO rails in "lsgpio" in userspace.

    New drivers:

    - New driver for the Loongson1.

    - The XLP driver now supports Broadcom Vulcan ARM64.

    - The IT87 driver now supports IT8620 and IT8628.

    - The PCA953X driver now supports Galileo Gen2.

    Driver improvements:

    - MCP23S08 was switched to use the gpiolib irqchip helpers and now
    also suppors level-triggered interrupts.

    - 74x164 and RCAR now supports the .set_multiple() callback

    - AMDPT was converted to use generic GPIO.

    - TC3589x, TPS65218, SX150X, F7188X, MENZ127, VX855, WM831X, WM8994
    support the new single ended callback for open drain and in some
    cases open source.

    - Implement the .get_direction() callback for a few more drivers like
    PL061, Xgene.

    Cleanups:

    - Paul Gortmaker combed through the drivers and de-modularized those
    who are not really modules.

    - Move the GPIO poweroff DT bindings to the power subdir where they
    belong.

    - Rename gpio-generic.c to gpio-mmio.c, which is much more to the
    point. That's what it is handling, nothing more, nothing less"

    * tag 'gpio-v4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (126 commits)
    MIPS: do away with ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB
    gpio: zevio: make it explicitly non-modular
    gpio: timberdale: make it explicitly non-modular
    gpio: stmpe: make it explicitly non-modular
    gpio: sodaville: make it explicitly non-modular
    pinctrl: sh-pfc: Let gpio_chip.to_irq() return zero on error
    gpio: dwapb: Add ACPI device ID for DWAPB GPIO controller on X-Gene platforms
    gpio: dt-bindings: add wd,mbl-gpio bindings
    gpio: of: make it possible to name GPIO lines
    gpio: make gpiod_to_irq() return negative for NO_IRQ
    gpio: xgene: implement .get_direction()
    gpio: xgene: Enable ACPI support for X-Gene GFC GPIO driver
    gpio: tegra: Implement gpio_get_direction callback
    gpio: set up initial state from .get_direction()
    gpio: rename gpio-generic.c into gpio-mmio.c
    gpio: generic: fix GPIO_GENERIC_PLATFORM is set to module case
    gpio: dwapb: add gpio-signaled acpi event support
    gpio: dwapb: convert device node to fwnode
    gpio: dwapb: remove name from dwapb_port_property
    gpio/qoriq: select IRQ_DOMAIN
    ...

    Linus Torvalds
     
  • Pull parallel filesystem directory handling update from Al Viro.

    This is the main parallel directory work by Al that makes the vfs layer
    able to do lookup and readdir in parallel within a single directory.
    That's a big change, since this used to be all protected by the
    directory inode mutex.

    The inode mutex is replaced by an rwsem, and serialization of lookups of
    a single name is done by a "in-progress" dentry marker.

    The series begins with xattr cleanups, and then ends with switching
    filesystems over to actually doing the readdir in parallel (switching to
    the "iterate_shared()" that only takes the read lock).

    A more detailed explanation of the process from Al Viro:
    "The xattr work starts with some acl fixes, then switches ->getxattr to
    passing inode and dentry separately. This is the point where the
    things start to get tricky - that got merged into the very beginning
    of the -rc3-based #work.lookups, to allow untangling the
    security_d_instantiate() mess. The xattr work itself proceeds to
    switch a lot of filesystems to generic_...xattr(); no complications
    there.

    After that initial xattr work, the series then does the following:

    - untangle security_d_instantiate()

    - convert a bunch of open-coded lookup_one_len_unlocked() to calls of
    that thing; one such place (in overlayfs) actually yields a trivial
    conflict with overlayfs fixes later in the cycle - overlayfs ended
    up switching to a variant of lookup_one_len_unlocked() sans the
    permission checks. I would've dropped that commit (it gets
    overridden on merge from #ovl-fixes in #for-next; proper resolution
    is to use the variant in mainline fs/overlayfs/super.c), but I
    didn't want to rebase the damn thing - it was fairly late in the
    cycle...

    - some filesystems had managed to depend on lookup/lookup exclusion
    for *fs-internal* data structures in a way that would break if we
    relaxed the VFS exclusion. Fixing hadn't been hard, fortunately.

    - core of that series - parallel lookup machinery, replacing
    ->i_mutex with rwsem, making lookup_slow() take it only shared. At
    that point lookups happen in parallel; lookups on the same name
    wait for the in-progress one to be done with that dentry.

    Surprisingly little code, at that - almost all of it is in
    fs/dcache.c, with fs/namei.c changes limited to lookup_slow() -
    making it use the new primitive and actually switching to locking
    shared.

    - parallel readdir stuff - first of all, we provide the exclusion on
    per-struct file basis, same as we do for read() vs lseek() for
    regular files. That takes care of most of the needed exclusion in
    readdir/readdir; however, these guys are trickier than lookups, so
    I went for switching them one-by-one. To do that, a new method
    '->iterate_shared()' is added and filesystems are switched to it
    as they are either confirmed to be OK with shared lock on directory
    or fixed to be OK with that. I hope to kill the original method
    come next cycle (almost all in-tree filesystems are switched
    already), but it's still not quite finished.

    - several filesystems get switched to parallel readdir. The
    interesting part here is dealing with dcache preseeding by readdir;
    that needs minor adjustment to be safe with directory locked only
    shared.

    Most of the filesystems doing that got switched to in those
    commits. Important exception: NFS. Turns out that NFS folks, with
    their, er, insistence on VFS getting the fuck out of the way of the
    Smart Filesystem Code That Knows How And What To Lock(tm) have
    grown the locking of their own. They had their own homegrown
    rwsem, with lookup/readdir/atomic_open being *writers* (sillyunlink
    is the reader there). Of course, with VFS getting the fuck out of
    the way, as requested, the actual smarts of the smart filesystem
    code etc. had become exposed...

    - do_last/lookup_open/atomic_open cleanups. As the result, open()
    without O_CREAT locks the directory only shared. Including the
    ->atomic_open() case. Backmerge from #for-linus in the middle of
    that - atomic_open() fix got brought in.

    - then comes NFS switch to saner (VFS-based ;-) locking, killing the
    homegrown "lookup and readdir are writers" kinda-sorta rwsem. All
    exclusion for sillyunlink/lookup is done by the parallel lookups
    mechanism. Exclusion between sillyunlink and rmdir is a real rwsem
    now - rmdir being the writer.

    Result: NFS lookups/readdirs/O_CREAT-less opens happen in parallel
    now.

    - the rest of the series consists of switching a lot of filesystems
    to parallel readdir; in a lot of cases ->llseek() gets simplified
    as well. One backmerge in there (again, #for-linus - rockridge
    fix)"

    * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (74 commits)
    ext4: switch to ->iterate_shared()
    hfs: switch to ->iterate_shared()
    hfsplus: switch to ->iterate_shared()
    hostfs: switch to ->iterate_shared()
    hpfs: switch to ->iterate_shared()
    hpfs: handle allocation failures in hpfs_add_pos()
    gfs2: switch to ->iterate_shared()
    f2fs: switch to ->iterate_shared()
    afs: switch to ->iterate_shared()
    befs: switch to ->iterate_shared()
    befs: constify stuff a bit
    isofs: switch to ->iterate_shared()
    get_acorn_filename(): deobfuscate a bit
    btrfs: switch to ->iterate_shared()
    logfs: no need to lock directory in lseek
    switch ecryptfs to ->iterate_shared
    9p: switch to ->iterate_shared()
    fat: switch to ->iterate_shared()
    romfs, squashfs: switch to ->iterate_shared()
    more trivial ->iterate_shared conversions
    ...

    Linus Torvalds
     

03 May, 2016

1 commit


26 Apr, 2016

2 commits


13 Apr, 2016

1 commit

  • Introduce ___down_write() for the fast path and reuse it for __down_write()
    resp. __down_write_killable() each using the respective generic slow path
    (rwsem_down_write_failed() resp. rwsem_down_write_failed_killable()).

    Signed-off-by: Michal Hocko
    Cc: Andrew Morton
    Cc: Chris Zankel
    Cc: David S. Miller
    Cc: Linus Torvalds
    Cc: Max Filippov
    Cc: Paul E. McKenney
    Cc: Peter Zijlstra
    Cc: Signed-off-by: Davidlohr Bueso
    Cc: Signed-off-by: Jason Low
    Cc: Thomas Gleixner
    Cc: Tony Luck
    Cc: linux-alpha@vger.kernel.org
    Cc: linux-arch@vger.kernel.org
    Cc: linux-ia64@vger.kernel.org
    Cc: linux-s390@vger.kernel.org
    Cc: linux-sh@vger.kernel.org
    Cc: linux-xtensa@linux-xtensa.org
    Cc: sparclinux@vger.kernel.org
    Link: http://lkml.kernel.org/r/1460041951-22347-8-git-send-email-mhocko@kernel.org
    Signed-off-by: Ingo Molnar

    Michal Hocko
     

23 Mar, 2016

1 commit