1. 12 Mar, 2013 1 commit
  2. 02 Mar, 2013 2 commits
  3. 24 Feb, 2013 1 commit
  4. 19 Feb, 2013 1 commit
  5. 14 Feb, 2013 3 commits
    • Martin Schwidefsky's avatar
      s390/mm: implement software dirty bits · abf09bed
      Martin Schwidefsky authored
      The s390 architecture is unique in respect to dirty page detection,
      it uses the change bit in the per-page storage key to track page
      modifications. All other architectures track dirty bits by means
      of page table entries. This property of s390 has caused numerous
      problems in the past, e.g. see git commit ef5d437f
      "mm: fix XFS oops due to dirty pages without buffers on s390".
      To avoid future issues in regard to per-page dirty bits convert
      s390 to a fault based software dirty bit detection mechanism. All
      user page table entries which are marked as clean will be hardware
      read-only, even if the pte is supposed to be writable. A write by
      the user process will trigger a protection fault which will cause
      the user pte to be marked as dirty and the hardware read-only bit
      is removed.
      With this change the dirty bit in the storage key is irrelevant
      for Linux as a host, but the storage key is still required for
      KVM guests. The effect is that page_test_and_clear_dirty and the
      related code can be removed. The referenced bit in the storage
      key is still used by the page_test_and_clear_young primitive to
      provide page age information.
      For page cache pages of mappings with mapping_cap_account_dirty
      there will not be any change in behavior as the dirty bit tracking
      already uses read-only ptes to control the amount of dirty pages.
      Only for swap cache pages and pages of mappings without
      mapping_cap_account_dirty there can be additional protection faults.
      To avoid an excessive number of additional faults the mk_pte
      primitive checks for PageDirty if the pgprot value allows for writes
      and pre-dirties the pte. That avoids all additional faults for
      tmpfs and shmem pages until these pages are added to the swap cache.
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
    • Heiko Carstens's avatar
      asm-generic/io.h: convert readX defines to functions · 7292e7e0
      Heiko Carstens authored
      E.g. readl is defined like this
       #define readl(addr) __le32_to_cpu(__raw_readl(addr))
      If a there is a readl() call that doesn't check the return value
      this will cause a compile warning on big endian machines due to
      the __le32_to_cpu macro magic.
      E.g. code like this:
      will generate the following compile warning:
      warning: value computed is not used [-Wunused-value]
      With this patch we get rid of dozens of compile warnings on s390.
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
    • Al Viro's avatar
      burying unused conditionals · d64008a8
      Al Viro authored
      can be assumed always set.
  6. 12 Feb, 2013 1 commit
  7. 11 Feb, 2013 4 commits
  8. 09 Feb, 2013 1 commit
  9. 04 Feb, 2013 1 commit
  10. 03 Feb, 2013 2 commits
  11. 27 Jan, 2013 3 commits
    • Frederic Weisbecker's avatar
      cputime: Generic on-demand virtual cputime accounting · abf917cd
      Frederic Weisbecker authored
      If we want to stop the tick further idle, we need to be
      able to account the cputime without using the tick.
      Virtual based cputime accounting solves that problem by
      hooking into kernel/user boundaries.
      However implementing CONFIG_VIRT_CPU_ACCOUNTING require
      low level hooks and involves more overhead. But we already
      have a generic context tracking subsystem that is required
      for RCU needs by archs which plan to shut down the tick
      outside idle.
      This patch implements a generic virtual based cputime
      accounting that relies on these generic kernel/user hooks.
      There are some upsides of doing this:
      - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING
      if context tracking is already built (already necessary for RCU in full
      tickless mode).
      - We can rely on the generic context tracking subsystem to dynamically
      (de)activate the hooks, so that we can switch anytime between virtual
      and tick based accounting. This way we don't have the overhead
      of the virtual accounting when the tick is running periodically.
      And one downside:
      - There is probably more overhead than a native virtual based cputime
      accounting. But this relies on hooks that are already set anyway.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
    • Frederic Weisbecker's avatar
      cputime: Move default nsecs_to_cputime() to jiffies based cputime file · ae8dda5c
      Frederic Weisbecker authored
      If the architecture doesn't provide an implementation of
      nsecs_to_cputime(), the cputime accounting core uses a
      default one that converts the nanoseconds to jiffies. However
      this only makes sense if we use the jiffies based cputime.
      For now it doesn't matter much because this API is only
      called on code that uses jiffies based cputime accounting.
      But the code may evolve and this API may be used more
      broadly in the future. Keeping this default implementation
      around is very error prone as it may introduce a bug and
      hide it on architectures that don't override this API.
      Fix this by moving this definition to the jiffies based
      cputime headers as it is the only place where it belongs to.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
    • Frederic Weisbecker's avatar
      cputime: Librarize per nsecs resolution cputime definitions · 39613766
      Frederic Weisbecker authored
      The full dynticks cputime accounting that we'll soon introduce
      will rely on sched_clock(). And its clock can have a per
      nanosecond granularity.
      To prepare for this, we need to have a cputime_t implementation
      that has this precision.
      ia64 virtual cputime accounting already uses that granularity
      so all we need is to librarize its implementation in the asm
      generic headers.
      Also librarize the default per jiffy granularity cputime_t
      as well so that we can easily pick either implementation
      depending on the cputime accounting config we choose.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
  12. 24 Jan, 2013 1 commit
  13. 22 Jan, 2013 2 commits
    • Shawn Guo's avatar
      gpio: devm_gpio_* support should not depend on GPIOLIB · 6a89a314
      Shawn Guo authored
      Some architectures (e.g. blackfin) provide gpio API without requiring
      GPIOLIB support (ARCH_WANT_OPTIONAL_GPIOLIB).  devm_gpio_* functions
      should also work for these architectures, since they do not really
      depend on GPIOLIB.
      Add a new option GPIO_DEVRES (enabled by default) to control the build
      of devres.c.  It also removes the empty version of devm_gpio_*
      functions for !GENERIC_GPIO build from linux/gpio.h, and moves the
      function declarations from asm-generic/gpio.h into linux/gpio.h.
      Signed-off-by: default avatarShawn Guo <shawn.guo@linaro.org>
      Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    • Shawn Guo's avatar
      gpio: fix warning of 'struct gpio_chip' declaration · d59b4eaa
      Shawn Guo authored
      The struct gpio_chip is only defined inside #ifdef CONFIG_GPIOLIB,
      but it's referenced by gpiochip_add_pin_range() and
      gpiochip_remove_pin_ranges() which are outside #ifdef CONFIG_GPIOLIB.
      Thus, we see the following warning when building blackfin image, where
      GPIOLIB is not required.
        CC      arch/blackfin/kernel/bfin_gpio.o
        CC      init/version.o
      In file included from arch/blackfin/include/asm/gpio.h:321,
                       from arch/blackfin/kernel/bfin_gpio.c:15:
      include/asm-generic/gpio.h:298: warning: 'struct gpio_chip' declared inside parameter list
      include/asm-generic/gpio.h:298: warning: its scope is only this definition or declaration, which is probably not what you want
      include/asm-generic/gpio.h:304: warning: 'struct gpio_chip' declared inside parameter list
      Move pinctrl trunk into #ifdef CONFIG_GPIOLIB to fix the warning,
      since it appears that pinctrl gpio range support depends on GPIOLIB.
      Signed-off-by: default avatarShawn Guo <shawn.guo@linaro.org>
      Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
  14. 18 Jan, 2013 1 commit
  15. 10 Jan, 2013 1 commit
    • Thomas Petazzoni's avatar
      irqchip: add basic infrastructure · f6e916b8
      Thomas Petazzoni authored
      With the recent creation of the drivers/irqchip/ directory, it is
      desirable to move irq controller drivers here. At the moment, the only
      driver here is irq-bcm2835, the driver for the irq controller found in
      the ARM BCM2835 SoC, present in Rasberry Pi systems. This irq
      controller driver was exporting its initialization function and its
      irq handling function through a header file in
      When proposing to also move another irq controller driver in
      drivers/irqchip, Rob Herring raised the very valid point that moving
      things to drivers/irqchip was good in order to remove more stuff from
      arch/arm, but if it means adding gazillions of headers files in
      include/linux/irqchip/, it would not be very nice.
      So, upon the suggestion of Rob Herring and Arnd Bergmann, this commit
      introduces a small infrastructure that defines a central
      irqchip_init() function in drivers/irqchip/irqchip.c, which is meant
      to be called as the ->init_irq() callback of ARM platforms. This
      function calls of_irq_init() with an array of match strings and init
      functions generated from a special linker section.
      Note that the irq controller driver initialization function is
      responsible for setting the global handle_arch_irq() variable, so that
      ARM platforms no longer have to define the ->handle_irq field in their
      DT_MACHINE structure.
      A global header, <linux/irqchip.h> is also added to expose the single
      irqchip_init() function to the reset of the kernel.
      A further commit moves the BCM2835 irq controller driver to this new
      small infrastructure, therefore removing the include/linux/irqchip/
      Signed-off-by: default avatarThomas Petazzoni <thomas.petazzoni@free-electrons.com>
      Reviewed-by: default avatarStephen Warren <swarren@wwwdotorg.org>
      Reviewed-by: default avatarRob Herring <rob.herring@calxeda.com>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      [rob.herring: reword commit message to reflect use of linker sections.]
      Signed-off-by: default avatarRob Herring <rob.herring@calxeda.com>
  16. 04 Jan, 2013 1 commit
    • Michal Hocko's avatar
      mm: limit mmu_gather batching to fix soft lockups on !CONFIG_PREEMPT · 53a59fc6
      Michal Hocko authored
      Since commit e303297e
       ("mm: extended batches for generic
      mmu_gather") we are batching pages to be freed until either
      tlb_next_batch cannot allocate a new batch or we are done.
      This works just fine most of the time but we can get in troubles with
      non-preemptible kernel (CONFIG_PREEMPT_NONE or CONFIG_PREEMPT_VOLUNTARY)
      on large machines where too aggressive batching might lead to soft
      lockups during process exit path (exit_mmap) because there are no
      scheduling points down the free_pages_and_swap_cache path and so the
      freeing can take long enough to trigger the soft lockup.
      The lockup is harmless except when the system is setup to panic on
      softlockup which is not that unusual.
      The simplest way to work around this issue is to limit the maximum
      number of batches in a single mmu_gather.  10k of collected pages should
      be safe to prevent from soft lockups (we would have 2ms for one) even if
      they are all freed without an explicit scheduling point.
      This patch doesn't add any new explicit scheduling points because it
      relies on zap_pmd_range during page tables zapping which calls
      cond_resched per PMD.
      The following lockup has been reported for 3.0 kernel with a huge
      process (in order of hundreds gigs but I do know any more details).
        BUG: soft lockup - CPU#56 stuck for 22s! [kernel:31053]
        Modules linked in: af_packet nfs lockd fscache auth_rpcgss nfs_acl sunrpc mptctl mptbase autofs4 binfmt_misc dm_round_robin dm_multipath bonding cpufreq_conservative cpufreq_userspace cpufreq_powersave pcc_cpufreq mperf microcode fuse loop osst sg sd_mod crc_t10dif st qla2xxx scsi_transport_fc scsi_tgt netxen_nic i7core_edac iTCO_wdt joydev e1000e serio_raw pcspkr edac_core iTCO_vendor_support acpi_power_meter rtc_cmos hpwdt hpilo button container usbhid hid dm_mirror dm_region_hash dm_log linear uhci_hcd ehci_hcd usbcore usb_common scsi_dh_emc scsi_dh_alua scsi_dh_hp_sw scsi_dh_rdac scsi_dh dm_snapshot pcnet32 mii edd dm_mod raid1 ext3 mbcache jbd fan thermal processor thermal_sys hwmon cciss scsi_mod
        Supported: Yes
        CPU 56
        Pid: 31053, comm: kernel Not tainted 3.0.31-0.9-default #1 HP ProLiant DL580 G7
        RIP: 0010:  _raw_spin_unlock_irqrestore+0x8/0x10
        RSP: 0018:ffff883ec1037af0  EFLAGS: 00000206
        RAX: 0000000000000e00 RBX: ffffea01a0817e28 RCX: ffff88803ffd9e80
        RDX: 0000000000000200 RSI: 0000000000000206 RDI: 0000000000000206
        RBP: 0000000000000002 R08: 0000000000000001 R09: ffff887ec724a400
        R10: 0000000000000000 R11: dead000000200200 R12: ffffffff8144c26e
        R13: 0000000000000030 R14: 0000000000000297 R15: 000000000000000e
        FS:  00007ed834282700(0000) GS:ffff88c03f200000(0000) knlGS:0000000000000000
        CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
        CR2: 000000000068b240 CR3: 0000003ec13c5000 CR4: 00000000000006e0
        DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
        DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
        Process kernel (pid: 31053, threadinfo ffff883ec1036000, task ffff883ebd5d4100)
        Call Trace:
        DWARF2 unwinder stuck at int_signal+0x12/0x17
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.cz>
      Cc: <stable@vger.kernel.org>	[3.0+]
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  17. 03 Jan, 2013 1 commit
    • Greg Kroah-Hartman's avatar
      include: remove __dev* attributes. · e389623a
      Greg Kroah-Hartman authored
      CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
      markings need to be removed.
      This change removes the use of __devinit from some include files that
      were previously missed.
      Based on patches originally written by Bill Pemberton, but redone by me
      in order to handle some of the coding style issues better, by hand.
      Cc: Bill Pemberton <wfp5p@virginia.edu>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
  18. 02 Jan, 2013 1 commit
    • Stephen Warren's avatar
      clocksource: add common of_clksrc_init() function · ae278a93
      Stephen Warren authored
      It is desirable to move all clocksource drivers to drivers/clocksource,
      yet each requires its own initialization function. We'd rather not
      pollute <linux/> with a header for each function. Instead, create a
      single of_clksrc_init() function which will determine which clocksource
      driver to initialize based on device tree.
      Based on a similar patch for drivers/irqchip by Thomas Petazzoni.
      Signed-off-by: default avatarStephen Warren <swarren@nvidia.com>
  19. 25 Dec, 2012 2 commits
  20. 17 Dec, 2012 1 commit
  21. 12 Dec, 2012 1 commit
  22. 11 Dec, 2012 2 commits
  23. 09 Dec, 2012 2 commits
  24. 30 Nov, 2012 1 commit
    • Jan Glauber's avatar
      s390/pci: base support · cd248341
      Jan Glauber authored
      Add PCI support for s390, (only 64 bit mode is supported by hardware):
      - PCI facility tests
      - PCI instructions: pcilg, pcistg, pcistb, stpcifc, mpcifc, rpcit
      - map readb/w/l/q and writeb/w/l/q to pcilg and pcistg instructions
      - pci_iomap implementation
      - memcpy_fromio/toio
      - pci_root_ops using special pcilg/pcistg
      - device, bus and domain allocation
      Signed-off-by: default avatarJan Glauber <jang@linux.vnet.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
  25. 28 Nov, 2012 3 commits