1. 03 3月, 2010 6 次提交
    • A
      USB: convert to the runtime PM framework · 9bbdf1e0
      Alan Stern 提交于
      This patch (as1329) converts the USB stack over to the PM core's
      runtime PM framework.  This involves numerous changes throughout
      usbcore, especially to hub.c and driver.c.  Perhaps the most notable
      change is that CONFIG_USB_SUSPEND now depends on CONFIG_PM_RUNTIME
      instead of CONFIG_PM.
      
      Several fields in the usb_device and usb_interface structures are no
      longer needed.  Some code which used to depend on CONFIG_USB_PM now
      depends on CONFIG_USB_SUSPEND (requiring some rearrangement of header
      files).
      
      The only visible change in behavior should be that following a system
      sleep (resume from RAM or resume from hibernation), autosuspended USB
      devices will be resumed just like everything else.  They won't remain
      suspended.  But if they aren't in use then they will naturally
      autosuspend again in a few seconds.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      9bbdf1e0
    • A
      USB: implement usb_enable_autosuspend · 088f7fec
      Alan Stern 提交于
      This patch (as1326) adds usb_enable_autosuspend() and
      usb_disable_autosuspend() routines for use by drivers.  If a driver
      knows that its device can handle suspends and resumes correctly, it
      can enable autosuspend all by itself.  This is equivalent to the user
      writing "auto" to the device's power/level attribute.
      
      The implementation differs slightly from what it used to be.  Now
      autosuspend is disabled simply by doing usb_autoresume_device() (to
      increment the usage counter) and enabled by doing
      usb_autosuspend_device() (to decrement the usage counter).
      
      The set_level() attribute method is updated to use the new routines,
      and the USB Power-Management documentation is updated.
      
      The patch adds a usb_enable_autosuspend() call to the hub driver's
      probe routine, allowing the special-case code for hubs in quirks.c to
      be removed.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      088f7fec
    • A
      usb: musb: Add 'extvbus' in musb_hdrc_platform_data · 5fc4e779
      Ajay Kumar Gupta 提交于
      Some of the board might use external Vbus power supply on musb
      interface which would require to program ULPI_BUSCONTROL register.
      
      Adding 'extvbus' flag which can be set from such boards which will
      be checked at musb driver files before programming ULPI_BUSCONTROL.
      Signed-off-by: NAjay Kumar Gupta <ajay.gupta@ti.com>
      Signed-off-by: NFelipe Balbi <felipe.balbi@nokia.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      5fc4e779
    • G
      USB: rename USB_SPEED_VARIABLE to USB_SPEED_WIRELESS · 551cdbbe
      Greg Kroah-Hartman 提交于
      It's really the wireless speed, so rename the thing to make
      more sense.  Based on a recommendation from David Vrabel
      
      Cc: David Vrabel <david.vrabel@csr.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      551cdbbe
    • O
      USB: storage: Never reset devices that will morph to an old mode · 5d398779
      Oliver Neukum 提交于
      Some devices must be switched to a new mode to fully use them.
      A reset would make them revert to the old mode. Therefore a reset
      must not be used for error handling with such devices.
      Signed-off-by: NOliver Neukum <oliver@neukum.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      5d398779
    • F
      USB: otg: add notifier support · e9a20171
      Felipe Balbi 提交于
      The notifier will be used to communicate usb events
      to other drivers like the charger chip.
      
      This can be used as source of information to kick
      usb charger detection as described by the USB
      Battery Charging Specification 1.1 and/or to
      pass bMaxPower field of selected usb_configuration
      to charger chip in order to use that information
      as input current on the charging profile
      setup.
      Signed-off-by: NFelipe Balbi <felipe.balbi@nokia.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      e9a20171
  2. 02 3月, 2010 3 次提交
    • B
      ata: Detect Delkin Devices compact flash · 4b7d1c05
      Ben Gardner 提交于
      I have a Delkin Devices compact flash card that isn't being recognized using the
      SATA/PATA drivers.
      The card is recognized and works with the deprecated ATA drivers.
      
      The error I am seeing is:
      ata1.00: failed to IDENTIFY (device reports invalid type, err_mask=0x0)
      
      I tracked it down to ata_id_is_cfa() in include/linux/ata.h.
      The Delkin card has id[0] set to 0x844a and id[83] set to 0.
      This isn't what the kernel expects and is probably incorrect.
      
      The simplest work-around is to add a check for 0x844a to ata_id_is_cfa().
      Signed-off-by: NBen Gardner <gardner.ben@gmail.com>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      4b7d1c05
    • A
      libata: Pass host flags into the pci helper · 16ea0fc9
      Alan Cox 提交于
      This allows parallel scan and the like to be set without having to stop
      using the existing full helper functions. This patch merely adds the argument
      and fixes up the callers. It doesn't undo the special cases already in the
      tree or add any new parallel callers.
      Signed-off-by: NAlan Cox <alan@linux.intel.com>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      16ea0fc9
    • T
      libata: implement spurious irq handling for SFF and apply it to piix · 27943620
      Tejun Heo 提交于
      Traditional IDE interface sucks in that it doesn't have a reliable IRQ
      pending bit, so if the controller raises IRQ while the driver is
      expecting it not to, the IRQ won't be cleared and eventually the IRQ
      line will be killed by interrupt subsystem.  Some controllers have
      non-standard mechanism to indicate IRQ pending so that this condition
      can be detected and worked around.
      
      This patch adds an optional operation ->sff_irq_check() which will be
      called for each port from the ata_sff_interrupt() if an unexpected
      interrupt is received.  If the operation returns %true,
      ->sff_check_status() and ->sff_irq_clear() will be cleared for the
      port.  Note that this doesn't mark the interrupt as handled so it
      won't prevent IRQ subsystem from killing the IRQ if this mechanism
      fails to clear the spurious IRQ.
      
      This patch also implements ->sff_irq_check() for ata_piix.  Note that
      this adds slight overhead to shared IRQ operation as IRQs which are
      destined for other controllers will trigger extra register accesses to
      check whether IDE interrupt is pending but this solves rare screaming
      IRQ cases and for some curious reason also helps weird BIOS related
      glitch on Samsung n130 as reported in bko#14314.
      
        http://bugzilla.kernel.org/show_bug.cgi?id=14314
      
      * piix_base_ops dropped as suggested by Sergei.
      
      * Spurious IRQ detection doesn't kick in anymore if polling qc is in
        progress.  This provides less protection but some controllers have
        possible data corruption issues if the wrong register is accessed
        while a command is in progress.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Reported-by: NJohannes Stezenbach <js@sig21.net>
      Reported-by: NHans Werner <hwerner4@gmx.de>
      Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
      Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      27943620
  3. 27 2月, 2010 9 次提交
    • P
      rcu: Make non-RCU_PROVE_LOCKING rcu_read_lock_sched_held() understand boot · 0b1c8727
      Paul E. McKenney 提交于
      Before the scheduler starts, all tasks are non-preemptible by
      definition. So, during that time, rcu_read_lock_sched_held()
      needs to always return "true".  This patch makes that be so
      for RCU_PROVE_LOCKING=n.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1267231138-27856-2-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      0b1c8727
    • M
      [S390] Define new s390 ELF note sections in elf.h · 73bfa5f2
      Michael Holzheu 提交于
      S390 ELF core dump currently only contains the PSW, the general purpose
      registers, the floating point registers and the access registers stored
      in PRSTATUS/PRFPREG note sections.
      For analyzing s390 kernel problems additional registers are important.
      In order to be able to include these registers to a kernel ELF core dump,
      this patch adds the following five new note sections to elf.h:
      
      * NT_S390_TIMER:   S390 timer register
      * NT_S390_TODCMP:  S390 TOD comparator register
      * NT_S390_TODPREG: S390 TOD programmable register
      * NT_S390_CTRS:    S390 control registers
      * NT_S390_PREFIX:  S390 prefix register
      
      The new note sections have been already defined and accepted in the upstream
      binutils package.
      Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      73bfa5f2
    • A
      USB: implement non-tree resume ordering constraints for PCI host controllers · 6d19c009
      Alan Stern 提交于
      This patch (as1331) adds non-tree ordering constraints needed for
      proper resume of PCI USB host controllers from hibernation.  The main
      issue is that non-high-speed devices must not be resumed before the
      high-speed root hub, because it is the ehci_bus_resume() routine which
      takes care of handing the device connection over to the companion
      controller.  If the device resume is attempted before the handover
      then the device won't be found and it will be treated as though it had
      disconnected.
      
      The patch adds a new field to the usb_bus structure; for each
      full/low-speed bus this field will contain a pointer to the companion
      high-speed bus (if one exists).  It is used during normal device
      resume; if the hs_companion pointer isn't NULL then we wait for the
      root-hub device on the hs_companion bus.
      
      A secondary issue is that an EHCI controlller shouldn't be resumed
      before any of its companions.  On some machines I have observed
      handovers failing if the companion controller is reinitialized after
      the handover.  Thus, the EHCI resume routine must wait for the
      companion controllers to be resumed.
      
      The patch also fixes a small bug in usb_hcd_pci_probe(); an error path
      jumps to the wrong label, causing a memory leak.
      
      [rjw: Fixed compilation for CONFIG_PM_SLEEP unset.]
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
      Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
      6d19c009
    • R
      PM: Allow device drivers to use dpm_wait() · f8824cee
      Rafael J. Wysocki 提交于
      There are some dependencies between devices (in particular, between
      EHCI USB controllers and their OHCI/UHCI siblings) which are not
      reflected by the structure of the device tree.  With synchronous
      suspend and resume these dependencies are taken into accout
      automatically, because the devices in question are always registered
      in the right order, but to meet these constraints with asynchronous
      suspend and resume the drivers of these devices will need to use
      dpm_wait() in their suspend/resume routines, so introduce a helper
      function allowing them to do that.
      Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
      f8824cee
    • R
      PM: Add facility for advanced testing of async suspend/resume · 5a2eb858
      Rafael J. Wysocki 提交于
      Add configuration switch CONFIG_PM_ADVANCED_DEBUG for compiling in
      extra PM debugging/testing code allowing one to access some
      PM-related attributes of devices from the user space via sysfs.
      
      If CONFIG_PM_ADVANCED_DEBUG is set, add sysfs attribute power/async
      for every device allowing the user space to access the device's
      power.async_suspend flag and modify it, if desired.
      Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
      5a2eb858
    • R
      PM: Asynchronous suspend and resume of devices · 5af84b82
      Rafael J. Wysocki 提交于
      Theoretically, the total time of system sleep transitions (suspend
      to RAM, hibernation) can be reduced by running suspend and resume
      callbacks of device drivers in parallel with each other.  However,
      there are dependencies between devices such that we're not allowed
      to suspend the parent of a device before suspending the device
      itself.  Analogously, we're not allowed to resume a device before
      resuming its parent.
      
      The most straightforward way to take these dependencies into accout
      is to start the async threads used for suspending and resuming
      devices at the core level, so that async_schedule() is called for
      each suspend and resume callback supposed to be executed
      asynchronously.
      
      For this purpose, introduce a new device flag, power.async_suspend,
      used to mark the devices whose suspend and resume callbacks are to be
      executed asynchronously (ie. in parallel with the main suspend/resume
      thread and possibly in parallel with each other) and helper function
      device_enable_async_suspend() allowing one to set power.async_suspend
      for given device (power.async_suspend is unset by default for all
      devices).  For each device with the power.async_suspend flag set the
      PM core will use async_schedule() to execute its suspend and resume
      callbacks.
      
      The async threads started for different devices as a result of
      calling async_schedule() are synchronized with each other and with
      the main suspend/resume thread with the help of completions, in the
      following way:
      (1) There is a completion, power.completion, for each device object.
      (2) Each device's completion is reset before calling async_schedule()
          for the device or, in the case of devices with the
          power.async_suspend flags unset, before executing the device's
          suspend and resume callbacks.
      (3) During suspend, right before running the bus type, device type
          and device class suspend callbacks for the device, the PM core
          waits for the completions of all the device's children to be
          completed.
      (4) During resume, right before running the bus type, device type and
          device class resume callbacks for the device, the PM core waits
          for the completion of the device's parent to be completed.
      (5) The PM core completes power.completion for each device right
          after the bus type, device type and device class suspend (or
          resume) callbacks executed for the device have returned.
      Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
      5af84b82
    • R
      PM / Runtime: Add sysfs switch for disabling device run-time PM · 53823639
      Rafael J. Wysocki 提交于
      Add new device sysfs attribute, power/control, allowing the user
      space to block the run-time power management of the devices.  If this
      attribute is set to "on", the driver of the device won't be able to power
      manage it at run time (without breaking the rules) and the device will
      always be in the full power state (except when the entire system goes
      into a sleep state).
      Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
      Acked-by: NAlan Stern <stern@rowland.harvard.edu>
      53823639
    • H
      V4L/DVB (14003): gspca_cpai1: New gspca subdriver for CPIA CPiA version 1 cams · 54e8bc5d
      Hans de Goede 提交于
      This new driver supports USB PIA CPiA version 1 cams, replacing the
      old v4l1 driver.
      Signed-off-by: NHans de Goede <hdegoede@redhat.com>
      Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      54e8bc5d
    • T
      V4L/DVB (13992): gspca_sn9c2028: New gspca subdriver · 5bdd00b9
      Theodore Kilgore 提交于
      New gspca subdriver adding support for SN9C2028 dual-mode cameras.
      Signed-off-by: NTheodore Kilgore <kilgota@banach.math.auburn.edu>
      Signed-off-by: NHans de Goede <hdegoede@redhat.com>
      Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      5bdd00b9
  4. 26 2月, 2010 10 次提交
  5. 25 2月, 2010 10 次提交
    • J
      tracing: Fix ftrace_event_call alignment for use with gcc 4.5 · 86c38a31
      Jeff Mahoney 提交于
      GCC 4.5 introduces behavior that forces the alignment of structures to
       use the largest possible value. The default value is 32 bytes, so if
       some structures are defined with a 4-byte alignment and others aren't
       declared with an alignment constraint at all - it will align at 32-bytes.
      
       For things like the ftrace events, this results in a non-standard array.
       When initializing the ftrace subsystem, we traverse the _ftrace_events
       section and call the initialization callback for each event. When the
       structures are misaligned, we could be treating another part of the
       structure (or the zeroed out space between them) as a function pointer.
      
       This patch forces the alignment for all the ftrace_event_call structures
       to 4 bytes.
      
       Without this patch, the kernel fails to boot very early when built with
       gcc 4.5.
      
       It's trivial to check the alignment of the members of the array, so it
       might be worthwhile to add something to the build system to do that
       automatically. Unfortunately, that only covers this case. I've asked one
       of the gcc developers about adding a warning when this condition is seen.
      
      Cc: stable@kernel.org
      Signed-off-by: NJeff Mahoney <jeffm@suse.com>
      LKML-Reference: <4B85770B.6010901@suse.com>
      Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      86c38a31
    • P
      rcu: Accelerate grace period if last non-dynticked CPU · 8bd93a2c
      Paul E. McKenney 提交于
      Currently, rcu_needs_cpu() simply checks whether the current CPU
      has an outstanding RCU callback, which means that the last CPU
      to go into dyntick-idle mode might wait a few ticks for the
      relevant grace periods to complete.  However, if all the other
      CPUs are in dyntick-idle mode, and if this CPU is in a quiescent
      state (which it is for RCU-bh and RCU-sched any time that we are
      considering going into dyntick-idle mode), then the grace period
      is instantly complete.
      
      This patch therefore repeatedly invokes the RCU grace-period
      machinery in order to force any needed grace periods to complete
      quickly.  It does so a limited number of times in order to
      prevent starvation by an RCU callback function that might pass
      itself to call_rcu().
      
      However, if any CPU other than the current one is not in
      dyntick-idle mode, fall back to simply checking (with fix to bug
      noted by Lai Jiangshan).  Also, take advantage of last
      grace-period forcing, the opportunity to do so noted by Steve
      Rostedt.  And apply simplified #ifdef condition suggested by
      Frederic Weisbecker.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-15-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      8bd93a2c
    • P
      vfs: Abstract rcu_dereference_check for files-fdtable use · af61b96b
      Paul E. McKenney 提交于
      Create an rcu_dereference_check_fdtable() that encapsulates the
      rcu_dereference_check() condition for fcheck_files() use.  This
      has the beneficial side-effect of getting rid of a very long
      line.
      Suggested-by: NPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-9-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      af61b96b
    • P
      vfs: Apply lockdep-based checking to rcu_dereference() uses · 7dc52157
      Paul E. McKenney 提交于
      Add lockdep-ified RCU primitives to alloc_fd(), files_fdtable()
      and fcheck_files().
      
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      LKML-Reference: <1266887105-1528-8-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      7dc52157
    • P
      sched: Use lockdep-based checking on rcu_dereference() · d11c563d
      Paul E. McKenney 提交于
      Update the rcu_dereference() usages to take advantage of the new
      lockdep-based checking.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-6-git-send-email-paulmck@linux.vnet.ibm.com>
      [ -v2: fix allmodconfig missing symbol export build failure on x86 ]
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d11c563d
    • P
      net: Add checking to rcu_dereference() primitives · a898def2
      Paul E. McKenney 提交于
      Update rcu_dereference() primitives to use new lockdep-based
      checking. The rcu_dereference() in __in6_dev_get() may be
      protected either by rcu_read_lock() or RTNL, per Eric Dumazet.
      The rcu_dereference() in __sk_free() is protected by the fact
      that it is never reached if an update could change it.  Check
      for this by using rcu_dereference_check() to verify that the
      struct sock's ->sk_wmem_alloc counter is zero.
      Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
      Acked-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-5-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a898def2
    • P
      rcu: Disable lockdep checking in RCU list-traversal primitives · 3120438a
      Paul E. McKenney 提交于
      The theory is that use of bare rcu_dereference() is more prone
      to error than use of the RCU list-traversal primitives.
      Therefore, disable lockdep RCU read-side critical-section
      checking in these primitives for the time being.  Once all of
      the rcu_dereference() uses have been dealt with, it may be time
      to re-enable lockdep checking for the RCU list-traversal
      primitives.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-4-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      3120438a
    • P
      rcu: Integrate rcu_dereference_check() message into lockdep · 0632eb3d
      Paul E. McKenney 提交于
      Make rcu_dereference_check() print the list of held locks in
      addition to the stack dump to ease debugging.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-3-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      0632eb3d
    • P
      rcu: Add lockdep-enabled variants of rcu_dereference() · c26d34a5
      Paul E. McKenney 提交于
      Make rcu_dereference() check for being in an RCU read-side
      critical section, and create rcu_dereference_bh(),
      rcu_dereference_sched(), and srcu_dereference() to check for the
      other flavors of RCU.  Also create rcu_dereference_raw() to
      avoid checking, and make rcu_dereference_check() use
      rcu_dereference_raw().
      Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-2-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      c26d34a5
    • P
      rcu: Introduce lockdep-based checking to RCU read-side primitives · 632ee200
      Paul E. McKenney 提交于
      Inspection is proving insufficient to catch all RCU misuses,
      which is understandable given that rcu_dereference() might be
      protected by any of four different flavors of RCU (RCU, RCU-bh,
      RCU-sched, and SRCU), and might also/instead be protected by any
      of a number of locking primitives. It is therefore time to
      enlist the aid of lockdep.
      
      This set of patches is inspired by earlier work by Peter
      Zijlstra and Thomas Gleixner, and takes the following approach:
      
      o	Set up separate lockdep classes for RCU, RCU-bh, and RCU-sched.
      
      o	Set up separate lockdep classes for each instance of SRCU.
      
      o	Create primitives that check for being in an RCU read-side
      	critical section.  These return exact answers if lockdep is
      	fully enabled, but if unsure, report being in an RCU read-side
      	critical section.  (We want to avoid false positives!)
      	The primitives are:
      
      	For RCU: rcu_read_lock_held(void)
      
      	For RCU-bh: rcu_read_lock_bh_held(void)
      
      	For RCU-sched: rcu_read_lock_sched_held(void)
      
      	For SRCU: srcu_read_lock_held(struct srcu_struct *sp)
      
      o	Add rcu_dereference_check(), which takes a second argument
      	in which one places a boolean expression based on the above
      	primitives and/or lockdep_is_held().
      
      o	A new kernel configuration parameter, CONFIG_PROVE_RCU, enables
      	rcu_dereference_check().  This depends on CONFIG_PROVE_LOCKING,
      	and should be quite helpful during the transition period while
      	CONFIG_PROVE_RCU-unaware patches are in flight.
      
      The existing rcu_dereference() primitive does no checking, but
      upcoming patches will change that.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-1-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      632ee200
  6. 24 2月, 2010 2 次提交