1. 26 6月, 2017 1 次提交
  2. 23 6月, 2017 3 次提交
    • T
      genirq: Introduce effective affinity mask · 0d3f5425
      Thomas Gleixner 提交于
      There is currently no way to evaluate the effective affinity mask of a
      given interrupt. Many irq chips allow only a single target CPU or a subset
      of CPUs in the affinity mask.
      
      Updating the mask at the time of setting the affinity to the subset would
      be counterproductive because information for cpu hotplug about assigned
      interrupt affinities gets lost. On CPU hotplug it's also pointless to force
      migrate an interrupt, which is not targeted at the CPU effectively. But
      currently the information is not available.
      
      Provide a seperate mask to be updated by the irq_chip->irq_set_affinity()
      implementations. Implement the read only proc files so the user can see the
      effective mask as well w/o trying to deduce it from /proc/interrupts.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Marc Zyngier <marc.zyngier@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Keith Busch <keith.busch@intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Christoph Hellwig <hch@lst.de>
      Link: http://lkml.kernel.org/r/20170619235446.247834245@linutronix.de
      0d3f5425
    • T
      genirq: Remove pointless gfp argument · 4ab764c3
      Thomas Gleixner 提交于
      All callers hand in GPF_KERNEL. No point to have an extra argument for
      that.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Marc Zyngier <marc.zyngier@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Keith Busch <keith.busch@intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Christoph Hellwig <hch@lst.de>
      Link: http://lkml.kernel.org/r/20170619235446.082544752@linutronix.de
      4ab764c3
    • T
      genirq/debugfs: Add proper debugfs interface · 087cdfb6
      Thomas Gleixner 提交于
      Debugging (hierarchical) interupt domains is tedious as there is no
      information about the hierarchy and no information about states of
      interrupts in the various domain levels.
      
      Add a debugfs directory 'irq' and subdirectories 'domains' and 'irqs'.
      
      The domains directory contains the domain files. The content is information
      about the domain. If the domain is part of a hierarchy then the parent
      domains are printed as well.
      
      # ls /sys/kernel/debug/irq/domains/
      default     INTEL-IR-2	    INTEL-IR-MSI-2  IO-APIC-IR-2  PCI-MSI
      DMAR-MSI    INTEL-IR-3	    INTEL-IR-MSI-3  IO-APIC-IR-3  unknown-1
      INTEL-IR-0  INTEL-IR-MSI-0  IO-APIC-IR-0    IO-APIC-IR-4  VECTOR
      INTEL-IR-1  INTEL-IR-MSI-1  IO-APIC-IR-1    PCI-HT
      
      # cat /sys/kernel/debug/irq/domains/VECTOR 
      name:   VECTOR
       size:   0
       mapped: 216
       flags:  0x00000041
      
      # cat /sys/kernel/debug/irq/domains/IO-APIC-IR-0 
      name:   IO-APIC-IR-0
       size:   24
       mapped: 19
       flags:  0x00000041
       parent: INTEL-IR-3
          name:   INTEL-IR-3
           size:   65536
           mapped: 167
           flags:  0x00000041
           parent: VECTOR
              name:   VECTOR
               size:   0
               mapped: 216
               flags:  0x00000041
      
      Unfortunately there is no per cpu information about the VECTOR domain (yet).
      
      The irqs directory contains detailed information about mapped interrupts.
      
      # cat /sys/kernel/debug/irq/irqs/3
      handler:  handle_edge_irq
      status:   0x00004000
      istate:   0x00000000
      ddepth:   1
      wdepth:   0
      dstate:   0x01018000
                  IRQD_IRQ_DISABLED
                  IRQD_SINGLE_TARGET
                  IRQD_MOVE_PCNTXT
      node:     0
      affinity: 0-143
      effectiv: 0
      pending:  
      domain:  IO-APIC-IR-0
       hwirq:   0x3
       chip:    IR-IO-APIC
        flags:   0x10
                   IRQCHIP_SKIP_SET_WAKE
       parent:
          domain:  INTEL-IR-3
           hwirq:   0x20000
           chip:    INTEL-IR
            flags:   0x0
           parent:
              domain:  VECTOR
               hwirq:   0x3
               chip:    APIC
                flags:   0x0
      
      This was developed to simplify the debugging of the managed affinity
      changes.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Keith Busch <keith.busch@intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Christoph Hellwig <hch@lst.de>
      Link: http://lkml.kernel.org/r/20170619235444.537566163@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      087cdfb6
  3. 26 5月, 2017 1 次提交
  4. 15 9月, 2016 1 次提交
  5. 14 9月, 2016 1 次提交
    • C
      genirq: Expose interrupt information through sysfs · ecb3f394
      Craig Gallek 提交于
      Information about interrupts is exposed via /proc/interrupts, but the
      format of that file has changed over kernel versions and differs across
      architectures. It also has varying column numbers depending on hardware.
      
      That all makes it hard for tools to parse.
      
      To solve this, expose the information through sysfs so each irq attribute
      is in a separate file in a consistent, machine parsable way.
      
      This feature is only available when both CONFIG_SPARSE_IRQ and
      CONFIG_SYSFS are enabled.
      
      Examples:
        /sys/kernel/irq/18/actions:	i801_smbus,ehci_hcd:usb1,uhci_hcd:usb7
        /sys/kernel/irq/18/chip_name:	IR-IO-APIC
        /sys/kernel/irq/18/hwirq:		18
        /sys/kernel/irq/18/name:		fasteoi
        /sys/kernel/irq/18/per_cpu_count:	0,0
        /sys/kernel/irq/18/type:		level
      
        /sys/kernel/irq/25/actions:	ahci0
        /sys/kernel/irq/25/chip_name:	IR-PCI-MSI
        /sys/kernel/irq/25/hwirq:		512000
        /sys/kernel/irq/25/name:		edge
        /sys/kernel/irq/25/per_cpu_count:	29036,0
        /sys/kernel/irq/25/type:		edge
      
      [ tglx: Moved kobject_del() under sparse_irq_lock, massaged code comments
        	and changelog ]
      Signed-off-by: NCraig Gallek <kraig@google.com>
      Cc: David Decotigny <decot@google.com>
      Link: http://lkml.kernel.org/r/1473783291-122873-1-git-send-email-kraigatgoog@gmail.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      ecb3f394
  6. 04 7月, 2016 2 次提交
  7. 02 5月, 2016 1 次提交
  8. 08 2月, 2016 1 次提交
  9. 14 12月, 2015 1 次提交
    • T
      genirq: Free irq_desc with rcu · 425a5072
      Thomas Gleixner 提交于
      The new VMD device driver needs to iterate over a list of
      "demultiplexing" interrupts. Protecting that list with a lock is not
      possible because the list is also required in code pathes which hold
      irq descriptor lock. Therefor the demultiplexing interrupt handler
      would create a lock inversion scenario if it calls a demux handler
      with the list protection lock held.
      
      A solution for this is to free the irq descriptor via RCU, so the
      list can be walked with rcu read lock held.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Keith Busch <keith.busch@intel.com>
      425a5072
  10. 16 9月, 2015 5 次提交
  11. 12 7月, 2015 1 次提交
  12. 12 6月, 2015 2 次提交
  13. 05 5月, 2015 2 次提交
  14. 13 12月, 2014 1 次提交
    • T
      genirq: Prevent proc race against freeing of irq descriptors · c291ee62
      Thomas Gleixner 提交于
      Since the rework of the sparse interrupt code to actually free the
      unused interrupt descriptors there exists a race between the /proc
      interfaces to the irq subsystem and the code which frees the interrupt
      descriptor.
      
      CPU0				CPU1
      				show_interrupts()
      				  desc = irq_to_desc(X);
      free_desc(desc)
        remove_from_radix_tree();
        kfree(desc);
      				  raw_spinlock_irq(&desc->lock);
      
      /proc/interrupts is the only interface which can actively corrupt
      kernel memory via the lock access. /proc/stat can only read from freed
      memory. Extremly hard to trigger, but possible.
      
      The interfaces in /proc/irq/N/ are not affected by this because the
      removal of the proc file is serialized in procfs against concurrent
      readers/writers. The removal happens before the descriptor is freed.
      
      For architectures which have CONFIG_SPARSE_IRQ=n this is a non issue
      as the descriptor is never freed. It's merely cleared out with the irq
      descriptor lock held. So any concurrent proc access will either see
      the old correct value or the cleared out ones.
      
      Protect the lookup and access to the irq descriptor in
      show_interrupts() with the sparse_irq_lock.
      
      Provide kstat_irqs_usr() which is protecting the lookup and access
      with sparse_irq_lock and switch /proc/stat to use it.
      
      Document the existing kstat_irqs interfaces so it's clear that the
      caller needs to take care about protection. The users of these
      interfaces are either not affected due to SPARSE_IRQ=n or already
      protected against removal.
      
      Fixes: 1f5a5b87 "genirq: Implement a sane sparse_irq allocator"
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: stable@vger.kernel.org
      c291ee62
  15. 03 9月, 2014 1 次提交
    • M
      genirq: Add irq_domain-aware core IRQ handler · 76ba59f8
      Marc Zyngier 提交于
      Calling irq_find_mapping from outside a irq_{enter,exit} section is
      unsafe and produces ugly messages if CONFIG_PROVE_RCU is enabled:
      If coming from the idle state, the rcu_read_lock call in irq_find_mapping
      will generate an unpleasant warning:
      
      <quote>
      ===============================
      [ INFO: suspicious RCU usage. ]
      3.16.0-rc1+ #135 Not tainted
      -------------------------------
      include/linux/rcupdate.h:871 rcu_read_lock() used illegally while idle!
      
      other info that might help us debug this:
      
      RCU used illegally from idle CPU!
      rcu_scheduler_active = 1, debug_locks = 0
      RCU used illegally from extended quiescent state!
      1 lock held by swapper/0/0:
       #0:  (rcu_read_lock){......}, at: [<ffffffc00010206c>]
      irq_find_mapping+0x4c/0x198
      </quote>
      
      As this issue is fairly widespread and involves at least three
      different architectures, a possible solution is to add a new
      handle_domain_irq entry point into the generic IRQ code that
      the interrupt controller code can call.
      
      This new function takes an irq_domain, and calls into irq_find_domain
      inside the irq_{enter,exit} block. An additional "lookup" parameter is
      used to allow non-domain architecture code to be replaced by this as well.
      
      Interrupt controllers can then be updated to use the new mechanism.
      
      This code is sitting behind a new CONFIG_HANDLE_DOMAIN_IRQ, as not all
      architectures implement set_irq_regs (yes, mn10300, I'm looking at you...).
      Reported-by: NVladimir Murzin <vladimir.murzin@arm.com>
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      Link: https://lkml.kernel.org/r/1409047421-27649-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>
      76ba59f8
  16. 06 7月, 2014 1 次提交
  17. 16 5月, 2014 5 次提交
  18. 28 4月, 2014 1 次提交
    • T
      genirq: x86: Ensure that dynamic irq allocation does not conflict · 62a08ae2
      Thomas Gleixner 提交于
      On x86 the allocation of irq descriptors may allocate interrupts which
      are in the range of the GSI interrupts. That's wrong as those
      interrupts are hardwired and we don't have the irq domain translation
      like PPC. So one of these interrupts can be hooked up later to one of
      the devices which are hard wired to it and the io_apic init code for
      that particular interrupt line happily reuses that descriptor with a
      completely different configuration so hell breaks lose.
      
      Inside x86 we allocate dynamic interrupts from above nr_gsi_irqs,
      except for a few usage sites which have not yet blown up in our face
      for whatever reason. But for drivers which need an irq range, like the
      GPIO drivers, we have no limit in place and we don't want to expose
      such a detail to a driver.
      
      To cure this introduce a function which an architecture can implement
      to impose a lower bound on the dynamic interrupt allocations.
      
      Implement it for x86 and set the lower bound to nr_gsi_irqs, which is
      the end of the hardwired interrupt space, so all dynamic allocations
      happen above.
      
      That not only allows the GPIO driver to work sanely, it also protects
      the bogus callsites of create_irq_nr() in hpet, uv, irq_remapping and
      htirq code. They need to be cleaned up as well, but that's a separate
      issue.
      Reported-by: NJin Yao <yao.jin@linux.intel.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
      Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Grant Likely <grant.likely@linaro.org>
      Cc: H. Peter Anvin <hpa@linux.intel.com>
      Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
      Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
      Cc: Krogerus Heikki <heikki.krogerus@intel.com>
      Cc: Linus Walleij <linus.walleij@linaro.org>
      Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1404241617360.28206@ionos.tec.linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      62a08ae2
  19. 05 3月, 2014 1 次提交
  20. 11 2月, 2014 1 次提交
  21. 15 5月, 2012 1 次提交
    • J
      genirq: export handle_edge_irq() and irq_to_desc() · 3911ff30
      Jiri Kosina 提交于
      Export handle_edge_irq() and irq_to_desc() to modules to allow them to
      do things such as
      
      	__irq_set_handler_locked(...., handle_edge_irq);
      
      This fixes
      
      	ERROR: "handle_edge_irq" [drivers/gpio/gpio-pch.ko] undefined!
      	ERROR: "irq_to_desc" [drivers/gpio/gpio-pch.ko] undefined!
      
      when gpio-pch is being built as a module.
      
      This was introduced by commit df9541a6 ("gpio: pch9: Use proper flow
      type handlers") that added
      
      	__irq_set_handler_locked(d->irq, handle_edge_irq);
      
      but handle_edge_irq() was not exported for modules (and inlined
      __irq_set_handler_locked() requires irq_to_desc() exported as well)
      Signed-off-by: NJiri Kosina <jkosina@suse.cz>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3911ff30
  22. 01 11月, 2011 1 次提交
    • P
      irq: don't put module.h into irq.h for tracking irqgen modules. · ec53cf23
      Paul Gortmaker 提交于
      Recent commit "irq: Track the  owner of irq descriptor" in
      commit ID b6873807 placed module.h into linux/irq.h
      but we are trying to limit module.h inclusion to just C files
      that really need it, due to its size and number of children
      includes.  This targets just reversing that include.
      
      Add in the basic "struct module" since that is all we really need
      to ensure things compile.  In theory, b6873807 should have added the
      module.h include to the irqdesc.h header as well, but the implicit
      module.h everywhere presence masked this from showing up.  So give
      it the "struct module" as well.
      
      As for the C files, irqdesc.c is only using THIS_MODULE, so it
      does not need module.h - give it export.h instead.  The C file
      irq/manage.c is now (as of b6873807) using try_module_get and
      module_put and so it needs module.h (which it already has).
      
      Also convert the irq_alloc_descs variants to macros, since all
      they really do is is call the __irq_alloc_descs primitive.
      This avoids including export.h and no debug info is lost.
      Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
      ec53cf23
  23. 03 10月, 2011 1 次提交
    • M
      genirq: Add support for per-cpu dev_id interrupts · 31d9d9b6
      Marc Zyngier 提交于
      The ARM GIC interrupt controller offers per CPU interrupts (PPIs),
      which are usually used to connect local timers to each core. Each CPU
      has its own private interface to the GIC, and only sees the PPIs that
      are directly connect to it.
      
      While these timers are separate devices and have a separate interrupt
      line to a core, they all use the same IRQ number.
      
      For these devices, request_irq() is not the right API as it assumes
      that an IRQ number is visible by a number of CPUs (through the
      affinity setting), but makes it very awkward to express that an IRQ
      number can be handled by all CPUs, and yet be a different interrupt
      line on each CPU, requiring a different dev_id cookie to be passed
      back to the handler.
      
      The *_percpu_irq() functions is designed to overcome these
      limitations, by providing a per-cpu dev_id vector:
      
      int request_percpu_irq(unsigned int irq, irq_handler_t handler,
      		   const char *devname, void __percpu *percpu_dev_id);
      void free_percpu_irq(unsigned int, void __percpu *);
      int setup_percpu_irq(unsigned int irq, struct irqaction *new);
      void remove_percpu_irq(unsigned int irq, struct irqaction *act);
      void enable_percpu_irq(unsigned int irq);
      void disable_percpu_irq(unsigned int irq);
      
      The API has a number of limitations:
      - no interrupt sharing
      - no threading
      - common handler across all the CPUs
      
      Once the interrupt is requested using setup_percpu_irq() or
      request_percpu_irq(), it must be enabled by each core that wishes its
      local interrupt to be delivered.
      
      Based on an initial patch by Thomas Gleixner.
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      Cc: linux-arm-kernel@lists.infradead.org
      Link: http://lkml.kernel.org/r/1316793788-14500-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      31d9d9b6
  24. 19 8月, 2011 1 次提交
  25. 28 7月, 2011 1 次提交
  26. 03 6月, 2011 2 次提交