1. 28 Jan, 2019 40 commits
    • Jan Kiszka's avatar
      ipipe: Introduce ptrace resume notifier · 20b680ce
      Jan Kiszka authored
      This I-pipe hook reports the desired resumption mode to the subscriber:
      resume all process tasks or just single-step a particular one? The use
      case is to enable synchronous stopping / resuming of all head tasks of
      a ptraced real-time process.
      Signed-off-by: Jan Kiszka's avatarJan Kiszka <jan.kiszka@siemens.com>
      20b680ce
    • Jan Kiszka's avatar
      ipipe: Introduce infrastructure for userspace return notifier · fa7c59a8
      Jan Kiszka authored
      A little bit inspired by the kernel's user return notifier, this
      introduces an I-pipe hook before the kernel jumps back to a userspace
      context from the root domain. The hook is design to allow a switch back
      to the head domain, thus will not run through signal/preemption checks
      when returning from the callback over head. It is guaranteed to fire on
      return from interrupts and exceptions but may also fire on certain
      syscall-return paths.
      
      The first use case for the hook is resumption of ptraced tasks over
      head if they were stopped in that domain.
      
      This provides just the generic infrastructure, the invocation of
      __ipipe_notify_user_intreturn as well as the definition of
      TIP_USERINTRET are architecture-specific.
      Signed-off-by: Jan Kiszka's avatarJan Kiszka <jan.kiszka@siemens.com>
      fa7c59a8
    • Philippe Gerum's avatar
      a29a3e72
    • Philippe Gerum's avatar
      sched/core: ipipe: do not panic on failed migration to the head stage · 49021ef6
      Philippe Gerum authored
      __ipipe_migrate_head() should not BUG() unconditionally when failing
      to schedule out a thread, but rather let the real-time core handle the
      situation a bit more gracefully.
      49021ef6
    • Philippe Gerum's avatar
      ipipe: timer: prevent double-ack if host timer is not grabbed · cfd9c1ec
      Philippe Gerum authored
      Only timers stolen away from the host kernel should be early acked by
      the pipeline core. Otherwise, the regular IRQ handler associated to
      the timer would duplicate the action. The IRQ line is left masked,
      waiting for the IRQ flow handler to unmask it eventually.
      cfd9c1ec
    • Philippe Gerum's avatar
      ipipe: timer: notify co-kernel about entering ONESHOT_STOPPED mode · 2ca7e785
      Philippe Gerum authored
      Although we don't want to disable the hardware not to wreck the
      outstanding timing requests managed by the co-kernel, we should
      nevertheless notify it about entering the ONESHOT_STOPPED mode, so
      that it may disable the host tick emulation.
      2ca7e785
    • Philippe Gerum's avatar
      ipipe: timer: do not interpose on undefined handlers · 71e0d8f0
      Philippe Gerum authored
      There is no point in interposing on clock chip handlers for which
      there was no support originally. In some cases (oneshot_stopped), we
      may even get a kernel fault, jumping to a NULL address.
      
      Interpose on non-NULL original handlers only.
      71e0d8f0
    • Philippe Gerum's avatar
      ipipe: timer: resume hardware operations in oneshot handler · 36a084cf
      Philippe Gerum authored
      Although we won't allow disabling the hardware when the clock event
      logic switches a device to stopped mode - so that we won't affect the
      timer logic running on the head stage unexpectedly -, we still have to
      enable the hardware when switched (back) to oneshot mode, since it may
      have been stopped prior to interposing on the device in
      ipipe_timer_start().
      
      Failing to do so would leave the hardware shut down for both regular
      and Xenomai operations, with no mean to bring it up again.
      36a084cf
    • Philippe Gerum's avatar
      faf61b23
    • Philippe Gerum's avatar
      79a7a4ed
    • Philippe Gerum's avatar
      sched: idle: ipipe: drop spurious check · 22874dd3
      Philippe Gerum authored
      22874dd3
    • Philippe Gerum's avatar
      ebab58f5
    • Philippe Gerum's avatar
      printk: ipipe: defer vprintk() output · b3d05758
      Philippe Gerum authored
      b3d05758
    • Philippe Gerum's avatar
      stop_machine: fix build in !SMP case · f6e1d95f
      Philippe Gerum authored
      f6e1d95f
    • Philippe Gerum's avatar
    • Philippe Gerum's avatar
      ipipe: tick: revive the host tick after device grab · 2a5253f4
      Philippe Gerum authored
      Once the device was grabbed by ipipe_timer_start(), any pending host
      tick programmed in the hardware is basically lost, unknown to the
      co-kernel implementing the proxy handlers.
      
      Schedule a host event with the latest target time programmed to have
      the co-kernel know about the pending tick.
      2a5253f4
    • Philippe Gerum's avatar
      PM: ipipe: converge to Dovetail's CPUIDLE management · 5b2b6577
      Philippe Gerum authored
      Handle requests for transitioning to deeper C-states the way Dovetail
      does, which prevents us from losing the timer when grabbed by a
      co-kernel, in presence of a CPUIDLE driver.
      5b2b6577
    • Philippe Gerum's avatar
      genirq: ipipe: add local_irq_{enable, disable}_full() helpers · 98213c88
      Philippe Gerum authored
      Those helpers affect both the real (in CPU) and virtual interrupt
      states for the root stage, reconciling them.
      98213c88
    • Philippe Gerum's avatar
      ipipe: tick: cap timer_set op to device supported max · 1a7af26b
      Philippe Gerum authored
      At this chance, switch the min_delay_tick value to unsigned long to
      match the corresponding clockevent definition.
      1a7af26b
    • Philippe Gerum's avatar
      ipipe: tick: out-of-band devices require GENERIC_CLOCKEVENTS · 66bb7302
      Philippe Gerum authored
      Drop the legacy support for architectures not enabling the generic
      clock event framework, which would only provide periodic timing.
      
      We don't support any of those archs, and there is no point in running
      a Xenomai co-kernel on a hardware not capable of handling oneshot
      timing requests.
      66bb7302
    • Philippe Gerum's avatar
      thermal/drivers/hisi: drop spurious enable of auto-enable irq · a752f969
      Philippe Gerum authored
      Fixes the kernel warning below due to the second enable sneaking in
      between a thermal IRQ is handled by the hard interrupt handler - which
      disables it - and the IRQ thread eventually attempts to re-enable the
      interrupt - which was already enabled.
      
      [    0.405830] Unbalanced enable for IRQ 44
      [    0.406029] ------------[ cut here ]------------
      [    0.406035] WARNING: CPU: 3 PID: 1285 at kernel/irq/manage.c:525 __enable_irq+0x60/0x70
      [    0.406044] Modules linked in:
      [    0.406055] CPU: 3 PID: 1285 Comm: irq/44-hisi_the Not tainted 4.14.62-ipipe #2
      [    0.406060] Hardware name: HiKey Development Board (DT)
      [    0.406065] I-pipe domain: Linux
      [    0.406073] task: ffff8000336b0000 task.stack: ffff00000b9e0000
      [    0.406078] PC is at __enable_irq+0x60/0x70
      [    0.406083] LR is at __enable_irq+0x60/0x70
      [    0.406088] pc : [<ffff000008124d58>] lr : [<ffff000008124d58>] pstate: 60000045
      [    0.406093] sp : ffff00000b9e3c60
      [    0.406098] x29: ffff00000b9e3c60 x28: 0000000000000000
      [    0.406108] x27: ffff00000805ba40 x26: ffff8000336b0000
      [    0.406118] x25: ffff000008124000 x24: ffff00000b9e3d7c
      [    0.406128] x23: 0000000000000002 x22: ffff800033f39e88
      [    0.406138] x21: 000000000000bc40 x20: 000000000000002c
      [    0.406147] x19: ffff800034275200 x18: 0000000000000010
      [    0.406157] x17: 0000000000000007 x16: 0000000000000001
      [    0.406166] x15: ffff0000890014c7 x14: 0000000000000006
      [    0.406175] x13: ffff0000090014d5 x12: ffff000008eb34d0
      [    0.406184] x11: ffff000008eb3000 x10: 0000000005f5e0ff
      [    0.406193] x9 : ffff00000b9e3970 x8 : 0000000000000040
      [    0.406202] x7 : ffff000008e7c000 x6 : 0000000000000040
      [    0.406211] x5 : 0000000000000000 x4 : 0000000000000000
      [    0.406220] x3 : ffffffffffffffff x2 : ffff000008eb34f0
      [    0.406229] x1 : ffff8000336b0000 x0 : 000000000000001c
      [    0.406239] Call trace:
      [    0.406244] Exception stack(0xffff00000b9e3b20 to 0xffff00000b9e3c60)
      [    0.406249] 3b20: 000000000000001c ffff8000336b0000 ffff000008eb34f0 ffffffffffffffff
      [    0.406255] 3b40: 0000000000000000 0000000000000000 0000000000000040 ffff000008e7c000
      [    0.406261] 3b60: 0000000000000040 ffff00000b9e3970 0000000005f5e0ff ffff000008eb3000
      [    0.406267] 3b80: ffff000008eb34d0 ffff0000090014d5 0000000000000006 ffff0000890014c7
      [    0.406272] 3ba0: 0000000000000001 0000000000000007 0000000000000010 ffff800034275200
      [    0.406278] 3bc0: 000000000000002c 000000000000bc40 ffff800033f39e88 0000000000000002
      [    0.406284] 3be0: ffff00000b9e3d7c ffff000008124000 ffff8000336b0000 ffff00000805ba40
      [    0.406289] 3c00: 0000000000000000 ffff00000b9e3c60 ffff000008124d58 ffff00000b9e3c60
      [    0.406295] 3c20: ffff000008124d58 0000000060000045 0000000000000000 ffff800034275200
      [    0.406300] 3c40: ffffffffffffffff ffff000008e7c2b0 ffff00000b9e3c60 ffff000008124d58
      [    0.406306] [<ffff000008124d58>] __enable_irq+0x60/0x70
      [    0.406311] [<ffff000008124d9c>] enable_irq+0x34/0x68
      [    0.406317] [<ffff000008780320>] hisi_thermal_get_temp+0x160/0x198
      [    0.406322] [<ffff00000877b868>] of_thermal_get_temp+0x20/0x30
      [    0.406327] [<ffff00000877b0d4>] thermal_zone_get_temp+0x5c/0x138
      [    0.406332] [<ffff000008778740>] thermal_zone_device_update.part.4+0x20/0xb0
      [    0.406337] [<ffff0000087787f8>] thermal_zone_device_update+0x28/0x38
      [    0.406342] [<ffff00000877fe7c>] hisi_thermal_alarm_irq_thread+0x64/0x80
      [    0.406347] [<ffff0000081244e0>] irq_thread_fn+0x28/0x68
      [    0.406352] [<ffff000008124784>] irq_thread+0x114/0x1b0
      [    0.406357] [<ffff0000080f0384>] kthread+0xfc/0x128
      [    0.406362] [<ffff000008085274>] ret_from_fork+0x14/0x20
      [    0.406366] ---[ end trace 0e6011135c69587a ]---
      a752f969
    • Philippe Gerum's avatar
      98b0d629
    • Philippe Gerum's avatar
      ftrace: ipipe: rely on fully atomic stop_machine() handler · 0cae84b5
      Philippe Gerum authored
      Now that stop_machine() guarantees fully atomic execution of the stop
      routine via hard interrupt disabling, there is no point in using
      ipipe_critical_enter/exit() for the same purpose in order to patch the
      kernel text.
      0cae84b5
    • Philippe Gerum's avatar
      stop_machine: ipipe: ensure atomic stop-context operations · b23773c5
      Philippe Gerum authored
      stop_machine() guarantees that all online CPUs are spinning
      non-preemptible in a known code location before a subset of them may
      safely run a stop-context function. This service is typically useful
      for live patching the kernel code, or changing global memory mappings,
      so that no activity could run in parallel until the system has
      returned to a stable state after all stop-context operations have
      completed.
      
      When interrupt pipelining is enabled, we have to provide the same
      guarantee by restoring hard interrupt disabling where virtualizing the
      interrupt disable flag would defeat it.
      b23773c5
    • Philippe Gerum's avatar
      lockdep: ipipe: improve detection of out-of-band contexts · cda82720
      Philippe Gerum authored
      trace_hardirqs_on_virt[_caller]() must be invoked instead of
      trace_hardirqs_on[_caller]() from assembly sites before returning from
      an interrupt/fault, so that the virtual IRQ disable state is checked
      for before switching the tracer's logic state to ON.
      
      This is required as an interrupt may be received and handled by the
      pipeline core although not forwarded to the root domain, when
      interrupts are virtually disabled. In such a case, we want to
      reconcile the tracer's logic with the effect of interrupt pipelining.
      cda82720
    • Philippe Gerum's avatar
      lockdep: ipipe: make the logic aware of interrupt pipelining · a2ad86dd
      Philippe Gerum authored
      The lockdep engine will check for the current interrupt state as part
      of the locking validation process, which must encompass:
      
      - the CPU interrupt state
      - the current pipeline domain
      - the virtual interrupt disable flag
      
      so that we can traverse the tracepoints from any context sanely and
      safely.
      
      In addition trace_hardirqs_on_virt_caller() should be called by the
      arch-dependent code when tracking the interrupt state before returning
      to user-space after a kernel entry (exceptions, IRQ). This makes sure
      that the tracking logic only applies to the root domain, and considers
      the virtual disable flag exclusively.
      
      For instance, the kernel may be entered when interrupts are (only)
      virtually disabled for the root domain (i.e. stalled), and we should
      tell the IRQ tracing logic that IRQs are about to be enabled back only
      if the root domain is unstalled before leaving to user-space. In such
      a context, the state of the interrupt bit in the CPU would be
      irrelevant.
      a2ad86dd
    • Greg Gallagher's avatar
      drivers/dove: pmu: ipipe: fix build · e17b3b09
      Greg Gallagher authored
      e17b3b09
    • Gilles Chanteperdrix's avatar
      drivers/dove: pmu: ipipe: enable interrupt pipelining · 48fa9720
      Gilles Chanteperdrix authored
      Fix up the PMU controller driver of the Marvell Dove SoC in order to
      channel interrupts through the interrupt pipeline.
      48fa9720
    • Philippe Gerum's avatar
      pci: dwc: ipipe: enable interrupt pipelining · ec882cc9
      Philippe Gerum authored
      Fix up Synopsys's PCIE driver in order to channel interrupts through
      the interrupt pipeline.
      ec882cc9
    • Philippe Gerum's avatar
      pci: pcie-altera: ipipe: enable interrupt pipelining · b478b01d
      Philippe Gerum authored
      Fix up Altera's PCIE driver in order to channel interrupts through the
      interrupt pipeline.
      b478b01d
    • Philippe Gerum's avatar
      pinctrl: sunxi: ipipe: enable interrupt pipelining · 99b23c16
      Philippe Gerum authored
      Fix up the pin controller driver of the Allwinner A1x SoCs in order to
      channel interrupts through the interrupt pipeline.
      99b23c16
    • Philippe Gerum's avatar
      pinctrl: bcm2835: ipipe: enable interrupt pipelining · bba355b2
      Philippe Gerum authored
      Fix up the pin controller driver of the Broadcom 2835 SoC in order to
      channel interrupts through the interrupt pipeline.
      bba355b2
    • Greg Gallagher's avatar
      pinctrl: rockchip: enable interrupt pipelining · 63ac2938
      Greg Gallagher authored
      Fix up the pin controller driver of the Rockchip SoC in order to
      channel interrupts through the interrupt pipeline.
      63ac2938
    • Philippe Gerum's avatar
      serial/xilinx: enable raw console channel · bfd56702
      Philippe Gerum authored
      Enable the serial driver for raw_printk() output.
      bfd56702
    • Philippe Gerum's avatar
      serial/pl011: enable raw console channel · 8f3d79bd
      Philippe Gerum authored
      Enable the serial driver for raw_printk() output.
      8f3d79bd
    • Philippe Gerum's avatar
      serial/8250: enable raw console channel · 9cd170d0
      Philippe Gerum authored
      Enable the serial driver for raw_printk() output.
      9cd170d0
    • Philippe Gerum's avatar
      irqchip: gpcv2: enable interrupt pipelining · 89a2b981
      Philippe Gerum authored
      Fix up Freescale's general power controller driver in order to channel
      interrupts through the interrupt pipeline.
      89a2b981
    • Greg Gallagher's avatar
      irqchip: dw-apb-ictl: ipipe: fix build · b373ef51
      Greg Gallagher authored
      b373ef51
    • Greg Gallagher's avatar
      irqchip: brcmstb-l2: enable interrupt pipelining · eff49678
      Greg Gallagher authored
      Fix up Broadcom's Generic Set Top Box (Level 2) interrupt controller
      driver in order to channel interrupts through the interrupt pipeline.
      eff49678
    • Greg Gallagher's avatar
      irqchip: bcm7120-l2: enable interrupt pipelining · 9dd3841a
      Greg Gallagher authored
      Fixup Broadcom's BCM7120 (Level 2) interrupt controller driver in
      order to channel interrupts through the interrupt pipeline.
      9dd3841a