src/patches/suse-2.6.27.39/patches.arch/x2APIC_PATCH_11_of_41_72b1e22dfcad1daca6906148fd956ffe404bb0bc

   1 From: Suresh Siddha <suresh.b.siddha@intel.com>
   2 Subject: x64, x2apic/intr-remap: generic irq migration support from process context
   3 References: fate #303948 and fate #303984
   4 Patch-Mainline: queued for .28
   5 Commit-ID: 72b1e22dfcad1daca6906148fd956ffe404bb0bc
   6
   7 Signed-off-by: Thomas Renninger <trenn@suse.de>
   8
   9 Generic infrastructure for migrating the irq from the process context in the
  10 presence of CONFIG_GENERIC_PENDING_IRQ.
  11
  12 This will be used later for migrating irq in the presence of
  13 interrupt-remapping.
  14
  15 Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
  16 Cc: akpm@linux-foundation.org
  17 Cc: arjan@linux.intel.com
  18 Cc: andi@firstfloor.org
  19 Cc: ebiederm@xmission.com
  20 Cc: jbarnes@virtuousgeek.org
  21 Cc: steiner@sgi.com
  22 Signed-off-by: Ingo Molnar <mingo@elte.hu>
  23
  24 ---
  25  include/linux/irq.h |    1 +
  26  kernel/irq/manage.c |    9 ++++++++-
  27  2 files changed, 9 insertions(+), 1 deletion(-)
  28
  29 Index: linux-2.6.26/include/linux/irq.h
  30 ===================================================================
  31 --- linux-2.6.26.orig/include/linux/irq.h
  32 +++ linux-2.6.26/include/linux/irq.h
  33 @@ -62,6 +62,7 @@ typedef       void (*irq_flow_handler_t)(unsig
  34  #define IRQ_MOVE_PENDING       0x00200000      /* need to re-target IRQ destination */
  35  #define IRQ_NO_BALANCING       0x00400000      /* IRQ is excluded from balancing */
  36  #define IRQ_SPURIOUS_DISABLED  0x00800000      /* IRQ was disabled by the spurious trap */
  37 +#define IRQ_MOVE_PCNTXT        0x01000000      /* IRQ migration from process context */
  38
  39  #ifdef CONFIG_IRQ_PER_CPU
  40  # define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
  41 Index: linux-2.6.26/kernel/irq/manage.c
  42 ===================================================================
  43 --- linux-2.6.26.orig/kernel/irq/manage.c
  44 +++ linux-2.6.26/kernel/irq/manage.c
  45 @@ -89,7 +89,14 @@ int irq_set_affinity(unsigned int irq, c
  46         set_balance_irq_affinity(irq, cpumask);
  47
  48  #ifdef CONFIG_GENERIC_PENDING_IRQ
  49 -       set_pending_irq(irq, cpumask);
  50 +       if (desc->status & IRQ_MOVE_PCNTXT) {
  51 +               unsigned long flags;
  52 +
  53 +               spin_lock_irqsave(&desc->lock, flags);
  54 +               desc->chip->set_affinity(irq, cpumask);
  55 +               spin_unlock_irqrestore(&desc->lock, flags);
  56 +       } else
  57 +               set_pending_irq(irq, cpumask);
  58  #else
  59         desc->affinity = cpumask;
  60         desc->chip->set_affinity(irq, cpumask);