src/patches/suse-2.6.27.25/patches.xen/746-pirq-status-page.patch

   1 From: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/d545a95fca73
   2 # HG changeset 746+749+751+760 patch
   3 # User Keir Fraser <keir.fraser@citrix.com>
   4 # Date 1227879027 0
   5 # Node ID d545a95fca739d0b1963b73a9eb64ea64a244e76
   6 # Parent  2268be46c75ec6eddb7cd387af8a236a565f6140
   7 Subject: linux/x86: use shared page indicating the need for an EOI notification
   8 Patch-mainline: obsolete
   9
  10 Signed-off-by: Jan Beulich <jbeulich@novell.com>
  11
  12 From: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/cdc6729dc702
  13 Subject: evtchn: Fix the build.
  14 Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
  15
  16 From: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/ca213a56dba1
  17 Subject: evtchn, phydev: rename PHYSDEVOP_pirq_eoi_mfn to PHYSDEVOP_pirq_eoi_gmfn
  18
  19 Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
  20 Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
  21
  22 From: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/0d10be086a78
  23 Subject: linux/evtchn: allocate pirq_needs_eoi bitmap dynamically
  24
  25 Original patch from: Isaku Yamahata <yamahata@valinux.co.jp>
  26 Signed-off-by: Jan Beulich <jbeulich@novell.com>
  27
  28 --- head-2008-12-15.orig/drivers/xen/core/evtchn.c      2008-11-10 11:44:21.000000000 +0100
  29 +++ head-2008-12-15/drivers/xen/core/evtchn.c   2008-12-15 11:06:31.000000000 +0100
  30 @@ -35,6 +35,7 @@
  31  #include <linux/interrupt.h>
  32  #include <linux/sched.h>
  33  #include <linux/kernel_stat.h>
  34 +#include <linux/bootmem.h>
  35  #include <linux/version.h>
  36  #include <asm/atomic.h>
  37  #include <asm/system.h>
  38 @@ -123,9 +124,6 @@ DEFINE_PER_CPU(int, ipi_to_irq[NR_IPIS])
  39  /* Reference counts for bindings to IRQs. */
  40  static int irq_bindcount[NR_IRQS];
  41
  42 -/* Bitmap indicating which PIRQs require Xen to be notified on unmask. */
  43 -static DECLARE_BITMAP(pirq_needs_eoi, NR_PIRQS);
  44 -
  45  #ifdef CONFIG_SMP
  46
  47  static u8 cpu_evtchn[NR_EVENT_CHANNELS];
  48 @@ -756,16 +754,47 @@ static struct hw_interrupt_type dynirq_t
  49         .retrigger = resend_irq_on_evtchn,
  50  };
  51
  52 -static inline void pirq_unmask_notify(int irq)
  53 +/* Bitmap indicating which PIRQs require Xen to be notified on unmask. */
  54 +static int pirq_eoi_does_unmask;
  55 +static unsigned long *pirq_needs_eoi;
  56 +
  57 +static void pirq_unmask_and_notify(unsigned int evtchn, unsigned int irq)
  58  {
  59         struct physdev_eoi eoi = { .irq = evtchn_get_xen_pirq(irq) };
  60 -       if (unlikely(test_bit(irq - PIRQ_BASE, pirq_needs_eoi)))
  61 -               VOID(HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi));
  62 +
  63 +       if (pirq_eoi_does_unmask) {
  64 +               if (test_bit(eoi.irq, pirq_needs_eoi))
  65 +                       VOID(HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi));
  66 +               else
  67 +                       unmask_evtchn(evtchn);
  68 +       } else if (test_bit(irq - PIRQ_BASE, pirq_needs_eoi)) {
  69 +               if (smp_processor_id() != cpu_from_evtchn(evtchn)) {
  70 +                       struct evtchn_unmask unmask = { .port = evtchn };
  71 +                       struct multicall_entry mcl[2];
  72 +
  73 +                       mcl[0].op = __HYPERVISOR_event_channel_op;
  74 +                       mcl[0].args[0] = EVTCHNOP_unmask;
  75 +                       mcl[0].args[1] = (unsigned long)&unmask;
  76 +                       mcl[1].op = __HYPERVISOR_physdev_op;
  77 +                       mcl[1].args[0] = PHYSDEVOP_eoi;
  78 +                       mcl[1].args[1] = (unsigned long)&eoi;
  79 +
  80 +                       if (HYPERVISOR_multicall(mcl, 2))
  81 +                               BUG();
  82 +               } else {
  83 +                       unmask_evtchn(evtchn);
  84 +                       VOID(HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi));
  85 +               }
  86 +       } else
  87 +               unmask_evtchn(evtchn);
  88  }
  89
  90  static inline void pirq_query_unmask(int irq)
  91  {
  92         struct physdev_irq_status_query irq_status;
  93 +
  94 +       if (pirq_eoi_does_unmask)
  95 +               return;
  96         irq_status.irq = evtchn_get_xen_pirq(irq);
  97         if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
  98                 irq_status.flags = 0;
  99 @@ -806,8 +835,7 @@ static unsigned int startup_pirq(unsigne
 100         irq_info[irq] = mk_irq_info(IRQT_PIRQ, bind_pirq.pirq, evtchn);
 101
 102   out:
 103 -       unmask_evtchn(evtchn);
 104 -       pirq_unmask_notify(irq);
 105 +       pirq_unmask_and_notify(evtchn, irq);
 106
 107         return 0;
 108  }
 109 @@ -859,10 +887,8 @@ static void end_pirq(unsigned int irq)
 110         if ((irq_desc[irq].status & (IRQ_DISABLED|IRQ_PENDING)) ==
 111             (IRQ_DISABLED|IRQ_PENDING)) {
 112                 shutdown_pirq(irq);
 113 -       } else if (VALID_EVTCHN(evtchn)) {
 114 -               unmask_evtchn(evtchn);
 115 -               pirq_unmask_notify(irq);
 116 -       }
 117 +       } else if (VALID_EVTCHN(evtchn))
 118 +               pirq_unmask_and_notify(evtchn, irq);
 119  }
 120
 121  static struct hw_interrupt_type pirq_type = {
 122 @@ -1012,6 +1038,14 @@ void irq_resume(void)
 123
 124         init_evtchn_cpu_bindings();
 125
 126 +       if (pirq_eoi_does_unmask) {
 127 +               struct physdev_pirq_eoi_gmfn eoi_gmfn;
 128 +
 129 +               eoi_gmfn.gmfn = virt_to_machine(pirq_needs_eoi) >> PAGE_SHIFT;
 130 +               if (HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn, &eoi_gmfn))
 131 +                       BUG();
 132 +       }
 133 +
 134         /* New event-channel space is not 'live' yet. */
 135         for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
 136                 mask_evtchn(evtchn);
 137 @@ -1098,9 +1132,16 @@ int evtchn_get_xen_pirq(int irq)
 138  void __init xen_init_IRQ(void)
 139  {
 140         unsigned int i;
 141 +       struct physdev_pirq_eoi_gmfn eoi_gmfn;
 142
 143         init_evtchn_cpu_bindings();
 144
 145 +       pirq_needs_eoi = alloc_bootmem_pages(sizeof(unsigned long)
 146 +               * BITS_TO_LONGS(ALIGN(NR_PIRQS, PAGE_SIZE * 8)));
 147 +       eoi_gmfn.gmfn = virt_to_machine(pirq_needs_eoi) >> PAGE_SHIFT;
 148 +       if (HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn, &eoi_gmfn) == 0)
 149 +               pirq_eoi_does_unmask = 1;
 150 +
 151         /* No event channels are 'live' right now. */
 152         for (i = 0; i < NR_EVENT_CHANNELS; i++)
 153                 mask_evtchn(i);
 154 --- head-2008-12-15.orig/include/xen/interface/physdev.h        2008-11-25 12:35:56.000000000 +0100
 155 +++ head-2008-12-15/include/xen/interface/physdev.h     2008-12-08 13:22:39.000000000 +0100
 156 @@ -41,6 +41,21 @@ typedef struct physdev_eoi physdev_eoi_t
 157  DEFINE_XEN_GUEST_HANDLE(physdev_eoi_t);
 158
 159  /*
 160 + * Register a shared page for the hypervisor to indicate whether the guest
 161 + * must issue PHYSDEVOP_eoi. The semantics of PHYSDEVOP_eoi change slightly
 162 + * once the guest used this function in that the associated event channel
 163 + * will automatically get unmasked. The page registered is used as a bit
 164 + * array indexed by Xen's PIRQ value.
 165 + */
 166 +#define PHYSDEVOP_pirq_eoi_gmfn         17
 167 +struct physdev_pirq_eoi_gmfn {
 168 +    /* IN */
 169 +    xen_pfn_t gmfn;
 170 +};
 171 +typedef struct physdev_pirq_eoi_gmfn physdev_pirq_eoi_gmfn_t;
 172 +DEFINE_XEN_GUEST_HANDLE(physdev_pirq_eoi_gmfn_t);
 173 +
 174 +/*
 175   * Query the status of an IRQ line.
 176   * @arg == pointer to physdev_irq_status_query structure.
 177   */