WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-changelog

[Xen-changelog] [xen-unstable] ARINC 653 scheduler

To: xen-changelog@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-changelog] [xen-unstable] ARINC 653 scheduler
From: Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>
Date: Tue, 07 Dec 2010 10:10:33 -0800
Delivery-date: Tue, 07 Dec 2010 10:14:45 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-changelog-request@lists.xensource.com?subject=help>
List-id: BK change log <xen-changelog.lists.xensource.com>
List-post: <mailto:xen-changelog@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=unsubscribe>
Reply-to: xen-devel@xxxxxxxxxxxxxxxxxxx
Sender: xen-changelog-bounces@xxxxxxxxxxxxxxxxxxx
# HG changeset patch
# User Keir Fraser <keir@xxxxxxx>
# Date 1291238414 0
# Node ID c443d02158542a9509f2521089ad6f29e290e6df
# Parent  c2cb776a5365bd3891174e7375d9079a76b37008
ARINC 653 scheduler
From: Josh Holtrop <Josh.Holtrop@xxxxxxxxxxxxxxx>
Signed-off-by: Keir Fraser <keir@xxxxxxx>
Acked-by: George Dunlap <george.dunlap@xxxxxxxxxxxxx>
---
 tools/libxc/Makefile        |    1 
 tools/libxc/xc_arinc653.c   |   85 +++++
 tools/libxc/xenctrl.h       |   10 
 xen/common/Makefile         |    1 
 xen/common/sched_arinc653.c |  698 ++++++++++++++++++++++++++++++++++++++++++++
 xen/common/schedule.c       |    2 
 xen/include/public/domctl.h |    1 
 xen/include/public/sysctl.h |   31 +
 8 files changed, 829 insertions(+)

diff -r c2cb776a5365 -r c443d0215854 tools/libxc/Makefile
--- a/tools/libxc/Makefile      Wed Dec 01 20:12:12 2010 +0000
+++ b/tools/libxc/Makefile      Wed Dec 01 21:20:14 2010 +0000
@@ -19,6 +19,7 @@ CTRL_SRCS-y       += xc_sedf.c
 CTRL_SRCS-y       += xc_sedf.c
 CTRL_SRCS-y       += xc_csched.c
 CTRL_SRCS-y       += xc_csched2.c
+CTRL_SRCS-y       += xc_arinc653.c
 CTRL_SRCS-y       += xc_tbuf.c
 CTRL_SRCS-y       += xc_pm.c
 CTRL_SRCS-y       += xc_cpu_hotplug.c
diff -r c2cb776a5365 -r c443d0215854 tools/libxc/xc_arinc653.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/tools/libxc/xc_arinc653.c Wed Dec 01 21:20:14 2010 +0000
@@ -0,0 +1,85 @@
+/******************************************************************************
+ * xc_arinc653.c
+ * 
+ * XC interface to the ARINC653 scheduler
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (c) 2010 DornerWorks, Ltd. <DornerWorks.com>
+ */
+
+#include "xc_private.h"
+
+int
+xc_sched_arinc653_schedule_set(
+    xc_interface *xch,
+    struct xen_sysctl_arinc653_schedule *schedule)
+{
+    int rc;
+    DECLARE_SYSCTL;
+    DECLARE_HYPERCALL_BOUNCE(
+        schedule,
+        sizeof(*schedule),
+        XC_HYPERCALL_BUFFER_BOUNCE_IN);
+
+    if ( xc_hypercall_bounce_pre(xch, schedule) )
+        return -1;
+
+    sysctl.cmd = XEN_SYSCTL_scheduler_op;
+    sysctl.u.scheduler_op.cpupool_id = 0;
+    sysctl.u.scheduler_op.sched_id = XEN_SCHEDULER_ARINC653;
+    sysctl.u.scheduler_op.cmd = XEN_SYSCTL_SCHEDOP_putinfo;
+    set_xen_guest_handle(sysctl.u.scheduler_op.u.sched_arinc653.schedule,
+            schedule);
+
+    rc = do_sysctl(xch, &sysctl);
+
+    xc_hypercall_bounce_post(xch, schedule);
+
+    return rc;
+}
+
+int
+xc_sched_arinc653_schedule_get(
+    xc_interface *xch,
+    struct xen_sysctl_arinc653_schedule *schedule)
+{
+    int rc;
+    DECLARE_SYSCTL;
+    DECLARE_HYPERCALL_BOUNCE(
+        schedule,
+        sizeof(*schedule),
+        XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+
+    if ( xc_hypercall_bounce_pre(xch, schedule) )
+        return -1;
+
+    sysctl.cmd = XEN_SYSCTL_scheduler_op;
+    sysctl.u.scheduler_op.cpupool_id = 0;
+    sysctl.u.scheduler_op.sched_id = XEN_SCHEDULER_ARINC653;
+    sysctl.u.scheduler_op.cmd = XEN_SYSCTL_SCHEDOP_getinfo;
+    set_xen_guest_handle(sysctl.u.scheduler_op.u.sched_arinc653.schedule,
+            schedule);
+
+    rc = do_sysctl(xch, &sysctl);
+
+    xc_hypercall_bounce_post(xch, schedule);
+
+    return rc;
+}
diff -r c2cb776a5365 -r c443d0215854 tools/libxc/xenctrl.h
--- a/tools/libxc/xenctrl.h     Wed Dec 01 20:12:12 2010 +0000
+++ b/tools/libxc/xenctrl.h     Wed Dec 01 21:20:14 2010 +0000
@@ -644,6 +644,16 @@ int xc_sched_credit2_domain_get(xc_inter
 int xc_sched_credit2_domain_get(xc_interface *xch,
                                uint32_t domid,
                                struct xen_domctl_sched_credit2 *sdom);
+
+int
+xc_sched_arinc653_schedule_set(
+    xc_interface *xch,
+    struct xen_sysctl_arinc653_schedule *schedule);
+
+int
+xc_sched_arinc653_schedule_get(
+    xc_interface *xch,
+    struct xen_sysctl_arinc653_schedule *schedule);
 
 /**
  * This function sends a trigger to a domain.
diff -r c2cb776a5365 -r c443d0215854 xen/common/Makefile
--- a/xen/common/Makefile       Wed Dec 01 20:12:12 2010 +0000
+++ b/xen/common/Makefile       Wed Dec 01 21:20:14 2010 +0000
@@ -18,6 +18,7 @@ obj-y += sched_credit.o
 obj-y += sched_credit.o
 obj-y += sched_credit2.o
 obj-y += sched_sedf.o
+obj-y += sched_arinc653.o
 obj-y += schedule.o
 obj-y += shutdown.o
 obj-y += softirq.o
diff -r c2cb776a5365 -r c443d0215854 xen/common/sched_arinc653.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/xen/common/sched_arinc653.c       Wed Dec 01 21:20:14 2010 +0000
@@ -0,0 +1,698 @@
+/******************************************************************************
+ * sched_arinc653.c
+ *
+ * An ARINC653-compatible scheduling algorithm for use in Xen.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (c) 2010, DornerWorks, Ltd. <DornerWorks.com>
+ */
+
+#include <xen/config.h>
+#include <xen/lib.h>
+#include <xen/sched.h>
+#include <xen/sched-if.h>
+#include <xen/timer.h>
+#include <xen/softirq.h>
+#include <xen/time.h>
+#include <xen/errno.h>
+#include <xen/list.h>
+#include <xen/guest_access.h>
+#include <public/sysctl.h>
+
+/**************************************************************************
+ * Private Macros                                                         *
+ **************************************************************************/
+
+/** 
+ * Retrieve the idle VCPU for a given physical CPU 
+ */ 
+#define IDLETASK(cpu)  (idle_vcpu[cpu])
+
+/**
+ * Return a pointer to the ARINC 653-specific scheduler data information
+ * associated with the given VCPU (vc)
+ */
+#define AVCPU(vc) ((arinc653_vcpu_t *)(vc)->sched_priv)
+
+/**
+ * Return the global scheduler private data given the scheduler ops pointer
+ */
+#define SCHED_PRIV(s) ((a653sched_priv_t *)((s)->sched_data))
+
+/**************************************************************************
+ * Private Type Definitions                                               *
+ **************************************************************************/
+
+/**
+ * The arinc653_vcpu_t structure holds ARINC 653-scheduler-specific
+ * information for all non-idle VCPUs
+ */
+typedef struct arinc653_vcpu_s
+{
+    /* vc points to Xen's struct vcpu so we can get to it from an
+     * arinc653_vcpu_t pointer. */
+    struct vcpu *       vc;
+    /* awake holds whether the VCPU has been woken with vcpu_wake() */
+    bool_t              awake;
+    /* list holds the linked list information for the list this VCPU
+     * is stored in */
+    struct list_head    list;
+} arinc653_vcpu_t;
+
+/**  
+ * The sched_entry_t structure holds a single entry of the
+ * ARINC 653 schedule.
+ */
+typedef struct sched_entry_s
+{
+    /* dom_handle holds the handle ("UUID") for the domain that this
+     * schedule entry refers to. */
+    xen_domain_handle_t dom_handle;
+    /* vcpu_id holds the VCPU number for the VCPU that this schedule
+     * entry refers to. */
+    int                 vcpu_id;
+    /* runtime holds the number of nanoseconds that the VCPU for this
+     * schedule entry should be allowed to run per major frame. */
+    s_time_t            runtime;
+    /* vc holds a pointer to the Xen VCPU structure */
+    struct vcpu *       vc;
+} sched_entry_t;
+
+/**
+ * This structure defines data that is global to an instance of the scheduler
+ */
+typedef struct a653sched_priv_s
+{
+    /**
+     * This array holds the active ARINC 653 schedule. 
+     *  
+     * When the system tries to start a new VCPU, this schedule is scanned
+     * to look for a matching (handle, VCPU #) pair. If both the handle (UUID)
+     * and VCPU number match, then the VCPU is allowed to run. Its run time
+     * (per major frame) is given in the third entry of the schedule.
+     */
+    sched_entry_t schedule[ARINC653_MAX_DOMAINS_PER_SCHEDULE];
+
+    /**
+     * This variable holds the number of entries that are valid in
+     * the arinc653_schedule table. 
+     *  
+     * This is not necessarily the same as the number of domains in the
+     * schedule. A domain could be listed multiple times within the schedule,
+     * or a domain with multiple VCPUs could have a different
+     * schedule entry for each VCPU. 
+     */
+    int num_schedule_entries;
+
+    /**
+     * the major frame time for the ARINC 653 schedule.
+     */
+    s_time_t major_frame;
+
+    /**
+     * the time that the next major frame starts
+     */
+    s_time_t next_major_frame;
+
+    /** 
+     * pointers to all Xen VCPU structures for iterating through 
+     */ 
+    struct list_head vcpu_list;
+} a653sched_priv_t;
+
+/**************************************************************************
+ * Helper functions                                                       *
+ **************************************************************************/
+
+/**
+ * This function compares two domain handles.
+ * 
+ * @param h1        Pointer to handle 1
+ * @param h2        Pointer to handle 2
+ * 
+ * @return          <ul>
+ *                  <li> <0:  handle 1 is less than handle 2   
+ *                  <li>  0:  handle 1 is equal to handle 2    
+ *                  <li> >0:  handle 1 is greater than handle 2 
+ *                  </ul>
+ */
+static int dom_handle_cmp(const xen_domain_handle_t h1,
+                          const xen_domain_handle_t h2)
+{
+    return memcmp(h1, h2, sizeof(xen_domain_handle_t));
+}
+
+/**
+ * This function searches the vcpu list to find a VCPU that matches
+ * the domain handle and VCPU ID specified.
+ * 
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @param handle    Pointer to handler
+ * @param vcpu_id   VCPU ID
+ * 
+ * @return          <ul>
+ *                  <li> Pointer to the matching VCPU if one is found
+ *                  <li> NULL otherwise
+ *                  </ul>
+ */
+static struct vcpu *find_vcpu(
+    const struct scheduler *ops,
+    xen_domain_handle_t handle,
+    int vcpu_id)
+{
+    arinc653_vcpu_t *avcpu;
+
+    /* loop through the vcpu_list looking for the specified VCPU */
+    list_for_each_entry ( avcpu, &SCHED_PRIV(ops)->vcpu_list, list )
+        if ( (dom_handle_cmp(avcpu->vc->domain->handle, handle) == 0)
+             && (vcpu_id == avcpu->vc->vcpu_id) )
+            return avcpu->vc;
+
+    return NULL;
+}
+
+/**
+ * This function updates the pointer to the Xen VCPU structure for each entry
+ * in the ARINC 653 schedule.
+ * 
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @return          <None>
+ */
+static void update_schedule_vcpus(const struct scheduler *ops)
+{
+    unsigned int i, n_entries = SCHED_PRIV(ops)->num_schedule_entries;
+
+    for ( i = 0; i < n_entries; i++ )
+        SCHED_PRIV(ops)->schedule[i].vc =
+            find_vcpu(ops,
+                      SCHED_PRIV(ops)->schedule[i].dom_handle,
+                      SCHED_PRIV(ops)->schedule[i].vcpu_id);
+}
+
+/**
+ * This function is called by the adjust_global scheduler hook to put
+ * in place a new ARINC653 schedule.
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ * 
+ * @return          <ul>
+ *                  <li> 0 = success
+ *                  <li> !0 = error
+ *                  </ul>
+ */
+static int
+arinc653_sched_set(
+    const struct scheduler *ops,
+    struct xen_sysctl_arinc653_schedule *schedule)
+{
+    a653sched_priv_t *sched_priv = SCHED_PRIV(ops);
+    s_time_t total_runtime = 0;
+    bool_t found_dom0 = 0;
+    const static xen_domain_handle_t dom0_handle = {0};
+    unsigned int i;
+
+    /* Check for valid major frame and number of schedule entries. */
+    if ( (schedule->major_frame <= 0)
+         || (schedule->num_sched_entries < 1)
+         || (schedule->num_sched_entries > ARINC653_MAX_DOMAINS_PER_SCHEDULE) )
+        goto fail;
+
+    for ( i = 0; i < schedule->num_sched_entries; i++ )
+    {
+        if ( dom_handle_cmp(schedule->sched_entries[i].dom_handle,
+                            dom0_handle) == 0 )
+            found_dom0 = 1;
+
+        /* Check for a valid VCPU ID and run time. */
+        if ( (schedule->sched_entries[i].vcpu_id < 0)
+             || (schedule->sched_entries[i].runtime <= 0) )
+            goto fail;
+
+        /* Add this entry's run time to total run time. */
+        total_runtime += schedule->sched_entries[i].runtime;
+    }
+
+    /* Error if the schedule doesn't contain a slot for domain 0. */
+    if ( !found_dom0 )
+        goto fail;
+
+    /* 
+     * Error if the major frame is not large enough to run all entries as
+     * indicated by comparing the total run time to the major frame length.
+     */ 
+    if ( total_runtime > schedule->major_frame )
+        goto fail;
+
+    /* Copy the new schedule into place. */
+    sched_priv->num_schedule_entries = schedule->num_sched_entries;
+    sched_priv->major_frame = schedule->major_frame;
+    for ( i = 0; i < schedule->num_sched_entries; i++ )
+    {
+        memcpy(sched_priv->schedule[i].dom_handle,
+               schedule->sched_entries[i].dom_handle,
+               sizeof(sched_priv->schedule[i].dom_handle));
+        sched_priv->schedule[i].vcpu_id =
+            schedule->sched_entries[i].vcpu_id;
+        sched_priv->schedule[i].runtime =
+            schedule->sched_entries[i].runtime;
+    }
+    update_schedule_vcpus(ops);
+
+    /*
+     * The newly-installed schedule takes effect immediately. We do not even 
+     * wait for the current major frame to expire.
+     *
+     * Signal a new major frame to begin. The next major frame is set up by 
+     * the do_schedule callback function when it is next invoked.
+     */
+    sched_priv->next_major_frame = NOW();
+
+    return 0;
+
+ fail:
+    return -EINVAL;
+}
+
+/**
+ * This function is called by the adjust_global scheduler hook to read the
+ * current ARINC 653 schedule
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @return          <ul>
+ *                  <li> 0 = success
+ *                  <li> !0 = error
+ *                  </ul>
+ */
+static int
+arinc653_sched_get(
+    const struct scheduler *ops,
+    struct xen_sysctl_arinc653_schedule *schedule)
+{
+    a653sched_priv_t *sched_priv = SCHED_PRIV(ops);
+    unsigned int i;
+
+    schedule->num_sched_entries = sched_priv->num_schedule_entries;
+    schedule->major_frame = sched_priv->major_frame;
+    for ( i = 0; i < sched_priv->num_schedule_entries; i++ )
+    {
+        memcpy(schedule->sched_entries[i].dom_handle,
+               sched_priv->schedule[i].dom_handle,
+               sizeof(sched_priv->schedule[i].dom_handle));
+        schedule->sched_entries[i].vcpu_id = sched_priv->schedule[i].vcpu_id;
+        schedule->sched_entries[i].runtime = sched_priv->schedule[i].runtime;
+    }
+
+    return 0;
+}
+
+/**************************************************************************
+ * Scheduler callback functions                                           *
+ **************************************************************************/
+
+/**
+ * This function performs initialization for an instance of the scheduler.
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ *
+ * @return          <ul>
+ *                  <li> 0 = success
+ *                  <li> !0 = error
+ *                  </ul>
+ */
+static int
+a653sched_init(struct scheduler *ops)
+{
+    a653sched_priv_t *prv;
+
+    prv = xmalloc(a653sched_priv_t);
+    if ( prv == NULL )
+        return -ENOMEM;
+
+    memset(prv, 0, sizeof(*prv));
+    ops->sched_data = prv;
+
+    prv->schedule[0].dom_handle[0] = '\0';
+    prv->schedule[0].vcpu_id = 0;
+    prv->schedule[0].runtime = MILLISECS(10);
+    prv->schedule[0].vc = NULL;
+    prv->num_schedule_entries = 1;
+    prv->major_frame = MILLISECS(10);
+    prv->next_major_frame = 0;
+    INIT_LIST_HEAD(&prv->vcpu_list);
+
+    return 0;
+}
+
+/**
+ * This function performs deinitialization for an instance of the scheduler
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ */
+static void
+a653sched_deinit(const struct scheduler *ops)
+{
+    xfree(SCHED_PRIV(ops));
+}
+
+/**
+ * This function allocates scheduler-specific data for a VCPU
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ *
+ * @return          Pointer to the allocated data
+ */
+static void *
+a653sched_alloc_vdata(const struct scheduler *ops, struct vcpu *vc, void *dd)
+{
+    /* 
+     * Allocate memory for the ARINC 653-specific scheduler data information
+     * associated with the given VCPU (vc). 
+     */ 
+    if ( (vc->sched_priv = xmalloc(arinc653_vcpu_t)) == NULL )
+        return NULL;
+
+    /*
+     * Initialize our ARINC 653 scheduler-specific information for the VCPU.
+     * The VCPU starts "asleep." When Xen is ready for the VCPU to run, it 
+     * will call the vcpu_wake scheduler callback function and our scheduler 
+     * will mark the VCPU awake.
+     */
+    AVCPU(vc)->vc = vc;
+    AVCPU(vc)->awake = 0;
+    if ( !is_idle_vcpu(vc) )
+        list_add(&AVCPU(vc)->list, &SCHED_PRIV(ops)->vcpu_list);
+    update_schedule_vcpus(ops);
+
+    return AVCPU(vc);
+}
+
+/**
+ * This function frees scheduler-specific VCPU data
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ */
+static void
+a653sched_free_vdata(const struct scheduler *ops, void *priv)
+{
+    arinc653_vcpu_t *av = priv;
+
+    if (av == NULL)
+        return;
+
+    list_del(&av->list);
+    xfree(av);
+    update_schedule_vcpus(ops);
+}
+
+/**
+ * This function allocates scheduler-specific data for a physical CPU
+ *
+ * We do not actually make use of any per-CPU data but the hypervisor expects
+ * a non-NULL return value
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ *
+ * @return          Pointer to the allocated data
+ */
+static void *
+a653sched_alloc_pdata(const struct scheduler *ops, int cpu)
+{
+    /* return a non-NULL value to keep schedule.c happy */
+    return SCHED_PRIV(ops);
+}
+
+/**
+ * This function frees scheduler-specific data for a physical CPU
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ */
+static void
+a653sched_free_pdata(const struct scheduler *ops, void *pcpu, int cpu)
+{
+    /* nop */
+}
+
+/**
+ * This function allocates scheduler-specific data for a domain
+ *
+ * We do not actually make use of any per-domain data but the hypervisor
+ * expects a non-NULL return value
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ *
+ * @return          Pointer to the allocated data
+ */
+static void *
+a653sched_alloc_domdata(const struct scheduler *ops, struct domain *dom)
+{
+    /* return a non-NULL value to keep schedule.c happy */
+    return SCHED_PRIV(ops);
+}
+
+/**
+ * This function frees scheduler-specific data for a domain
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ */
+static void
+a653sched_free_domdata(const struct scheduler *ops, void *data)
+{
+    /* nop */
+}
+
+/**
+ * Xen scheduler callback function to sleep a VCPU
+ * 
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @param vc        Pointer to the VCPU structure for the current domain
+ */
+static void
+a653sched_vcpu_sleep(const struct scheduler *ops, struct vcpu *vc)
+{
+    if ( AVCPU(vc) != NULL )
+        AVCPU(vc)->awake = 0;
+
+    /*
+     * If the VCPU being put to sleep is the same one that is currently
+     * running, raise a softirq to invoke the scheduler to switch domains.
+     */
+    if ( per_cpu(schedule_data, vc->processor).curr == vc )
+        cpu_raise_softirq(vc->processor, SCHEDULE_SOFTIRQ);
+}
+
+/**
+ * Xen scheduler callback function to wake up a VCPU
+ * 
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @param vc        Pointer to the VCPU structure for the current domain
+ */
+static void
+a653sched_vcpu_wake(const struct scheduler *ops, struct vcpu *vc)
+{
+    if ( AVCPU(vc) != NULL )
+        AVCPU(vc)->awake = 1;
+
+    cpu_raise_softirq(vc->processor, SCHEDULE_SOFTIRQ);
+}
+
+/**
+ * Xen scheduler callback function to select a VCPU to run.
+ * This is the main scheduler routine.
+ * 
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @param now       Current time
+ * 
+ * @return          Address of the VCPU structure scheduled to be run next
+ *                  Amount of time to execute the returned VCPU
+ *                  Flag for whether the VCPU was migrated
+ */
+static struct task_slice
+a653sched_do_schedule(
+    const struct scheduler *ops,
+    s_time_t now,
+    bool_t tasklet_work_scheduled)
+{
+    struct task_slice ret;                      /* hold the chosen domain */
+    struct vcpu * new_task = NULL;
+    static int sched_index = 0;
+    static s_time_t next_switch_time;
+    a653sched_priv_t *sched_priv = SCHED_PRIV(ops);
+
+    if ( now >= sched_priv->next_major_frame )
+    {
+        /* time to enter a new major frame
+         * the first time this function is called, this will be true */
+        /* start with the first domain in the schedule */
+        sched_index = 0;
+        sched_priv->next_major_frame = now + sched_priv->major_frame;
+        next_switch_time = now + sched_priv->schedule[0].runtime;
+    }
+    else
+    {
+        while ( (now >= next_switch_time)
+                && (sched_index < sched_priv->num_schedule_entries) )
+        {
+            /* time to switch to the next domain in this major frame */
+            sched_index++;
+            next_switch_time += sched_priv->schedule[sched_index].runtime;
+        }
+    }
+
+    /* 
+     * If we exhausted the domains in the schedule and still have time left
+     * in the major frame then switch next at the next major frame.
+     */
+    if ( sched_index >= sched_priv->num_schedule_entries )
+        next_switch_time = sched_priv->next_major_frame;
+
+    /*
+     * If there are more domains to run in the current major frame, set 
+     * new_task equal to the address of next domain's VCPU structure. 
+     * Otherwise, set new_task equal to the address of the idle task's VCPU 
+     * structure. 
+     */
+    new_task = (sched_index < sched_priv->num_schedule_entries)
+        ? sched_priv->schedule[sched_index].vc
+        : IDLETASK(0);
+
+    /* Check to see if the new task can be run (awake & runnable). */
+    if ( !((new_task != NULL)
+           && (AVCPU(new_task) != NULL)
+           && AVCPU(new_task)->awake
+           && vcpu_runnable(new_task)) )
+        new_task = IDLETASK(0);
+    BUG_ON(new_task == NULL);
+
+    /* 
+     * Check to make sure we did not miss a major frame.
+     * This is a good test for robust partitioning. 
+     */ 
+    BUG_ON(now >= sched_priv->next_major_frame);
+
+    /* Tasklet work (which runs in idle VCPU context) overrides all else. */
+    if ( tasklet_work_scheduled )
+        new_task = IDLETASK(0);
+
+    /*
+     * Return the amount of time the next domain has to run and the address 
+     * of the selected task's VCPU structure. 
+     */
+    ret.time = next_switch_time - now;
+    ret.task = new_task;
+    ret.migrated = 0;               /* we do not support migration */
+
+    BUG_ON(ret.time <= 0);
+
+    return ret;
+}
+
+/**
+ * Xen scheduler callback function to select a CPU for the VCPU to run on
+ * 
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @param v         Pointer to the VCPU structure for the current domain
+ * 
+ * @return          Number of selected physical CPU
+ */
+static int
+a653sched_pick_cpu(const struct scheduler *ops, struct vcpu *vc)
+{
+    /* this implementation only supports one physical CPU */
+    return 0;
+}
+
+/**
+ * Xen scheduler callback function to perform a global (not domain-specific)
+ * adjustment. It is used by the ARINC 653 scheduler to put in place a new
+ * ARINC 653 schedule or to retrieve the schedule currently in place.
+ *
+ * @param ops       Pointer to this instance of the scheduler structure
+ * @param sc        Pointer to the scheduler operation specified by Domain 0
+ */
+static int
+a653sched_adjust_global(const struct scheduler *ops,
+                        struct xen_sysctl_scheduler_op *sc)
+{
+    xen_sysctl_arinc653_schedule_t local_sched;
+    int rc = -EINVAL;
+
+    switch ( sc->cmd )
+    {
+    case XEN_SYSCTL_SCHEDOP_putinfo:
+        copy_from_guest(&local_sched, sc->u.sched_arinc653.schedule, 1);
+        rc = arinc653_sched_set(ops, &local_sched);
+        break;
+    case XEN_SYSCTL_SCHEDOP_getinfo:
+        rc = arinc653_sched_get(ops, &local_sched);
+        copy_to_guest(sc->u.sched_arinc653.schedule, &local_sched, 1);
+        break;
+    }
+
+    return rc;
+}
+
+/**
+ * This structure defines our scheduler for Xen.
+ * The entries tell Xen where to find our scheduler-specific
+ * callback functions.
+ * The symbol must be visible to the rest of Xen at link time.
+ */
+struct scheduler sched_arinc653_def = {
+    .name           = "ARINC 653 Scheduler",
+    .opt_name       = "arinc653",
+    .sched_id       = XEN_SCHEDULER_ARINC653,
+    .sched_data     = NULL,
+
+    .init           = a653sched_init,
+    .deinit         = a653sched_deinit,
+
+    .free_vdata     = a653sched_free_vdata,
+    .alloc_vdata    = a653sched_alloc_vdata,
+
+    .free_pdata     = a653sched_free_pdata,
+    .alloc_pdata    = a653sched_alloc_pdata,
+
+    .free_domdata   = a653sched_free_domdata,
+    .alloc_domdata  = a653sched_alloc_domdata,
+
+    .init_domain    = NULL,
+    .destroy_domain = NULL,
+
+    .insert_vcpu    = NULL,
+    .remove_vcpu    = NULL,
+
+    .sleep          = a653sched_vcpu_sleep,
+    .wake           = a653sched_vcpu_wake,
+    .yield          = NULL,
+    .context_saved  = NULL,
+
+    .do_schedule    = a653sched_do_schedule,
+
+    .pick_cpu       = a653sched_pick_cpu,
+
+    .adjust         = NULL,
+    .adjust_global  = a653sched_adjust_global,
+
+    .dump_settings  = NULL,
+    .dump_cpu_state = NULL,
+
+    .tick_suspend   = NULL,
+    .tick_resume    = NULL,
+};
diff -r c2cb776a5365 -r c443d0215854 xen/common/schedule.c
--- a/xen/common/schedule.c     Wed Dec 01 20:12:12 2010 +0000
+++ b/xen/common/schedule.c     Wed Dec 01 21:20:14 2010 +0000
@@ -60,10 +60,12 @@ extern const struct scheduler sched_sedf
 extern const struct scheduler sched_sedf_def;
 extern const struct scheduler sched_credit_def;
 extern const struct scheduler sched_credit2_def;
+extern const struct scheduler sched_arinc653_def;
 static const struct scheduler *schedulers[] = {
     &sched_sedf_def,
     &sched_credit_def,
     &sched_credit2_def,
+    &sched_arinc653_def,
     NULL
 };
 
diff -r c2cb776a5365 -r c443d0215854 xen/include/public/domctl.h
--- a/xen/include/public/domctl.h       Wed Dec 01 20:12:12 2010 +0000
+++ b/xen/include/public/domctl.h       Wed Dec 01 21:20:14 2010 +0000
@@ -300,6 +300,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_domctl_max_v
 #define XEN_SCHEDULER_SEDF     4
 #define XEN_SCHEDULER_CREDIT   5
 #define XEN_SCHEDULER_CREDIT2  6
+#define XEN_SCHEDULER_ARINC653 7
 /* Set or get info? */
 #define XEN_DOMCTL_SCHEDOP_putinfo 0
 #define XEN_DOMCTL_SCHEDOP_getinfo 1
diff -r c2cb776a5365 -r c443d0215854 xen/include/public/sysctl.h
--- a/xen/include/public/sysctl.h       Wed Dec 01 20:12:12 2010 +0000
+++ b/xen/include/public/sysctl.h       Wed Dec 01 21:20:14 2010 +0000
@@ -542,6 +542,34 @@ typedef struct xen_sysctl_cpupool_op xen
 typedef struct xen_sysctl_cpupool_op xen_sysctl_cpupool_op_t;
 DEFINE_XEN_GUEST_HANDLE(xen_sysctl_cpupool_op_t);
 
+#define ARINC653_MAX_DOMAINS_PER_SCHEDULE   64
+/*
+ * This structure is used to pass a new ARINC653 schedule from a
+ * privileged domain (ie dom0) to Xen.
+ */
+struct xen_sysctl_arinc653_schedule {
+    /* major_frame holds the time for the new schedule's major frame
+     * in nanoseconds. */
+    uint64_aligned_t     major_frame;
+    /* num_sched_entries holds how many of the entries in the
+     * sched_entries[] array are valid. */
+    uint8_t     num_sched_entries;
+    /* The sched_entries array holds the actual schedule entries. */
+    struct {
+        /* dom_handle must match a domain's UUID */
+        xen_domain_handle_t dom_handle;
+        /* If a domain has multiple VCPUs, vcpu_id specifies which one
+         * this schedule entry applies to. It should be set to 0 if
+         * there is only one VCPU for the domain. */
+        unsigned int vcpu_id;
+        /* runtime specifies the amount of time that should be allocated
+         * to this VCPU per major frame. It is specified in nanoseconds */
+        uint64_aligned_t runtime;
+    } sched_entries[ARINC653_MAX_DOMAINS_PER_SCHEDULE];
+};
+typedef struct xen_sysctl_arinc653_schedule xen_sysctl_arinc653_schedule_t;
+DEFINE_XEN_GUEST_HANDLE(xen_sysctl_arinc653_schedule_t);
+
 /* XEN_SYSCTL_scheduler_op */
 /* Set or get info? */
 #define XEN_SYSCTL_SCHEDOP_putinfo 0
@@ -551,6 +579,9 @@ struct xen_sysctl_scheduler_op {
     uint32_t sched_id;   /* XEN_SCHEDULER_* (domctl.h) */
     uint32_t cmd;        /* XEN_SYSCTL_SCHEDOP_* */
     union {
+        struct xen_sysctl_sched_arinc653 {
+            XEN_GUEST_HANDLE_64(xen_sysctl_arinc653_schedule_t) schedule;
+        } sched_arinc653;
     } u;
 };
 typedef struct xen_sysctl_scheduler_op xen_sysctl_scheduler_op_t;

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-changelog] [xen-unstable] ARINC 653 scheduler, Xen patchbot-unstable <=