xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Dario Faggioli <dario.faggioli@citrix.com>
To: xen-devel@lists.xenproject.org
Cc: George Dunlap <george.dunlap@eu.citrix.com>,
	Tianyang Chen <tiche@seas.upenn.edu>,
	Meng Xu <mengxu@cis.upenn.edu>
Subject: [PATCH 08/16] xen: sched: prepare a .switch_sched hook for Credit2
Date: Fri, 18 Mar 2016 20:04:57 +0100	[thread overview]
Message-ID: <20160318190457.8117.88084.stgit@Solace.station> (raw)
In-Reply-To: <20160318185524.8117.74837.stgit@Solace.station>

RTDS is basically identical to Credit2, as far as scheduler
lock (re)mapping is concerned. Therefore, the same analisys
and considerations expressed for the previous patch ("xen:
sched: prepare a .switch_sched hook for Credit2"), applies
to it to.

This patch, therefore, introduces the switch_sched hook
for RTDS, as done already for Credit2 and Credit1.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
---
Cc: George Dunlap <george.dunlap@eu.citrix.com>
Cc: Meng Xu <mengxu@cis.upenn.edu>
Cc: Tianyang Chen <tiche@seas.upenn.edu>
---
 xen/common/sched_rt.c |   31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/xen/common/sched_rt.c b/xen/common/sched_rt.c
index b6ac3ad..92be248 100644
--- a/xen/common/sched_rt.c
+++ b/xen/common/sched_rt.c
@@ -665,6 +665,36 @@ rt_init_pdata(const struct scheduler *ops, void *pdata, int cpu)
     spin_unlock_irqrestore(old_lock, flags);
 }
 
+/* Change the scheduler of cpu to us (RTDS). */
+static void
+rt_switch_sched(struct scheduler *new_ops, unsigned int cpu,
+                void *pdata, void *vdata)
+{
+    struct rt_vcpu *svc = vdata;
+    spinlock_t *old_lock;
+
+    ASSERT(!pdata && svc && is_idle_vcpu(svc->vcpu));
+
+    /*
+     * We may be acquiring the lock of another scheduler here (the one cpu
+     * still belongs to when calling this function). That is ok as, anyone
+     * trying to schedule on this cpu will block until when we release that
+     * lock (bottom of this function). When unblocked --because of the loop
+     * implemented by schedule_lock() functions-- he will notice the lock
+     * changed, and acquire ours before being able to proceed.
+     */
+    old_lock = pcpu_schedule_lock_irq(cpu);
+
+    idle_vcpu[cpu]->sched_priv = vdata;
+    per_cpu(scheduler, cpu) = new_ops;
+    per_cpu(schedule_data, cpu).sched_priv = NULL; /* no pdata */
+    /* (Re?)route the lock to our global lock. */
+    per_cpu(schedule_data, cpu).schedule_lock = &rt_priv(new_ops)->lock;
+
+    /* _Not_ pcpu_schedule_unlock(): schedule_lock may have changed! */
+    spin_unlock_irq(old_lock);
+}
+
 static void *
 rt_alloc_pdata(const struct scheduler *ops, int cpu)
 {
@@ -1400,6 +1430,7 @@ static const struct scheduler sched_rtds_def = {
     .alloc_pdata    = rt_alloc_pdata,
     .free_pdata     = rt_free_pdata,
     .init_pdata     = rt_init_pdata,
+    .switch_sched   = rt_switch_sched,
     .alloc_domdata  = rt_alloc_domdata,
     .free_domdata   = rt_free_domdata,
     .init_domain    = rt_dom_init,


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

  parent reply	other threads:[~2016-03-18 19:05 UTC|newest]

Thread overview: 61+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-18 19:03 [PATCH 00/16] Fixes and improvement (including hard affinity!) " Dario Faggioli
2016-03-18 19:04 ` [PATCH 01/16] xen: sched: fix locking when allocating an RTDS pCPU Dario Faggioli
2016-03-19  2:22   ` Meng Xu
2016-03-23 15:37   ` George Dunlap
2016-03-18 19:04 ` [PATCH 02/16] xen: sched: add .init_pdata hook to the scheduler interface Dario Faggioli
2016-03-22  8:08   ` Juergen Gross
2016-03-23 17:32   ` George Dunlap
2016-03-18 19:04 ` [PATCH 03/16] xen: sched: make implementing .alloc_pdata optional Dario Faggioli
2016-03-19  2:23   ` Meng Xu
2016-03-21 14:22   ` Jan Beulich
2016-03-23 17:36     ` George Dunlap
2016-03-24  9:43       ` Jan Beulich
2016-03-24 13:14         ` Dario Faggioli
2016-03-21 14:48   ` Juergen Gross
2016-03-21 15:07     ` Jan Beulich
2016-04-01 17:01       ` Dario Faggioli
2016-04-04  4:21         ` Juergen Gross
2016-04-04  6:13         ` Jan Beulich
2016-04-05 16:01           ` Dario Faggioli
2016-03-23 17:38   ` George Dunlap
2016-03-18 19:04 ` [PATCH 04/16] xen: sched: implement .init_pdata in all schedulers Dario Faggioli
2016-03-19  2:24   ` Meng Xu
2016-03-22  8:03   ` Juergen Gross
2016-03-23 17:46     ` George Dunlap
2016-03-18 19:04 ` [PATCH 05/16] xen: sched: move pCPU initialization in an helper Dario Faggioli
2016-03-23 17:51   ` George Dunlap
2016-03-23 18:09     ` George Dunlap
2016-03-24 13:21     ` Dario Faggioli
2016-03-18 19:04 ` [PATCH 06/16] xen: sched: prepare a .switch_sched hook for Credit1 Dario Faggioli
2016-03-18 19:04 ` [PATCH 07/16] xen: sched: prepare a .switch_sched hook for Credit2 Dario Faggioli
2016-03-18 19:04 ` Dario Faggioli [this message]
2016-03-19  2:24   ` [PATCH 08/16] " Meng Xu
2016-03-21 14:25   ` Jan Beulich
2016-03-18 19:05 ` [PATCH 09/16] xen: sched: close potential races when switching scheduler to CPUs Dario Faggioli
2016-03-19  2:25   ` Meng Xu
2016-03-23 19:05   ` George Dunlap
2016-04-05 16:26     ` Dario Faggioli
2016-04-06 15:51       ` Dario Faggioli
2016-03-24 12:14   ` George Dunlap
2016-04-05 17:37     ` Dario Faggioli
2016-04-06 16:21       ` Dario Faggioli
2016-03-18 19:05 ` [PATCH 10/16] xen: sched: improve credit2 bootparams' scope, placement and signedness Dario Faggioli
2016-03-21 14:51   ` Juergen Gross
2016-03-24 12:20   ` George Dunlap
2016-03-18 19:05 ` [PATCH 11/16] xen: sched: on Credit2, don't reprogram the timer if idle Dario Faggioli
2016-03-24 15:03   ` George Dunlap
2016-03-18 19:05 ` [PATCH 12/16] xen: sched: fix per-socket runqueue creation in credit2 Dario Faggioli
2016-03-24 12:24   ` George Dunlap
2016-03-18 19:05 ` [PATCH 13/16] xen: sched: allow for choosing credit2 runqueues configuration at boot Dario Faggioli
2016-03-22  7:46   ` Juergen Gross
2016-03-24 12:36   ` George Dunlap
2016-03-18 19:05 ` [PATCH 14/16] xen: sched: per-core runqueues as default in credit2 Dario Faggioli
2016-03-24 12:37   ` George Dunlap
2016-03-18 19:06 ` [PATCH 15/16] xen: sched: scratch space for cpumasks on Credit2 Dario Faggioli
2016-03-18 19:27   ` Andrew Cooper
2016-03-24 12:44     ` George Dunlap
2016-03-24 12:56       ` Andrew Cooper
2016-03-24 13:10       ` Dario Faggioli
2016-03-18 19:06 ` [PATCH 16/16] xen: sched: implement vcpu hard affinity in Credit2 Dario Faggioli
2016-03-24 15:42   ` George Dunlap
2016-04-05 16:50     ` Dario Faggioli

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20160318190457.8117.88084.stgit@Solace.station \
    --to=dario.faggioli@citrix.com \
    --cc=george.dunlap@eu.citrix.com \
    --cc=mengxu@cis.upenn.edu \
    --cc=tiche@seas.upenn.edu \
    --cc=xen-devel@lists.xenproject.org \
    --subject='Re: [PATCH 08/16] xen: sched: prepare a .switch_sched hook for Credit2' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
on how to clone and mirror all data and code used for this inbox