[42/60] xen/sched: add a scheduler_percpu_init() function

Commit Message

Jürgen Groß May 28, 2019, 10:32 a.m. UTC

For support of core scheduling the scheduler cpu callback for
CPU_STARTING has to be moved into a dedicated function called by
start_secondary() as it needs to run before spin_debug_enable() then
due to potentially calling xfree().

Signed-off-by: Juergen Gross <[e-mail]>
---
RFC V2: fix ARM build
---
 xen/arch/arm/smpboot.c  |  2 ++
 xen/arch/x86/smpboot.c  |  2 ++
 xen/common/schedule.c   | 19 ++++++++++++-------
 xen/include/xen/sched.h |  1 +
 4 files changed, 17 insertions(+), 7 deletions(-)

Patch

diff --git a/xen/arch/arm/smpboot.c b/xen/arch/arm/smpboot.c
index f756444362..9a6582f2a6 100644
--- a/xen/arch/arm/smpboot.c
+++ b/xen/arch/arm/smpboot.c
@@ -350,6 +350,8 @@  void start_secondary(unsigned long boot_phys_offset,
 
     setup_cpu_sibling_map(cpuid);
 
+    scheduler_percpu_init(cpuid);
+
     /* Run local notifiers */
     notify_cpu_starting(cpuid);
     /*
diff --git a/xen/arch/x86/smpboot.c b/xen/arch/x86/smpboot.c
index 153bfbb4b7..7e95b2cdac 100644
--- a/xen/arch/x86/smpboot.c
+++ b/xen/arch/x86/smpboot.c
@@ -382,6 +382,8 @@  void start_secondary(void *unused)
 
     set_cpu_sibling_map(cpu);
 
+    scheduler_percpu_init(cpu);
+
     init_percpu_time();
 
     setup_secondary_APIC_clock();
diff --git a/xen/common/schedule.c b/xen/common/schedule.c
index 837e183004..b4e87e2a58 100644
--- a/xen/common/schedule.c
+++ b/xen/common/schedule.c
@@ -2040,6 +2040,15 @@  static void cpu_schedule_down(unsigned int cpu)
     xfree(sd);
 }
 
+void scheduler_percpu_init(unsigned int cpu)
+{
+    struct scheduler *sched = per_cpu(scheduler, cpu);
+    struct sched_resource *sd = get_sched_res(cpu);
+
+    if ( system_state != SYS_STATE_resume )
+        sched_init_pdata(sched, sd->sched_priv, cpu);
+}
+
 static int cpu_schedule_callback(
     struct notifier_block *nfb, unsigned long action, void *hcpu)
 {
@@ -2058,8 +2067,8 @@  static int cpu_schedule_callback(
      * data can avoid implementing alloc_pdata. init_pdata may, however, be
      * necessary/useful in this case too (e.g., it can contain the "register
      * the pCPU to the scheduler" part). alloc_pdata (if present) is called
-     * during CPU_UP_PREPARE. init_pdata (if present) is called during
-     * CPU_STARTING.
+     * during CPU_UP_PREPARE. init_pdata (if present) is called before
+     * CPU_STARTING in scheduler_percpu_init().
      *
      * On the other hand, at teardown, we need to reverse what has been done
      * during initialization, and then free the per-pCPU specific data. This
@@ -2082,10 +2091,6 @@  static int cpu_schedule_callback(
      */
     switch ( action )
     {
-    case CPU_STARTING:
-        if ( system_state != SYS_STATE_resume )
-            sched_init_pdata(sched, sd->sched_priv, cpu);
-        break;
     case CPU_UP_PREPARE:
         if ( system_state != SYS_STATE_resume )
             rc = cpu_schedule_up(cpu);
@@ -2206,7 +2211,7 @@  void __init scheduler_init(void)
     get_sched_res(0)->curr = idle_vcpu[0]->sched_unit;
     get_sched_res(0)->sched_priv = sched_alloc_pdata(&ops, 0);
     BUG_ON(IS_ERR(get_sched_res(0)->sched_priv));
-    sched_init_pdata(&ops, get_sched_res(0)->sched_priv, 0);
+    scheduler_percpu_init(0);
 }
 
 /*
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index d5bf61ced0..af4c934e0b 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -675,6 +675,7 @@  void __domain_crash(struct domain *d);
 void noreturn asm_domain_crash_synchronous(unsigned long addr);
 
 void scheduler_init(void);
+void scheduler_percpu_init(unsigned int cpu);
 int  sched_init_vcpu(struct vcpu *v);
 void sched_destroy_vcpu(struct vcpu *v);
 int  sched_init_domain(struct domain *d, int poolid);