[XEN PATCH v3] xen/sched: mechanical renaming to address MISRA C:2012 Rule 5.3

[Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>]

Rule 5.3 has the following headline:
"An identifier declared in an inner scope shall not hide an
identifier declared in an outer scope"

The renaming s/sched_id/scheduler_id/ of the function defined in
'xen/common/sched/core.c' prevents any hiding of that function
by the instances of homonymous function parameters that
are defined in inner scopes.

Similarly, the renames
- s/ops/operations/ for the static variable in 'xen/common/sched/core.c'
- s/do_softirq/needs_softirq/
are introduced for variables, to avoid any conflict with homonymous
parameters or function identifiers.

Moreover, the variable 'loop' defined at 'xen/common/sched/credit2.c:3887'
has been dropped, in favour of the homonymous variable declared in the
outer scope. This in turn requires a modification of the printk call that
involves it.

Signed-off-by: Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>
---
Changes in v3:
- removed stray changes to address the remarks
Changes in v2:
- s/softirq/needs_softirq/
- Dropped local variable 'it'
- Renamed the 'ops' static variable instead of function parameters
in the idle scheduler for coherence.

Note: local variable 'j' in xen/common/sched/credit2.c:3812' should
probably be unsigned as well, but I saw while editing the patch
that it's used as a parameter to 'dump_pcpu', which takes an int.
Possibly changing the types of parameters used in these calls is
probably a good target for another patch, as it's not relevant
w.r.t. Rule 5.3.
---
 xen/common/sched/core.c    | 28 ++++++++++++++--------------
 xen/common/sched/credit2.c |  6 +++---
 xen/common/sysctl.c        |  2 +-
 xen/include/xen/sched.h    |  2 +-
 4 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/xen/common/sched/core.c b/xen/common/sched/core.c
index 022f548652..12deefa745 100644
--- a/xen/common/sched/core.c
+++ b/xen/common/sched/core.c
@@ -91,7 +91,7 @@ extern const struct scheduler *__start_schedulers_array[], 
*__end_schedulers_arr
 #define NUM_SCHEDULERS (__end_schedulers_array - __start_schedulers_array)
 #define schedulers __start_schedulers_array

-static struct scheduler __read_mostly ops;
+static struct scheduler __read_mostly operations;

 static bool scheduler_active;

@@ -171,7 +171,7 @@ static inline struct scheduler *dom_scheduler(const struct 
domain *d)
      * is the default scheduler that has been, choosen at boot.
      */
     ASSERT(is_idle_domain(d));
-    return &ops;
+    return &operations;
 }

 static inline struct scheduler *unit_scheduler(const struct sched_unit *unit)
@@ -2040,10 +2040,10 @@ long do_set_timer_op(s_time_t timeout)
     return 0;
 }

-/* sched_id - fetch ID of current scheduler */
-int sched_id(void)
+/* scheduler_id - fetch ID of current scheduler */
+int scheduler_id(void)
 {
-    return ops.sched_id;
+    return operations.sched_id;
 }

 /* Adjust scheduling parameter for a given domain. */
@@ -2579,7 +2579,7 @@ static void cf_check sched_slave(void)
     struct sched_unit    *prev = vprev->sched_unit, *next;
     s_time_t              now;
     spinlock_t           *lock;
-    bool                  do_softirq = false;
+    bool                  needs_softirq = false;
     unsigned int          cpu = smp_processor_id();

     ASSERT_NOT_IN_ATOMIC();
@@ -2604,7 +2604,7 @@ static void cf_check sched_slave(void)
             return;
         }

-        do_softirq = true;
+        needs_softirq = true;
     }

     if ( !prev->rendezvous_in_cnt )
@@ -2614,7 +2614,7 @@ static void cf_check sched_slave(void)
         rcu_read_unlock(&sched_res_rculock);

         /* Check for failed forced context switch. */
-        if ( do_softirq )
+        if ( needs_softirq )
             raise_softirq(SCHEDULE_SOFTIRQ);

         return;
@@ -3016,14 +3016,14 @@ void __init scheduler_init(void)
         BUG_ON(!scheduler);
         printk("Using '%s' (%s)\n", scheduler->name, scheduler->opt_name);
     }
-    ops = *scheduler;
+    operations = *scheduler;

     if ( cpu_schedule_up(0) )
         BUG();
     register_cpu_notifier(&cpu_schedule_nfb);

-    printk("Using scheduler: %s (%s)\n", ops.name, ops.opt_name);
-    if ( sched_init(&ops) )
+    printk("Using scheduler: %s (%s)\n", operations.name, operations.opt_name);
+    if ( sched_init(&operations) )
         panic("scheduler returned error on init\n");

     if ( sched_ratelimit_us &&
@@ -3363,7 +3363,7 @@ int schedule_cpu_rm(unsigned int cpu, struct cpu_rm_data 
*data)

 struct scheduler *scheduler_get_default(void)
 {
-    return &ops;
+    return &operations;
 }

 struct scheduler *scheduler_alloc(unsigned int sched_id)
@@ -3392,7 +3392,7 @@ struct scheduler *scheduler_alloc(unsigned int sched_id)

 void scheduler_free(struct scheduler *sched)
 {
-    BUG_ON(sched == &ops);
+    BUG_ON(sched == &operations);
     sched_deinit(sched);
     xfree(sched);
 }
@@ -3416,7 +3416,7 @@ void schedule_dump(struct cpupool *c)
     }
     else
     {
-        sched = &ops;
+        sched = &operations;
         cpus = &cpupool_free_cpus;
     }

diff --git a/xen/common/sched/credit2.c b/xen/common/sched/credit2.c
index 87a1e31ee9..fc583915df 100644
--- a/xen/common/sched/credit2.c
+++ b/xen/common/sched/credit2.c
@@ -3874,7 +3874,7 @@ csched2_dump(const struct scheduler *ops)

             lock = unit_schedule_lock(unit);

-            printk("\t%3d: ", ++loop);
+            printk("\t%3u: ", ++loop);
             csched2_dump_unit(prv, svc);

             unit_schedule_unlock(lock, unit);
@@ -3884,8 +3884,8 @@ csched2_dump(const struct scheduler *ops)
     list_for_each_entry ( rqd, &prv->rql, rql )
     {
         struct list_head *iter, *runq = &rqd->runq;
-        int loop = 0;

+        loop = 0;
         /* We need the lock to scan the runqueue. */
         spin_lock(&rqd->lock);

@@ -3901,7 +3901,7 @@ csched2_dump(const struct scheduler *ops)

             if ( svc )
             {
-                printk("\t%3d: ", loop++);
+                printk("\t%3u: ", loop++);
                 csched2_dump_unit(prv, svc);
             }
         }
diff --git a/xen/common/sysctl.c b/xen/common/sysctl.c
index 0cbfe8bd44..7cabfb0230 100644
--- a/xen/common/sysctl.c
+++ b/xen/common/sysctl.c
@@ -71,7 +71,7 @@ long do_sysctl(XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
         break;

     case XEN_SYSCTL_sched_id:
-        op->u.sched_id.sched_id = sched_id();
+        op->u.sched_id.sched_id = scheduler_id();
         break;

     case XEN_SYSCTL_getdomaininfolist:
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index 854f3e32c0..bfe714d2e2 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -791,7 +791,7 @@ int  sched_init_domain(struct domain *d, unsigned int 
poolid);
 void sched_destroy_domain(struct domain *d);
 long sched_adjust(struct domain *, struct xen_domctl_scheduler_op *);
 long sched_adjust_global(struct xen_sysctl_scheduler_op *);
-int  sched_id(void);
+int  scheduler_id(void);

 /*
  * sched_get_id_by_name - retrieves a scheduler id given a scheduler name
--
2.34.1