Dario Faggioli
2011-Dec-20 17:47 UTC
sedf: remove useless tracing printk and harmonize comments style.
sched_sedf.c used o have its own mechanism for producing tracing-alike
kind of information (domain block, wakeup, etc.). Nowadays, with an even
not so high number of pCPUs/vCPUs, just trying to enable this makes
the serial console completely unusable, produces tons of very hard to
parse and interpreet logging and can easily livelock Dom0. Moreover,
pretty much the same result this is struggling to get to, is better
achieved by enabling the scheduler-related tracing events, as
it is for the other schedulers (say, credit or credit2).
For all these reasons, this removes that machinery completely. While at
it, check in some cosmetics that harmonize the comments withim themself
and with the rest of the code base.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
diff -r 17d99691e0ec xen/common/sched_sedf.c
--- a/xen/common/sched_sedf.c Tue Dec 20 16:39:56 2011 +0000
+++ b/xen/common/sched_sedf.c Tue Dec 20 17:32:52 2011 +0000
@@ -13,14 +13,6 @@
#include <xen/time.h>
#include <xen/errno.h>
-/*verbosity settings*/
-#define SEDFLEVEL 0
-#define PRINT(_f, _a...) \
- do { \
- if ( (_f) <= SEDFLEVEL ) \
- printk(_a ); \
- } while ( 0 )
-
#define SEDF_CPUONLINE(_pool) \
(((_pool) == NULL) ? &cpupool_free_cpus : (_pool)->cpu_valid)
@@ -66,34 +58,35 @@ struct sedf_vcpu_info {
struct list_head list;
struct list_head extralist[2];
- /*Parameters for EDF*/
- s_time_t period; /*=(relative deadline)*/
- s_time_t slice; /*=worst case execution time*/
+ /* Parameters for EDF */
+ s_time_t period; /* =(relative deadline) */
+ s_time_t slice; /* =worst case execution time */
- /*Advaced Parameters*/
- /*Latency Scaling*/
+ /* Advaced Parameters */
+
+ /* Latency Scaling */
s_time_t period_orig;
s_time_t slice_orig;
s_time_t latency;
- /*status of domain*/
+ /* Status of domain */
int status;
- /*weights for "Scheduling for beginners/ lazy/ etc." ;)*/
+ /* Weights for "Scheduling for beginners/ lazy/ etc." ;) */
short weight;
short extraweight;
- /*Bookkeeping*/
+ /* Bookkeeping */
s_time_t deadl_abs;
s_time_t sched_start_abs;
s_time_t cputime;
- /* times the domain un-/blocked */
+ /* Times the domain un-/blocked */
s_time_t block_abs;
s_time_t unblock_abs;
- /*scores for {util, block penalty}-weighted extratime distribution*/
+ /* Scores for {util, block penalty}-weighted extratime distribution */
int score[2];
s_time_t short_block_lost_tot;
- /*Statistics*/
+ /* Statistics */
s_time_t extra_time_tot;
#ifdef SEDF_STATS
@@ -158,18 +151,16 @@ static inline void extraq_del(struct vcp
{
struct list_head *list = EXTRALIST(d,i);
ASSERT(extraq_on(d,i));
- PRINT(3, "Removing domain %i.%i from L%i extraq\n",
- d->domain->domain_id, d->vcpu_id, i);
list_del(list);
list->next = NULL;
ASSERT(!extraq_on(d, i));
}
-/* adds a domain to the queue of processes which are aware of extra time. List
- is sorted by score, where a lower score means higher priority for an extra
- slice. It also updates the score, by simply subtracting a fixed value from
- each entry, in order to avoid overflow. The algorithm works by simply
- charging each domain that recieved extratime with an inverse of its weight.
+/* Adds a domain to the queue of processes which are aware of extra time. List
+ * is sorted by score, where a lower score means higher priority for an extra
+ * slice. It also updates the score, by simply subtracting a fixed value from
+ * each entry, in order to avoid overflow. The algorithm works by simply
+ * charging each domain that recieved extratime with an inverse of its weight.
*/
static inline void extraq_add_sort_update(struct vcpu *d, int i, int sub)
{
@@ -178,13 +169,7 @@ static inline void extraq_add_sort_updat
ASSERT(!extraq_on(d,i));
- PRINT(3, "Adding domain %i.%i (score= %i, short_pen=
%"PRIi64")"
- " to L%i extraq\n",
- d->domain->domain_id, d->vcpu_id, EDOM_INFO(d)->score[i],
- EDOM_INFO(d)->short_block_lost_tot, i);
-
- /*
- * Iterate through all elements to find our "hole" and on our way
+ /* Iterate through all elements to find our "hole" and on our way
* update all the other scores.
*/
list_for_each ( cur, EXTRAQ(d->processor, i) )
@@ -193,25 +178,18 @@ static inline void extraq_add_sort_updat
curinf->score[i] -= sub;
if ( EDOM_INFO(d)->score[i] < curinf->score[i] )
break;
- PRINT(4,"\tbehind domain %i.%i (score= %i)\n",
- curinf->vcpu->domain->domain_id,
- curinf->vcpu->vcpu_id, curinf->score[i]);
}
- /* cur now contains the element, before which we''ll enqueue. */
- PRINT(3, "\tlist_add to %p\n", cur->prev);
+ /* cur now contains the element, before which we''ll enqueue */
list_add(EXTRALIST(d,i),cur->prev);
- /* Continue updating the extraq. */
+ /* Continue updating the extraq */
if ( (cur != EXTRAQ(d->processor,i)) && sub )
{
for ( cur = cur->next; cur != EXTRAQ(d->processor,i); cur =
cur->next )
{
curinf = list_entry(cur,struct sedf_vcpu_info, extralist[i]);
curinf->score[i] -= sub;
- PRINT(4, "\tupdating domain %i.%i (score= %u)\n",
- curinf->vcpu->domain->domain_id,
- curinf->vcpu->vcpu_id, curinf->score[i]);
}
}
@@ -221,29 +199,14 @@ static inline void extraq_check(struct v
{
if ( extraq_on(d, EXTRA_UTIL_Q) )
{
- PRINT(2,"Dom %i.%i is on L1 extraQ\n",
- d->domain->domain_id, d->vcpu_id);
-
if ( !(EDOM_INFO(d)->status & EXTRA_AWARE) &&
!extra_runs(EDOM_INFO(d)) )
- {
extraq_del(d, EXTRA_UTIL_Q);
- PRINT(2,"Removed dom %i.%i from L1 extraQ\n",
- d->domain->domain_id, d->vcpu_id);
- }
}
else
{
- PRINT(2, "Dom %i.%i is NOT on L1 extraQ\n",
- d->domain->domain_id,
- d->vcpu_id);
-
if ( (EDOM_INFO(d)->status & EXTRA_AWARE) &&
sedf_runnable(d) )
- {
extraq_add_sort_update(d, EXTRA_UTIL_Q, 0);
- PRINT(2,"Added dom %i.%i to L1 extraQ\n",
- d->domain->domain_id, d->vcpu_id);
- }
}
}
@@ -252,7 +215,7 @@ static inline void extraq_check_add_unbl
struct sedf_vcpu_info *inf = EDOM_INFO(d);
if ( inf->status & EXTRA_AWARE )
- /* Put on the weighted extraq without updating any scores. */
+ /* Put on the weighted extraq without updating any scores */
extraq_add_sort_update(d, EXTRA_UTIL_Q, 0);
}
@@ -265,8 +228,6 @@ static inline void __del_from_queue(stru
{
struct list_head *list = LIST(d);
ASSERT(__task_on_queue(d));
- PRINT(3,"Removing domain %i.%i (bop= %"PRIu64") from
runq/waitq\n",
- d->domain->domain_id, d->vcpu_id,
PERIOD_BEGIN(EDOM_INFO(d)));
list_del(list);
list->next = NULL;
ASSERT(!__task_on_queue(d));
@@ -279,13 +240,12 @@ static inline void list_insert_sort(
{
struct list_head *cur;
- /* Iterate through all elements to find our "hole". */
+ /* Iterate through all elements to find our "hole" */
list_for_each( cur, list )
if ( comp(element, cur) < 0 )
break;
- /* cur now contains the element, before which we''ll enqueue. */
- PRINT(3,"\tlist_add to %p\n",cur->prev);
+ /* cur now contains the element, before which we''ll enqueue */
list_add(element, cur->prev);
}
@@ -303,30 +263,26 @@ static int name##_comp(struct list_head*
return 1; \
}
-/* adds a domain to the queue of processes which wait for the beginning of the
- next period; this list is therefore sortet by this time, which is simply
- absol. deadline - period
+/* Adds a domain to the queue of processes which wait for the beginning of the
+ * next period; this list is therefore sortet by this time, which is simply
+ * absol. deadline - period.
*/
DOMAIN_COMPARER(waitq, list, PERIOD_BEGIN(d1), PERIOD_BEGIN(d2));
static inline void __add_to_waitqueue_sort(struct vcpu *v)
{
ASSERT(!__task_on_queue(v));
- PRINT(3,"Adding domain %i.%i (bop= %"PRIu64") to
waitq\n",
- v->domain->domain_id, v->vcpu_id,
PERIOD_BEGIN(EDOM_INFO(v)));
list_insert_sort(WAITQ(v->processor), LIST(v), waitq_comp);
ASSERT(__task_on_queue(v));
}
-/* adds a domain to the queue of processes which have started their current
- period and are runnable (i.e. not blocked, dieing,...). The first element
- on this list is running on the processor, if the list is empty the idle
- task will run. As we are implementing EDF, this list is sorted by deadlines.
+/* Adds a domain to the queue of processes which have started their current
+ * period and are runnable (i.e. not blocked, dieing,...). The first element
+ * on this list is running on the processor, if the list is empty the idle
+ * task will run. As we are implementing EDF, this list is sorted by deadlines.
*/
DOMAIN_COMPARER(runq, list, d1->deadl_abs, d2->deadl_abs);
static inline void __add_to_runqueue_sort(struct vcpu *v)
{
- PRINT(3,"Adding domain %i.%i (deadl= %"PRIu64") to
runq\n",
- v->domain->domain_id, v->vcpu_id,
EDOM_INFO(v)->deadl_abs);
list_insert_sort(RUNQ(v->processor), LIST(v), runq_comp);
}
@@ -445,22 +401,21 @@ static int sedf_pick_cpu(const struct sc
return cpumask_first(&online_affinity);
}
-/*
- * Handles the rescheduling & bookkeeping of domains running in their
+
+/* Handles the rescheduling & bookkeeping of domains running in their
* guaranteed timeslice.
*/
static void desched_edf_dom(s_time_t now, struct vcpu* d)
{
struct sedf_vcpu_info* inf = EDOM_INFO(d);
- /* Current domain is running in real time mode. */
+ /* Current domain is running in real time mode */
ASSERT(__task_on_queue(d));
- /* Update the domain''s cputime. */
+ /* Update the domain''s cputime */
inf->cputime += now - inf->sched_start_abs;
- /*
- * Scheduling decisions which don''t remove the running domain from
the
+ /* Scheduling decisions which don''t remove the running domain from
the
* runq.
*/
if ( (inf->cputime < inf->slice) && sedf_runnable(d) )
@@ -468,8 +423,7 @@ static void desched_edf_dom(s_time_t now
__del_from_queue(d);
- /*
- * Manage bookkeeping (i.e. calculate next deadline, memorise
+ /* Manage bookkeeping (i.e. calculate next deadline, memorise
* overrun-time of slice) of finished domains.
*/
if ( inf->cputime >= inf->slice )
@@ -478,30 +432,30 @@ static void desched_edf_dom(s_time_t now
if ( inf->period < inf->period_orig )
{
- /* This domain runs in latency scaling or burst mode. */
+ /* This domain runs in latency scaling or burst mode */
inf->period *= 2;
inf->slice *= 2;
if ( (inf->period > inf->period_orig) ||
(inf->slice > inf->slice_orig) )
{
- /* Reset slice and period. */
+ /* Reset slice and period */
inf->period = inf->period_orig;
inf->slice = inf->slice_orig;
}
}
- /* Set next deadline. */
+ /* Set next deadline */
inf->deadl_abs += inf->period;
}
- /* Add a runnable domain to the waitqueue. */
+ /* Add a runnable domain to the waitqueue */
if ( sedf_runnable(d) )
{
__add_to_waitqueue_sort(d);
}
else
{
- /* We have a blocked realtime task -> remove it from exqs too. */
+ /* We have a blocked realtime task -> remove it from exqs too */
if ( extraq_on(d, EXTRA_PEN_Q) )
extraq_del(d, EXTRA_PEN_Q);
if ( extraq_on(d, EXTRA_UTIL_Q) )
@@ -521,73 +475,59 @@ static void update_queues(
struct list_head *cur, *tmp;
struct sedf_vcpu_info *curinf;
- PRINT(3,"Updating waitq..\n");
-
- /*
- * Check for the first elements of the waitqueue, whether their
+ /* Check for the first elements of the waitqueue, whether their
* next period has already started.
*/
list_for_each_safe ( cur, tmp, waitq )
{
curinf = list_entry(cur, struct sedf_vcpu_info, list);
- PRINT(4,"\tLooking @ dom %i.%i\n",
- curinf->vcpu->domain->domain_id,
curinf->vcpu->vcpu_id);
if ( PERIOD_BEGIN(curinf) > now )
break;
__del_from_queue(curinf->vcpu);
__add_to_runqueue_sort(curinf->vcpu);
}
- PRINT(3,"Updating runq..\n");
-
- /* Process the runq, find domains that are on the runq that
shouldn''t. */
+ /* Process the runq, find domains that are on the runq that
shouldn''t */
list_for_each_safe ( cur, tmp, runq )
{
curinf = list_entry(cur,struct sedf_vcpu_info,list);
- PRINT(4,"\tLooking @ dom %i.%i\n",
- curinf->vcpu->domain->domain_id,
curinf->vcpu->vcpu_id);
if ( unlikely(curinf->slice == 0) )
{
- /* Ignore domains with empty slice. */
- PRINT(4,"\tUpdating zero-slice domain %i.%i\n",
- curinf->vcpu->domain->domain_id,
- curinf->vcpu->vcpu_id);
+ /* Ignore domains with empty slice */
__del_from_queue(curinf->vcpu);
- /* Move them to their next period. */
+ /* Move them to their next period */
curinf->deadl_abs += curinf->period;
- /* Ensure that the start of the next period is in the future. */
+ /* Ensure that the start of the next period is in the future */
if ( unlikely(PERIOD_BEGIN(curinf) < now) )
curinf->deadl_abs +=
(DIV_UP(now - PERIOD_BEGIN(curinf),
curinf->period)) * curinf->period;
- /* Put them back into the queue. */
+ /* Put them back into the queue */
__add_to_waitqueue_sort(curinf->vcpu);
}
else if ( unlikely((curinf->deadl_abs < now) ||
(curinf->cputime > curinf->slice)) )
{
- /*
- * We missed the deadline or the slice was already finished.
+ /* We missed the deadline or the slice was already finished.
* Might hapen because of dom_adj.
*/
- PRINT(4,"\tDomain %i.%i exceeded it''s deadline/"
- "slice (%"PRIu64" / %"PRIu64") now:
%"PRIu64
- " cputime: %"PRIu64"\n",
- curinf->vcpu->domain->domain_id,
- curinf->vcpu->vcpu_id,
- curinf->deadl_abs, curinf->slice, now,
- curinf->cputime);
+ printk("\tDomain %i.%i exceeded it''s deadline/"
+ "slice (%"PRIu64" / %"PRIu64") now:
%"PRIu64
+ " cputime: %"PRIu64"\n",
+ curinf->vcpu->domain->domain_id,
+ curinf->vcpu->vcpu_id,
+ curinf->deadl_abs, curinf->slice, now,
+ curinf->cputime);
__del_from_queue(curinf->vcpu);
- /* Common case: we miss one period. */
+ /* Common case: we miss one period */
curinf->deadl_abs += curinf->period;
- /*
- * If we are still behind: modulo arithmetic, force deadline
+ /* If we are still behind: modulo arithmetic, force deadline
* to be in future and aligned to period borders.
*/
if ( unlikely(curinf->deadl_abs < now) )
@@ -596,7 +536,7 @@ static void update_queues(
curinf->period) * curinf->period;
ASSERT(curinf->deadl_abs >= now);
- /* Give a fresh slice. */
+ /* Give a fresh slice */
curinf->cputime = 0;
if ( PERIOD_BEGIN(curinf) > now )
__add_to_waitqueue_sort(curinf->vcpu);
@@ -606,17 +546,16 @@ static void update_queues(
else
break;
}
-
- PRINT(3,"done updating the queues\n");
}
/* removes a domain from the head of the according extraQ and
- requeues it at a specified position:
- round-robin extratime: end of extraQ
- weighted ext.: insert in sorted list by score
- if the domain is blocked / has regained its short-block-loss
- time it is not put on any queue */
+ * requeues it at a specified position:
+ * round-robin extratime: end of extraQ
+ * weighted ext.: insert in sorted list by score
+ * if the domain is blocked / has regained its short-block-loss
+ * time it is not put on any queue.
+ */
static void desched_extra_dom(s_time_t now, struct vcpu *d)
{
struct sedf_vcpu_info *inf = EDOM_INFO(d);
@@ -625,29 +564,25 @@ static void desched_extra_dom(s_time_t n
ASSERT(extraq_on(d, i));
- /* Unset all running flags. */
+ /* Unset all running flags */
inf->status &= ~(EXTRA_RUN_PEN | EXTRA_RUN_UTIL);
- /* Fresh slice for the next run. */
+ /* Fresh slice for the next run */
inf->cputime = 0;
- /* Accumulate total extratime. */
+ /* Accumulate total extratime */
inf->extra_time_tot += now - inf->sched_start_abs;
/* Remove extradomain from head of the queue. */
extraq_del(d, i);
- /* Update the score. */
+ /* Update the score */
oldscore = inf->score[i];
if ( i == EXTRA_PEN_Q )
{
- /*domain was running in L0 extraq*/
- /*reduce block lost, probably more sophistication here!*/
+ /* Domain was running in L0 extraq */
+ /* reduce block lost, probably more sophistication here!*/
/*inf->short_block_lost_tot -= EXTRA_QUANTUM;*/
inf->short_block_lost_tot -= now - inf->sched_start_abs;
- PRINT(3,"Domain %i.%i: Short_block_loss:
%"PRIi64"\n",
- inf->vcpu->domain->domain_id, inf->vcpu->vcpu_id,
- inf->short_block_lost_tot);
#if 0
- /*
- * KAF: If we don''t exit short-blocking state at this point
+ /* KAF: If we don''t exit short-blocking state at this point
* domain0 can steal all CPU for up to 10 seconds before
* scheduling settles down (when competing against another
* CPU-bound domain). Doing this seems to make things behave
@@ -656,51 +591,56 @@ static void desched_extra_dom(s_time_t n
if ( inf->short_block_lost_tot <= 0 )
#endif
{
- PRINT(4,"Domain %i.%i compensated short block loss!\n",
- inf->vcpu->domain->domain_id,
inf->vcpu->vcpu_id);
- /*we have (over-)compensated our block penalty*/
+ /* We have (over-)compensated our block penalty */
inf->short_block_lost_tot = 0;
- /*we don''t want a place on the penalty queue anymore!*/
+ /* We don''t want a place on the penalty queue anymore! */
inf->status &= ~EXTRA_WANT_PEN_Q;
goto check_extra_queues;
}
- /*we have to go again for another try in the block-extraq,
- the score is not used incremantally here, as this is
- already done by recalculating the block_lost*/
+ /* We have to go again for another try in the block-extraq,
+ * the score is not used incremantally here, as this is
+ * already done by recalculating the block_lost
+ */
inf->score[EXTRA_PEN_Q] = (inf->period << 10) /
inf->short_block_lost_tot;
oldscore = 0;
}
else
{
- /*domain was running in L1 extraq => score is inverse of
- utilization and is used somewhat incremental!*/
+ /* Domain was running in L1 extraq => score is inverse of
+ * utilization and is used somewhat incremental!
+ */
if ( !inf->extraweight )
- /*NB: use fixed point arithmetic with 10 bits*/
+ {
+ /* NB: use fixed point arithmetic with 10 bits */
inf->score[EXTRA_UTIL_Q] = (inf->period << 10) /
inf->slice;
+ }
else
- /*conversion between realtime utilisation and extrawieght:
- full (ie 100%) utilization is equivalent to 128 extraweight*/
+ {
+ /* Conversion between realtime utilisation and extrawieght:
+ * full (ie 100%) utilization is equivalent to 128 extraweight
+ */
inf->score[EXTRA_UTIL_Q] = (1<<17) / inf->extraweight;
+ }
}
check_extra_queues:
- /* Adding a runnable domain to the right queue and removing blocked ones*/
+ /* Adding a runnable domain to the right queue and removing blocked ones */
if ( sedf_runnable(d) )
{
- /*add according to score: weighted round robin*/
+ /* Add according to score: weighted round robin */
if (((inf->status & EXTRA_AWARE) && (i == EXTRA_UTIL_Q))
||
((inf->status & EXTRA_WANT_PEN_Q) && (i ==
EXTRA_PEN_Q)))
extraq_add_sort_update(d, i, oldscore);
}
else
{
- /*remove this blocked domain from the waitq!*/
+ /* Remove this blocked domain from the waitq! */
__del_from_queue(d);
- /*make sure that we remove a blocked domain from the other
- extraq too*/
+ /* Make sure that we remove a blocked domain from the other
+ * extraq too. */
if ( i == EXTRA_PEN_Q )
{
if ( extraq_on(d, EXTRA_UTIL_Q) )
@@ -732,8 +672,9 @@ static struct task_slice sedf_do_extra_s
if ( !list_empty(extraq[EXTRA_PEN_Q]) )
{
- /*we still have elements on the level 0 extraq
- => let those run first!*/
+ /* We still have elements on the level 0 extraq
+ * => let those run first!
+ */
runinf = list_entry(extraq[EXTRA_PEN_Q]->next,
struct sedf_vcpu_info, extralist[EXTRA_PEN_Q]);
runinf->status |= EXTRA_RUN_PEN;
@@ -747,7 +688,7 @@ static struct task_slice sedf_do_extra_s
{
if ( !list_empty(extraq[EXTRA_UTIL_Q]) )
{
- /*use elements from the normal extraqueue*/
+ /* Use elements from the normal extraqueue */
runinf = list_entry(extraq[EXTRA_UTIL_Q]->next,
struct sedf_vcpu_info,
extralist[EXTRA_UTIL_Q]);
@@ -773,10 +714,11 @@ static struct task_slice sedf_do_extra_s
/* Main scheduling function
- Reasons for calling this function are:
- -timeslice for the current period used up
- -domain on waitqueue has started it''s period
- -and various others ;) in general: determine which domain to run next*/
+ * Reasons for calling this function are:
+ * -timeslice for the current period used up
+ * -domain on waitqueue has started it''s period
+ * -and various others ;) in general: determine which domain to run next
+ */
static struct task_slice sedf_do_schedule(
const struct scheduler *ops, s_time_t now, bool_t tasklet_work_scheduled)
{
@@ -789,13 +731,14 @@ static struct task_slice sedf_do_schedul
struct sedf_vcpu_info *runinf, *waitinf;
struct task_slice ret;
- /*idle tasks don''t need any of the following stuf*/
+ /* Idle tasks don''t need any of the following stuf */
if ( is_idle_vcpu(current) )
goto check_waitq;
- /* create local state of the status of the domain, in order to avoid
- inconsistent state during scheduling decisions, because data for
- vcpu_runnable is not protected by the scheduling lock!*/
+ /* Create local state of the status of the domain, in order to avoid
+ * inconsistent state during scheduling decisions, because data for
+ * vcpu_runnable is not protected by the scheduling lock!
+ */
if ( !vcpu_runnable(current) )
inf->status |= SEDF_ASLEEP;
@@ -804,7 +747,7 @@ static struct task_slice sedf_do_schedul
if ( unlikely(extra_runs(inf)) )
{
- /*special treatment of domains running in extra time*/
+ /* Special treatment of domains running in extra time */
desched_extra_dom(now, current);
}
else
@@ -814,10 +757,11 @@ static struct task_slice sedf_do_schedul
check_waitq:
update_queues(now, runq, waitq);
- /*now simply pick the first domain from the runqueue, which has the
- earliest deadline, because the list is sorted*/
-
- /* Tasklet work (which runs in idle VCPU context) overrides all else. */
+ /* Now simply pick the first domain from the runqueue, which has the
+ * earliest deadline, because the list is sorted
+ *
+ * Tasklet work (which runs in idle VCPU context) overrides all else.
+ */
if ( tasklet_work_scheduled ||
(list_empty(runq) && list_empty(waitq)) ||
unlikely(!cpumask_test_cpu(cpu, SEDF_CPUONLINE(per_cpu(cpupool,
cpu)))) )
@@ -833,9 +777,10 @@ static struct task_slice sedf_do_schedul
{
waitinf = list_entry(waitq->next,
struct sedf_vcpu_info,list);
- /*rerun scheduler, when scheduled domain reaches it''s
- end of slice or the first domain from the waitqueue
- gets ready*/
+ /* Rerun scheduler, when scheduled domain reaches it''s
+ * end of slice or the first domain from the waitqueue
+ * gets ready.
+ */
ret.time = MIN(now + runinf->slice - runinf->cputime,
PERIOD_BEGIN(waitinf)) - now;
}
@@ -847,14 +792,15 @@ static struct task_slice sedf_do_schedul
else
{
waitinf = list_entry(waitq->next,struct sedf_vcpu_info, list);
- /*we could not find any suitable domain
- => look for domains that are aware of extratime*/
+ /* We could not find any suitable domain
+ * => look for domains that are aware of extratime*/
ret = sedf_do_extra_schedule(now, PERIOD_BEGIN(waitinf),
extraq, cpu);
}
- /*TODO: Do something USEFUL when this happens and find out, why it
- still can happen!!!*/
+ /* TODO: Do something USEFUL when this happens and find out, why it
+ * still can happen!!!
+ */
if ( ret.time < 0)
{
printk("Ouch! We are seriously BEHIND schedule!
%"PRIi64"\n",
@@ -874,9 +820,6 @@ static struct task_slice sedf_do_schedul
static void sedf_sleep(const struct scheduler *ops, struct vcpu *d)
{
- PRINT(2,"sedf_sleep was called, domain-id %i.%i\n",
- d->domain->domain_id, d->vcpu_id);
-
if ( is_idle_vcpu(d) )
return;
@@ -972,27 +915,29 @@ static void sedf_sleep(const struct sche
static void unblock_short_extra_support(
struct sedf_vcpu_info* inf, s_time_t now)
{
- /*this unblocking scheme tries to support the domain, by assigning it
- a priority in extratime distribution according to the loss of time
- in this slice due to blocking*/
+ /* This unblocking scheme tries to support the domain, by assigning it
+ * a priority in extratime distribution according to the loss of time
+ * in this slice due to blocking
+ */
s_time_t pen;
- /*no more realtime execution in this period!*/
+ /* No more realtime execution in this period! */
inf->deadl_abs += inf->period;
if ( likely(inf->block_abs) )
{
- //treat blocked time as consumed by the domain*/
+ /* Treat blocked time as consumed by the domain */
/*inf->cputime += now - inf->block_abs;*/
- /*penalty is time the domain would have
- had if it continued to run */
+ /* Penalty is time the domain would have
+ * had if it continued to run.
+ */
pen = (inf->slice - inf->cputime);
if ( pen < 0 )
pen = 0;
- /*accumulate all penalties over the periods*/
+ /* Accumulate all penalties over the periods */
/*inf->short_block_lost_tot += pen;*/
- /*set penalty to the current value*/
+ /* Set penalty to the current value */
inf->short_block_lost_tot = pen;
- /*not sure which one is better.. but seems to work well...*/
+ /* Not sure which one is better.. but seems to work well... */
if ( inf->short_block_lost_tot )
{
@@ -1002,28 +947,30 @@ static void unblock_short_extra_support(
inf->pen_extra_blocks++;
#endif
if ( extraq_on(inf->vcpu, EXTRA_PEN_Q) )
- /*remove domain for possible resorting!*/
+ /* Remove domain for possible resorting! */
extraq_del(inf->vcpu, EXTRA_PEN_Q);
else
- /*remember that we want to be on the penalty q
- so that we can continue when we (un-)block
- in penalty-extratime*/
+ /* Remember that we want to be on the penalty q
+ * so that we can continue when we (un-)block
+ * in penalty-extratime
+ */
inf->status |= EXTRA_WANT_PEN_Q;
- /*(re-)add domain to the penalty extraq*/
+ /* (re-)add domain to the penalty extraq */
extraq_add_sort_update(inf->vcpu, EXTRA_PEN_Q, 0);
}
}
- /*give it a fresh slice in the next period!*/
+ /* Give it a fresh slice in the next period! */
inf->cputime = 0;
}
static void unblock_long_cons_b(struct sedf_vcpu_info* inf,s_time_t now)
{
- /*Conservative 2b*/
- /*Treat the unblocking time as a start of a new period */
+ /* Conservative 2b */
+
+ /* Treat the unblocking time as a start of a new period */
inf->deadl_abs = now + inf->period;
inf->cputime = 0;
}
@@ -1046,15 +993,16 @@ static inline int get_run_type(struct vc
}
-/*Compares two domains in the relation of whether the one is allowed to
- interrupt the others execution.
- It returns true (!=0) if a switch to the other domain is good.
- Current Priority scheme is as follows:
- EDF > L0 (penalty based) extra-time >
- L1 (utilization) extra-time > idle-domain
- In the same class priorities are assigned as following:
- EDF: early deadline > late deadline
- L0 extra-time: lower score > higher score*/
+/* Compares two domains in the relation of whether the one is allowed to
+ * interrupt the others execution.
+ * It returns true (!=0) if a switch to the other domain is good.
+ * Current Priority scheme is as follows:
+ * EDF > L0 (penalty based) extra-time >
+ * L1 (utilization) extra-time > idle-domain
+ * In the same class priorities are assigned as following:
+ * EDF: early deadline > late deadline
+ * L0 extra-time: lower score > higher score
+ */
static inline int should_switch(struct vcpu *cur,
struct vcpu *other,
s_time_t now)
@@ -1063,19 +1011,19 @@ static inline int should_switch(struct v
cur_inf = EDOM_INFO(cur);
other_inf = EDOM_INFO(other);
- /* Check whether we need to make an earlier scheduling decision. */
+ /* Check whether we need to make an earlier scheduling decision */
if ( PERIOD_BEGIN(other_inf) <
CPU_INFO(other->processor)->current_slice_expires )
return 1;
- /* No timing-based switches need to be taken into account here. */
+ /* No timing-based switches need to be taken into account here */
switch ( get_run_type(cur) )
{
case DOMAIN_EDF:
- /* Do not interrupt a running EDF domain. */
+ /* Do not interrupt a running EDF domain */
return 0;
case DOMAIN_EXTRA_PEN:
- /* Check whether we also want the L0 ex-q with lower score. */
+ /* Check whether we also want the L0 ex-q with lower score */
return ((other_inf->status & EXTRA_WANT_PEN_Q) &&
(other_inf->score[EXTRA_PEN_Q] <
cur_inf->score[EXTRA_PEN_Q]));
@@ -1096,18 +1044,11 @@ static void sedf_wake(const struct sched
s_time_t now = NOW();
struct sedf_vcpu_info* inf = EDOM_INFO(d);
- PRINT(3, "sedf_wake was called, domain-id
%i.%i\n",d->domain->domain_id,
- d->vcpu_id);
-
if ( unlikely(is_idle_vcpu(d)) )
return;
if ( unlikely(__task_on_queue(d)) )
- {
- PRINT(3,"\tdomain %i.%i is already in some queue\n",
- d->domain->domain_id, d->vcpu_id);
return;
- }
ASSERT(!sedf_runnable(d));
inf->status &= ~SEDF_ASLEEP;
@@ -1116,28 +1057,24 @@ static void sedf_wake(const struct sched
if ( unlikely(inf->deadl_abs == 0) )
{
- /*initial setup of the deadline*/
+ /* Initial setup of the deadline */
inf->deadl_abs = now + inf->slice;
}
- PRINT(3, "waking up domain %i.%i (deadl= %"PRIu64" period=
%"PRIu64
- "now= %"PRIu64")\n",
- d->domain->domain_id, d->vcpu_id, inf->deadl_abs,
inf->period, now);
-
#ifdef SEDF_STATS
inf->block_tot++;
#endif
if ( unlikely(now < PERIOD_BEGIN(inf)) )
{
- PRINT(4,"extratime unblock\n");
- /* unblocking in extra-time! */
+ /* Unblocking in extra-time! */
if ( inf->status & EXTRA_WANT_PEN_Q )
{
- /*we have a domain that wants compensation
- for block penalty and did just block in
- its compensation time. Give it another
- chance!*/
+ /* We have a domain that wants compensation
+ * for block penalty and did just block in
+ * its compensation time. Give it another
+ * chance!
+ */
extraq_add_sort_update(d, EXTRA_PEN_Q, 0);
}
extraq_check_add_unblocked(d, 0);
@@ -1146,8 +1083,7 @@ static void sedf_wake(const struct sched
{
if ( now < inf->deadl_abs )
{
- PRINT(4,"short unblocking\n");
- /*short blocking*/
+ /* Short blocking */
#ifdef SEDF_STATS
inf->short_block_tot++;
#endif
@@ -1157,8 +1093,7 @@ static void sedf_wake(const struct sched
}
else
{
- PRINT(4,"long unblocking\n");
- /*long unblocking*/
+ /* Long unblocking */
#ifdef SEDF_STATS
inf->long_block_tot++;
#endif
@@ -1168,24 +1103,13 @@ static void sedf_wake(const struct sched
}
}
- PRINT(3, "woke up domain %i.%i (deadl= %"PRIu64" period=
%"PRIu64
- "now= %"PRIu64")\n",
- d->domain->domain_id, d->vcpu_id, inf->deadl_abs,
- inf->period, now);
-
if ( PERIOD_BEGIN(inf) > now )
- {
__add_to_waitqueue_sort(d);
- PRINT(3,"added to waitq\n");
- }
else
- {
__add_to_runqueue_sort(d);
- PRINT(3,"added to runq\n");
- }
#ifdef SEDF_STATS
- /*do some statistics here...*/
+ /* Do some statistics here... */
if ( inf->block_abs != 0 )
{
inf->block_time_tot += now - inf->block_abs;
@@ -1194,12 +1118,13 @@ static void sedf_wake(const struct sched
}
#endif
- /*sanity check: make sure each extra-aware domain IS on the util-q!*/
+ /* Sanity check: make sure each extra-aware domain IS on the util-q! */
ASSERT(IMPLY(inf->status & EXTRA_AWARE, extraq_on(d,
EXTRA_UTIL_Q)));
ASSERT(__task_on_queue(d));
- /*check whether the awakened task needs to invoke the do_schedule
- routine. Try to avoid unnecessary runs but:
- Save approximation: Always switch to scheduler!*/
+ /* Check whether the awakened task needs to invoke the do_schedule
+ * routine. Try to avoid unnecessary runs but:
+ * Save approximation: Always switch to scheduler!
+ */
ASSERT(d->processor >= 0);
ASSERT(d->processor < nr_cpu_ids);
ASSERT(per_cpu(schedule_data, d->processor).curr);
@@ -1244,7 +1169,7 @@ static void sedf_dump_domain(struct vcpu
}
-/* dumps all domains on the specified cpu */
+/* Dumps all domains on the specified cpu */
static void sedf_dump_cpu_state(const struct scheduler *ops, int i)
{
struct list_head *list, *queue, *tmp;
@@ -1319,7 +1244,7 @@ static void sedf_dump_cpu_state(const st
}
-/* Adjusts periods and slices of the domains accordingly to their weights. */
+/* Adjusts periods and slices of the domains accordingly to their weights */
static int sedf_adjust_weights(struct cpupool *c, struct
xen_domctl_scheduler_op *cmd)
{
struct vcpu *p;
@@ -1335,7 +1260,7 @@ static int sedf_adjust_weights(struct cp
return -ENOMEM;
}
- /* Sum across all weights. */
+ /* Sum across all weights */
rcu_read_lock(&domlist_read_lock);
for_each_domain_in_cpupool( d, c )
{
@@ -1350,11 +1275,13 @@ static int sedf_adjust_weights(struct cp
}
else
{
- /*don''t modify domains who don''t have a
weight, but sum
- up the time they need, projected to a WEIGHT_PERIOD,
- so that this time is not given to the weight-driven
- domains*/
- /*check for overflows*/
+ /* Don''t modify domains who don''t have a
weight, but sum
+ * up the time they need, projected to a WEIGHT_PERIOD,
+ * so that this time is not given to the weight-driven
+ * domains
+ */
+
+ /* Check for overflows */
ASSERT((WEIGHT_PERIOD < ULONG_MAX)
&& (EDOM_INFO(p)->slice_orig <
ULONG_MAX));
sumt[cpu] +=
@@ -1365,7 +1292,7 @@ static int sedf_adjust_weights(struct cp
}
rcu_read_unlock(&domlist_read_lock);
- /* Adjust all slices (and periods) to the new weight. */
+ /* Adjust all slices (and periods) to the new weight */
rcu_read_lock(&domlist_read_lock);
for_each_domain_in_cpupool( d, c )
{
@@ -1393,20 +1320,15 @@ static int sedf_adjust_weights(struct cp
}
-/* set or fetch domain scheduling parameters */
+/* Set or fetch domain scheduling parameters */
static int sedf_adjust(const struct scheduler *ops, struct domain *p, struct
xen_domctl_scheduler_op *op)
{
struct vcpu *v;
int rc;
- PRINT(2,"sedf_adjust was called, domain-id %i new period
%"PRIu64" "
- "new slice %"PRIu64"\nlatency %"PRIu64"
extra:%s\n",
- p->domain_id, op->u.sedf.period, op->u.sedf.slice,
- op->u.sedf.latency,
(op->u.sedf.extratime)?"yes":"no");
-
if ( op->cmd == XEN_DOMCTL_SCHEDOP_putinfo )
{
- /* Check for sane parameters. */
+ /* Check for sane parameters */
if ( !op->u.sedf.period && !op->u.sedf.weight )
return -EINVAL;
if ( op->u.sedf.weight )
@@ -1414,7 +1336,7 @@ static int sedf_adjust(const struct sche
if ( (op->u.sedf.extratime & EXTRA_AWARE) &&
(!op->u.sedf.period) )
{
- /* Weight-driven domains with extratime only. */
+ /* Weight-driven domains with extratime only */
for_each_vcpu ( p, v )
{
EDOM_INFO(v)->extraweight = op->u.sedf.weight;
@@ -1425,7 +1347,7 @@ static int sedf_adjust(const struct sche
}
else
{
- /* Weight-driven domains with real-time execution. */
+ /* Weight-driven domains with real-time execution */
for_each_vcpu ( p, v )
EDOM_INFO(v)->weight = op->u.sedf.weight;
}
@@ -1435,8 +1357,7 @@ static int sedf_adjust(const struct sche
/* Time-driven domains. */
for_each_vcpu ( p, v )
{
- /*
- * Sanity checking: note that disabling extra weight requires
+ /* Sanity checking: note that disabling extra weight requires
* that we set a non-zero slice.
*/
if ( (op->u.sedf.period > PERIOD_MAX) ||
@@ -1477,7 +1398,6 @@ static int sedf_adjust(const struct sche
op->u.sedf.weight = EDOM_INFO(p->vcpu[0])->weight;
}
- PRINT(2,"sedf_adjust_finished\n");
return 0;
}
--
<<This happens because I choose it to happen!>> (Raistlin Majere)
-------------------------------------------------------------------
Dario Faggioli, http://retis.sssup.it/people/faggioli
Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK)
PhD Candidate, ReTiS Lab, Scuola Superiore Sant''Anna, Pisa (Italy)
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