kernel26-magellan/patches-2.6.16-r3/0010-2.6.16-sched-iso-4.1.patch

 include/linux/sched.h  |    9 ++++--
 include/linux/sysctl.h |    1 
 kernel/sched.c         |   72 ++++++++++++++++++++++++++++++++++++++++++++++---
 kernel/sysctl.c        |   22 ++++++++++----
 4 files changed, 91 insertions(+), 13 deletions(-)

Index: linux-2.6.16-ck1/include/linux/sched.h
===================================================================
--- linux-2.6.16-ck1.orig/include/linux/sched.h	2006-03-20 20:46:49.000000000 +1100
+++ linux-2.6.16-ck1/include/linux/sched.h	2006-03-20 20:46:50.000000000 +1100
@@ -162,9 +162,10 @@ extern unsigned long weighted_cpuload(co
 #define SCHED_FIFO		1
 #define SCHED_RR		2
 #define SCHED_BATCH		3
+#define SCHED_ISO		4
 
 #define SCHED_MIN		0
-#define SCHED_MAX		3
+#define SCHED_MAX		4
 
 #define SCHED_RANGE(policy)	((policy) >= SCHED_MIN && \
 					(policy) <= SCHED_MAX)
@@ -208,7 +209,7 @@ extern void show_stack(struct task_struc
 
 void io_schedule(void);
 long io_schedule_timeout(long timeout);
-extern int sched_interactive, sched_compute;
+extern int sched_interactive, sched_compute, sched_iso_cpu;
 
 extern void cpu_init (void);
 extern void trap_init(void);
@@ -498,7 +499,8 @@ struct signal_struct {
 
 #define MAX_PRIO		(MAX_RT_PRIO + 40)
 
-#define rt_task(p)		(unlikely((p)->prio < MAX_RT_PRIO))
+#define rt_task(p)		(unlikely(SCHED_RT((p)->policy)))
+#define iso_task(p)		((p)->policy == SCHED_ISO)
 
 /*
  * Some day this will be a full-fledged user tracking system..
@@ -956,6 +958,7 @@ static inline void put_task_struct(struc
 #define PF_RANDOMIZE	0x00800000	/* randomize virtual address space */
 #define PF_SWAPWRITE	0x01000000	/* Allowed to write to swap */
 #define PF_NONSLEEP	0x02000000	/* Waiting on in kernel activity */
+#define PF_ISOREF	0x04000000	/* SCHED_ISO task has used up quota */
 
 /*
  * Only the _current_ task can read/write to tsk->flags, but other
Index: linux-2.6.16-ck1/include/linux/sysctl.h
===================================================================
--- linux-2.6.16-ck1.orig/include/linux/sysctl.h	2006-03-20 20:46:48.000000000 +1100
+++ linux-2.6.16-ck1/include/linux/sysctl.h	2006-03-20 20:46:50.000000000 +1100
@@ -150,6 +150,7 @@ enum
 	KERN_IA64_UNALIGNED=72, /* int: ia64 unaligned userland trap enable */
 	KERN_INTERACTIVE=73,	/* interactive tasks can have cpu bursts */
 	KERN_COMPUTE=74,	/* adjust timeslices for a compute server */
+	KERN_ISO_CPU=75,	/* percent cpu SCHED_ISO tasks run SCHED_RR */
 };
 
 
Index: linux-2.6.16-ck1/kernel/sched.c
===================================================================
--- linux-2.6.16-ck1.orig/kernel/sched.c	2006-03-20 20:46:49.000000000 +1100
+++ linux-2.6.16-ck1/kernel/sched.c	2006-03-20 20:46:50.000000000 +1100
@@ -92,6 +92,9 @@ int sched_compute __read_mostly = 0;
 #define RR_INTERVAL()		(_RR_INTERVAL * (1 + 16 * sched_compute))
 #define DEF_TIMESLICE		(RR_INTERVAL() * 19)
 
+int sched_iso_cpu __read_mostly = 80;
+#define ISO_PERIOD		(5 * HZ)
+
 #define task_hot(p, now, sd) ((long long) ((now) - (p)->timestamp)	\
 				< (long long) (sd)->cache_hot_time)
 
@@ -129,6 +132,9 @@ struct runqueue {
 	 */
 	unsigned long nr_uninterruptible;
 
+	unsigned long iso_ticks;
+	unsigned int iso_refractory;
+
 	unsigned long long timestamp_last_tick;
 	unsigned int cache_ticks, preempted;
 	task_t *curr, *idle;
@@ -713,6 +719,17 @@ static int effective_prio(const task_t *
 	if (rt_task(p))
 		return p->prio;
 
+	if (iso_task(p)) {
+		if (likely(!(p->flags & PF_ISOREF)))
+			/*
+			 * If SCHED_ISO tasks have not used up their real time
+			 * quota they have run just better than highest
+			 * SCHED_NORMAL priority. Otherwise they run as
+			 * SCHED_NORMAL.
+			 */
+			return MAX_RT_PRIO - 1;
+	}
+
 	full_slice = slice(p);
 	if (full_slice > p->slice)
 		used_slice = full_slice - p->slice;
@@ -2522,6 +2539,22 @@ static void time_slice_expired(task_t *p
 }
 
 /*
+ * Test if SCHED_ISO tasks have run longer than their alloted period as RT
+ * tasks and set the refractory flag if necessary. There is 10% hysteresis
+ * for unsetting the flag.
+ */
+static inline unsigned int test_ret_isorefractory(runqueue_t *rq)
+{
+	if (likely(!rq->iso_refractory)) {
+		if (rq->iso_ticks / ISO_PERIOD > sched_iso_cpu)
+			rq->iso_refractory = 1;
+	} else
+		if (rq->iso_ticks / ISO_PERIOD < (sched_iso_cpu * 90 / 100))
+			rq->iso_refractory = 0;
+	return rq->iso_refractory;
+}
+
+/*
  * This function gets called by the timer code, with HZ frequency.
  * We call it with interrupts disabled.
  */
@@ -2549,15 +2582,33 @@ void scheduler_tick(void)
 		set_tsk_need_resched(p);
 		goto out;
 	}
+
+	spin_lock(&rq->lock);
+	if (unlikely((rt_task(p) || (iso_task(p) && !rq->iso_refractory)) &&
+		p->mm)) {
+			if (rq->iso_ticks <= (ISO_PERIOD * 100) - 100)
+			rq->iso_ticks += 100;
+	} else
+		rq->iso_ticks = rq->iso_ticks * (ISO_PERIOD - 1) / ISO_PERIOD;
+
+	if (iso_task(p)) {
+		if (unlikely(test_ret_isorefractory(rq))) {
+			if (!(p->flags & PF_ISOREF)) {
+				set_tsk_need_resched(p);
+				p->flags |= PF_ISOREF;
+			}
+		} else
+			p->flags &= ~PF_ISOREF;
+	}
+
 	/*
 	 * SCHED_FIFO tasks never run out of timeslice.
 	 */
 	if (unlikely(p->policy == SCHED_FIFO)) {
 		expired_balance = 0;
-		goto out;
+		goto out_unlock;
 	}
 
-	spin_lock(&rq->lock);
 	debit = ns_diff(rq->timestamp_last_tick, p->timestamp);
 	p->ns_debit += debit;
 	if (p->ns_debit < NSJIFFY)
@@ -2696,7 +2747,7 @@ static int dependent_sleeper(const int t
 		task_t *smt_curr = smt_rq->curr;
 
 		/* Kernel threads do not participate in dependent sleeping */
-		if (!p->mm || !smt_curr->mm || rt_task(p))
+		if (!p->mm || !smt_curr->mm || rt_task(p) || iso_task(p))
 			goto check_smt_task;
 
 		/*
@@ -2723,7 +2774,7 @@ static int dependent_sleeper(const int t
 
 check_smt_task:
 		if ((!smt_curr->mm && smt_curr != smt_rq->idle) ||
-			rt_task(smt_curr))
+			rt_task(smt_curr) || iso_task(smt_curr))
 				continue;
 		if (!p->mm) {
 			wakeup_busy_runqueue(smt_rq);
@@ -3525,9 +3576,19 @@ int sched_setscheduler(struct task_struc
 {
 	int retval;
 	int queued, oldprio, oldpolicy = -1;
+	struct sched_param zero_param = { .sched_priority = 0 };
 	unsigned long flags;
 	runqueue_t *rq;
 
+	if (SCHED_RT(policy) && !capable(CAP_SYS_NICE)) {
+		/*
+		 * If the caller requested an RT policy without having the
+		 * necessary rights, we downgrade the policy to SCHED_ISO.
+		 * We also set the parameter to zero to pass the checks.
+		 */
+		policy = SCHED_ISO;
+		param = &zero_param;
+	}
 recheck:
 	/* double check policy once rq lock held */
 	if (policy < 0)
@@ -4029,6 +4090,7 @@ asmlinkage long sys_sched_get_priority_m
 		break;
 	case SCHED_NORMAL:
 	case SCHED_BATCH:
+	case SCHED_ISO:
 		ret = 0;
 		break;
 	}
@@ -4053,6 +4115,7 @@ asmlinkage long sys_sched_get_priority_m
 		break;
 	case SCHED_NORMAL:
 	case SCHED_BATCH:
+	case SCHED_ISO:
 		ret = 0;
 	}
 	return ret;
@@ -5903,6 +5966,7 @@ void __init sched_init(void)
 		rq->nr_running = 0;
 		rq->cache_ticks = 0;
 		rq->preempted = 0;
+		rq->iso_ticks = 0;
 
 #ifdef CONFIG_SMP
 		rq->sd = NULL;
Index: linux-2.6.16-ck1/kernel/sysctl.c
===================================================================
--- linux-2.6.16-ck1.orig/kernel/sysctl.c	2006-03-20 20:46:48.000000000 +1100
+++ linux-2.6.16-ck1/kernel/sysctl.c	2006-03-20 20:46:50.000000000 +1100
@@ -229,6 +229,11 @@ static ctl_table root_table[] = {
 	{ .ctl_name = 0 }
 };
 
+/* Constants for minimum and maximum testing.
+   We use these as one-element integer vectors. */
+static int zero;
+static int one_hundred = 100;
+
 static ctl_table kern_table[] = {
 	{
 		.ctl_name	= KERN_OSTYPE,
@@ -639,6 +644,17 @@ static ctl_table kern_table[] = {
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec,
 	},
+	{
+		.ctl_name	= KERN_ISO_CPU,
+		.procname	= "iso_cpu",
+		.data		= &sched_iso_cpu,
+		.maxlen		= sizeof (int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec_minmax,
+		.strategy	= &sysctl_intvec,
+		.extra1		= &zero,
+		.extra2		= &one_hundred,
+	},
 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 	{
 		.ctl_name       = KERN_UNKNOWN_NMI_PANIC,
@@ -702,12 +718,6 @@ static ctl_table kern_table[] = {
 	{ .ctl_name = 0 }
 };
 
-/* Constants for minimum and maximum testing in vm_table.
-   We use these as one-element integer vectors. */
-static int zero;
-static int one_hundred = 100;
-
-
 static ctl_table vm_table[] = {
 	{
 		.ctl_name	= VM_OVERCOMMIT_MEMORY,
1	include/linux/sched.h \| 9 ++++--
2	include/linux/sysctl.h \| 1
3	kernel/sched.c \| 72 ++++++++++++++++++++++++++++++++++++++++++++++---
4	kernel/sysctl.c \| 22 ++++++++++----
5	4 files changed, 91 insertions(+), 13 deletions(-)
6
7	Index: linux-2.6.16-ck1/include/linux/sched.h
8	===================================================================
9	--- linux-2.6.16-ck1.orig/include/linux/sched.h 2006-03-20 20:46:49.000000000 +1100
10	+++ linux-2.6.16-ck1/include/linux/sched.h 2006-03-20 20:46:50.000000000 +1100
11	@@ -162,9 +162,10 @@ extern unsigned long weighted_cpuload(co
12	#define SCHED_FIFO 1
13	#define SCHED_RR 2
14	#define SCHED_BATCH 3
15	+#define SCHED_ISO 4
16
17	#define SCHED_MIN 0
18	-#define SCHED_MAX 3
19	+#define SCHED_MAX 4
20
21	#define SCHED_RANGE(policy) ((policy) >= SCHED_MIN && \
22	(policy) <= SCHED_MAX)
23	@@ -208,7 +209,7 @@ extern void show_stack(struct task_struc
24
25	void io_schedule(void);
26	long io_schedule_timeout(long timeout);
27	-extern int sched_interactive, sched_compute;
28	+extern int sched_interactive, sched_compute, sched_iso_cpu;
29
30	extern void cpu_init (void);
31	extern void trap_init(void);
32	@@ -498,7 +499,8 @@ struct signal_struct {
33
34	#define MAX_PRIO (MAX_RT_PRIO + 40)
35
36	-#define rt_task(p) (unlikely((p)->prio < MAX_RT_PRIO))
37	+#define rt_task(p) (unlikely(SCHED_RT((p)->policy)))
38	+#define iso_task(p) ((p)->policy == SCHED_ISO)
39
40	/*
41	* Some day this will be a full-fledged user tracking system..
42	@@ -956,6 +958,7 @@ static inline void put_task_struct(struc
43	#define PF_RANDOMIZE 0x00800000 /* randomize virtual address space */
44	#define PF_SWAPWRITE 0x01000000 /* Allowed to write to swap */
45	#define PF_NONSLEEP 0x02000000 /* Waiting on in kernel activity */
46	+#define PF_ISOREF 0x04000000 /* SCHED_ISO task has used up quota */
47
48	/*
49	* Only the _current_ task can read/write to tsk->flags, but other
50	Index: linux-2.6.16-ck1/include/linux/sysctl.h
51	===================================================================
52	--- linux-2.6.16-ck1.orig/include/linux/sysctl.h 2006-03-20 20:46:48.000000000 +1100
53	+++ linux-2.6.16-ck1/include/linux/sysctl.h 2006-03-20 20:46:50.000000000 +1100
54	@@ -150,6 +150,7 @@ enum
55	KERN_IA64_UNALIGNED=72, /* int: ia64 unaligned userland trap enable */
56	KERN_INTERACTIVE=73, /* interactive tasks can have cpu bursts */
57	KERN_COMPUTE=74, /* adjust timeslices for a compute server */
58	+ KERN_ISO_CPU=75, /* percent cpu SCHED_ISO tasks run SCHED_RR */
59	};
60
61
62	Index: linux-2.6.16-ck1/kernel/sched.c
63	===================================================================
64	--- linux-2.6.16-ck1.orig/kernel/sched.c 2006-03-20 20:46:49.000000000 +1100
65	+++ linux-2.6.16-ck1/kernel/sched.c 2006-03-20 20:46:50.000000000 +1100
66	@@ -92,6 +92,9 @@ int sched_compute __read_mostly = 0;
67	#define RR_INTERVAL() (_RR_INTERVAL * (1 + 16 * sched_compute))
68	#define DEF_TIMESLICE (RR_INTERVAL() * 19)
69
70	+int sched_iso_cpu __read_mostly = 80;
71	+#define ISO_PERIOD (5 * HZ)
72	+
73	#define task_hot(p, now, sd) ((long long) ((now) - (p)->timestamp) \
74	< (long long) (sd)->cache_hot_time)
75
76	@@ -129,6 +132,9 @@ struct runqueue {
77	*/
78	unsigned long nr_uninterruptible;
79
80	+ unsigned long iso_ticks;
81	+ unsigned int iso_refractory;
82	+
83	unsigned long long timestamp_last_tick;
84	unsigned int cache_ticks, preempted;
85	task_t curr, idle;
86	@@ -713,6 +719,17 @@ static int effective_prio(const task_t *
87	if (rt_task(p))
88	return p->prio;
89
90	+ if (iso_task(p)) {
91	+ if (likely(!(p->flags & PF_ISOREF)))
92	+ /*
93	+ * If SCHED_ISO tasks have not used up their real time
94	+ * quota they have run just better than highest
95	+ * SCHED_NORMAL priority. Otherwise they run as
96	+ * SCHED_NORMAL.
97	+ */
98	+ return MAX_RT_PRIO - 1;
99	+ }
100	+
101	full_slice = slice(p);
102	if (full_slice > p->slice)
103	used_slice = full_slice - p->slice;
104	@@ -2522,6 +2539,22 @@ static void time_slice_expired(task_t *p
105	}
106
107	/*
108	+ * Test if SCHED_ISO tasks have run longer than their alloted period as RT
109	+ * tasks and set the refractory flag if necessary. There is 10% hysteresis
110	+ * for unsetting the flag.
111	+ */
112	+static inline unsigned int test_ret_isorefractory(runqueue_t *rq)
113	+{
114	+ if (likely(!rq->iso_refractory)) {
115	+ if (rq->iso_ticks / ISO_PERIOD > sched_iso_cpu)
116	+ rq->iso_refractory = 1;
117	+ } else
118	+ if (rq->iso_ticks / ISO_PERIOD < (sched_iso_cpu * 90 / 100))
119	+ rq->iso_refractory = 0;
120	+ return rq->iso_refractory;
121	+}
122	+
123	+/*
124	* This function gets called by the timer code, with HZ frequency.
125	* We call it with interrupts disabled.
126	*/
127	@@ -2549,15 +2582,33 @@ void scheduler_tick(void)
128	set_tsk_need_resched(p);
129	goto out;
130	}
131	+
132	+ spin_lock(&rq->lock);
133	+ if (unlikely((rt_task(p) \|\| (iso_task(p) && !rq->iso_refractory)) &&
134	+ p->mm)) {
135	+ if (rq->iso_ticks <= (ISO_PERIOD * 100) - 100)
136	+ rq->iso_ticks += 100;
137	+ } else
138	+ rq->iso_ticks = rq->iso_ticks * (ISO_PERIOD - 1) / ISO_PERIOD;
139	+
140	+ if (iso_task(p)) {
141	+ if (unlikely(test_ret_isorefractory(rq))) {
142	+ if (!(p->flags & PF_ISOREF)) {
143	+ set_tsk_need_resched(p);
144	+ p->flags \|= PF_ISOREF;
145	+ }
146	+ } else
147	+ p->flags &= ~PF_ISOREF;
148	+ }
149	+
150	/*
151	* SCHED_FIFO tasks never run out of timeslice.
152	*/
153	if (unlikely(p->policy == SCHED_FIFO)) {
154	expired_balance = 0;
155	- goto out;
156	+ goto out_unlock;
157	}
158
159	- spin_lock(&rq->lock);
160	debit = ns_diff(rq->timestamp_last_tick, p->timestamp);
161	p->ns_debit += debit;
162	if (p->ns_debit < NSJIFFY)
163	@@ -2696,7 +2747,7 @@ static int dependent_sleeper(const int t
164	task_t *smt_curr = smt_rq->curr;
165
166	/* Kernel threads do not participate in dependent sleeping */
167	- if (!p->mm \|\| !smt_curr->mm \|\| rt_task(p))
168	+ if (!p->mm \|\| !smt_curr->mm \|\| rt_task(p) \|\| iso_task(p))
169	goto check_smt_task;
170
171	/*
172	@@ -2723,7 +2774,7 @@ static int dependent_sleeper(const int t
173
174	check_smt_task:
175	if ((!smt_curr->mm && smt_curr != smt_rq->idle) \|\|
176	- rt_task(smt_curr))
177	+ rt_task(smt_curr) \|\| iso_task(smt_curr))
178	continue;
179	if (!p->mm) {
180	wakeup_busy_runqueue(smt_rq);
181	@@ -3525,9 +3576,19 @@ int sched_setscheduler(struct task_struc
182	{
183	int retval;
184	int queued, oldprio, oldpolicy = -1;
185	+ struct sched_param zero_param = { .sched_priority = 0 };
186	unsigned long flags;
187	runqueue_t *rq;
188
189	+ if (SCHED_RT(policy) && !capable(CAP_SYS_NICE)) {
190	+ /*
191	+ * If the caller requested an RT policy without having the
192	+ * necessary rights, we downgrade the policy to SCHED_ISO.
193	+ * We also set the parameter to zero to pass the checks.
194	+ */
195	+ policy = SCHED_ISO;
196	+ param = &zero_param;
197	+ }
198	recheck:
199	/* double check policy once rq lock held */
200	if (policy < 0)
201	@@ -4029,6 +4090,7 @@ asmlinkage long sys_sched_get_priority_m
202	break;
203	case SCHED_NORMAL:
204	case SCHED_BATCH:
205	+ case SCHED_ISO:
206	ret = 0;
207	break;
208	}
209	@@ -4053,6 +4115,7 @@ asmlinkage long sys_sched_get_priority_m
210	break;
211	case SCHED_NORMAL:
212	case SCHED_BATCH:
213	+ case SCHED_ISO:
214	ret = 0;
215	}
216	return ret;
217	@@ -5903,6 +5966,7 @@ void __init sched_init(void)
218	rq->nr_running = 0;
219	rq->cache_ticks = 0;
220	rq->preempted = 0;
221	+ rq->iso_ticks = 0;
222
223	#ifdef CONFIG_SMP
224	rq->sd = NULL;
225	Index: linux-2.6.16-ck1/kernel/sysctl.c
226	===================================================================
227	--- linux-2.6.16-ck1.orig/kernel/sysctl.c 2006-03-20 20:46:48.000000000 +1100
228	+++ linux-2.6.16-ck1/kernel/sysctl.c 2006-03-20 20:46:50.000000000 +1100
229	@@ -229,6 +229,11 @@ static ctl_table root_table[] = {
230	{ .ctl_name = 0 }
231	};
232
233	+/* Constants for minimum and maximum testing.
234	+ We use these as one-element integer vectors. */
235	+static int zero;
236	+static int one_hundred = 100;
237	+
238	static ctl_table kern_table[] = {
239	{
240	.ctl_name = KERN_OSTYPE,
241	@@ -639,6 +644,17 @@ static ctl_table kern_table[] = {
242	.mode = 0644,
243	.proc_handler = &proc_dointvec,
244	},
245	+ {
246	+ .ctl_name = KERN_ISO_CPU,
247	+ .procname = "iso_cpu",
248	+ .data = &sched_iso_cpu,
249	+ .maxlen = sizeof (int),
250	+ .mode = 0644,
251	+ .proc_handler = &proc_dointvec_minmax,
252	+ .strategy = &sysctl_intvec,
253	+ .extra1 = &zero,
254	+ .extra2 = &one_hundred,
255	+ },
256	#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
257	{
258	.ctl_name = KERN_UNKNOWN_NMI_PANIC,
259	@@ -702,12 +718,6 @@ static ctl_table kern_table[] = {
260	{ .ctl_name = 0 }
261	};
262
263	-/* Constants for minimum and maximum testing in vm_table.
264	- We use these as one-element integer vectors. */
265	-static int zero;
266	-static int one_hundred = 100;
267	-
268	-
269	static ctl_table vm_table[] = {
270	{
271	.ctl_name = VM_OVERCOMMIT_MEMORY,