* [Linux-ia64] Re: O(1) MQ scheduler J9 patch for IA64 -> K3 patch
2002-02-08 6:11 [Linux-ia64] Re: O(1) MQ scheduler J9 patch for IA64 David Mosberger
2002-02-08 6:37 ` William Lee Irwin III
2002-02-08 6:40 ` David Mosberger
@ 2002-02-08 17:37 ` Erich Focht
2 siblings, 0 replies; 4+ messages in thread
From: Erich Focht @ 2002-02-08 17:37 UTC (permalink / raw)
To: linux-ia64
[-- Attachment #1: Type: TEXT/PLAIN, Size: 1753 bytes --]
On Thu, 7 Feb 2002, David Mosberger wrote:
> Erich> I had to add a function smp_call_function_nowait which sends
> Erich> an IPI and returns immediately in order to get rid of a
> Erich> IA64-specific race condition when the mmu_context wraps
> Erich> around. Now it makes a very stable and fast impression,
> Erich> interactive work is even possible while doing a "hackbench
> Erich> 55" and ping flooding the machine... Tested on 2 CPU BigSur,
> Erich> 4 CPU LION, 16 CPU AzusA.
>
> Hmmh, I'm a bit worried that this is a fragile solution. It would
> break if there ever was a scenario where a task migrated from one CPU
> to another while the target CPU has interrupts disabled. I do not
> think this can happen with Ingo's current scheduler but I'd prefer a
> more robust solution.
>
> A somewhat cheesy solution might be to have a per-CPU flag that
> indicates whether a CPU should flush its TLB before switching to the
> next task. We could check for this in activate_mm(). Do you want to
> try this?
OK, I also feel better with the new solution. Didn't want to put it into
the runqueues because it really is an IA-64 problem. It's
architecture-specific and the CPU flags are in ia64_ctx. The context
wrapping is so seldom that the single lock protecting the CPU mask
shouldn't matter. But if somebody decides to use this mechanism generally
for flush_tlb_all() we'd have to change it...
Besides this: the attached patch is for the latest version of the
O(1) scheduler (K3). It has a different sys_sched_yield() from Ingo's
because that one has a problem with more than 8 CPUs. Also the
set_cpus_allowed() function has the limitation that it just works if the
current process tries to change its mask.
Best regards,
Erich
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diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kdb/kdba_bt.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kdb/kdba_bt.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kdb/kdba_bt.c Mon Feb 4 12:42:05 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kdb/kdba_bt.c Fri Feb 8 12:11:24 2002
@@ -197,7 +197,7 @@
}
#ifdef CONFIG_SMP
else if (task_has_cpu(p)) {
- sw = kdb_sw[p->processor];
+ sw = kdb_sw[p->cpu];
}
#endif
else {
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/entry.S 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/entry.S
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/entry.S Mon Feb 4 12:41:37 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/entry.S Fri Feb 8 12:11:24 2002
@@ -161,7 +161,8 @@
mov r8=r13 // return pointer to previously running task
mov r13=in0 // set "current" pointer
;;
-(p6) ssm psr.i // renable psr.i AFTER the ic bit is serialized
+//(p6) ssm psr.i // interrupt delivery should not be enabled
+ // with the new O(1) MQ scheduler
DO_LOAD_SWITCH_STACK
#ifdef CONFIG_SMP
@@ -170,7 +171,8 @@
br.ret.sptk.many rp // boogie on out in new context
.map:
- rsm psr.i | psr.ic
+ //rsm psr.i | psr.ic
+ rsm psr.ic
movl r25=PAGE_KERNEL
;;
srlz.d
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/irq_ia64.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/irq_ia64.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/irq_ia64.c Fri Nov 9 23:26:17 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/irq_ia64.c Fri Feb 8 12:11:24 2002
@@ -148,6 +148,14 @@
flags: SA_INTERRUPT,
name: "IPI"
};
+
+extern void smp_task_migration_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+
+static struct irqaction task_migration_irqaction = {
+ handler: smp_task_migration_interrupt,
+ flags: SA_INTERRUPT,
+ name: "Task migration"
+};
#endif
void
@@ -172,6 +180,7 @@
register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
#ifdef CONFIG_SMP
register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
+ register_percpu_irq(IA64_TASK_MIGRATION, &task_migration_irqaction);
#endif
platform_irq_init();
}
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/process.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/process.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/process.c Mon Feb 4 12:41:37 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/process.c Fri Feb 8 12:11:24 2002
@@ -125,9 +125,6 @@
cpu_idle (void *unused)
{
/* endless idle loop with no priority at all */
- init_idle();
- current->nice = 20;
- current->counter = -100;
while (1) {
@@ -136,11 +133,10 @@
min_xtp();
#endif
- while (!current->need_resched) {
+ if (!current->need_resched) {
#ifdef CONFIG_IA64_SGI_SN
snidle();
#endif
- continue;
}
#ifdef CONFIG_IA64_SGI_SN
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/setup.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/setup.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/setup.c Mon Feb 4 12:41:37 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/setup.c Fri Feb 8 12:11:24 2002
@@ -375,10 +375,10 @@
{
#ifdef CONFIG_SMP
# define lpj c->loops_per_jiffy
-# define cpu c->processor
+# define cpum c->processor
#else
# define lpj loops_per_jiffy
-# define cpu 0
+# define cpum 0
#endif
char family[32], features[128], *cp;
struct cpuinfo_ia64 *c = v;
@@ -417,7 +417,7 @@
"cpu MHz : %lu.%06lu\n"
"itc MHz : %lu.%06lu\n"
"BogoMIPS : %lu.%02lu\n\n",
- cpu, c->vendor, family, c->model, c->revision, c->archrev,
+ cpum, c->vendor, family, c->model, c->revision, c->archrev,
features, c->ppn, c->number,
c->proc_freq / 1000000, c->proc_freq % 1000000,
c->itc_freq / 1000000, c->itc_freq % 1000000,
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/smp.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/smp.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/smp.c Mon Feb 4 12:42:05 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/smp.c Fri Feb 8 12:42:35 2002
@@ -200,6 +200,42 @@
}
void
+smp_send_reschedule_all(void)
+{
+ send_IPI_all(IA64_IPI_RESCHEDULE);
+}
+
+static spinlock_t migration_lock = SPIN_LOCK_UNLOCKED;
+static task_t *new_task;
+
+
+/*
+ * This function sends a 'task migration' IPI to another CPU.
+ * Must be called from syscall contexts, with interrupts *enabled*.
+ */
+void smp_migrate_task(int cpu, task_t *p)
+{
+ /*
+ * The target CPU will unlock the migration spinlock:
+ */
+ spin_lock(&migration_lock);
+ new_task = p;
+ platform_send_ipi(cpu, IA64_TASK_MIGRATION, IA64_IPI_DM_INT, 0);
+}
+
+/*
+ * Task migration callback.
+ */
+asmlinkage void smp_task_migration_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ task_t *p;
+
+ p = new_task;
+ spin_unlock(&migration_lock);
+ sched_task_migrated(p);
+}
+
+void
smp_flush_tlb_all (void)
{
smp_call_function ((void (*)(void *))__flush_tlb_all,0,1,1);
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/smpboot.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/smpboot.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/smpboot.c Mon Feb 4 12:41:37 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/smpboot.c Fri Feb 8 12:11:24 2002
@@ -356,6 +356,7 @@
local_irq_enable();
calibrate_delay();
local_cpu_data->loops_per_jiffy = loops_per_jiffy;
+ ia64_disable_timer();
/*
* Allow the master to continue.
*/
@@ -379,7 +380,8 @@
Dprintk("CPU %d is set to go.\n", smp_processor_id());
while (!atomic_read(&smp_commenced))
;
-
+ /* reenable timer interrupts */
+ ia64_cpu_local_tick();
Dprintk("CPU %d is starting idle.\n", smp_processor_id());
return cpu_idle();
}
@@ -416,11 +418,10 @@
if (!idle)
panic("No idle process for CPU %d", cpu);
- task_set_cpu(idle, cpu); /* we schedule the first task manually */
+ init_idle(idle, cpu);
ia64_cpu_to_sapicid[cpu] = sapicid;
- del_from_runqueue(idle);
unhash_process(idle);
init_tasks[cpu] = idle;
@@ -481,8 +482,7 @@
printk("Boot processor id 0x%x/0x%x\n", 0, boot_cpu_id);
global_irq_holder = 0;
- current->processor = 0;
- init_idle();
+ current->cpu = 0;
/*
* If SMP should be disabled, then really disable it!
@@ -569,3 +569,9 @@
smp_num_cpus = 1;
}
}
+
+/* Number of ticks we consider an idle tasks still cache-hot.
+ * For Itanium: with 1GB/s bandwidth we need 4ms to fill up 4MB L3 cache...
+ * So let's try 10 ticks.
+ */
+unsigned long cache_decay_ticks=10;
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/time.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/time.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/kernel/time.c Fri Nov 9 23:26:17 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/kernel/time.c Fri Feb 8 12:11:24 2002
@@ -209,7 +209,7 @@
/*
* Encapsulate access to the itm structure for SMP.
*/
-void __init
+void
ia64_cpu_local_tick (void)
{
int cpu = smp_processor_id();
@@ -298,3 +298,9 @@
efi_gettimeofday((struct timeval *) &xtime);
ia64_init_itm();
}
+
+void __init ia64_disable_timer(void)
+{
+ ia64_set_itv(IA64_TIMER_VECTOR | IA64_TIMER_MASK);
+}
+
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/mm/fault.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/mm/fault.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/mm/fault.c Fri Nov 9 23:26:17 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/mm/fault.c Fri Feb 8 12:11:24 2002
@@ -194,8 +194,7 @@
out_of_memory:
up_read(&mm->mmap_sem);
if (current->pid == 1) {
- current->policy |= SCHED_YIELD;
- schedule();
+ yield();
down_read(&mm->mmap_sem);
goto survive;
}
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/mm/tlb.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/mm/tlb.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/mm/tlb.c Fri Nov 9 23:26:17 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/mm/tlb.c Fri Feb 8 13:06:21 2002
@@ -37,7 +37,8 @@
lock: SPIN_LOCK_UNLOCKED,
next: 1,
limit: (1 << 15) - 1, /* start out with the safe (architected) limit */
- max_ctx: ~0U
+ max_ctx: ~0U,
+ flush: 0UL
};
/*
@@ -76,7 +77,9 @@
ia64_ctx.limit = tsk_context;
}
read_unlock(&tasklist_lock);
- flush_tlb_all();
+ //flush_tlb_all(); /* potential race condition with O(1) scheduler [EF] */
+ ia64_ctx.flush = ((1<<smp_num_cpus) - 1) & ~(1UL<<smp_processor_id());
+ __flush_tlb_all();
}
static inline void
diff -urN 2.4.17-ia64-kdbv2.1-K3/arch/ia64/tools/print_offsets.c 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/tools/print_offsets.c
--- 2.4.17-ia64-kdbv2.1-K3/arch/ia64/tools/print_offsets.c Fri Nov 9 23:26:17 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/arch/ia64/tools/print_offsets.c Fri Feb 8 12:11:24 2002
@@ -54,7 +54,7 @@
{ "IA64_TASK_PTRACE_OFFSET", offsetof (struct task_struct, ptrace) },
{ "IA64_TASK_SIGPENDING_OFFSET", offsetof (struct task_struct, sigpending) },
{ "IA64_TASK_NEED_RESCHED_OFFSET", offsetof (struct task_struct, need_resched) },
- { "IA64_TASK_PROCESSOR_OFFSET", offsetof (struct task_struct, processor) },
+ { "IA64_TASK_PROCESSOR_OFFSET", offsetof (struct task_struct, cpu) },
{ "IA64_TASK_THREAD_OFFSET", offsetof (struct task_struct, thread) },
{ "IA64_TASK_THREAD_KSP_OFFSET", offsetof (struct task_struct, thread.ksp) },
#ifdef CONFIG_PERFMON
diff -urN 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/bitops.h 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/bitops.h
--- 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/bitops.h Mon Feb 4 12:41:38 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/bitops.h Fri Feb 8 12:11:24 2002
@@ -280,6 +280,20 @@
return result;
}
+/**
+ * __ffs - find first bit in a 64 bit long.
+ *
+ * Undefined if no bit exists, so code should check against 0 first.
+ */
+static inline unsigned long
+__ffs (unsigned long x)
+{
+ unsigned long result;
+
+ __asm__ ("popcnt %0=%1" : "=r" (result) : "r" (~x & (x - 1)));
+ return result;
+}
+
#ifdef __KERNEL__
/*
@@ -357,6 +371,8 @@
tmp = *p;
found_first:
tmp |= ~0UL << size;
+ if (tmp == ~0UL) /* Are any bits zero? */
+ return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
@@ -366,8 +382,52 @@
*/
#define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0)
+/*
+ * Find next bit in a bitmap reasonably efficiently..
+ */
+static inline int
+find_next_bit (void *addr, unsigned long size, unsigned long offset)
+{
+ unsigned long *p = ((unsigned long *) addr) + (offset >> 6);
+ unsigned long result = offset & ~63UL;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 63UL;
+ if (offset) {
+ tmp = *(p++);
+ tmp &= ~0UL << offset;
+ if (size < 64)
+ goto found_first;
+ if (tmp)
+ goto found_middle;
+ size -= 64;
+ result += 64;
+ }
+ while (size & ~63UL) {
+ if ((tmp = *(p++)))
+ goto found_middle;
+ result += 64;
+ size -= 64;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+found_first:
+ tmp &= ~0UL >> (64-size);
+ if (tmp == 0UL) /* Are any bits set? */
+ return result + size; /* Nope. */
+found_middle:
+ return result + __ffs(tmp);
+}
+
+#define find_first_bit(addr, size) find_next_bit((addr), (size), 0)
+
#ifdef __KERNEL__
+#define __clear_bit(nr, addr) clear_bit(nr, addr)
#define ext2_set_bit test_and_set_bit
#define ext2_clear_bit test_and_clear_bit
#define ext2_test_bit test_bit
diff -urN 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/hw_irq.h 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/hw_irq.h
--- 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/hw_irq.h Tue Jul 31 19:30:09 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/hw_irq.h Fri Feb 8 12:11:24 2002
@@ -49,6 +49,7 @@
#define IA64_PERFMON_VECTOR 0xee /* performanc monitor interrupt vector */
#define IA64_TIMER_VECTOR 0xef /* use highest-prio group 15 interrupt for timer */
#define IA64_MCA_WAKEUP_VECTOR 0xf0 /* MCA wakeup (must be >MCA_RENDEZ_VECTOR) */
+#define IA64_TASK_MIGRATION 0xfb /* task migration interrupt vector */
#define IA64_IPI_RESCHEDULE 0xfd /* SMP reschedule */
#define IA64_IPI_VECTOR 0xfe /* inter-processor interrupt vector */
@@ -65,6 +66,9 @@
IA64_IPI_DM_EXTINT = 0x7, /* pend an 8259-compatible interrupt. */
};
+/* bit for masking and discarding timer interrupts on IA64 */
+#define IA64_TIMER_MASK (1<<16)
+
extern __u8 isa_irq_to_vector_map[16];
#define isa_irq_to_vector(x) isa_irq_to_vector_map[(x)]
diff -urN 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/mmu_context.h 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/mmu_context.h
--- 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/mmu_context.h Fri Nov 9 23:26:17 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/mmu_context.h Fri Feb 8 12:56:09 2002
@@ -33,6 +33,9 @@
unsigned int next; /* next context number to use */
unsigned int limit; /* next >= limit => must call wrap_mmu_context() */
unsigned int max_ctx; /* max. context value supported by all CPUs */
+ unsigned long flush; /* CPU mask for those which have to perform a
+ * local TLB flush before switching the context.
+ */
};
extern struct ia64_ctx ia64_ctx;
@@ -44,6 +47,25 @@
{
}
+/*
+ * When the context counter wraps around all TLBs need to be flushed because
+ * an old context number might have been reused. This is signalled by a bit
+ * set in ia64_ctx.flush, which is checked in the routine below. Called by
+ * activate_mm(). <efocht@ess.nec.de>
+ */
+static inline void
+delayed_tlb_flush (void)
+{
+ extern void __flush_tlb_all (void);
+
+ if (unlikely(ia64_ctx.flush & (1<<smp_processor_id()))) {
+ spin_lock(&ia64_ctx.lock);
+ __flush_tlb_all();
+ ia64_ctx.flush &= ~(1<<smp_processor_id());
+ spin_unlock(&ia64_ctx.lock);
+ }
+}
+
static inline void
get_new_mmu_context (struct mm_struct *mm)
{
@@ -113,11 +135,28 @@
* We may get interrupts here, but that's OK because interrupt
* handlers cannot touch user-space.
*/
+ delayed_tlb_flush();
ia64_set_kr(IA64_KR_PT_BASE, __pa(next->pgd));
get_mmu_context(next);
reload_context(next);
}
+/*
+ * Needed for the O(1) MQ scheduler.
+ */
+#if MAX_PRIO >= 192
+# error update this function. */
+#endif
+
+static inline int sched_find_first_bit(unsigned long *b)
+{
+ if (unlikely(b[0]))
+ return __ffs(b[0]);
+ if (b[1])
+ return 64 + __ffs(b[1]);
+ return __ffs(b[2]) + 128;
+}
+
#define switch_mm(prev_mm,next_mm,next_task,cpu) activate_mm(prev_mm, next_mm)
# endif /* ! __ASSEMBLY__ */
diff -urN 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/pgalloc.h 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/pgalloc.h
--- 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/pgalloc.h Tue Feb 5 15:33:18 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/pgalloc.h Fri Feb 8 12:11:24 2002
@@ -160,9 +160,12 @@
#ifdef CONFIG_SMP
extern void smp_flush_tlb_all (void);
+ extern void smp_flush_tlb_all_nowait (void);
# define flush_tlb_all() smp_flush_tlb_all()
+# define flush_tlb_all_nowait() smp_flush_tlb_all_nowait()
#else
# define flush_tlb_all() __flush_tlb_all()
+# define flush_tlb_all_nowait() __flush_tlb_all()
#endif
/*
diff -urN 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/smp.h 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/smp.h
--- 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/smp.h Fri Nov 9 23:26:17 2001
+++ 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/smp.h Fri Feb 8 12:11:24 2002
@@ -27,7 +27,7 @@
#define SMP_IRQ_REDIRECTION (1 << 0)
#define SMP_IPI_REDIRECTION (1 << 1)
-#define smp_processor_id() (current->processor)
+#define smp_processor_id() (current->cpu)
extern struct smp_boot_data {
int cpu_count;
@@ -48,6 +48,9 @@
extern unsigned long ap_wakeup_vector;
+extern void smp_send_reschedule(int cpu);
+extern void smp_send_reschedule_all(void);
+
/*
* Function to map hard smp processor id to logical id. Slow, so
* don't use this in performance-critical code.
@@ -110,12 +113,6 @@
#define NO_PROC_ID 0xffffffff /* no processor magic marker */
-/*
- * Extra overhead to move a task from one cpu to another (due to TLB and cache misses).
- * Expressed in "negative nice value" units (larger number means higher priority/penalty).
- */
-#define PROC_CHANGE_PENALTY 20
-
extern void __init init_smp_config (void);
extern void smp_do_timer (struct pt_regs *regs);
diff -urN 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/spinlock.h 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/spinlock.h
--- 2.4.17-ia64-kdbv2.1-K3/include/asm-ia64/spinlock.h Mon Feb 4 12:41:39 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/include/asm-ia64/spinlock.h Fri Feb 8 12:11:24 2002
@@ -84,7 +84,7 @@
"mov r29 = 1\n" \
";;\n" \
"1:\n" \
- "ld4.bias r2 = [%0]\n" \
+ "ld4 r2 = [%0]\n" \
";;\n" \
"cmp4.eq p0,p7 = r0,r2\n" \
"(p7) br.cond.spnt.few 1b \n" \
diff -urN 2.4.17-ia64-kdbv2.1-K3/include/linux/smp.h 2.4.17-ia64-kdbv2.1-K3ia64/include/linux/smp.h
--- 2.4.17-ia64-kdbv2.1-K3/include/linux/smp.h Fri Feb 8 12:02:06 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/include/linux/smp.h Fri Feb 8 12:11:24 2002
@@ -24,12 +24,6 @@
extern void smp_send_stop(void);
/*
- * sends a 'reschedule' event to another CPU:
- */
-extern void FASTCALL(smp_send_reschedule(int cpu));
-
-
-/*
* Boot processor call to load the other CPU's
*/
extern void smp_boot_cpus(void);
diff -urN 2.4.17-ia64-kdbv2.1-K3/kdb/kdbmain.c 2.4.17-ia64-kdbv2.1-K3ia64/kdb/kdbmain.c
--- 2.4.17-ia64-kdbv2.1-K3/kdb/kdbmain.c Mon Feb 4 12:41:04 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/kdb/kdbmain.c Fri Feb 8 12:11:24 2002
@@ -2344,7 +2344,7 @@
for_each_task(p) {
kdb_printf("0x%p %08d %08d %1.1d %3.3d %s 0x%p%c%s\n",
(void *)p, p->pid, p->p_pptr->pid,
- task_has_cpu(p), p->processor,
+ task_has_cpu(p), p->cpu,
(p->state == 0)?"run ":(p->state>0)?"stop":"unrn",
(void *)(&p->thread),
(p == current) ? '*': ' ',
diff -urN 2.4.17-ia64-kdbv2.1-K3/kernel/printk.c 2.4.17-ia64-kdbv2.1-K3ia64/kernel/printk.c
--- 2.4.17-ia64-kdbv2.1-K3/kernel/printk.c Fri Feb 8 12:02:06 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/kernel/printk.c Fri Feb 8 12:11:24 2002
@@ -25,6 +25,8 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/interrupt.h> /* For in_interrupt() */
+#include <linux/config.h>
+#include <linux/delay.h>
#include <asm/uaccess.h>
diff -urN 2.4.17-ia64-kdbv2.1-K3/kernel/sched.c 2.4.17-ia64-kdbv2.1-K3ia64/kernel/sched.c
--- 2.4.17-ia64-kdbv2.1-K3/kernel/sched.c Fri Feb 8 12:02:06 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/kernel/sched.c Fri Feb 8 12:21:07 2002
@@ -154,6 +154,15 @@
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
#define rt_task(p) ((p)->prio < MAX_RT_PRIO)
+/* needed on IA64, arch/ia64/kernel/head.S relies on it (EF) */
+struct task_struct * init_tasks[NR_CPUS] __initdata = {&init_task, };
+
+/* needed in kdb (EF) */
+int task_has_cpu(task_t *p)
+{
+ return (p == task_rq(p)->curr);
+}
+
static inline runqueue_t *lock_task_rq(task_t *p, unsigned long *flags)
{
struct runqueue *__rq;
@@ -671,7 +680,7 @@
task_t *p = current;
if (p == rq->idle) {
- if (local_bh_count(cpu) || local_irq_count(cpu) > 1)
+ if (really_local_bh_count() || really_local_irq_count() > 1)
kstat.per_cpu_system[cpu] += system;
#if CONFIG_SMP
idle_tick();
@@ -974,16 +983,16 @@
p->cpus_allowed = new_mask;
/*
- * Can the task run on the current CPU? If not then
+ * Can the task run on its current CPU? If not then
* migrate the process off to a proper CPU.
*/
- if (new_mask & (1UL << smp_processor_id()))
+ if (new_mask & (1UL << p->cpu))
return;
#if CONFIG_SMP
- current->state = TASK_UNINTERRUPTIBLE;
- smp_migrate_task(__ffs(new_mask), current);
-
- schedule();
+ p->state = TASK_UNINTERRUPTIBLE;
+ smp_migrate_task(__ffs(new_mask), p);
+ if (p == current)
+ schedule();
#endif
}
@@ -1229,64 +1238,26 @@
asmlinkage long sys_sched_yield(void)
{
- task_t *prev = current, *next;
runqueue_t *rq = this_rq();
prio_array_t *array;
- list_t *queue;
-
- if (unlikely(prev->state != TASK_RUNNING)) {
- schedule();
- return 0;
- }
- release_kernel_lock(prev, smp_processor_id());
- prev->sleep_timestamp = jiffies;
- /*
- * Decrease the yielding task's priority by one, to avoid
- * livelocks. This priority loss is temporary, it's recovered
- * once the current timeslice expires.
- *
- * If priority is already MAX_PRIO-1 then we still
- * roundrobin the task within the runlist.
- */
+
+ /*
+ * Decrease the yielding task's priority by one, to avoid
+ * livelocks. This priority loss is temporary, it's recovered
+ * once the current timeslice expires.
+ *
+ * If priority is already MAX_PRIO-1 then we still
+ * roundrobin the task within the runlist.
+ */
spin_lock_irq(&rq->lock);
array = current->array;
- /*
- * If the task has reached maximum priority (or is a RT task)
- * then just requeue the task to the end of the runqueue:
- */
- if (likely(current->prio == MAX_PRIO-1 || rt_task(current))) {
- list_del(¤t->run_list);
- list_add_tail(¤t->run_list, array->queue + current->prio);
- } else {
- list_del(¤t->run_list);
- if (list_empty(array->queue + current->prio))
- __clear_bit(current->prio, array->bitmap);
- current->prio++;
- list_add_tail(¤t->run_list, array->queue + current->prio);
- __set_bit(current->prio, array->bitmap);
- }
- /*
- * Context-switch manually. This is equivalent to
- * calling schedule(), but faster, because yield()
- * knows lots of things that can be optimized away
- * from the generic scheduler path:
- */
- queue = array->queue + sched_find_first_bit(array->bitmap);
- next = list_entry(queue->next, task_t, run_list);
- prefetch(next);
-
- prev->need_resched = 0;
- if (likely(prev != next)) {
- rq->nr_switches++;
- rq->curr = next;
- context_switch(prev, next);
- barrier();
- rq = this_rq();
- }
+ dequeue_task(current, array);
+ if (likely(!rt_task(current)))
+ if (current->prio < MAX_PRIO-1)
+ current->prio++;
+ enqueue_task(current, array);
spin_unlock_irq(&rq->lock);
-
- reacquire_kernel_lock(current);
-
+ schedule();
return 0;
}
diff -urN 2.4.17-ia64-kdbv2.1-K3/kernel/timer.c 2.4.17-ia64-kdbv2.1-K3ia64/kernel/timer.c
--- 2.4.17-ia64-kdbv2.1-K3/kernel/timer.c Fri Feb 8 12:02:06 2002
+++ 2.4.17-ia64-kdbv2.1-K3ia64/kernel/timer.c Fri Feb 8 12:11:24 2002
@@ -584,18 +584,7 @@
int cpu = smp_processor_id(), system = user_tick ^ 1;
update_one_process(p, user_tick, system, cpu);
- if (p->pid) {
- if (--p->counter <= 0) {
- p->counter = 0;
- p->need_resched = 1;
- }
- if (p->nice > 0)
- kstat.per_cpu_nice[cpu] += user_tick;
- else
- kstat.per_cpu_user[cpu] += user_tick;
- kstat.per_cpu_system[cpu] += system;
- } else if (really_local_bh_count() || really_local_irq_count() > 1)
- kstat.per_cpu_system[cpu] += system;
+ scheduler_tick(user_tick, system);
}
/*
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