From: Nick Piggin <piggin@cyberone.com.au>
This is a (somewhat) trivial patch which converts cpu_sibling_map from an
array of CPUs to an array of cpumasks. Needed for >2 siblings per package,
but it actually can simplify code as it allows the cpu_sibling_map to be
set up even when there is 1 sibling per package. Intel want this, I use it
in the next patch to build scheduling domains for the P4 HT.
---
25-akpm/arch/i386/kernel/cpu/cpufreq/p4-clockmod.c | 9 ----
25-akpm/arch/i386/kernel/io_apic.c | 19 ++++++---
25-akpm/arch/i386/kernel/smpboot.c | 40 +++++++++++----------
25-akpm/arch/i386/oprofile/op_model_p4.c | 7 +--
25-akpm/include/asm-i386/smp.h | 2 -
5 files changed, 37 insertions(+), 40 deletions(-)
diff -puN arch/i386/kernel/cpu/cpufreq/p4-clockmod.c~sched-sibling-map-to-cpumask arch/i386/kernel/cpu/cpufreq/p4-clockmod.c
--- 25/arch/i386/kernel/cpu/cpufreq/p4-clockmod.c~sched-sibling-map-to-cpumask Wed Feb 4 12:29:57 2004
+++ 25-akpm/arch/i386/kernel/cpu/cpufreq/p4-clockmod.c Wed Feb 4 12:29:57 2004
@@ -68,14 +68,7 @@ static int cpufreq_p4_setdc(unsigned int
cpus_allowed = current->cpus_allowed;
/* only run on CPU to be set, or on its sibling */
- affected_cpu_map = cpumask_of_cpu(cpu);
-#ifdef CONFIG_X86_HT
- hyperthreading = ((cpu_has_ht) && (smp_num_siblings == 2));
- if (hyperthreading) {
- sibling = cpu_sibling_map[cpu];
- cpu_set(sibling, affected_cpu_map);
- }
-#endif
+ affected_cpu_map = cpu_sibling_map[cpu];
set_cpus_allowed(current, affected_cpu_map);
BUG_ON(!cpu_isset(smp_processor_id(), affected_cpu_map));
diff -puN arch/i386/kernel/io_apic.c~sched-sibling-map-to-cpumask arch/i386/kernel/io_apic.c
--- 25/arch/i386/kernel/io_apic.c~sched-sibling-map-to-cpumask Wed Feb 4 12:29:57 2004
+++ 25-akpm/arch/i386/kernel/io_apic.c Wed Feb 4 12:29:57 2004
@@ -317,8 +317,7 @@ struct irq_cpu_info {
#define IRQ_ALLOWED(cpu, allowed_mask) cpu_isset(cpu, allowed_mask)
-#define CPU_TO_PACKAGEINDEX(i) \
- ((physical_balance && i > cpu_sibling_map[i]) ? cpu_sibling_map[i] : i)
+#define CPU_TO_PACKAGEINDEX(i) (first_cpu(cpu_sibling_map[i]))
#define MAX_BALANCED_IRQ_INTERVAL (5*HZ)
#define MIN_BALANCED_IRQ_INTERVAL (HZ/2)
@@ -401,6 +400,7 @@ static void do_irq_balance(void)
unsigned long max_cpu_irq = 0, min_cpu_irq = (~0);
unsigned long move_this_load = 0;
int max_loaded = 0, min_loaded = 0;
+ int load;
unsigned long useful_load_threshold = balanced_irq_interval + 10;
int selected_irq;
int tmp_loaded, first_attempt = 1;
@@ -452,7 +452,7 @@ static void do_irq_balance(void)
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_online(i))
continue;
- if (physical_balance && i > cpu_sibling_map[i])
+ if (i != CPU_TO_PACKAGEINDEX(i))
continue;
if (min_cpu_irq > CPU_IRQ(i)) {
min_cpu_irq = CPU_IRQ(i);
@@ -471,7 +471,7 @@ tryanothercpu:
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_online(i))
continue;
- if (physical_balance && i > cpu_sibling_map[i])
+ if (i != CPU_TO_PACKAGEINDEX(i))
continue;
if (max_cpu_irq <= CPU_IRQ(i))
continue;
@@ -551,9 +551,14 @@ tryanotherirq:
* We seek the least loaded sibling by making the comparison
* (A+B)/2 vs B
*/
- if (physical_balance && (CPU_IRQ(min_loaded) >> 1) >
- CPU_IRQ(cpu_sibling_map[min_loaded]))
- min_loaded = cpu_sibling_map[min_loaded];
+ load = CPU_IRQ(min_loaded) >> 1;
+ for_each_cpu_mask(j, cpu_sibling_map[min_loaded]) {
+ if (load > CPU_IRQ(j)) {
+ /* This won't change cpu_sibling_map[min_loaded] */
+ load = CPU_IRQ(j);
+ min_loaded = j;
+ }
+ }
cpus_and(allowed_mask, cpu_online_map, irq_affinity[selected_irq]);
target_cpu_mask = cpumask_of_cpu(min_loaded);
diff -puN arch/i386/kernel/smpboot.c~sched-sibling-map-to-cpumask arch/i386/kernel/smpboot.c
--- 25/arch/i386/kernel/smpboot.c~sched-sibling-map-to-cpumask Wed Feb 4 12:29:57 2004
+++ 25-akpm/arch/i386/kernel/smpboot.c Wed Feb 4 12:29:57 2004
@@ -934,7 +934,7 @@ static int boot_cpu_logical_apicid;
/* Where the IO area was mapped on multiquad, always 0 otherwise */
void *xquad_portio;
-int cpu_sibling_map[NR_CPUS] __cacheline_aligned;
+cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned;
static void __init smp_boot_cpus(unsigned int max_cpus)
{
@@ -1080,32 +1080,34 @@ static void __init smp_boot_cpus(unsigne
Dprintk("Boot done.\n");
/*
- * If Hyper-Threading is avaialble, construct cpu_sibling_map[], so
- * that we can tell the sibling CPU efficiently.
+ * construct cpu_sibling_map[], so that we can tell sibling CPUs
+ * efficiently.
*/
- if (cpu_has_ht && smp_num_siblings > 1) {
- for (cpu = 0; cpu < NR_CPUS; cpu++)
- cpu_sibling_map[cpu] = NO_PROC_ID;
-
- for (cpu = 0; cpu < NR_CPUS; cpu++) {
- int i;
- if (!cpu_isset(cpu, cpu_callout_map))
- continue;
+ for (cpu = 0; cpu < NR_CPUS; cpu++)
+ cpu_sibling_map[cpu] = CPU_MASK_NONE;
+
+ for (cpu = 0; cpu < NR_CPUS; cpu++) {
+ int siblings = 0;
+ int i;
+ if (!cpu_isset(cpu, cpu_callout_map))
+ continue;
+ if (smp_num_siblings > 1) {
for (i = 0; i < NR_CPUS; i++) {
- if (i == cpu || !cpu_isset(i, cpu_callout_map))
+ if (!cpu_isset(i, cpu_callout_map))
continue;
if (phys_proc_id[cpu] == phys_proc_id[i]) {
- cpu_sibling_map[cpu] = i;
- printk("cpu_sibling_map[%d] = %d\n", cpu, cpu_sibling_map[cpu]);
- break;
+ siblings++;
+ cpu_set(i, cpu_sibling_map[cpu]);
}
}
- if (cpu_sibling_map[cpu] == NO_PROC_ID) {
- smp_num_siblings = 1;
- printk(KERN_WARNING "WARNING: No sibling found for CPU %d.\n", cpu);
- }
+ } else {
+ siblings++;
+ cpu_set(cpu, cpu_sibling_map[cpu]);
}
+
+ if (siblings != smp_num_siblings)
+ printk(KERN_WARNING "WARNING: %d siblings found for CPU%d, should be %d\n", siblings, cpu, smp_num_siblings);
}
smpboot_setup_io_apic();
diff -puN arch/i386/oprofile/op_model_p4.c~sched-sibling-map-to-cpumask arch/i386/oprofile/op_model_p4.c
--- 25/arch/i386/oprofile/op_model_p4.c~sched-sibling-map-to-cpumask Wed Feb 4 12:29:57 2004
+++ 25-akpm/arch/i386/oprofile/op_model_p4.c Wed Feb 4 12:29:57 2004
@@ -382,11 +382,8 @@ static struct p4_event_binding p4_events
static unsigned int get_stagger(void)
{
#ifdef CONFIG_SMP
- int cpu;
- if (smp_num_siblings > 1) {
- cpu = smp_processor_id();
- return (cpu_sibling_map[cpu] > cpu) ? 0 : 1;
- }
+ int cpu = smp_processor_id();
+ return (cpu != first_cpu(cpu_sibling_map[cpu]));
#endif
return 0;
}
diff -puN include/asm-i386/smp.h~sched-sibling-map-to-cpumask include/asm-i386/smp.h
--- 25/include/asm-i386/smp.h~sched-sibling-map-to-cpumask Wed Feb 4 12:29:57 2004
+++ 25-akpm/include/asm-i386/smp.h Wed Feb 4 12:29:57 2004
@@ -34,7 +34,7 @@
extern void smp_alloc_memory(void);
extern int pic_mode;
extern int smp_num_siblings;
-extern int cpu_sibling_map[];
+extern cpumask_t cpu_sibling_map[];
extern void smp_flush_tlb(void);
extern void smp_message_irq(int cpl, void *dev_id, struct pt_regs *regs);
_