From: Ingo Molnar <mingo@elte.hu>
      Nick Piggin <nickpiggin@yahoo.com.au>

sets cache_hot_time on x86. Activates sched-domains on SMP x86 too.


---

 25-akpm/arch/i386/kernel/smpboot.c   |   46 ++++++++++++++++++++++++++++++++++-
 25-akpm/include/asm-i386/processor.h |    8 +++---
 2 files changed, 50 insertions(+), 4 deletions(-)

diff -puN arch/i386/kernel/smpboot.c~sched-x86-cachehot-fix arch/i386/kernel/smpboot.c
--- 25/arch/i386/kernel/smpboot.c~sched-x86-cachehot-fix	2004-03-26 12:29:13.718863744 -0800
+++ 25-akpm/arch/i386/kernel/smpboot.c	2004-03-26 12:29:13.723862984 -0800
@@ -1148,9 +1148,11 @@ __init void arch_init_sched_domains(void
 
 		*phys_domain = SD_CPU_INIT;
 		phys_domain->span = nodemask;
+		phys_domain->cache_hot_time = cacheflush_time / 2;
 
 		*node_domain = SD_NODE_INIT;
 		node_domain->span = cpu_possible_map;
+		node_domain->cache_hot_time = cacheflush_time;
 	}
 
 	/* Set up CPU (sibling) groups */
@@ -1275,6 +1277,7 @@ __init void arch_init_sched_domains(void
 
 		*phys_domain = SD_CPU_INIT;
 		phys_domain->span = cpu_possible_map;
+		phys_domain->cache_hot_time = cacheflush_time / 2;
 	}
 
 	/* Set up CPU (sibling) groups */
@@ -1339,7 +1342,48 @@ __init void arch_init_sched_domains(void
 	}
 }
 #endif /* CONFIG_NUMA */
-#endif /* CONFIG_SCHED_SMT */
+#else /* !CONFIG_SCHED_SMT */
+
+static struct sched_group sched_group_cpus[NR_CPUS];
+
+__init void arch_init_sched_domains(void)
+{
+	int i;
+	struct sched_group *first_cpu = NULL, *last_cpu = NULL;
+
+	/* Set up domains */
+	for_each_cpu(i) {
+		struct sched_domain *cpu_sd = cpu_sched_domain(i);
+
+		*cpu_sd = SD_CPU_INIT;
+		cpu_sd->span = cpu_possible_map;
+		cpu_sd->cache_hot_time = cacheflush_time / 2;
+	}
+
+	/* Set up CPU groups */
+	for_each_cpu_mask(i, cpu_possible_map) {
+		struct sched_group *cpu = &sched_group_cpus[i];
+
+		cpus_clear(cpu->cpumask);
+		cpu_set(i, cpu->cpumask);
+		cpu->cpu_power = SCHED_LOAD_SCALE;
+
+		if (!first_cpu)
+			first_cpu = cpu;
+		if (last_cpu)
+			last_cpu->next = cpu;
+		last_cpu = cpu;
+	}
+	last_cpu->next = first_cpu;
+
+	mb();
+	for_each_cpu(i) {
+		struct sched_domain *cpu_sd = cpu_sched_domain(i);
+		cpu_sd->groups = &sched_group_cpus[i];
+	}
+}
+
+#endif
 
 /* These are wrappers to interface to the new boot process.  Someone
    who understands all this stuff should rewrite it properly. --RR 15/Jul/02 */
diff -puN include/asm-i386/processor.h~sched-x86-cachehot-fix include/asm-i386/processor.h
--- 25/include/asm-i386/processor.h~sched-x86-cachehot-fix	2004-03-26 12:29:13.719863592 -0800
+++ 25-akpm/include/asm-i386/processor.h	2004-03-26 12:29:13.724862832 -0800
@@ -646,9 +646,11 @@ extern inline void prefetchw(const void 
 
 extern void select_idle_routine(const struct cpuinfo_x86 *c);
 
-#ifdef CONFIG_SCHED_SMT
-#define ARCH_HAS_SCHED_DOMAIN
-#define ARCH_HAS_SCHED_WAKE_IDLE
+#ifdef CONFIG_SMP
+# define ARCH_HAS_SCHED_DOMAIN
+# ifdef CONFIG_SCHED_SMT
+#  define ARCH_HAS_SCHED_WAKE_IDLE
+# endif
 #endif
 
 #endif /* __ASM_I386_PROCESSOR_H */

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