[PATCH] Isolated sched domains for 2.6.8-rc2-mm1

From: Dimitri Sivanich (sivanich_at_sgi.com)
Date: 07/30/04

  • Next message: Andi Kleen: "Re: [PATCH] Improve pci_alloc_consistent wrapper on preemptive kernels" 
    Date:	Fri, 30 Jul 2004 12:46:51 -0500
To: Ingo Molnar <mingo@elte.hu>, Nick Piggin <nickpiggin@yahoo.com.au>, Jesse Barnes <jbarnes@engr.sgi.com>

    Hi all,

    Here's a version of the isolated scheduler domain code that I mentioned in an
    RFC on 7/22. This patch applies on top of 2.6.8-rc2-mm1 (to include all of
    the new arch_init_sched_domain code). This patch also contains the 2 line
    fix to remove the check of first_cpu(sd->groups->cpumask)) that Jesse
    sent in earlier.

    Note that this has not been tested with CONFIG_SCHED_SMT. I hope that
    my handling of those instances is OK.

    Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>

    Index: linux/kernel/sched.c
    ===================================================================
    --- linux.orig/kernel/sched.c 2004-07-30 09:38:57.000000000 -0500
    +++ linux/kernel/sched.c 2004-07-30 12:03:24.000000000 -0500
    @@ -3714,6 +3714,31 @@ __init static int cpu_to_node_group(int
     }
     #endif
     
    +/* Groups for isolated scheduling domains */
    +static struct sched_group sched_group_isolated[NR_CPUS];
    +__init static int cpu_to_isolated_group(int cpu)
    +{
    + return cpu;
    +}
    +
    +cpumask_t __initdata cpu_isolated_map = CPU_MASK_NONE; /* cpus with isolated domains */
    +
    +/* Setup the mask of cpus configured for isolated domains */
    +static int __init
    +isolated_cpu_setup(char *str)
    +{
    + int ints[NR_CPUS], i;
    +
    + str = get_options(str, ARRAY_SIZE(ints), ints);
    + cpus_clear(cpu_isolated_map);
    + for (i=1; i<=ints[0]; i++) {
    + cpu_set(ints[i], cpu_isolated_map);
    + }
    + return 1;
    +}
    +
    +__setup ("isolcpus=", isolated_cpu_setup);
    +
     /*
      * init_sched_build_groups takes an array of groups, the cpumask we wish
      * to span, and a pointer to a function which identifies what group a CPU
    @@ -3762,21 +3787,52 @@ __init static void init_sched_build_grou
     __init static void arch_init_sched_domains(void)
     {
             int i;
    + cpumask_t cpu_default_map;
    +
    + /*
    + * Setup mask for cpus without special case scheduling requirements.
    + * For now this just excludes isolated cpus, but could be used to
    + * exclude other special cases in the future.
    + */
    + cpus_complement(cpu_default_map, cpu_isolated_map);
    + cpus_and(cpu_default_map, cpu_default_map, cpu_possible_map);
     
             /* Set up domains */
             for_each_cpu(i) {
                     int group;
                     struct sched_domain *sd = NULL, *p;
                     cpumask_t nodemask = node_to_cpumask(cpu_to_node(i));
    + cpus_and(nodemask, nodemask, cpu_default_map);
     
    -#ifdef CONFIG_NUMA
    - if (i != first_cpu(sd->groups->cpumask))
    + /*
    + * Set up isolated domains.
    + * Unlike those of other cpus, the domains and groups are
    + * single level, and span a single cpu.
    + */
    + if (cpu_isset(i, cpu_isolated_map)) {
    +#ifdef CONFIG_SCHED_SMT
    + sd = &per_cpu(cpu_domains, i);
    +#else
    + sd = &per_cpu(phys_domains, i);
    +#endif
    + group = cpu_to_isolated_group(i);
    + *sd = SD_CPU_INIT;
    + cpu_set(i, sd->span);
    + sd->balance_interval = INT_MAX; /* Don't balance */
    + sd->flags = 0; /* Avoid WAKE_ */
    + sd->groups = &sched_group_isolated[group];
    + printk(KERN_INFO "Setting up cpu %d isolated.\n", i);
    + /* Single level, so continue with next cpu */
                             continue;
    + }
    +
    +#ifdef CONFIG_NUMA
                     sd = &per_cpu(node_domains, i);
                     group = cpu_to_node_group(i);
                     *sd = SD_NODE_INIT;
                     /* FIXME: should be multilevel, in arch code */
                     sd->span = sched_domain_node_span(i, SD_NODES_PER_DOMAIN);
    + cpus_and(sd->span, sd->span, cpu_default_map);
                     sd->groups = &sched_group_nodes[group];
     #endif
     
    @@ -3794,6 +3850,7 @@ __init static void arch_init_sched_domai
                     group = cpu_to_cpu_group(i);
                     *sd = SD_SIBLING_INIT;
                     sd->span = cpu_sibling_map[i];
    + cpus_and(sd->span, sd->span, cpu_default_map);
                     sd->parent = p;
                     sd->groups = &sched_group_cpus[group];
     #endif
    @@ -3802,19 +3859,30 @@ __init static void arch_init_sched_domai
     #ifdef CONFIG_SCHED_SMT
             /* Set up CPU (sibling) groups */
             for_each_cpu(i) {
    - if (i != first_cpu(cpu_sibling_map[i]))
    + cpumask_t this_sibling_map = cpu_sibling_map[i];
    + cpus_and(this_sibling_map, this_sibling_map, cpu_default_map);
    + if (i != first_cpu(this_sibling_map))
                             continue;
     
    - init_sched_build_groups(sched_group_cpus, cpu_sibling_map[i],
    + init_sched_build_groups(sched_group_cpus, this_sibling_mask,
                                                     &cpu_to_cpu_group);
             }
     #endif
     
    + /* Set up isolated groups */
    + for_each_cpu_mask(i, cpu_isolated_map) {
    + cpumask_t mask;
    + cpus_clear(mask);
    + cpu_set(i, mask);
    + init_sched_build_groups(sched_group_isolated, mask,
    + &cpu_to_isolated_group);
    + }
    +
             /* Set up physical groups */
             for (i = 0; i < MAX_NUMNODES; i++) {
                     cpumask_t nodemask = node_to_cpumask(i);
     
    - cpus_and(nodemask, nodemask, cpu_possible_map);
    + cpus_and(nodemask, nodemask, cpu_default_map);
                     if (cpus_empty(nodemask))
                             continue;
     
    @@ -3824,12 +3892,12 @@ __init static void arch_init_sched_domai
     
     #ifdef CONFIG_NUMA
             /* Set up node groups */
    - init_sched_build_groups(sched_group_nodes, cpu_possible_map,
    + init_sched_build_groups(sched_group_nodes, cpu_default_map,
                                             &cpu_to_node_group);
     #endif
     
             /* Calculate CPU power for physical packages and nodes */
    - for_each_cpu(i) {
    + for_each_cpu_mask(i, cpu_default_map) {
                     int power;
                     struct sched_domain *sd;
     #ifdef CONFIG_SCHED_SMT
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

  • Next message: Andi Kleen: "Re: [PATCH] Improve pci_alloc_consistent wrapper on preemptive kernels"

    Relevant Pages