From: Hidetoshi Seto Date: Tue, 15 Apr 2008 05:04:23 +0000 (+0900) Subject: sched, cpuset: customize sched domains, core X-Git-Tag: v2.6.26-rc1~1132^2~12 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1d3504fcf5606579d60b649d19f44b3871c1ddae;p=linux-2.6 sched, cpuset: customize sched domains, core [rebased for sched-devel/latest] - Add a new cpuset file, having levels: sched_relax_domain_level - Modify partition_sched_domains() and build_sched_domains() to take attributes parameter passed from cpuset. - Fill newidle_idx for node domains which currently unused but might be required if sched_relax_domain_level become higher. - We can change the default level by boot option 'relax_domain_level='. Signed-off-by: Hidetoshi Seto Signed-off-by: Ingo Molnar --- diff --git a/include/asm-ia64/topology.h b/include/asm-ia64/topology.h index f929dde853..f2f72ef2a8 100644 --- a/include/asm-ia64/topology.h +++ b/include/asm-ia64/topology.h @@ -93,7 +93,7 @@ void build_cpu_to_node_map(void); .cache_nice_tries = 2, \ .busy_idx = 3, \ .idle_idx = 2, \ - .newidle_idx = 0, /* unused */ \ + .newidle_idx = 2, \ .wake_idx = 1, \ .forkexec_idx = 1, \ .flags = SD_LOAD_BALANCE \ diff --git a/include/asm-sh/topology.h b/include/asm-sh/topology.h index f402a3b1cf..34cdb28e8f 100644 --- a/include/asm-sh/topology.h +++ b/include/asm-sh/topology.h @@ -16,7 +16,7 @@ .cache_nice_tries = 2, \ .busy_idx = 3, \ .idle_idx = 2, \ - .newidle_idx = 0, \ + .newidle_idx = 2, \ .wake_idx = 1, \ .forkexec_idx = 1, \ .flags = SD_LOAD_BALANCE \ diff --git a/include/asm-x86/topology.h b/include/asm-x86/topology.h index 9ef74c5d5a..22073268b4 100644 --- a/include/asm-x86/topology.h +++ b/include/asm-x86/topology.h @@ -147,7 +147,7 @@ extern unsigned long node_remap_size[]; # define SD_CACHE_NICE_TRIES 2 # define SD_IDLE_IDX 2 -# define SD_NEWIDLE_IDX 0 +# define SD_NEWIDLE_IDX 2 # define SD_FORKEXEC_IDX 1 #endif diff --git a/include/linux/sched.h b/include/linux/sched.h index ada24022d2..11f47249cd 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -704,6 +704,7 @@ enum cpu_idle_type { #define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */ #define SD_SHARE_PKG_RESOURCES 512 /* Domain members share cpu pkg resources */ #define SD_SERIALIZE 1024 /* Only a single load balancing instance */ +#define SD_WAKE_IDLE_FAR 2048 /* Gain latency sacrificing cache hit */ #define BALANCE_FOR_MC_POWER \ (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0) @@ -733,6 +734,24 @@ struct sched_group { u32 reciprocal_cpu_power; }; +enum sched_domain_level { + SD_LV_NONE = 0, + SD_LV_SIBLING, + SD_LV_MC, + SD_LV_CPU, + SD_LV_NODE, + SD_LV_ALLNODES, + SD_LV_MAX +}; + +struct sched_domain_attr { + int relax_domain_level; +}; + +#define SD_ATTR_INIT (struct sched_domain_attr) { \ + .relax_domain_level = -1, \ +} + struct sched_domain { /* These fields must be setup */ struct sched_domain *parent; /* top domain must be null terminated */ @@ -750,6 +769,7 @@ struct sched_domain { unsigned int wake_idx; unsigned int forkexec_idx; int flags; /* See SD_* */ + enum sched_domain_level level; /* Runtime fields. */ unsigned long last_balance; /* init to jiffies. units in jiffies */ @@ -789,7 +809,8 @@ struct sched_domain { #endif }; -extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new); +extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new, + struct sched_domain_attr *dattr_new); extern int arch_reinit_sched_domains(void); #endif /* CONFIG_SMP */ diff --git a/kernel/cpuset.c b/kernel/cpuset.c index b0c870b2ac..8b35fbd829 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -98,6 +98,9 @@ struct cpuset { /* partition number for rebuild_sched_domains() */ int pn; + /* for custom sched domain */ + int relax_domain_level; + /* used for walking a cpuset heirarchy */ struct list_head stack_list; }; @@ -478,6 +481,16 @@ static int cpusets_overlap(struct cpuset *a, struct cpuset *b) return cpus_intersects(a->cpus_allowed, b->cpus_allowed); } +static void +update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c) +{ + if (!dattr) + return; + if (dattr->relax_domain_level < c->relax_domain_level) + dattr->relax_domain_level = c->relax_domain_level; + return; +} + /* * rebuild_sched_domains() * @@ -553,12 +566,14 @@ static void rebuild_sched_domains(void) int csn; /* how many cpuset ptrs in csa so far */ int i, j, k; /* indices for partition finding loops */ cpumask_t *doms; /* resulting partition; i.e. sched domains */ + struct sched_domain_attr *dattr; /* attributes for custom domains */ int ndoms; /* number of sched domains in result */ int nslot; /* next empty doms[] cpumask_t slot */ q = NULL; csa = NULL; doms = NULL; + dattr = NULL; /* Special case for the 99% of systems with one, full, sched domain */ if (is_sched_load_balance(&top_cpuset)) { @@ -566,6 +581,11 @@ static void rebuild_sched_domains(void) doms = kmalloc(sizeof(cpumask_t), GFP_KERNEL); if (!doms) goto rebuild; + dattr = kmalloc(sizeof(struct sched_domain_attr), GFP_KERNEL); + if (dattr) { + *dattr = SD_ATTR_INIT; + update_domain_attr(dattr, &top_cpuset); + } *doms = top_cpuset.cpus_allowed; goto rebuild; } @@ -622,6 +642,7 @@ restart: doms = kmalloc(ndoms * sizeof(cpumask_t), GFP_KERNEL); if (!doms) goto rebuild; + dattr = kmalloc(ndoms * sizeof(struct sched_domain_attr), GFP_KERNEL); for (nslot = 0, i = 0; i < csn; i++) { struct cpuset *a = csa[i]; @@ -644,12 +665,15 @@ restart: } cpus_clear(*dp); + if (dattr) + *(dattr + nslot) = SD_ATTR_INIT; for (j = i; j < csn; j++) { struct cpuset *b = csa[j]; if (apn == b->pn) { cpus_or(*dp, *dp, b->cpus_allowed); b->pn = -1; + update_domain_attr(dattr, b); } } nslot++; @@ -660,7 +684,7 @@ restart: rebuild: /* Have scheduler rebuild sched domains */ get_online_cpus(); - partition_sched_domains(ndoms, doms); + partition_sched_domains(ndoms, doms, dattr); put_online_cpus(); done: @@ -668,6 +692,7 @@ done: kfifo_free(q); kfree(csa); /* Don't kfree(doms) -- partition_sched_domains() does that. */ + /* Don't kfree(dattr) -- partition_sched_domains() does that. */ } static inline int started_after_time(struct task_struct *t1, @@ -1011,6 +1036,21 @@ static int update_memory_pressure_enabled(struct cpuset *cs, char *buf) return 0; } +static int update_relax_domain_level(struct cpuset *cs, char *buf) +{ + int val = simple_strtol(buf, NULL, 10); + + if (val < 0) + val = -1; + + if (val != cs->relax_domain_level) { + cs->relax_domain_level = val; + rebuild_sched_domains(); + } + + return 0; +} + /* * update_flag - read a 0 or a 1 in a file and update associated flag * bit: the bit to update (CS_CPU_EXCLUSIVE, CS_MEM_EXCLUSIVE, @@ -1202,6 +1242,7 @@ typedef enum { FILE_CPU_EXCLUSIVE, FILE_MEM_EXCLUSIVE, FILE_SCHED_LOAD_BALANCE, + FILE_SCHED_RELAX_DOMAIN_LEVEL, FILE_MEMORY_PRESSURE_ENABLED, FILE_MEMORY_PRESSURE, FILE_SPREAD_PAGE, @@ -1256,6 +1297,9 @@ static ssize_t cpuset_common_file_write(struct cgroup *cont, case FILE_SCHED_LOAD_BALANCE: retval = update_flag(CS_SCHED_LOAD_BALANCE, cs, buffer); break; + case FILE_SCHED_RELAX_DOMAIN_LEVEL: + retval = update_relax_domain_level(cs, buffer); + break; case FILE_MEMORY_MIGRATE: retval = update_flag(CS_MEMORY_MIGRATE, cs, buffer); break; @@ -1354,6 +1398,9 @@ static ssize_t cpuset_common_file_read(struct cgroup *cont, case FILE_SCHED_LOAD_BALANCE: *s++ = is_sched_load_balance(cs) ? '1' : '0'; break; + case FILE_SCHED_RELAX_DOMAIN_LEVEL: + s += sprintf(s, "%d", cs->relax_domain_level); + break; case FILE_MEMORY_MIGRATE: *s++ = is_memory_migrate(cs) ? '1' : '0'; break; @@ -1424,6 +1471,13 @@ static struct cftype cft_sched_load_balance = { .private = FILE_SCHED_LOAD_BALANCE, }; +static struct cftype cft_sched_relax_domain_level = { + .name = "sched_relax_domain_level", + .read = cpuset_common_file_read, + .write = cpuset_common_file_write, + .private = FILE_SCHED_RELAX_DOMAIN_LEVEL, +}; + static struct cftype cft_memory_migrate = { .name = "memory_migrate", .read = cpuset_common_file_read, @@ -1475,6 +1529,9 @@ static int cpuset_populate(struct cgroup_subsys *ss, struct cgroup *cont) return err; if ((err = cgroup_add_file(cont, ss, &cft_sched_load_balance)) < 0) return err; + if ((err = cgroup_add_file(cont, ss, + &cft_sched_relax_domain_level)) < 0) + return err; if ((err = cgroup_add_file(cont, ss, &cft_memory_pressure)) < 0) return err; if ((err = cgroup_add_file(cont, ss, &cft_spread_page)) < 0) @@ -1559,6 +1616,7 @@ static struct cgroup_subsys_state *cpuset_create( nodes_clear(cs->mems_allowed); cs->mems_generation = cpuset_mems_generation++; fmeter_init(&cs->fmeter); + cs->relax_domain_level = -1; cs->parent = parent; number_of_cpusets++; @@ -1631,6 +1689,7 @@ int __init cpuset_init(void) fmeter_init(&top_cpuset.fmeter); top_cpuset.mems_generation = cpuset_mems_generation++; set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags); + top_cpuset.relax_domain_level = -1; err = register_filesystem(&cpuset_fs_type); if (err < 0) diff --git a/kernel/sched.c b/kernel/sched.c index 475e3fcab7..62d7481cac 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6771,6 +6771,7 @@ static noinline void sd_init_##type(struct sched_domain *sd) \ { \ memset(sd, 0, sizeof(*sd)); \ *sd = SD_##type##_INIT; \ + sd->level = SD_LV_##type; \ } SD_INIT_FUNC(CPU) @@ -6819,11 +6820,42 @@ struct allmasks { #define SCHED_CPUMASK_VAR(v, a) cpumask_t *v = (cpumask_t *) \ ((unsigned long)(a) + offsetof(struct allmasks, v)) +static int default_relax_domain_level = -1; + +static int __init setup_relax_domain_level(char *str) +{ + default_relax_domain_level = simple_strtoul(str, NULL, 0); + return 1; +} +__setup("relax_domain_level=", setup_relax_domain_level); + +static void set_domain_attribute(struct sched_domain *sd, + struct sched_domain_attr *attr) +{ + int request; + + if (!attr || attr->relax_domain_level < 0) { + if (default_relax_domain_level < 0) + return; + else + request = default_relax_domain_level; + } else + request = attr->relax_domain_level; + if (request < sd->level) { + /* turn off idle balance on this domain */ + sd->flags &= ~(SD_WAKE_IDLE|SD_BALANCE_NEWIDLE); + } else { + /* turn on idle balance on this domain */ + sd->flags |= (SD_WAKE_IDLE_FAR|SD_BALANCE_NEWIDLE); + } +} + /* * Build sched domains for a given set of cpus and attach the sched domains * to the individual cpus */ -static int build_sched_domains(const cpumask_t *cpu_map) +static int __build_sched_domains(const cpumask_t *cpu_map, + struct sched_domain_attr *attr) { int i; struct root_domain *rd; @@ -6887,6 +6919,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) SD_NODES_PER_DOMAIN*cpus_weight(*nodemask)) { sd = &per_cpu(allnodes_domains, i); SD_INIT(sd, ALLNODES); + set_domain_attribute(sd, attr); sd->span = *cpu_map; cpu_to_allnodes_group(i, cpu_map, &sd->groups, tmpmask); p = sd; @@ -6896,6 +6929,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) sd = &per_cpu(node_domains, i); SD_INIT(sd, NODE); + set_domain_attribute(sd, attr); sched_domain_node_span(cpu_to_node(i), &sd->span); sd->parent = p; if (p) @@ -6906,6 +6940,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) p = sd; sd = &per_cpu(phys_domains, i); SD_INIT(sd, CPU); + set_domain_attribute(sd, attr); sd->span = *nodemask; sd->parent = p; if (p) @@ -6916,6 +6951,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) p = sd; sd = &per_cpu(core_domains, i); SD_INIT(sd, MC); + set_domain_attribute(sd, attr); sd->span = cpu_coregroup_map(i); cpus_and(sd->span, sd->span, *cpu_map); sd->parent = p; @@ -6927,6 +6963,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) p = sd; sd = &per_cpu(cpu_domains, i); SD_INIT(sd, SIBLING); + set_domain_attribute(sd, attr); sd->span = per_cpu(cpu_sibling_map, i); cpus_and(sd->span, sd->span, *cpu_map); sd->parent = p; @@ -7124,8 +7161,15 @@ error: #endif } +static int build_sched_domains(const cpumask_t *cpu_map) +{ + return __build_sched_domains(cpu_map, NULL); +} + static cpumask_t *doms_cur; /* current sched domains */ static int ndoms_cur; /* number of sched domains in 'doms_cur' */ +static struct sched_domain_attr *dattr_cur; /* attribues of custom domains + in 'doms_cur' */ /* * Special case: If a kmalloc of a doms_cur partition (array of @@ -7153,6 +7197,7 @@ static int arch_init_sched_domains(const cpumask_t *cpu_map) if (!doms_cur) doms_cur = &fallback_doms; cpus_andnot(*doms_cur, *cpu_map, cpu_isolated_map); + dattr_cur = NULL; err = build_sched_domains(doms_cur); register_sched_domain_sysctl(); @@ -7182,6 +7227,22 @@ static void detach_destroy_domains(const cpumask_t *cpu_map) arch_destroy_sched_domains(cpu_map, &tmpmask); } +/* handle null as "default" */ +static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur, + struct sched_domain_attr *new, int idx_new) +{ + struct sched_domain_attr tmp; + + /* fast path */ + if (!new && !cur) + return 1; + + tmp = SD_ATTR_INIT; + return !memcmp(cur ? (cur + idx_cur) : &tmp, + new ? (new + idx_new) : &tmp, + sizeof(struct sched_domain_attr)); +} + /* * Partition sched domains as specified by the 'ndoms_new' * cpumasks in the array doms_new[] of cpumasks. This compares @@ -7203,7 +7264,8 @@ static void detach_destroy_domains(const cpumask_t *cpu_map) * * Call with hotplug lock held */ -void partition_sched_domains(int ndoms_new, cpumask_t *doms_new) +void partition_sched_domains(int ndoms_new, cpumask_t *doms_new, + struct sched_domain_attr *dattr_new) { int i, j; @@ -7216,12 +7278,14 @@ void partition_sched_domains(int ndoms_new, cpumask_t *doms_new) ndoms_new = 1; doms_new = &fallback_doms; cpus_andnot(doms_new[0], cpu_online_map, cpu_isolated_map); + dattr_new = NULL; } /* Destroy deleted domains */ for (i = 0; i < ndoms_cur; i++) { for (j = 0; j < ndoms_new; j++) { - if (cpus_equal(doms_cur[i], doms_new[j])) + if (cpus_equal(doms_cur[i], doms_new[j]) + && dattrs_equal(dattr_cur, i, dattr_new, j)) goto match1; } /* no match - a current sched domain not in new doms_new[] */ @@ -7233,11 +7297,13 @@ match1: /* Build new domains */ for (i = 0; i < ndoms_new; i++) { for (j = 0; j < ndoms_cur; j++) { - if (cpus_equal(doms_new[i], doms_cur[j])) + if (cpus_equal(doms_new[i], doms_cur[j]) + && dattrs_equal(dattr_new, i, dattr_cur, j)) goto match2; } /* no match - add a new doms_new */ - build_sched_domains(doms_new + i); + __build_sched_domains(doms_new + i, + dattr_new ? dattr_new + i : NULL); match2: ; } @@ -7245,7 +7311,9 @@ match2: /* Remember the new sched domains */ if (doms_cur != &fallback_doms) kfree(doms_cur); + kfree(dattr_cur); /* kfree(NULL) is safe */ doms_cur = doms_new; + dattr_cur = dattr_new; ndoms_cur = ndoms_new; register_sched_domain_sysctl(); diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index de4250c53a..b43748efaa 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -940,7 +940,9 @@ static int wake_idle(int cpu, struct task_struct *p) return cpu; for_each_domain(cpu, sd) { - if (sd->flags & SD_WAKE_IDLE) { + if ((sd->flags & SD_WAKE_IDLE) + || ((sd->flags & SD_WAKE_IDLE_FAR) + && !task_hot(p, task_rq(p)->clock, sd))) { cpus_and(tmp, sd->span, p->cpus_allowed); for_each_cpu_mask(i, tmp) { if (idle_cpu(i)) {