From d01d4827858cdc2e1c437c87ab65ec0a00fd40f8 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 21 Sep 2009 11:06:27 +0200 Subject: sched: Always show Cpus_allowed field in /proc//status The Cpus_allowed fields in /proc//status is currently only shown in case of CONFIG_CPUSETS. However their contents are also useful for the !CONFIG_CPUSETS case. So change the current behaviour and always show these fields. Signed-off-by: Heiko Carstens Cc: Andrew Morton Cc: Oleg Nesterov Cc: Peter Zijlstra LKML-Reference: <20090921090627.GD4649@osiris.boeblingen.de.ibm.com> Signed-off-by: Ingo Molnar --- kernel/cpuset.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) (limited to 'kernel/cpuset.c') diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 7e75a41bd508..b81f7f096e1c 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -2499,15 +2499,9 @@ const struct file_operations proc_cpuset_operations = { }; #endif /* CONFIG_PROC_PID_CPUSET */ -/* Display task cpus_allowed, mems_allowed in /proc//status file. */ +/* Display task mems_allowed in /proc//status file. */ void cpuset_task_status_allowed(struct seq_file *m, struct task_struct *task) { - seq_printf(m, "Cpus_allowed:\t"); - seq_cpumask(m, &task->cpus_allowed); - seq_printf(m, "\n"); - seq_printf(m, "Cpus_allowed_list:\t"); - seq_cpumask_list(m, &task->cpus_allowed); - seq_printf(m, "\n"); seq_printf(m, "Mems_allowed:\t"); seq_nodemask(m, &task->mems_allowed); seq_printf(m, "\n"); -- cgit v1.2.2 From acc3f5d7cabbfd6cec71f0c1f9900621fa2d6ae7 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Tue, 3 Nov 2009 14:53:40 +1030 Subject: cpumask: Partition_sched_domains takes array of cpumask_var_t Currently partition_sched_domains() takes a 'struct cpumask *doms_new' which is a kmalloc'ed array of cpumask_t. You can't have such an array if 'struct cpumask' is undefined, as we plan for CONFIG_CPUMASK_OFFSTACK=y. So, we make this an array of cpumask_var_t instead: this is the same for the CONFIG_CPUMASK_OFFSTACK=n case, but requires multiple allocations for the CONFIG_CPUMASK_OFFSTACK=y case. Hence we add alloc_sched_domains() and free_sched_domains() functions. Signed-off-by: Rusty Russell Cc: Peter Zijlstra LKML-Reference: <200911031453.40668.rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar --- kernel/cpuset.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) (limited to 'kernel/cpuset.c') diff --git a/kernel/cpuset.c b/kernel/cpuset.c index d247381e7371..3cf2183b472d 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -537,8 +537,7 @@ update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c) * element of the partition (one sched domain) to be passed to * partition_sched_domains(). */ -/* FIXME: see the FIXME in partition_sched_domains() */ -static int generate_sched_domains(struct cpumask **domains, +static int generate_sched_domains(cpumask_var_t **domains, struct sched_domain_attr **attributes) { LIST_HEAD(q); /* queue of cpusets to be scanned */ @@ -546,7 +545,7 @@ static int generate_sched_domains(struct cpumask **domains, struct cpuset **csa; /* array of all cpuset ptrs */ int csn; /* how many cpuset ptrs in csa so far */ int i, j, k; /* indices for partition finding loops */ - struct cpumask *doms; /* resulting partition; i.e. sched domains */ + cpumask_var_t *doms; /* resulting partition; i.e. sched domains */ struct sched_domain_attr *dattr; /* attributes for custom domains */ int ndoms = 0; /* number of sched domains in result */ int nslot; /* next empty doms[] struct cpumask slot */ @@ -557,7 +556,8 @@ static int generate_sched_domains(struct cpumask **domains, /* Special case for the 99% of systems with one, full, sched domain */ if (is_sched_load_balance(&top_cpuset)) { - doms = kmalloc(cpumask_size(), GFP_KERNEL); + ndoms = 1; + doms = alloc_sched_domains(ndoms); if (!doms) goto done; @@ -566,9 +566,8 @@ static int generate_sched_domains(struct cpumask **domains, *dattr = SD_ATTR_INIT; update_domain_attr_tree(dattr, &top_cpuset); } - cpumask_copy(doms, top_cpuset.cpus_allowed); + cpumask_copy(doms[0], top_cpuset.cpus_allowed); - ndoms = 1; goto done; } @@ -636,7 +635,7 @@ restart: * Now we know how many domains to create. * Convert to and populate cpu masks. */ - doms = kmalloc(ndoms * cpumask_size(), GFP_KERNEL); + doms = alloc_sched_domains(ndoms); if (!doms) goto done; @@ -656,7 +655,7 @@ restart: continue; } - dp = doms + nslot; + dp = doms[nslot]; if (nslot == ndoms) { static int warnings = 10; @@ -718,7 +717,7 @@ done: static void do_rebuild_sched_domains(struct work_struct *unused) { struct sched_domain_attr *attr; - struct cpumask *doms; + cpumask_var_t *doms; int ndoms; get_online_cpus(); @@ -2052,7 +2051,7 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb, unsigned long phase, void *unused_cpu) { struct sched_domain_attr *attr; - struct cpumask *doms; + cpumask_var_t *doms; int ndoms; switch (phase) { -- cgit v1.2.2 From e1b8090bdf125f8b2e192149547fead7f302a89c Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Sun, 6 Dec 2009 20:41:16 +0100 Subject: cpumask: Fix generate_sched_domains() for UP Commit acc3f5d7cabbfd6cec71f0c1f9900621fa2d6ae7 ("cpumask: Partition_sched_domains takes array of cpumask_var_t") changed the function signature of generate_sched_domains() for the CONFIG_SMP=y case, but forgot to update the corresponding function for the CONFIG_SMP=n case, causing: kernel/cpuset.c:2073: warning: passing argument 1 of 'generate_sched_domains' from incompatible pointer type Signed-off-by: Geert Uytterhoeven Cc: Rusty Russell Cc: Linus Torvalds LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/cpuset.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/cpuset.c') diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 3cf2183b472d..43fb7e800028 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -737,7 +737,7 @@ static void do_rebuild_sched_domains(struct work_struct *unused) { } -static int generate_sched_domains(struct cpumask **domains, +static int generate_sched_domains(cpumask_var_t **domains, struct sched_domain_attr **attributes) { *domains = NULL; -- cgit v1.2.2 From 6ad4c18884e864cf4c77f9074d3d1816063f99cd Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 25 Nov 2009 13:31:39 +0100 Subject: sched: Fix balance vs hotplug race Since (e761b77: cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment) we have cpu_active_mask which is suppose to rule scheduler migration and load-balancing, except it never (fully) did. The particular problem being solved here is a crash in try_to_wake_up() where select_task_rq() ends up selecting an offline cpu because select_task_rq_fair() trusts the sched_domain tree to reflect the current state of affairs, similarly select_task_rq_rt() trusts the root_domain. However, the sched_domains are updated from CPU_DEAD, which is after the cpu is taken offline and after stop_machine is done. Therefore it can race perfectly well with code assuming the domains are right. Cure this by building the domains from cpu_active_mask on CPU_DOWN_PREPARE. Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/cpuset.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'kernel/cpuset.c') diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 43fb7e800028..ba401fab459f 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -872,7 +872,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, if (retval < 0) return retval; - if (!cpumask_subset(trialcs->cpus_allowed, cpu_online_mask)) + if (!cpumask_subset(trialcs->cpus_allowed, cpu_active_mask)) return -EINVAL; } retval = validate_change(cs, trialcs); @@ -2010,7 +2010,7 @@ static void scan_for_empty_cpusets(struct cpuset *root) } /* Continue past cpusets with all cpus, mems online */ - if (cpumask_subset(cp->cpus_allowed, cpu_online_mask) && + if (cpumask_subset(cp->cpus_allowed, cpu_active_mask) && nodes_subset(cp->mems_allowed, node_states[N_HIGH_MEMORY])) continue; @@ -2019,7 +2019,7 @@ static void scan_for_empty_cpusets(struct cpuset *root) /* Remove offline cpus and mems from this cpuset. */ mutex_lock(&callback_mutex); cpumask_and(cp->cpus_allowed, cp->cpus_allowed, - cpu_online_mask); + cpu_active_mask); nodes_and(cp->mems_allowed, cp->mems_allowed, node_states[N_HIGH_MEMORY]); mutex_unlock(&callback_mutex); @@ -2057,8 +2057,10 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb, switch (phase) { case CPU_ONLINE: case CPU_ONLINE_FROZEN: - case CPU_DEAD: - case CPU_DEAD_FROZEN: + case CPU_DOWN_PREPARE: + case CPU_DOWN_PREPARE_FROZEN: + case CPU_DOWN_FAILED: + case CPU_DOWN_FAILED_FROZEN: break; default: @@ -2067,7 +2069,7 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb, cgroup_lock(); mutex_lock(&callback_mutex); - cpumask_copy(top_cpuset.cpus_allowed, cpu_online_mask); + cpumask_copy(top_cpuset.cpus_allowed, cpu_active_mask); mutex_unlock(&callback_mutex); scan_for_empty_cpusets(&top_cpuset); ndoms = generate_sched_domains(&doms, &attr); @@ -2114,7 +2116,7 @@ static int cpuset_track_online_nodes(struct notifier_block *self, void __init cpuset_init_smp(void) { - cpumask_copy(top_cpuset.cpus_allowed, cpu_online_mask); + cpumask_copy(top_cpuset.cpus_allowed, cpu_active_mask); top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; hotcpu_notifier(cpuset_track_online_cpus, 0); -- cgit v1.2.2