diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cgroup.c | 19 | ||||
| -rw-r--r-- | kernel/cpuset.c | 43 | ||||
| -rw-r--r-- | kernel/exit.c | 2 | ||||
| -rw-r--r-- | kernel/fork.c | 22 |
4 files changed, 37 insertions, 49 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 1ece8e20fdb..f4ea4b6f3cf 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4881,9 +4881,9 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css) rcu_assign_pointer(id->css, NULL); rcu_assign_pointer(css->id, NULL); - write_lock(&ss->id_lock); + spin_lock(&ss->id_lock); idr_remove(&ss->idr, id->id); - write_unlock(&ss->id_lock); + spin_unlock(&ss->id_lock); kfree_rcu(id, rcu_head); } EXPORT_SYMBOL_GPL(free_css_id); @@ -4909,10 +4909,10 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth) error = -ENOMEM; goto err_out; } - write_lock(&ss->id_lock); + spin_lock(&ss->id_lock); /* Don't use 0. allocates an ID of 1-65535 */ error = idr_get_new_above(&ss->idr, newid, 1, &myid); - write_unlock(&ss->id_lock); + spin_unlock(&ss->id_lock); /* Returns error when there are no free spaces for new ID.*/ if (error) { @@ -4927,9 +4927,9 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth) return newid; remove_idr: error = -ENOSPC; - write_lock(&ss->id_lock); + spin_lock(&ss->id_lock); idr_remove(&ss->idr, myid); - write_unlock(&ss->id_lock); + spin_unlock(&ss->id_lock); err_out: kfree(newid); return ERR_PTR(error); @@ -4941,7 +4941,7 @@ static int __init_or_module cgroup_init_idr(struct cgroup_subsys *ss, { struct css_id *newid; - rwlock_init(&ss->id_lock); + spin_lock_init(&ss->id_lock); idr_init(&ss->idr); newid = get_new_cssid(ss, 0); @@ -5029,6 +5029,8 @@ css_get_next(struct cgroup_subsys *ss, int id, return NULL; BUG_ON(!ss->use_id); + WARN_ON_ONCE(!rcu_read_lock_held()); + /* fill start point for scan */ tmpid = id; while (1) { @@ -5036,10 +5038,7 @@ css_get_next(struct cgroup_subsys *ss, int id, * scan next entry from bitmap(tree), tmpid is updated after * idr_get_next(). */ - read_lock(&ss->id_lock); tmp = idr_get_next(&ss->idr, &tmpid); - read_unlock(&ss->id_lock); - if (!tmp) break; if (tmp->depth >= depth && tmp->stack[depth] == rootid) { diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 5d575836dba..1010cc61931 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -964,7 +964,6 @@ static void cpuset_change_task_nodemask(struct task_struct *tsk, { bool need_loop; -repeat: /* * Allow tasks that have access to memory reserves because they have * been OOM killed to get memory anywhere. @@ -983,45 +982,19 @@ repeat: */ need_loop = task_has_mempolicy(tsk) || !nodes_intersects(*newmems, tsk->mems_allowed); - nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems); - mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1); - /* - * ensure checking ->mems_allowed_change_disable after setting all new - * allowed nodes. - * - * the read-side task can see an nodemask with new allowed nodes and - * old allowed nodes. and if it allocates page when cpuset clears newly - * disallowed ones continuous, it can see the new allowed bits. - * - * And if setting all new allowed nodes is after the checking, setting - * all new allowed nodes and clearing newly disallowed ones will be done - * continuous, and the read-side task may find no node to alloc page. - */ - smp_mb(); + if (need_loop) + write_seqcount_begin(&tsk->mems_allowed_seq); - /* - * Allocation of memory is very fast, we needn't sleep when waiting - * for the read-side. - */ - while (need_loop && ACCESS_ONCE(tsk->mems_allowed_change_disable)) { - task_unlock(tsk); - if (!task_curr(tsk)) - yield(); - goto repeat; - } - - /* - * ensure checking ->mems_allowed_change_disable before clearing all new - * disallowed nodes. - * - * if clearing newly disallowed bits before the checking, the read-side - * task may find no node to alloc page. - */ - smp_mb(); + nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems); + mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1); mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP2); tsk->mems_allowed = *newmems; + + if (need_loop) + write_seqcount_end(&tsk->mems_allowed_seq); + task_unlock(tsk); } diff --git a/kernel/exit.c b/kernel/exit.c index 7ad335c3045..16b07bfac22 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -935,7 +935,7 @@ void do_exit(long code) acct_update_integrals(tsk); /* sync mm's RSS info before statistics gathering */ if (tsk->mm) - sync_mm_rss(tsk, tsk->mm); + sync_mm_rss(tsk->mm); group_dead = atomic_dec_and_test(&tsk->signal->live); if (group_dead) { hrtimer_cancel(&tsk->signal->real_timer); diff --git a/kernel/fork.c b/kernel/fork.c index 26a7138bb84..37674ec55cd 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -512,6 +512,23 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p) return NULL; } +static void check_mm(struct mm_struct *mm) +{ + int i; + + for (i = 0; i < NR_MM_COUNTERS; i++) { + long x = atomic_long_read(&mm->rss_stat.count[i]); + + if (unlikely(x)) + printk(KERN_ALERT "BUG: Bad rss-counter state " + "mm:%p idx:%d val:%ld\n", mm, i, x); + } + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + VM_BUG_ON(mm->pmd_huge_pte); +#endif +} + /* * Allocate and initialize an mm_struct. */ @@ -539,9 +556,7 @@ void __mmdrop(struct mm_struct *mm) mm_free_pgd(mm); destroy_context(mm); mmu_notifier_mm_destroy(mm); -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - VM_BUG_ON(mm->pmd_huge_pte); -#endif + check_mm(mm); free_mm(mm); } EXPORT_SYMBOL_GPL(__mmdrop); @@ -1223,6 +1238,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, #ifdef CONFIG_CPUSETS p->cpuset_mem_spread_rotor = NUMA_NO_NODE; p->cpuset_slab_spread_rotor = NUMA_NO_NODE; + seqcount_init(&p->mems_allowed_seq); #endif #ifdef CONFIG_TRACE_IRQFLAGS p->irq_events = 0; |