From: Lai Jiangshan <la...@linux.alibaba.com> wq_online_cpumask is the cached result of cpu_online_mask with the going-down cpu cleared. It is needed for later patches for setting correct cpumask for workers and break affinity initiatively.
The first usage of wq_online_cpumask is also in this patch. wq_calc_node_cpumask() and wq_update_unbound_numa() can be simplified a little. Acked-by: Tejun Heo <t...@kernel.org> Signed-off-by: Lai Jiangshan <la...@linux.alibaba.com> --- kernel/workqueue.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 5f3c86eaed7a..84842f10e6a2 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -310,6 +310,9 @@ static bool workqueue_freezing; /* PL: have wqs started freezing? */ /* PL: allowable cpus for unbound wqs and work items */ static cpumask_var_t wq_unbound_cpumask; +/* PL: online cpus (cpu_online_mask with the going-down cpu cleared) */ +static cpumask_var_t wq_online_cpumask; + /* CPU where unbound work was last round robin scheduled from this CPU */ static DEFINE_PER_CPU(int, wq_rr_cpu_last); @@ -3833,12 +3836,10 @@ static struct pool_workqueue *alloc_unbound_pwq(struct workqueue_struct *wq, * wq_calc_node_cpumask - calculate a wq_attrs' cpumask for the specified node * @attrs: the wq_attrs of the default pwq of the target workqueue * @node: the target NUMA node - * @cpu_going_down: if >= 0, the CPU to consider as offline * @cpumask: outarg, the resulting cpumask * - * Calculate the cpumask a workqueue with @attrs should use on @node. If - * @cpu_going_down is >= 0, that cpu is considered offline during - * calculation. The result is stored in @cpumask. + * Calculate the cpumask a workqueue with @attrs should use on @node. + * The result is stored in @cpumask. * * If NUMA affinity is not enabled, @attrs->cpumask is always used. If * enabled and @node has online CPUs requested by @attrs, the returned @@ -3852,15 +3853,14 @@ static struct pool_workqueue *alloc_unbound_pwq(struct workqueue_struct *wq, * %false if equal. */ static bool wq_calc_node_cpumask(const struct workqueue_attrs *attrs, int node, - int cpu_going_down, cpumask_t *cpumask) + cpumask_t *cpumask) { if (!wq_numa_enabled || attrs->no_numa) goto use_dfl; /* does @node have any online CPUs @attrs wants? */ cpumask_and(cpumask, cpumask_of_node(node), attrs->cpumask); - if (cpu_going_down >= 0) - cpumask_clear_cpu(cpu_going_down, cpumask); + cpumask_and(cpumask, cpumask, wq_online_cpumask); if (cpumask_empty(cpumask)) goto use_dfl; @@ -3969,7 +3969,7 @@ apply_wqattrs_prepare(struct workqueue_struct *wq, goto out_free; for_each_node(node) { - if (wq_calc_node_cpumask(new_attrs, node, -1, tmp_attrs->cpumask)) { + if (wq_calc_node_cpumask(new_attrs, node, tmp_attrs->cpumask)) { ctx->pwq_tbl[node] = alloc_unbound_pwq(wq, tmp_attrs); if (!ctx->pwq_tbl[node]) goto out_free; @@ -4094,7 +4094,6 @@ int apply_workqueue_attrs(struct workqueue_struct *wq, * wq_update_unbound_numa - update NUMA affinity of a wq for CPU hot[un]plug * @wq: the target workqueue * @cpu: the CPU coming up or going down - * @online: whether @cpu is coming up or going down * * This function is to be called from %CPU_DOWN_PREPARE, %CPU_ONLINE and * %CPU_DOWN_FAILED. @cpu is being hot[un]plugged, update NUMA affinity of @@ -4112,11 +4111,9 @@ int apply_workqueue_attrs(struct workqueue_struct *wq, * affinity, it's the user's responsibility to flush the work item from * CPU_DOWN_PREPARE. */ -static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu, - bool online) +static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu) { int node = cpu_to_node(cpu); - int cpu_off = online ? -1 : cpu; struct pool_workqueue *old_pwq = NULL, *pwq; struct workqueue_attrs *target_attrs; cpumask_t *cpumask; @@ -4144,7 +4141,7 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu, * and create a new one if they don't match. If the target cpumask * equals the default pwq's, the default pwq should be used. */ - if (wq_calc_node_cpumask(wq->dfl_pwq->pool->attrs, node, cpu_off, cpumask)) { + if (wq_calc_node_cpumask(wq->dfl_pwq->pool->attrs, node, cpumask)) { if (cpumask_equal(cpumask, pwq->pool->attrs->cpumask)) return; } else { @@ -5081,6 +5078,7 @@ int workqueue_online_cpu(unsigned int cpu) int pi; mutex_lock(&wq_pool_mutex); + cpumask_set_cpu(cpu, wq_online_cpumask); for_each_pool(pool, pi) { mutex_lock(&wq_pool_attach_mutex); @@ -5095,7 +5093,7 @@ int workqueue_online_cpu(unsigned int cpu) /* update NUMA affinity of unbound workqueues */ list_for_each_entry(wq, &workqueues, list) - wq_update_unbound_numa(wq, cpu, true); + wq_update_unbound_numa(wq, cpu); mutex_unlock(&wq_pool_mutex); return 0; @@ -5113,8 +5111,9 @@ int workqueue_offline_cpu(unsigned int cpu) /* update NUMA affinity of unbound workqueues */ mutex_lock(&wq_pool_mutex); + cpumask_clear_cpu(cpu, wq_online_cpumask); list_for_each_entry(wq, &workqueues, list) - wq_update_unbound_numa(wq, cpu, false); + wq_update_unbound_numa(wq, cpu); mutex_unlock(&wq_pool_mutex); return 0; @@ -5951,6 +5950,9 @@ void __init workqueue_init_early(void) BUILD_BUG_ON(__alignof__(struct pool_workqueue) < __alignof__(long long)); + BUG_ON(!alloc_cpumask_var(&wq_online_cpumask, GFP_KERNEL)); + cpumask_copy(wq_online_cpumask, cpu_online_mask); + BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL)); cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(hk_flags)); @@ -6047,7 +6049,7 @@ void __init workqueue_init(void) } list_for_each_entry(wq, &workqueues, list) { - wq_update_unbound_numa(wq, smp_processor_id(), true); + wq_update_unbound_numa(wq, smp_processor_id()); WARN(init_rescuer(wq), "workqueue: failed to create early rescuer for %s", wq->name); -- 2.19.1.6.gb485710b