diff options
| -rw-r--r-- | include/linux/workqueue.h | 2 | ||||
| -rw-r--r-- | kernel/workqueue.c | 91 |
2 files changed, 84 insertions, 9 deletions
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index 24b1e5070f4d..b0b9604b76b8 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -491,7 +491,7 @@ struct workqueue_attrs *alloc_workqueue_attrs(void); void free_workqueue_attrs(struct workqueue_attrs *attrs); int apply_workqueue_attrs(struct workqueue_struct *wq, const struct workqueue_attrs *attrs); -int workqueue_set_unbound_cpumask(cpumask_var_t cpumask); +extern int workqueue_unbound_exclude_cpumask(cpumask_var_t cpumask); extern bool queue_work_on(int cpu, struct workqueue_struct *wq, struct work_struct *work); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 6e578f576a6f..bd9d34eacd78 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -381,6 +381,12 @@ static bool workqueue_freezing; /* PL: have wqs started freezing? */ /* PL&A: allowable cpus for unbound wqs and work items */ static cpumask_var_t wq_unbound_cpumask; +/* PL: user requested unbound cpumask via sysfs */ +static cpumask_var_t wq_requested_unbound_cpumask; + +/* PL: isolated cpumask to be excluded from unbound cpumask */ +static cpumask_var_t wq_isolated_cpumask; + /* for further constrain wq_unbound_cpumask by cmdline parameter*/ static struct cpumask wq_cmdline_cpumask __initdata; @@ -5839,7 +5845,7 @@ static int workqueue_apply_unbound_cpumask(const cpumask_var_t unbound_cpumask) * -EINVAL - Invalid @cpumask * -ENOMEM - Failed to allocate memory for attrs or pwqs. */ -int workqueue_set_unbound_cpumask(cpumask_var_t cpumask) +static int workqueue_set_unbound_cpumask(cpumask_var_t cpumask) { int ret = -EINVAL; @@ -5850,6 +5856,7 @@ int workqueue_set_unbound_cpumask(cpumask_var_t cpumask) cpumask_and(cpumask, cpumask, cpu_possible_mask); if (!cpumask_empty(cpumask)) { apply_wqattrs_lock(); + cpumask_copy(wq_requested_unbound_cpumask, cpumask); if (cpumask_equal(cpumask, wq_unbound_cpumask)) { ret = 0; goto out_unlock; @@ -5864,6 +5871,44 @@ out_unlock: return ret; } +/** + * workqueue_unbound_exclude_cpumask - Exclude given CPUs from unbound cpumask + * @exclude_cpumask: the cpumask to be excluded from wq_unbound_cpumask + * + * This function can be called from cpuset code to provide a set of isolated + * CPUs that should be excluded from wq_unbound_cpumask. The caller must hold + * either cpus_read_lock or cpus_write_lock. + */ +int workqueue_unbound_exclude_cpumask(cpumask_var_t exclude_cpumask) +{ + cpumask_var_t cpumask; + int ret = 0; + + if (!zalloc_cpumask_var(&cpumask, GFP_KERNEL)) + return -ENOMEM; + + lockdep_assert_cpus_held(); + mutex_lock(&wq_pool_mutex); + + /* Save the current isolated cpumask & export it via sysfs */ + cpumask_copy(wq_isolated_cpumask, exclude_cpumask); + + /* + * If the operation fails, it will fall back to + * wq_requested_unbound_cpumask which is initially set to + * (HK_TYPE_WQ ∩ HK_TYPE_DOMAIN) house keeping mask and rewritten + * by any subsequent write to workqueue/cpumask sysfs file. + */ + if (!cpumask_andnot(cpumask, wq_requested_unbound_cpumask, exclude_cpumask)) + cpumask_copy(cpumask, wq_requested_unbound_cpumask); + if (!cpumask_equal(cpumask, wq_unbound_cpumask)) + ret = workqueue_apply_unbound_cpumask(cpumask); + + mutex_unlock(&wq_pool_mutex); + free_cpumask_var(cpumask); + return ret; +} + static int parse_affn_scope(const char *val) { int i; @@ -6158,19 +6203,36 @@ static struct bus_type wq_subsys = { .dev_groups = wq_sysfs_groups, }; -static ssize_t wq_unbound_cpumask_show(struct device *dev, - struct device_attribute *attr, char *buf) +static ssize_t __wq_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf, cpumask_var_t mask) { int written; mutex_lock(&wq_pool_mutex); - written = scnprintf(buf, PAGE_SIZE, "%*pb\n", - cpumask_pr_args(wq_unbound_cpumask)); + written = scnprintf(buf, PAGE_SIZE, "%*pb\n", cpumask_pr_args(mask)); mutex_unlock(&wq_pool_mutex); return written; } +static ssize_t wq_unbound_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return __wq_cpumask_show(dev, attr, buf, wq_unbound_cpumask); +} + +static ssize_t wq_requested_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return __wq_cpumask_show(dev, attr, buf, wq_requested_unbound_cpumask); +} + +static ssize_t wq_isolated_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return __wq_cpumask_show(dev, attr, buf, wq_isolated_cpumask); +} + static ssize_t wq_unbound_cpumask_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { @@ -6188,9 +6250,13 @@ static ssize_t wq_unbound_cpumask_store(struct device *dev, return ret ? ret : count; } -static struct device_attribute wq_sysfs_cpumask_attr = +static struct device_attribute wq_sysfs_cpumask_attrs[] = { __ATTR(cpumask, 0644, wq_unbound_cpumask_show, - wq_unbound_cpumask_store); + wq_unbound_cpumask_store), + __ATTR(cpumask_requested, 0444, wq_requested_cpumask_show, NULL), + __ATTR(cpumask_isolated, 0444, wq_isolated_cpumask_show, NULL), + __ATTR_NULL, +}; static int __init wq_sysfs_init(void) { @@ -6203,7 +6269,13 @@ static int __init wq_sysfs_init(void) dev_root = bus_get_dev_root(&wq_subsys); if (dev_root) { - err = device_create_file(dev_root, &wq_sysfs_cpumask_attr); + struct device_attribute *attr; + + for (attr = wq_sysfs_cpumask_attrs; attr->attr.name; attr++) { + err = device_create_file(dev_root, attr); + if (err) + break; + } put_device(dev_root); } return err; @@ -6534,11 +6606,14 @@ void __init workqueue_init_early(void) BUILD_BUG_ON(__alignof__(struct pool_workqueue) < __alignof__(long long)); BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL)); + BUG_ON(!alloc_cpumask_var(&wq_requested_unbound_cpumask, GFP_KERNEL)); + BUG_ON(!zalloc_cpumask_var(&wq_isolated_cpumask, GFP_KERNEL)); cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(HK_TYPE_WQ)); cpumask_and(wq_unbound_cpumask, wq_unbound_cpumask, housekeeping_cpumask(HK_TYPE_DOMAIN)); if (!cpumask_empty(&wq_cmdline_cpumask)) cpumask_and(wq_unbound_cpumask, wq_unbound_cpumask, &wq_cmdline_cpumask); + cpumask_copy(wq_requested_unbound_cpumask, wq_unbound_cpumask); pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC); |