Revert "bdi: add a user-tunable cpu_list for the bdi flusher threads"

[platform/adaptation/renesas_rcar/renesas_kernel.git] / mm / backing-dev.c

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index bd6a6ca..d3ca2b3 100644 (file)
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -10,7 +10,6 @@
 #include <linux/module.h>
 #include <linux/writeback.h>
 #include <linux/device.h>
-#include <linux/slab.h>
 #include <trace/events/writeback.h>
 
 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
@@ -222,63 +221,12 @@ static ssize_t max_ratio_store(struct device *dev,
 }
 BDI_SHOW(max_ratio, bdi->max_ratio)
 
-static ssize_t cpu_list_store(struct device *dev,
-               struct device_attribute *attr, const char *buf, size_t count)
-{
-       struct backing_dev_info *bdi = dev_get_drvdata(dev);
-       struct bdi_writeback *wb = &bdi->wb;
-       cpumask_var_t newmask;
-       ssize_t ret;
-       struct task_struct *task;
-
-       if (!alloc_cpumask_var(&newmask, GFP_KERNEL))
-               return -ENOMEM;
-
-       ret = cpulist_parse(buf, newmask);
-       if (!ret) {
-               spin_lock_bh(&bdi->wb_lock);
-               task = wb->task;
-               if (task)
-                       get_task_struct(task);
-               spin_unlock_bh(&bdi->wb_lock);
-
-               mutex_lock(&bdi->flusher_cpumask_lock);
-               if (task) {
-                       ret = set_cpus_allowed_ptr(task, newmask);
-                       put_task_struct(task);
-               }
-               if (ret == 0) {
-                       cpumask_copy(bdi->flusher_cpumask, newmask);
-                       ret = count;
-               }
-               mutex_unlock(&bdi->flusher_cpumask_lock);
-
-       }
-       free_cpumask_var(newmask);
-
-       return ret;
-}
-
-static ssize_t cpu_list_show(struct device *dev,
-               struct device_attribute *attr, char *page)
-{
-       struct backing_dev_info *bdi = dev_get_drvdata(dev);
-       ssize_t ret;
-
-       mutex_lock(&bdi->flusher_cpumask_lock);
-       ret = cpulist_scnprintf(page, PAGE_SIZE-1, bdi->flusher_cpumask);
-       mutex_unlock(&bdi->flusher_cpumask_lock);
-
-       return ret;
-}
-
 #define __ATTR_RW(attr) __ATTR(attr, 0644, attr##_show, attr##_store)
 
 static struct device_attribute bdi_dev_attrs[] = {
        __ATTR_RW(read_ahead_kb),
        __ATTR_RW(min_ratio),
        __ATTR_RW(max_ratio),
-       __ATTR_RW(cpu_list),
        __ATTR_NULL,
 };
 
@@ -480,7 +428,6 @@ static int bdi_forker_thread(void *ptr)
                                writeback_inodes_wb(&bdi->wb, 1024,
                                                    WB_REASON_FORKER_THREAD);
                        } else {
-                               int ret;
                                /*
                                 * The spinlock makes sure we do not lose
                                 * wake-ups when racing with 'bdi_queue_work()'.
@@ -490,14 +437,6 @@ static int bdi_forker_thread(void *ptr)
                                spin_lock_bh(&bdi->wb_lock);
                                bdi->wb.task = task;
                                spin_unlock_bh(&bdi->wb_lock);
-                               mutex_lock(&bdi->flusher_cpumask_lock);
-                               ret = set_cpus_allowed_ptr(task,
-                                                       bdi->flusher_cpumask);
-                               mutex_unlock(&bdi->flusher_cpumask_lock);
-                               if (ret)
-                                       printk_once("%s: failed to bind flusher"
-                                                   " thread %s, error %d\n",
-                                                   __func__, task->comm, ret);
                                wake_up_process(task);
                        }
                        bdi_clear_pending(bdi);
@@ -570,17 +509,6 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
                                                dev_name(dev));
                if (IS_ERR(wb->task))
                        return PTR_ERR(wb->task);
-       } else {
-               int node;
-               /*
-                * Set up a default cpumask for the flusher threads that
-                * includes all cpus on the same numa node as the device.
-                * The mask may be overridden via sysfs.
-                */
-               node = dev_to_node(bdi->dev);
-               if (node != NUMA_NO_NODE)
-                       cpumask_copy(bdi->flusher_cpumask,
-                                    cpumask_of_node(node));
        }
 
        bdi_debug_register(bdi, dev_name(dev));
@@ -706,15 +634,6 @@ int bdi_init(struct backing_dev_info *bdi)
 
        bdi_wb_init(&bdi->wb, bdi);
 
-       if (!bdi_cap_flush_forker(bdi)) {
-               bdi->flusher_cpumask = kmalloc(sizeof(cpumask_t), GFP_KERNEL);
-               if (!bdi->flusher_cpumask)
-                       return -ENOMEM;
-               cpumask_setall(bdi->flusher_cpumask);
-               mutex_init(&bdi->flusher_cpumask_lock);
-       } else
-               bdi->flusher_cpumask = NULL;
-
        for (i = 0; i < NR_BDI_STAT_ITEMS; i++) {
                err = percpu_counter_init(&bdi->bdi_stat[i], 0);
                if (err)
@@ -737,7 +656,6 @@ int bdi_init(struct backing_dev_info *bdi)
 err:
                while (i--)
                        percpu_counter_destroy(&bdi->bdi_stat[i]);
-               kfree(bdi->flusher_cpumask);
        }
 
        return err;
@@ -765,8 +683,6 @@ void bdi_destroy(struct backing_dev_info *bdi)
 
        bdi_unregister(bdi);
 
-       kfree(bdi->flusher_cpumask);
-
        /*
         * If bdi_unregister() had already been called earlier, the
         * wakeup_timer could still be armed because bdi_prune_sb()