From 01e14d6db9654be005a0a5384090aea2cde39976 Mon Sep 17 00:00:00 2001 From: David Fries Date: Wed, 15 Oct 2008 22:04:40 -0700 Subject: [PATCH] W1: don't delay search start Move the creation of the w1_process thread to after the device has been initialized. This way w1_process doesn't have to check to see if it has been initialized and the bus search can proceed without sleeping. That also eliminates two checks in the w1_process loop. The sleep now happens at the end of the loop not the beginning. Also added a comment for why the atomic_set was 2. Signed-off-by: David Fries Signed-off-by: Evgeniy Polyakov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/w1/w1.c | 19 ++++++------------- drivers/w1/w1_int.c | 26 +++++++++++++++++--------- 2 files changed, 23 insertions(+), 22 deletions(-) diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index aac03f151fe..730faa49d8d 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -813,21 +813,14 @@ int w1_process(void *data) struct w1_master *dev = (struct w1_master *) data; while (!kthread_should_stop() && !test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) { + if (dev->search_count) { + mutex_lock(&dev->mutex); + w1_search_process(dev, W1_SEARCH); + mutex_unlock(&dev->mutex); + } + try_to_freeze(); msleep_interruptible(w1_timeout * 1000); - - if (kthread_should_stop() || test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) - break; - - if (!dev->initialized) - continue; - - if (dev->search_count == 0) - continue; - - mutex_lock(&dev->mutex); - w1_search_process(dev, W1_SEARCH); - mutex_unlock(&dev->mutex); } atomic_dec(&dev->refcnt); diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c index ed3228017da..36ff40250b6 100644 --- a/drivers/w1/w1_int.c +++ b/drivers/w1/w1_int.c @@ -61,6 +61,9 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl, dev->slave_ttl = slave_ttl; dev->search_count = -1; /* continual scan */ + /* 1 for w1_process to decrement + * 1 for __w1_remove_master_device to decrement + */ atomic_set(&dev->refcnt, 2); INIT_LIST_HEAD(&dev->slist); @@ -109,23 +112,23 @@ int w1_add_master_device(struct w1_bus_master *master) if (!dev) return -ENOMEM; + retval = w1_create_master_attributes(dev); + if (retval) + goto err_out_free_dev; + + memcpy(dev->bus_master, master, sizeof(struct w1_bus_master)); + + dev->initialized = 1; + dev->thread = kthread_run(&w1_process, dev, "%s", dev->name); if (IS_ERR(dev->thread)) { retval = PTR_ERR(dev->thread); dev_err(&dev->dev, "Failed to create new kernel thread. err=%d\n", retval); - goto err_out_free_dev; + goto err_out_rm_attr; } - retval = w1_create_master_attributes(dev); - if (retval) - goto err_out_kill_thread; - - memcpy(dev->bus_master, master, sizeof(struct w1_bus_master)); - - dev->initialized = 1; - mutex_lock(&w1_mlock); list_add(&dev->w1_master_entry, &w1_masters); mutex_unlock(&w1_mlock); @@ -137,8 +140,13 @@ int w1_add_master_device(struct w1_bus_master *master) return 0; +#if 0 /* Thread cleanup code, not required currently. */ err_out_kill_thread: + set_bit(W1_MASTER_NEED_EXIT, &dev->flags); kthread_stop(dev->thread); +#endif +err_out_rm_attr: + w1_destroy_master_attributes(dev); err_out_free_dev: w1_free_dev(dev); -- 2.41.1