Refactored devres.c using lock guards and scoped locks. Changed functions: - devres_for_each_res - devres_add - devres_find - devres_get - devres_remove - release_nodes - release_all - devres_open_group - find_group - devres_remove_group - devres_release_group - devm_krealloc Signed-off-by: Andrea Calabrese <andrea.calabrese@xxxxxxxxxxxxxxxxxxxx> --- Difference from patch V1: devres_remove had a double deletion that caused a warn. Removed it and tested it accordingly to the instructions found on https://download.01.org/0day-ci/archive/20240611/202406111401.915dd40c-oliver.sang@xxxxxxxxx diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 3df0025d12aa..a98720e0cb2b 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -194,14 +194,12 @@ void devres_for_each_res(struct device *dev, dr_release_t release, { struct devres_node *node; struct devres_node *tmp; - unsigned long flags; if (!fn) return; - spin_lock_irqsave(&dev->devres_lock, flags); - list_for_each_entry_safe_reverse(node, tmp, - &dev->devres_head, entry) { + guard(spinlock)(&dev->devres_lock); + list_for_each_entry_safe_reverse(node, tmp, &dev->devres_head, entry) { struct devres *dr = container_of(node, struct devres, node); if (node->release != release) @@ -210,7 +208,6 @@ void devres_for_each_res(struct device *dev, dr_release_t release, continue; fn(dev, dr->data, data); } - spin_unlock_irqrestore(&dev->devres_lock, flags); } EXPORT_SYMBOL_GPL(devres_for_each_res); @@ -243,11 +240,9 @@ EXPORT_SYMBOL_GPL(devres_free); void devres_add(struct device *dev, void *res) { struct devres *dr = container_of(res, struct devres, data); - unsigned long flags; - spin_lock_irqsave(&dev->devres_lock, flags); + guard(spinlock)(&dev->devres_lock); add_dr(dev, &dr->node); - spin_unlock_irqrestore(&dev->devres_lock, flags); } EXPORT_SYMBOL_GPL(devres_add); @@ -287,11 +282,8 @@ void * devres_find(struct device *dev, dr_release_t release, dr_match_t match, void *match_data) { struct devres *dr; - unsigned long flags; - - spin_lock_irqsave(&dev->devres_lock, flags); + guard(spinlock)(&dev->devres_lock); dr = find_dr(dev, release, match, match_data); - spin_unlock_irqrestore(&dev->devres_lock, flags); if (dr) return dr->data; @@ -318,16 +310,14 @@ void * devres_get(struct device *dev, void *new_res, { struct devres *new_dr = container_of(new_res, struct devres, data); struct devres *dr; - unsigned long flags; - - spin_lock_irqsave(&dev->devres_lock, flags); - dr = find_dr(dev, new_dr->node.release, match, match_data); - if (!dr) { - add_dr(dev, &new_dr->node); - dr = new_dr; - new_res = NULL; + scoped_guard(spinlock, &dev->devres_lock) { + dr = find_dr(dev, new_dr->node.release, match, match_data); + if (!dr) { + add_dr(dev, &new_dr->node); + dr = new_dr; + new_res = NULL; + } } - spin_unlock_irqrestore(&dev->devres_lock, flags); devres_free(new_res); return dr->data; @@ -353,15 +343,13 @@ void * devres_remove(struct device *dev, dr_release_t release, dr_match_t match, void *match_data) { struct devres *dr; - unsigned long flags; - - spin_lock_irqsave(&dev->devres_lock, flags); - dr = find_dr(dev, release, match, match_data); - if (dr) { - list_del_init(&dr->node.entry); - devres_log(dev, &dr->node, "REM"); + scoped_guard(spinlock, &dev->devres_lock) { + dr = find_dr(dev, release, match, match_data); + if (dr) { + list_del_init(&dr->node.entry); + devres_log(dev, &dr->node, "REM"); + } } - spin_unlock_irqrestore(&dev->devres_lock, flags); if (dr) return dr->data; @@ -516,7 +504,6 @@ static void release_nodes(struct device *dev, struct list_head *todo) */ int devres_release_all(struct device *dev) { - unsigned long flags; LIST_HEAD(todo); int cnt; @@ -528,9 +515,9 @@ int devres_release_all(struct device *dev) if (list_empty(&dev->devres_head)) return 0; - spin_lock_irqsave(&dev->devres_lock, flags); - cnt = remove_nodes(dev, dev->devres_head.next, &dev->devres_head, &todo); - spin_unlock_irqrestore(&dev->devres_lock, flags); + scoped_guard(spinlock, &dev->devres_lock) { + cnt = remove_nodes(dev, dev->devres_head.next, &dev->devres_head, &todo); + } release_nodes(dev, &todo); return cnt; @@ -552,7 +539,6 @@ int devres_release_all(struct device *dev) void * devres_open_group(struct device *dev, void *id, gfp_t gfp) { struct devres_group *grp; - unsigned long flags; grp = kmalloc(sizeof(*grp), gfp); if (unlikely(!grp)) @@ -568,9 +554,8 @@ void * devres_open_group(struct device *dev, void *id, gfp_t gfp) if (id) grp->id = id; - spin_lock_irqsave(&dev->devres_lock, flags); + guard(spinlock)(&dev->devres_lock); add_dr(dev, &grp->node[0]); - spin_unlock_irqrestore(&dev->devres_lock, flags); return grp->id; } EXPORT_SYMBOL_GPL(devres_open_group); @@ -609,17 +594,14 @@ static struct devres_group * find_group(struct device *dev, void *id) void devres_close_group(struct device *dev, void *id) { struct devres_group *grp; - unsigned long flags; - spin_lock_irqsave(&dev->devres_lock, flags); + guard(spinlock)(&dev->devres_lock); grp = find_group(dev, id); if (grp) add_dr(dev, &grp->node[1]); else WARN_ON(1); - - spin_unlock_irqrestore(&dev->devres_lock, flags); } EXPORT_SYMBOL_GPL(devres_close_group); @@ -635,19 +617,16 @@ EXPORT_SYMBOL_GPL(devres_close_group); void devres_remove_group(struct device *dev, void *id) { struct devres_group *grp; - unsigned long flags; - - spin_lock_irqsave(&dev->devres_lock, flags); - - grp = find_group(dev, id); - if (grp) { - list_del_init(&grp->node[0].entry); - list_del_init(&grp->node[1].entry); - devres_log(dev, &grp->node[0], "REM"); - } else - WARN_ON(1); - spin_unlock_irqrestore(&dev->devres_lock, flags); + scoped_guard(spinlock, &dev->devres_lock) { + grp = find_group(dev, id); + if (grp) { + list_del_init(&grp->node[0].entry); + list_del_init(&grp->node[1].entry); + devres_log(dev, &grp->node[0], "REM"); + } else + WARN_ON(1); + } kfree(grp); } @@ -668,11 +647,10 @@ EXPORT_SYMBOL_GPL(devres_remove_group); int devres_release_group(struct device *dev, void *id) { struct devres_group *grp; - unsigned long flags; LIST_HEAD(todo); int cnt = 0; - spin_lock_irqsave(&dev->devres_lock, flags); + guard(spinlock)(&dev->devres_lock); grp = find_group(dev, id); if (grp) { @@ -683,12 +661,9 @@ int devres_release_group(struct device *dev, void *id) end = grp->node[1].entry.next; cnt = remove_nodes(dev, first, end, &todo); - spin_unlock_irqrestore(&dev->devres_lock, flags); - release_nodes(dev, &todo); } else { WARN_ON(1); - spin_unlock_irqrestore(&dev->devres_lock, flags); } return cnt; @@ -860,7 +835,6 @@ void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp) { size_t total_new_size, total_old_size; struct devres *old_dr, *new_dr; - unsigned long flags; if (unlikely(!new_size)) { devm_kfree(dev, ptr); @@ -906,20 +880,17 @@ void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp) * The spinlock protects the linked list against concurrent * modifications but not the resource itself. */ - spin_lock_irqsave(&dev->devres_lock, flags); + scoped_guard(spinlock, &dev->devres_lock) { + old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr); + if (!old_dr) { + kfree(new_dr); + WARN(1, "Memory chunk not managed or managed by a different device."); + return NULL; + } - old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr); - if (!old_dr) { - spin_unlock_irqrestore(&dev->devres_lock, flags); - kfree(new_dr); - WARN(1, "Memory chunk not managed or managed by a different device."); - return NULL; + replace_dr(dev, &old_dr->node, &new_dr->node); } - replace_dr(dev, &old_dr->node, &new_dr->node); - - spin_unlock_irqrestore(&dev->devres_lock, flags); - /* * We can copy the memory contents after releasing the lock as we're * no longer modifying the list links. -- 2.34.1
