From mboxrd@z Thu Jan 1 00:00:00 1970 From: rmk+kernel@arm.linux.org.uk (Russell King) Date: Sun, 27 Apr 2014 00:02:23 +0100 Subject: [PATCH RFC 8/8] component: track components via array rather than list In-Reply-To: <20140426230025.GZ26756@n2100.arm.linux.org.uk> References: <20140426230025.GZ26756@n2100.arm.linux.org.uk> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Since we now have an array which defines each component, maintain the components to be bound in the array rather than a separate list. We also need duplicate tracking so we can eliminate multiple bind calls for the same component: we preserve the list-based component order in that the first match which adds the component determines its position. Signed-off-by: Russell King --- drivers/base/component.c | 140 +++++++++++++++++++++-------------------------- 1 file changed, 62 insertions(+), 78 deletions(-) diff --git a/drivers/base/component.c b/drivers/base/component.c index 34e88e23d395..5ca32c60147a 100644 --- a/drivers/base/component.c +++ b/drivers/base/component.c @@ -18,18 +18,21 @@ #include #include +struct component; + struct component_match { size_t alloc; size_t num; struct { void *data; int (*fn)(struct device *, void *); + struct component *component; + bool duplicate; } compare[0]; }; struct master { struct list_head node; - struct list_head components; bool bound; const struct component_master_ops *ops; @@ -39,7 +42,6 @@ struct master { struct component { struct list_head node; - struct list_head master_node; struct master *master; bool bound; @@ -63,46 +65,20 @@ static struct master *__master_find(struct device *dev, return NULL; } -/* Attach an unattached component to a master. */ -static void component_attach_master(struct master *master, struct component *c) -{ - c->master = master; - - list_add_tail(&c->master_node, &master->components); -} - -/* Detach a component from a master. */ -static void component_detach_master(struct master *master, struct component *c) -{ - list_del(&c->master_node); - - c->master = NULL; -} - -/* - * Add a component to a master, finding the component via the compare - * function and compare data. This is safe to call for duplicate matches - * and will not result in the same component being added multiple times. - */ -static int component_master_add_child(struct master *master, +static struct component *find_component(struct master *master, int (*compare)(struct device *, void *), void *compare_data) { struct component *c; - int ret = -ENXIO; list_for_each_entry(c, &component_list, node) { if (c->master && c->master != master) continue; - if (compare(c->dev, compare_data)) { - if (!c->master) - component_attach_master(master, c); - ret = 0; - break; - } + if (compare(c->dev, compare_data)) + return c; } - return ret; + return NULL; } static int find_components(struct master *master) @@ -116,26 +92,35 @@ static int find_components(struct master *master) * any components which are found to this master. */ for (i = 0; i < match->num; i++) { - ret = component_master_add_child(master, - match->compare[i].fn, - match->compare[i].data); - if (ret) + struct component *c; + + if (match->compare[i].component) + continue; + + c = find_component(master, match->compare[i].fn, + match->compare[i].data); + if (!c) { + ret = -ENXIO; break; + } + + /* Attach this component to the master */ + match->compare[i].duplicate = !!c->master; + match->compare[i].component = c; + c->master = master; } return ret; } -/* Detach all attached components from this master */ -static void master_remove_components(struct master *master) +/* Detach component from associated master */ +static void remove_component(struct master *master, struct component *c) { - while (!list_empty(&master->components)) { - struct component *c = list_first_entry(&master->components, - struct component, master_node); - - WARN_ON(c->master != master); + size_t i; - component_detach_master(master, c); - } + /* Detach the component from this master. */ + for (i = 0; i < master->match->num; i++) + if (master->match->compare[i].component == c) + master->match->compare[i].component = NULL; } /* @@ -150,37 +135,25 @@ static int try_to_bring_up_master(struct master *master, { int ret; - if (find_components(master)) { - /* Failed to find all components */ - ret = 0; - goto out; - } + if (find_components(master)) + return 0; - if (component && component->master != master) { - ret = 0; - goto out; - } + if (component && component->master != master) + return 0; - if (!devres_open_group(master->dev, NULL, GFP_KERNEL)) { - ret = -ENOMEM; - goto out; - } + if (!devres_open_group(master->dev, NULL, GFP_KERNEL)) + return -ENOMEM; /* Found all components */ ret = master->ops->bind(master->dev); if (ret < 0) { devres_release_group(master->dev, NULL); dev_info(master->dev, "master bind failed: %d\n", ret); - goto out; + return ret; } master->bound = true; return 1; - -out: - master_remove_components(master); - - return ret; } static int try_to_bring_up_masters(struct component *component) @@ -206,8 +179,6 @@ static void take_down_master(struct master *master) devres_release_group(master->dev, NULL); master->bound = false; } - - master_remove_components(master); } static size_t component_match_size(size_t num) @@ -265,6 +236,7 @@ void component_match_add(struct device *dev, struct component_match **matchptr, match->compare[match->num].fn = compare; match->compare[match->num].data = compare_data; + match->compare[match->num].component = NULL; } int component_master_add_with_match(struct device *dev, @@ -286,7 +258,6 @@ int component_master_add_with_match(struct device *dev, master->dev = dev; master->ops = ops; master->match = match; - INIT_LIST_HEAD(&master->components); /* Add to the list of available masters. */ mutex_lock(&component_mutex); @@ -338,6 +309,7 @@ void component_unbind_all(struct device *master_dev, void *data) { struct master *master; struct component *c; + size_t i; WARN_ON(!mutex_is_locked(&component_mutex)); @@ -345,8 +317,12 @@ void component_unbind_all(struct device *master_dev, void *data) if (!master) return; - list_for_each_entry_reverse(c, &master->components, master_node) - component_unbind(c, master, data); + /* Unbind components in reverse order */ + for (i = master->match->num; i--; ) + if (!master->match->compare[i].duplicate) { + c = master->match->compare[i].component; + component_unbind(c, master, data); + } } EXPORT_SYMBOL_GPL(component_unbind_all); @@ -406,6 +382,7 @@ int component_bind_all(struct device *master_dev, void *data) { struct master *master; struct component *c; + size_t i; int ret = 0; WARN_ON(!mutex_is_locked(&component_mutex)); @@ -414,16 +391,21 @@ int component_bind_all(struct device *master_dev, void *data) if (!master) return -EINVAL; - list_for_each_entry(c, &master->components, master_node) { - ret = component_bind(c, master, data); - if (ret) - break; - } + /* Bind components in match order */ + for (i = 0; i < master->match->num; i++) + if (!master->match->compare[i].duplicate) { + c = master->match->compare[i].component; + ret = component_bind(c, master, data); + if (ret) + break; + } if (ret != 0) { - list_for_each_entry_continue_reverse(c, &master->components, - master_node) - component_unbind(c, master, data); + for (; i--; ) + if (!master->match->compare[i].duplicate) { + c = master->match->compare[i].component; + component_unbind(c, master, data); + } } return ret; @@ -471,8 +453,10 @@ void component_del(struct device *dev, const struct component_ops *ops) break; } - if (component && component->master) + if (component && component->master) { take_down_master(component->master); + remove_component(component->master, component); + } mutex_unlock(&component_mutex); -- 1.8.3.1