When a device tree contains a lot of phandles, resolving one takes time because the original method uses a search against all nodes (not just the ones with phandles). Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx> --- drivers/of/base.c | 41 ++++++++++++++++++++++++++++++++++++++--- drivers/of/dynamic.c | 8 ++++++++ drivers/of/of_private.h | 33 +++++++++++++++++++++++++++++++++ include/linux/of.h | 2 ++ 4 files changed, 81 insertions(+), 3 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index 20bbc2f..436a088 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -27,6 +27,7 @@ #include <linux/slab.h> #include <linux/string.h> #include <linux/proc_fs.h> +#include <linux/rhashtable.h> #include "of_private.h" @@ -41,6 +42,18 @@ static const char *of_stdout_options; struct kset *of_kset; +const struct rhashtable_params of_phandle_ht_params = { + .key_offset = offsetof(struct device_node, phandle), /* base offset */ + .key_len = sizeof(phandle), + .head_offset = offsetof(struct device_node, ht_node), + .automatic_shrinking = true, +}; + +struct rhashtable *of_phandle_ht; + +/* default is false */ +bool of_phandle_ht_is_disabled; + /* * Used to protect the of_aliases, to hold off addition of nodes to sysfs. * This mutex must be held whenever modifications are being made to the @@ -162,6 +175,12 @@ int __of_attach_node_post(struct device_node *np) struct property *pp; int rc; + if (of_phandle_ht_available()) { + rc = of_phandle_ht_insert(np); + WARN(rc, "insert to phandle hash fail @%s\n", + of_node_full_name(np)); + } + if (!IS_ENABLED(CONFIG_SYSFS)) return 0; @@ -194,6 +213,17 @@ void __init of_core_init(void) struct device_node *np; int ret; + of_phandle_ht = kzalloc(sizeof(*of_phandle_ht), GFP_KERNEL); + if (!of_phandle_ht) { + pr_warn("devicetree: Failed to allocate hashtable\n"); + return; + } + ret = rhashtable_init(of_phandle_ht, &of_phandle_ht_params); + if (ret) { + pr_warn("devicetree: Failed to initialize hashtable\n"); + return; + } + /* Create the kset, and register existing nodes */ mutex_lock(&of_mutex); of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj); @@ -1073,9 +1103,14 @@ struct device_node *of_find_node_by_phandle(phandle handle) return NULL; raw_spin_lock_irqsave(&devtree_lock, flags); - for_each_of_allnodes(np) - if (np->phandle == handle) - break; + /* when we're ready use the hash table (and not disabled) */ + if (of_phandle_ht_available() && !of_phandle_ht_is_disabled) + np = of_phandle_ht_lookup(handle); + else { /* fallback */ + for_each_of_allnodes(np) + if (np->phandle == handle) + break; + } of_node_get(np); raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index 34ca783..931b905 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -11,6 +11,7 @@ #include <linux/slab.h> #include <linux/string.h> #include <linux/proc_fs.h> +#include <linux/rhashtable.h> #include "of_private.h" @@ -44,6 +45,13 @@ EXPORT_SYMBOL(of_node_put); void __of_detach_node_post(struct device_node *np) { struct property *pp; + int rc; + + if (of_phandle_ht_available()) { + rc = of_phandle_ht_remove(np); + WARN(rc, "remove from phandle hash fail @%s\n", + of_node_full_name(np)); + } if (!IS_ENABLED(CONFIG_SYSFS)) return; diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index 10b0342..386ae71 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -101,4 +101,37 @@ static inline int of_overlay_init(void) } #endif +extern const struct rhashtable_params of_phandle_ht_params; +extern struct rhashtable *of_phandle_ht; + +/* for unittest use */ +extern bool of_phandle_ht_is_disabled; + +static inline bool of_phandle_ht_available(void) +{ + return of_phandle_ht != NULL; +} + +static inline int of_phandle_ht_insert(struct device_node *np) +{ + if (!np || !np->phandle) + return 0; + return rhashtable_insert_fast(of_phandle_ht, + &np->ht_node, of_phandle_ht_params); +} + +static inline int of_phandle_ht_remove(struct device_node *np) +{ + if (!np || !np->phandle) + return 0; + return rhashtable_remove_fast(of_phandle_ht, + &np->ht_node, of_phandle_ht_params); +} + +static inline struct device_node *of_phandle_ht_lookup(phandle handle) +{ + return rhashtable_lookup_fast(of_phandle_ht, + &handle, of_phandle_ht_params); +} + #endif /* _LINUX_OF_PRIVATE_H */ diff --git a/include/linux/of.h b/include/linux/of.h index 18a8e59..9de9a3f 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -25,6 +25,7 @@ #include <linux/notifier.h> #include <linux/property.h> #include <linux/list.h> +#include <linux/rhashtable.h> #include <asm/byteorder.h> #include <asm/errno.h> @@ -52,6 +53,7 @@ struct device_node { phandle phandle; const char *full_name; struct fwnode_handle fwnode; + struct rhash_head ht_node; struct property *properties; struct property *deadprops; /* removed properties */ -- 1.7.12 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html