From: Stephen Boyd <sboyd@codeaurora.org> To: Mike Turquette <mturquette@linaro.org> Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 2/4] clk: Make __clk_lookup() use a list instead of tree search Date: Wed, 3 Sep 2014 18:01:04 -0700 [thread overview] Message-ID: <1409792466-5092-3-git-send-email-sboyd@codeaurora.org> (raw) In-Reply-To: <1409792466-5092-1-git-send-email-sboyd@codeaurora.org> In the near future we're going to move the prepare lock to be a per-clock ww_mutex. __clk_lookup() is called very deep in the set-rate path and we would like to avoid having to take all the locks in the clock tree to search for a clock (basically defeating the purpose of introducing per-clock locks). Introduce a new list that contains all clocks registered in the system and walk this list until the clock is found. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> --- drivers/clk/clk.c | 52 +++++++++++++++++---------------------------- include/linux/clk-private.h | 1 + 2 files changed, 21 insertions(+), 32 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 1feaf708aa49..248a8612a12d 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -33,8 +33,10 @@ static struct task_struct *enable_owner; static int prepare_refcnt; static int enable_refcnt; +static DEFINE_MUTEX(clk_lookup_lock); static HLIST_HEAD(clk_root_list); static HLIST_HEAD(clk_orphan_list); +static HLIST_HEAD(clk_lookup_list); static LIST_HEAD(clk_notifier_list); /*** locking ***/ @@ -680,46 +682,23 @@ out: } EXPORT_SYMBOL_GPL(__clk_is_enabled); -static struct clk *__clk_lookup_subtree(const char *name, struct clk *clk) -{ - struct clk *child; - struct clk *ret; - - if (!strcmp(clk->name, name)) - return clk; - - hlist_for_each_entry(child, &clk->children, child_node) { - ret = __clk_lookup_subtree(name, child); - if (ret) - return ret; - } - - return NULL; -} - struct clk *__clk_lookup(const char *name) { - struct clk *root_clk; - struct clk *ret; + struct clk *clk; if (!name) return NULL; - /* search the 'proper' clk tree first */ - hlist_for_each_entry(root_clk, &clk_root_list, child_node) { - ret = __clk_lookup_subtree(name, root_clk); - if (ret) - return ret; + mutex_lock(&clk_lookup_lock); + hlist_for_each_entry(clk, &clk_lookup_list, lookup_node) { + if (!strcmp(clk->name, name)) + goto found; } + clk = NULL; +found: + mutex_unlock(&clk_lookup_lock); - /* if not found, then search the orphan tree */ - hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) { - ret = __clk_lookup_subtree(name, root_clk); - if (ret) - return ret; - } - - return NULL; + return clk; } /* @@ -1826,6 +1805,11 @@ int __clk_init(struct device *dev, struct clk *clk) clk->parent = __clk_init_parent(clk); + /* Insert into clock lookup list */ + mutex_lock(&clk_lookup_lock); + hlist_add_head(&clk->lookup_node, &clk_lookup_list); + mutex_unlock(&clk_lookup_lock); + /* * Populate clk->parent if parent has already been __clk_init'd. If * parent has not yet been __clk_init'd then place clk in the orphan @@ -2120,6 +2104,10 @@ void clk_unregister(struct clk *clk) hlist_del_init(&clk->child_node); + mutex_lock(&clk_lookup_lock); + hlist_del_init(&clk->lookup_node); + mutex_unlock(&clk_lookup_lock); + if (clk->prepare_count) pr_warn("%s: unregistering prepared clock: %s\n", __func__, clk->name); diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index efbf70b9fd84..3cd98a930006 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -48,6 +48,7 @@ struct clk { unsigned long accuracy; struct hlist_head children; struct hlist_node child_node; + struct hlist_node lookup_node; unsigned int notifier_count; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation
WARNING: multiple messages have this Message-ID (diff)
From: sboyd@codeaurora.org (Stephen Boyd) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 2/4] clk: Make __clk_lookup() use a list instead of tree search Date: Wed, 3 Sep 2014 18:01:04 -0700 [thread overview] Message-ID: <1409792466-5092-3-git-send-email-sboyd@codeaurora.org> (raw) In-Reply-To: <1409792466-5092-1-git-send-email-sboyd@codeaurora.org> In the near future we're going to move the prepare lock to be a per-clock ww_mutex. __clk_lookup() is called very deep in the set-rate path and we would like to avoid having to take all the locks in the clock tree to search for a clock (basically defeating the purpose of introducing per-clock locks). Introduce a new list that contains all clocks registered in the system and walk this list until the clock is found. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> --- drivers/clk/clk.c | 52 +++++++++++++++++---------------------------- include/linux/clk-private.h | 1 + 2 files changed, 21 insertions(+), 32 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 1feaf708aa49..248a8612a12d 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -33,8 +33,10 @@ static struct task_struct *enable_owner; static int prepare_refcnt; static int enable_refcnt; +static DEFINE_MUTEX(clk_lookup_lock); static HLIST_HEAD(clk_root_list); static HLIST_HEAD(clk_orphan_list); +static HLIST_HEAD(clk_lookup_list); static LIST_HEAD(clk_notifier_list); /*** locking ***/ @@ -680,46 +682,23 @@ out: } EXPORT_SYMBOL_GPL(__clk_is_enabled); -static struct clk *__clk_lookup_subtree(const char *name, struct clk *clk) -{ - struct clk *child; - struct clk *ret; - - if (!strcmp(clk->name, name)) - return clk; - - hlist_for_each_entry(child, &clk->children, child_node) { - ret = __clk_lookup_subtree(name, child); - if (ret) - return ret; - } - - return NULL; -} - struct clk *__clk_lookup(const char *name) { - struct clk *root_clk; - struct clk *ret; + struct clk *clk; if (!name) return NULL; - /* search the 'proper' clk tree first */ - hlist_for_each_entry(root_clk, &clk_root_list, child_node) { - ret = __clk_lookup_subtree(name, root_clk); - if (ret) - return ret; + mutex_lock(&clk_lookup_lock); + hlist_for_each_entry(clk, &clk_lookup_list, lookup_node) { + if (!strcmp(clk->name, name)) + goto found; } + clk = NULL; +found: + mutex_unlock(&clk_lookup_lock); - /* if not found, then search the orphan tree */ - hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) { - ret = __clk_lookup_subtree(name, root_clk); - if (ret) - return ret; - } - - return NULL; + return clk; } /* @@ -1826,6 +1805,11 @@ int __clk_init(struct device *dev, struct clk *clk) clk->parent = __clk_init_parent(clk); + /* Insert into clock lookup list */ + mutex_lock(&clk_lookup_lock); + hlist_add_head(&clk->lookup_node, &clk_lookup_list); + mutex_unlock(&clk_lookup_lock); + /* * Populate clk->parent if parent has already been __clk_init'd. If * parent has not yet been __clk_init'd then place clk in the orphan @@ -2120,6 +2104,10 @@ void clk_unregister(struct clk *clk) hlist_del_init(&clk->child_node); + mutex_lock(&clk_lookup_lock); + hlist_del_init(&clk->lookup_node); + mutex_unlock(&clk_lookup_lock); + if (clk->prepare_count) pr_warn("%s: unregistering prepared clock: %s\n", __func__, clk->name); diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index efbf70b9fd84..3cd98a930006 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -48,6 +48,7 @@ struct clk { unsigned long accuracy; struct hlist_head children; struct hlist_node child_node; + struct hlist_node lookup_node; unsigned int notifier_count; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation
next prev parent reply other threads:[~2014-09-04 1:01 UTC|newest] Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top 2014-09-04 1:01 [PATCH v2 0/4] Use wound/wait mutexes in the common clock framework Stephen Boyd 2014-09-04 1:01 ` Stephen Boyd 2014-09-04 1:01 ` [PATCH v2 1/4] clk: Recalc rate and accuracy in underscore functions if not caching Stephen Boyd 2014-09-04 1:01 ` Stephen Boyd 2014-09-04 1:01 ` Stephen Boyd [this message] 2014-09-04 1:01 ` [PATCH v2 2/4] clk: Make __clk_lookup() use a list instead of tree search Stephen Boyd 2014-09-04 1:01 ` [PATCH v2 3/4] clk: Use lockless functions for debug printing Stephen Boyd 2014-09-04 1:01 ` Stephen Boyd 2014-09-04 1:01 ` [PATCH v2 4/4] clk: Use ww_mutexes for clk_prepare_{lock/unlock} Stephen Boyd 2014-09-04 1:01 ` Stephen Boyd 2014-09-04 10:11 ` kiran.padwal 2014-09-04 10:11 ` kiran.padwal at smartplayin.com 2014-09-28 2:41 ` Mike Turquette 2014-09-28 2:41 ` Mike Turquette 2014-09-30 0:12 ` Stephen Boyd 2014-09-30 0:12 ` Stephen Boyd 2014-10-08 1:09 ` Stephen Boyd 2014-10-08 1:09 ` Stephen Boyd 2014-10-09 2:59 ` Mike Turquette 2014-10-09 2:59 ` Mike Turquette 2014-10-10 8:24 ` Peter De Schrijver 2014-10-10 8:24 ` Peter De Schrijver 2014-10-10 8:24 ` Peter De Schrijver 2014-10-11 0:20 ` Stephen Boyd 2014-10-11 0:20 ` Stephen Boyd 2014-10-13 8:23 ` Peter De Schrijver 2014-10-13 8:23 ` Peter De Schrijver 2014-10-13 8:23 ` Peter De Schrijver
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1409792466-5092-3-git-send-email-sboyd@codeaurora.org \ --to=sboyd@codeaurora.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-arm-msm@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=mturquette@linaro.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.