From: Waiman Long <longman@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>, Will Deacon <will.deacon@arm.com>
Cc: linux-kernel@vger.kernel.org, Waiman Long <longman@redhat.com>
Subject: [PATCH v2 1/5] locking/lockdep: Remove add_chain_cache_classes()
Date: Tue, 2 Oct 2018 16:19:16 -0400 [thread overview]
Message-ID: <1538511560-10090-2-git-send-email-longman@redhat.com> (raw)
In-Reply-To: <1538511560-10090-1-git-send-email-longman@redhat.com>
The inline function add_chain_cache_classes() is defined, but has no
caller. Just remove it.
Signed-off-by: Waiman Long <longman@redhat.com>
---
kernel/locking/lockdep.c | 70 ----------------------------------------
1 file changed, 70 deletions(-)
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index dd13f865ad40..8f9de7cd11ab 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -2147,76 +2147,6 @@ static int check_no_collision(struct task_struct *curr,
return 1;
}
-/*
- * This is for building a chain between just two different classes,
- * instead of adding a new hlock upon current, which is done by
- * add_chain_cache().
- *
- * This can be called in any context with two classes, while
- * add_chain_cache() must be done within the lock owener's context
- * since it uses hlock which might be racy in another context.
- */
-static inline int add_chain_cache_classes(unsigned int prev,
- unsigned int next,
- unsigned int irq_context,
- u64 chain_key)
-{
- struct hlist_head *hash_head = chainhashentry(chain_key);
- struct lock_chain *chain;
-
- /*
- * Allocate a new chain entry from the static array, and add
- * it to the hash:
- */
-
- /*
- * We might need to take the graph lock, ensure we've got IRQs
- * disabled to make this an IRQ-safe lock.. for recursion reasons
- * lockdep won't complain about its own locking errors.
- */
- if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
- return 0;
-
- if (unlikely(nr_lock_chains >= MAX_LOCKDEP_CHAINS)) {
- if (!debug_locks_off_graph_unlock())
- return 0;
-
- print_lockdep_off("BUG: MAX_LOCKDEP_CHAINS too low!");
- dump_stack();
- return 0;
- }
-
- chain = lock_chains + nr_lock_chains++;
- chain->chain_key = chain_key;
- chain->irq_context = irq_context;
- chain->depth = 2;
- if (likely(nr_chain_hlocks + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) {
- chain->base = nr_chain_hlocks;
- nr_chain_hlocks += chain->depth;
- chain_hlocks[chain->base] = prev - 1;
- chain_hlocks[chain->base + 1] = next -1;
- }
-#ifdef CONFIG_DEBUG_LOCKDEP
- /*
- * Important for check_no_collision().
- */
- else {
- if (!debug_locks_off_graph_unlock())
- return 0;
-
- print_lockdep_off("BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!");
- dump_stack();
- return 0;
- }
-#endif
-
- hlist_add_head_rcu(&chain->entry, hash_head);
- debug_atomic_inc(chain_lookup_misses);
- inc_chains();
-
- return 1;
-}
-
/*
* Adds a dependency chain into chain hashtable. And must be called with
* graph_lock held.
--
2.18.0
next prev parent reply other threads:[~2018-10-02 20:21 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-02 20:19 [PATCH v2 0/5] locking/lockdep: Improve lockdep performance Waiman Long
2018-10-02 20:19 ` Waiman Long [this message]
2018-10-03 7:30 ` [tip:locking/core] locking/lockdep: Remove add_chain_cache_classes() tip-bot for Waiman Long
2018-10-02 20:19 ` [PATCH v2 2/5] locking/lockdep: Eliminate redundant irqs check in __lock_acquire() Waiman Long
2018-10-03 7:31 ` [tip:locking/core] locking/lockdep: Eliminate redundant IRQs " tip-bot for Waiman Long
2018-10-02 20:19 ` [PATCH v2 3/5] locking/lockdep: Add a faster path in __lock_release() Waiman Long
2018-10-03 7:31 ` [tip:locking/core] " tip-bot for Waiman Long
2018-10-02 20:19 ` [PATCH v2 4/5] locking/lockdep: Make class->ops a percpu counter Waiman Long
2018-10-03 7:48 ` Peter Zijlstra
2018-10-03 7:54 ` Ingo Molnar
2018-10-03 8:24 ` Peter Zijlstra
2018-10-03 13:57 ` Waiman Long
2018-10-03 17:07 ` Waiman Long
2018-10-04 10:14 ` Ingo Molnar
2018-10-04 13:05 ` Waiman Long
2018-10-09 10:54 ` [tip:locking/core] locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y tip-bot for Waiman Long
2018-10-02 20:19 ` [PATCH v2 5/5] locking/lockdep: Call lock_release() after releasing the lock Waiman Long
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=1538511560-10090-2-git-send-email-longman@redhat.com \
--to=longman@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=will.deacon@arm.com \
/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: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox