[PATCH 0/2] locking/mutex: Kill mutex_trylock_recursive()

[PATCH 0/2] locking/mutex: Kill mutex_trylock_recursive()

[Sebastian Andrzej Siewior]

Remove mutex_trylock_recursive() from the API and tell checkpatch not to
check it for it anymore.

Sebastian

[PATCH 1/2] locking/mutex: Kill mutex_trylock_recursive()

[Sebastian Andrzej Siewior]

There are not users of mutex_trylock_recursive() in tree as of
v5.11-rc7.

Remove it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 include/linux/mutex.h  | 25 -------------------------
 kernel/locking/mutex.c | 10 ----------
 2 files changed, 35 deletions(-)

diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index dcd185cbfe793..0cd631a197276 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -199,29 +199,4 @@ extern void mutex_unlock(struct mutex *lock);
 
 extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
 
-/*
- * These values are chosen such that FAIL and SUCCESS match the
- * values of the regular mutex_trylock().
- */
-enum mutex_trylock_recursive_enum {
-	MUTEX_TRYLOCK_FAILED    = 0,
-	MUTEX_TRYLOCK_SUCCESS   = 1,
-	MUTEX_TRYLOCK_RECURSIVE,
-};
-
-/**
- * mutex_trylock_recursive - trylock variant that allows recursive locking
- * @lock: mutex to be locked
- *
- * This function should not be used, _ever_. It is purely for hysterical GEM
- * raisins, and once those are gone this will be removed.
- *
- * Returns:
- *  - MUTEX_TRYLOCK_FAILED    - trylock failed,
- *  - MUTEX_TRYLOCK_SUCCESS   - lock acquired,
- *  - MUTEX_TRYLOCK_RECURSIVE - we already owned the lock.
- */
-extern /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
-mutex_trylock_recursive(struct mutex *lock);
-
 #endif /* __LINUX_MUTEX_H */
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 5352ce50a97e3..adb9350907688 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -86,16 +86,6 @@ bool mutex_is_locked(struct mutex *lock)
 }
 EXPORT_SYMBOL(mutex_is_locked);
 
-__must_check enum mutex_trylock_recursive_enum
-mutex_trylock_recursive(struct mutex *lock)
-{
-	if (unlikely(__mutex_owner(lock) == current))
-		return MUTEX_TRYLOCK_RECURSIVE;
-
-	return mutex_trylock(lock);
-}
-EXPORT_SYMBOL(mutex_trylock_recursive);
-
 static inline unsigned long __owner_flags(unsigned long owner)
 {
 	return owner & MUTEX_FLAGS;
-- 
2.30.0

[PATCH 2/2] checkpatch: Don't check for mutex_trylock_recursive()

[Sebastian Andrzej Siewior]

mutex_trylock_recursive() has been removed from the tree, there is no
need to check for it.

Remove traces of mutex_trylock_recursive()'s existence.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 scripts/checkpatch.pl | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 1afe3af1cc097..4b2775fd31d9d 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -7062,12 +7062,6 @@ sub process {
 			}
 		}
 
-# check for mutex_trylock_recursive usage
-		if ($line =~ /mutex_trylock_recursive/) {
-			ERROR("LOCKING",
-			      "recursive locking is bad, do not use this ever.\n" . $herecurr);
-		}
-
 # check for lockdep_set_novalidate_class
 		if ($line =~ /^.\s*lockdep_set_novalidate_class\s*\(/ ||
 		    $line =~ /__lockdep_no_validate__\s*\)/ ) {
-- 
2.30.0

Re: [PATCH 0/2] locking/mutex: Kill mutex_trylock_recursive()

[Peter Zijlstra]

On Wed, Feb 10, 2021 at 09:52:46AM +0100, Sebastian Andrzej Siewior wrote:
> Remove mutex_trylock_recursive() from the API and tell checkpatch not to
> check it for it anymore.

W00t!!

Thanks!

Re: [PATCH 2/2] checkpatch: Don't check for mutex_trylock_recursive()

[Joe Perches]

On Wed, 2021-02-10 at 09:52 +0100, Sebastian Andrzej Siewior wrote:
> mutex_trylock_recursive() has been removed from the tree, there is no
> need to check for it.
> 
> Remove traces of mutex_trylock_recursive()'s existence.

Yay.  Assuming patch 1 is applied, thanks.

> 
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> ---
>  scripts/checkpatch.pl | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 1afe3af1cc097..4b2775fd31d9d 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -7062,12 +7062,6 @@ sub process {
>  			}
>  		}
>  
> 
> -# check for mutex_trylock_recursive usage
> -		if ($line =~ /mutex_trylock_recursive/) {
> -			ERROR("LOCKING",
> -			      "recursive locking is bad, do not use this ever.\n" . $herecurr);
> -		}
> -
>  # check for lockdep_set_novalidate_class
>  		if ($line =~ /^.\s*lockdep_set_novalidate_class\s*\(/ ||
>  		    $line =~ /__lockdep_no_validate__\s*\)/ ) {

[tip: locking/core] checkpatch: Don't check for mutex_trylock_recursive()

[tip-bot2 for Sebastian Andrzej Siewior]

The following commit has been merged into the locking/core branch of tip:

Commit-ID:     6c80408a8a0360fa9223b8c21c0ab8ef42e88bfe
Gitweb:        https://git.kernel.org/tip/6c80408a8a0360fa9223b8c21c0ab8ef42e88bfe
Author:        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
AuthorDate:    Wed, 10 Feb 2021 09:52:48 +01:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 10 Feb 2021 14:44:40 +01:00

checkpatch: Don't check for mutex_trylock_recursive()

mutex_trylock_recursive() has been removed from the tree, there is no
need to check for it.

Remove traces of mutex_trylock_recursive()'s existence.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210210085248.219210-3-bigeasy@linutronix.de
---
 scripts/checkpatch.pl | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 92e888e..15f7f4f 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -7069,12 +7069,6 @@ sub process {
 			}
 		}
 
-# check for mutex_trylock_recursive usage
-		if ($line =~ /mutex_trylock_recursive/) {
-			ERROR("LOCKING",
-			      "recursive locking is bad, do not use this ever.\n" . $herecurr);
-		}
-
 # check for lockdep_set_novalidate_class
 		if ($line =~ /^.\s*lockdep_set_novalidate_class\s*\(/ ||
 		    $line =~ /__lockdep_no_validate__\s*\)/ ) {

[tip: locking/core] locking/mutex: Kill mutex_trylock_recursive()

[tip-bot2 for Sebastian Andrzej Siewior]

The following commit has been merged into the locking/core branch of tip:

Commit-ID:     0f319d49a4167e402b01b2b56639386f0b6846ba
Gitweb:        https://git.kernel.org/tip/0f319d49a4167e402b01b2b56639386f0b6846ba
Author:        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
AuthorDate:    Wed, 10 Feb 2021 09:52:47 +01:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 10 Feb 2021 14:44:40 +01:00

locking/mutex: Kill mutex_trylock_recursive()

There are not users of mutex_trylock_recursive() in tree as of
v5.11-rc7.

Remove it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210210085248.219210-2-bigeasy@linutronix.de
---
 include/linux/mutex.h  | 25 -------------------------
 kernel/locking/mutex.c | 10 ----------
 2 files changed, 35 deletions(-)

diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index dcd185c..0cd631a 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -199,29 +199,4 @@ extern void mutex_unlock(struct mutex *lock);
 
 extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
 
-/*
- * These values are chosen such that FAIL and SUCCESS match the
- * values of the regular mutex_trylock().
- */
-enum mutex_trylock_recursive_enum {
-	MUTEX_TRYLOCK_FAILED    = 0,
-	MUTEX_TRYLOCK_SUCCESS   = 1,
-	MUTEX_TRYLOCK_RECURSIVE,
-};
-
-/**
- * mutex_trylock_recursive - trylock variant that allows recursive locking
- * @lock: mutex to be locked
- *
- * This function should not be used, _ever_. It is purely for hysterical GEM
- * raisins, and once those are gone this will be removed.
- *
- * Returns:
- *  - MUTEX_TRYLOCK_FAILED    - trylock failed,
- *  - MUTEX_TRYLOCK_SUCCESS   - lock acquired,
- *  - MUTEX_TRYLOCK_RECURSIVE - we already owned the lock.
- */
-extern /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
-mutex_trylock_recursive(struct mutex *lock);
-
 #endif /* __LINUX_MUTEX_H */
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 5352ce5..adb9350 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -86,16 +86,6 @@ bool mutex_is_locked(struct mutex *lock)
 }
 EXPORT_SYMBOL(mutex_is_locked);
 
-__must_check enum mutex_trylock_recursive_enum
-mutex_trylock_recursive(struct mutex *lock)
-{
-	if (unlikely(__mutex_owner(lock) == current))
-		return MUTEX_TRYLOCK_RECURSIVE;
-
-	return mutex_trylock(lock);
-}
-EXPORT_SYMBOL(mutex_trylock_recursive);
-
 static inline unsigned long __owner_flags(unsigned long owner)
 {
 	return owner & MUTEX_FLAGS;