2019-08-20 08:21:45

by Daniel Vetter

Subject: [PATCH 2/3] lockdep: add might_lock_nested()

Necessary to annotate functions where we might acquire a
mutex_lock_nested() or similar. Needed by i915.

Signed-off-by: Daniel Vetter <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: [email protected]
---
include/linux/lockdep.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 38ea6178df7d..30f6172d6889 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -631,6 +631,13 @@ do { \
lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_); \
lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
} while (0)
+# define might_lock_nested(lock, subclass) \
+do { \
+ typecheck(struct lockdep_map *, &(lock)->dep_map); \
+ lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL, \
+ _THIS_IP_); \
+ lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
+} while (0)

#define lockdep_assert_irqs_enabled() do { \
WARN_ONCE(debug_locks && !current->lockdep_recursion && \
@@ -653,6 +660,7 @@ do { \
#else
# define might_lock(lock) do { } while (0)
# define might_lock_read(lock) do { } while (0)
+# define might_lock_nested(lock, subclass) do { } while (0)
# define lockdep_assert_irqs_enabled() do { } while (0)
# define lockdep_assert_irqs_disabled() do { } while (0)
# define lockdep_assert_in_irq() do { } while (0)
--
2.23.0.rc1

2019-08-23 10:56:02

by Peter Zijlstra

Subject: Re: [PATCH 2/3] lockdep: add might_lock_nested()

On Tue, Aug 20, 2019 at 10:19:50AM +0200, Daniel Vetter wrote:
> Necessary to annotate functions where we might acquire a
> mutex_lock_nested() or similar. Needed by i915.
>
> Signed-off-by: Daniel Vetter <[email protected]>
> Cc: Peter Zijlstra <[email protected]>
> Cc: Ingo Molnar <[email protected]>
> Cc: Will Deacon <[email protected]>
> Cc: [email protected]

Acked-by: Peter Zijlstra (Intel) <[email protected]>

> ---
> include/linux/lockdep.h | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
> index 38ea6178df7d..30f6172d6889 100644
> --- a/include/linux/lockdep.h
> +++ b/include/linux/lockdep.h
> @@ -631,6 +631,13 @@ do { \
> lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_); \
> lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
> } while (0)
> +# define might_lock_nested(lock, subclass) \
> +do { \
> + typecheck(struct lockdep_map *, &(lock)->dep_map); \
> + lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL, \
> + _THIS_IP_); \
> + lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
> +} while (0)
>
> #define lockdep_assert_irqs_enabled() do { \
> WARN_ONCE(debug_locks && !current->lockdep_recursion && \
> @@ -653,6 +660,7 @@ do { \
> #else
> # define might_lock(lock) do { } while (0)
> # define might_lock_read(lock) do { } while (0)
> +# define might_lock_nested(lock, subclass) do { } while (0)
> # define lockdep_assert_irqs_enabled() do { } while (0)
> # define lockdep_assert_irqs_disabled() do { } while (0)
> # define lockdep_assert_in_irq() do { } while (0)
> --
> 2.23.0.rc1
>