[v1,1/1] spinlock: Fix failing build for PREEMPT_RT

Message ID 20240115201935.2326400-1-leobras@redhat.com
State New
Headers
Series [v1,1/1] spinlock: Fix failing build for PREEMPT_RT |

Commit Message

Leonardo Bras Soares Passos Jan. 15, 2024, 8:19 p.m. UTC
  Since 1d71b30e1f85 ("sched.h: Move (spin|rwlock)_needbreak() to
spinlock.h") build fails for PREEMPT_RT, since there is no definition
available of either spin_needbreak() and rwlock_needbreak().

Since it was moved on the mentioned commit, it was placed inside a
!PREEMPT_RT part of the code, making it out of reach for an RT kernel.

Fix this by moving code it a few lines down so it can be reached by an
RT build, where it can also make use of the *_is_contended() definition
added by the spinlock_rt.h.

Fixes: d1d71b30e1f85 ("sched.h: Move (spin|rwlock)_needbreak() to
spinlock.h")
Signed-off-by: Leonardo Bras <leobras@redhat.com>
---
 include/linux/spinlock.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)
  

Comments

Kent Overstreet Jan. 15, 2024, 9:54 p.m. UTC | #1
On Mon, Jan 15, 2024 at 05:19:34PM -0300, Leonardo Bras wrote:
> Since 1d71b30e1f85 ("sched.h: Move (spin|rwlock)_needbreak() to
> spinlock.h") build fails for PREEMPT_RT, since there is no definition
> available of either spin_needbreak() and rwlock_needbreak().
> 
> Since it was moved on the mentioned commit, it was placed inside a
> !PREEMPT_RT part of the code, making it out of reach for an RT kernel.
> 
> Fix this by moving code it a few lines down so it can be reached by an
> RT build, where it can also make use of the *_is_contended() definition
> added by the spinlock_rt.h.
> 
> Fixes: d1d71b30e1f85 ("sched.h: Move (spin|rwlock)_needbreak() to
> spinlock.h")
> Signed-off-by: Leonardo Bras <leobras@redhat.com>

I've picked this up - thanks!
  
Leonardo Bras Soares Passos Jan. 16, 2024, 4:02 a.m. UTC | #2
On Mon, Jan 15, 2024 at 04:54:14PM -0500, Kent Overstreet wrote:
> On Mon, Jan 15, 2024 at 05:19:34PM -0300, Leonardo Bras wrote:
> > Since 1d71b30e1f85 ("sched.h: Move (spin|rwlock)_needbreak() to
> > spinlock.h") build fails for PREEMPT_RT, since there is no definition
> > available of either spin_needbreak() and rwlock_needbreak().
> > 
> > Since it was moved on the mentioned commit, it was placed inside a
> > !PREEMPT_RT part of the code, making it out of reach for an RT kernel.
> > 
> > Fix this by moving code it a few lines down so it can be reached by an
> > RT build, where it can also make use of the *_is_contended() definition
> > added by the spinlock_rt.h.
> > 
> > Fixes: d1d71b30e1f85 ("sched.h: Move (spin|rwlock)_needbreak() to
> > spinlock.h")
> > Signed-off-by: Leonardo Bras <leobras@redhat.com>
> 
> I've picked this up - thanks!
> 

Awesome! Thanks!

Leo
  

Patch

diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index eaac8b0da25b8..3fcd20de6ca88 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -449,6 +449,12 @@  static __always_inline int spin_is_contended(spinlock_t *lock)
 	return raw_spin_is_contended(&lock->rlock);
 }
 
+#define assert_spin_locked(lock)	assert_raw_spin_locked(&(lock)->rlock)
+
+#else  /* !CONFIG_PREEMPT_RT */
+# include <linux/spinlock_rt.h>
+#endif /* CONFIG_PREEMPT_RT */
+
 /*
  * Does a critical section need to be broken due to another
  * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
@@ -480,12 +486,6 @@  static inline int rwlock_needbreak(rwlock_t *lock)
 #endif
 }
 
-#define assert_spin_locked(lock)	assert_raw_spin_locked(&(lock)->rlock)
-
-#else  /* !CONFIG_PREEMPT_RT */
-# include <linux/spinlock_rt.h>
-#endif /* CONFIG_PREEMPT_RT */
-
 /*
  * Pull the atomic_t declaration:
  * (asm-mips/atomic.h needs above definitions)