Re: [PATCH 15/15] seqlock: drop seqcount_ww_mutex_t

[Christian König]

Am 07.04.22 um 11:19 schrieb Daniel Vetter:
On Thu, Apr 07, 2022 at 10:59:46AM +0200, Christian König wrote:
Daniel pointed out that this series removes the last user of
seqcount_ww_mutex_t, so let's drop this.
Signed-off-by: Christian König <christian.koe...@amd.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Will Deacon <w...@kernel.org>
Cc: Waiman Long <long...@redhat.com>
Cc: Boqun Feng <boqun.f...@gmail.com>
Cc: linux-ker...@vger.kernel.org
Yeah I don't think we'll ever need this again, ww_mutex aren't common and
the ww_mutex+seqlock thing wasn't the brighest idea.

Peter/Ingo, assuming you agree, can you ack this for merging through
drm-misc, or want to pick this up later on when the last user disappeared
in Linus' tree?

Mpf, I didn't noticed that removing ww_mutex.h from seqlock.h is causing 
a problem for futex.h.

Just send out a patch to fix this because the build servers are pointing 
out now that drm-misc-next is broken.

Please review ASAP,
Christian.


Cheers, Daniel

---
  include/linux/seqlock.h | 8 ++------
  1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index 37ded6b8fee6..3926e9027947 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -17,7 +17,6 @@
  #include <linux/kcsan-checks.h>
  #include <linux/lockdep.h>
  #include <linux/mutex.h>
-#include <linux/ww_mutex.h>
  #include <linux/preempt.h>
  #include <linux/spinlock.h>
  
@@ -164,7 +163,7 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s)
   * static initializer or init function. This enables lockdep to validate
   * that the write side critical section is properly serialized.
   *
- * LOCKNAME:   raw_spinlock, spinlock, rwlock, mutex, or ww_mutex.
+ * LOCKNAME:   raw_spinlock, spinlock, rwlock or mutex
   */
  
  /*
@@ -184,7 +183,6 @@ static inline void seqcount_lockdep_reader_access(const 
seqcount_t *s)
  #define seqcount_spinlock_init(s, lock)               
seqcount_LOCKNAME_init(s, lock, spinlock)
  #define seqcount_rwlock_init(s, lock)         seqcount_LOCKNAME_init(s, lock, 
rwlock)
  #define seqcount_mutex_init(s, lock)          seqcount_LOCKNAME_init(s, lock, 
mutex)
-#define seqcount_ww_mutex_init(s, lock)                
seqcount_LOCKNAME_init(s, lock, ww_mutex)
  
  /*
   * SEQCOUNT_LOCKNAME()        - Instantiate seqcount_LOCKNAME_t and helpers
@@ -277,7 +275,6 @@ SEQCOUNT_LOCKNAME(raw_spinlock, raw_spinlock_t,  false,    
s->lock,        raw_s
  SEQCOUNT_LOCKNAME(spinlock,     spinlock_t,      __SEQ_RT, s->lock,        spin, 
    spin_lock(s->lock))
  SEQCOUNT_LOCKNAME(rwlock,       rwlock_t,        __SEQ_RT, s->lock,        read, 
    read_lock(s->lock))
  SEQCOUNT_LOCKNAME(mutex,        struct mutex,    true,     s->lock,        
mutex,    mutex_lock(s->lock))
-SEQCOUNT_LOCKNAME(ww_mutex,     struct ww_mutex, true,     &s->lock->base, 
ww_mutex, ww_mutex_lock(s->lock, NULL))
  
  /*
   * SEQCNT_LOCKNAME_ZERO - static initializer for seqcount_LOCKNAME_t
@@ -304,8 +301,7 @@ SEQCOUNT_LOCKNAME(ww_mutex,     struct ww_mutex, true,     
&s->lock->base, ww_mu
        __seqprop_case((s),     raw_spinlock,   prop),                  \
        __seqprop_case((s),     spinlock,       prop),                  \
        __seqprop_case((s),     rwlock,         prop),                  \
-       __seqprop_case((s),     mutex,          prop),                  \
-       __seqprop_case((s),     ww_mutex,       prop))
+       __seqprop_case((s),     mutex,          prop))
  
  #define seqprop_ptr(s)			__seqprop(s, ptr)
  #define seqprop_sequence(s)           __seqprop(s, sequence)
--
2.25.1