diff mbox

[v6,02/15] seqlock: remove optional mutex

Message ID 1464138802-23503-3-git-send-email-cota@braap.org
State New
Headers show

Commit Message

Emilio Cota May 25, 2016, 1:13 a.m. UTC
This option is unused; besides, it bloats the struct when not needed.
Let's just let writers define their own locks elsewhere.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
---
 cpus.c                 |  2 +-
 include/qemu/seqlock.h | 10 +---------
 2 files changed, 2 insertions(+), 10 deletions(-)

Comments

Sergey Fedorov May 27, 2016, 7:55 p.m. UTC | #1
On 25/05/16 04:13, Emilio G. Cota wrote:
> This option is unused; besides, it bloats the struct when not needed.
> Let's just let writers define their own locks elsewhere.
>
> Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> Reviewed-by: Richard Henderson <rth@twiddle.net>
> Signed-off-by: Emilio G. Cota <cota@braap.org>

Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>

> ---
>  cpus.c                 |  2 +-
>  include/qemu/seqlock.h | 10 +---------
>  2 files changed, 2 insertions(+), 10 deletions(-)
>
> diff --git a/cpus.c b/cpus.c
> index cbeb1f6..dd86da5 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -619,7 +619,7 @@ int cpu_throttle_get_percentage(void)
>  
>  void cpu_ticks_init(void)
>  {
> -    seqlock_init(&timers_state.vm_clock_seqlock, NULL);
> +    seqlock_init(&timers_state.vm_clock_seqlock);
>      vmstate_register(NULL, 0, &vmstate_timers, &timers_state);
>      throttle_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT,
>                                             cpu_throttle_timer_tick, NULL);
> diff --git a/include/qemu/seqlock.h b/include/qemu/seqlock.h
> index 70b01fd..e673482 100644
> --- a/include/qemu/seqlock.h
> +++ b/include/qemu/seqlock.h
> @@ -19,22 +19,17 @@
>  typedef struct QemuSeqLock QemuSeqLock;
>  
>  struct QemuSeqLock {
> -    QemuMutex *mutex;
>      unsigned sequence;
>  };
>  
> -static inline void seqlock_init(QemuSeqLock *sl, QemuMutex *mutex)
> +static inline void seqlock_init(QemuSeqLock *sl)
>  {
> -    sl->mutex = mutex;
>      sl->sequence = 0;
>  }
>  
>  /* Lock out other writers and update the count.  */
>  static inline void seqlock_write_lock(QemuSeqLock *sl)
>  {
> -    if (sl->mutex) {
> -        qemu_mutex_lock(sl->mutex);
> -    }
>      ++sl->sequence;
>  
>      /* Write sequence before updating other fields.  */
> @@ -47,9 +42,6 @@ static inline void seqlock_write_unlock(QemuSeqLock *sl)
>      smp_wmb();
>  
>      ++sl->sequence;
> -    if (sl->mutex) {
> -        qemu_mutex_unlock(sl->mutex);
> -    }
>  }
>  
>  static inline unsigned seqlock_read_begin(QemuSeqLock *sl)
diff mbox

Patch

diff --git a/cpus.c b/cpus.c
index cbeb1f6..dd86da5 100644
--- a/cpus.c
+++ b/cpus.c
@@ -619,7 +619,7 @@  int cpu_throttle_get_percentage(void)
 
 void cpu_ticks_init(void)
 {
-    seqlock_init(&timers_state.vm_clock_seqlock, NULL);
+    seqlock_init(&timers_state.vm_clock_seqlock);
     vmstate_register(NULL, 0, &vmstate_timers, &timers_state);
     throttle_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT,
                                            cpu_throttle_timer_tick, NULL);
diff --git a/include/qemu/seqlock.h b/include/qemu/seqlock.h
index 70b01fd..e673482 100644
--- a/include/qemu/seqlock.h
+++ b/include/qemu/seqlock.h
@@ -19,22 +19,17 @@ 
 typedef struct QemuSeqLock QemuSeqLock;
 
 struct QemuSeqLock {
-    QemuMutex *mutex;
     unsigned sequence;
 };
 
-static inline void seqlock_init(QemuSeqLock *sl, QemuMutex *mutex)
+static inline void seqlock_init(QemuSeqLock *sl)
 {
-    sl->mutex = mutex;
     sl->sequence = 0;
 }
 
 /* Lock out other writers and update the count.  */
 static inline void seqlock_write_lock(QemuSeqLock *sl)
 {
-    if (sl->mutex) {
-        qemu_mutex_lock(sl->mutex);
-    }
     ++sl->sequence;
 
     /* Write sequence before updating other fields.  */
@@ -47,9 +42,6 @@  static inline void seqlock_write_unlock(QemuSeqLock *sl)
     smp_wmb();
 
     ++sl->sequence;
-    if (sl->mutex) {
-        qemu_mutex_unlock(sl->mutex);
-    }
 }
 
 static inline unsigned seqlock_read_begin(QemuSeqLock *sl)