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* [PATCH] srcu: remove never used variable
@ 2018-02-22  6:52 zhouzhouyi
  2018-02-22 16:58 ` Paul E. McKenney
  0 siblings, 1 reply; 4+ messages in thread
From: zhouzhouyi @ 2018-02-22  6:52 UTC (permalink / raw)
  To: paulmck, josh, rostedt, mathieu.desnoyers, jiangshanlai,
	linux-kernel
  Cc: Zhouyi Zhou

From: Zhouyi Zhou <zhouzhouyi@gmail.com>

In function srcu_gp_end, the variable idxnext is never used after assign,
remove it and its assign statement.

Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
---
 kernel/rcu/srcutree.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index d5cea81..1241715 100644
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -531,7 +531,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
 	unsigned long flags;
 	unsigned long gpseq;
 	int idx;
-	int idxnext;
 	unsigned long mask;
 	struct srcu_data *sdp;
 	struct srcu_node *snp;
@@ -555,7 +554,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
 
 	/* Initiate callback invocation as needed. */
 	idx = rcu_seq_ctr(gpseq) % ARRAY_SIZE(snp->srcu_have_cbs);
-	idxnext = (idx + 1) % ARRAY_SIZE(snp->srcu_have_cbs);
 	rcu_for_each_node_breadth_first(sp, snp) {
 		spin_lock_irq_rcu_node(snp);
 		cbs = false;
-- 
2.1.4

^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH] srcu: remove never used variable
  2018-02-22  6:52 [PATCH] srcu: remove never used variable zhouzhouyi
@ 2018-02-22 16:58 ` Paul E. McKenney
       [not found]   ` <CAABZP2wt0QLuOFndOFTgRACxZw0jqNNeumE91KpjiFQieg14dA@mail.gmail.com>
  0 siblings, 1 reply; 4+ messages in thread
From: Paul E. McKenney @ 2018-02-22 16:58 UTC (permalink / raw)
  To: zhouzhouyi; +Cc: josh, rostedt, mathieu.desnoyers, jiangshanlai, linux-kernel

On Thu, Feb 22, 2018 at 06:52:37AM +0000, zhouzhouyi@gmail.com wrote:
> From: Zhouyi Zhou <zhouzhouyi@gmail.com>
> 
> In function srcu_gp_end, the variable idxnext is never used after assign,
> remove it and its assign statement.
> 
> Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>

Good catch, but Byungchul Park beat you to it.  Please see commit
a72da917f186 ("srcu: Remove dead code in srcu_gp_end()") in -rcu.

							Thanx, Paul

> ---
>  kernel/rcu/srcutree.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
> index d5cea81..1241715 100644
> --- a/kernel/rcu/srcutree.c
> +++ b/kernel/rcu/srcutree.c
> @@ -531,7 +531,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
>  	unsigned long flags;
>  	unsigned long gpseq;
>  	int idx;
> -	int idxnext;
>  	unsigned long mask;
>  	struct srcu_data *sdp;
>  	struct srcu_node *snp;
> @@ -555,7 +554,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
> 
>  	/* Initiate callback invocation as needed. */
>  	idx = rcu_seq_ctr(gpseq) % ARRAY_SIZE(snp->srcu_have_cbs);
> -	idxnext = (idx + 1) % ARRAY_SIZE(snp->srcu_have_cbs);
>  	rcu_for_each_node_breadth_first(sp, snp) {
>  		spin_lock_irq_rcu_node(snp);
>  		cbs = false;
> -- 
> 2.1.4
> 

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] srcu: remove never used variable
       [not found]   ` <CAABZP2wt0QLuOFndOFTgRACxZw0jqNNeumE91KpjiFQieg14dA@mail.gmail.com>
@ 2018-02-23  1:20     ` Paul E. McKenney
  2018-02-23  1:58       ` Zhouyi Zhou
  0 siblings, 1 reply; 4+ messages in thread
From: Paul E. McKenney @ 2018-02-23  1:20 UTC (permalink / raw)
  To: Zhouyi Zhou
  Cc: josh@joshtriplett.org, rostedt@goodmis.org,
	mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com,
	linux-kernel@vger.kernel.org

On Fri, Feb 23, 2018 at 09:04:05AM +0800, Zhouyi Zhou wrote:
> Thanks Paul for reviewing

And thank you for your interest in SRCU!  I am pretty sure that other
bugs still remain.  ;-)

							Thanx, Paul

> Cheers
> Zhouyi
> 
> On Friday, February 23, 2018, Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> wrote:
> 
> > On Thu, Feb 22, 2018 at 06:52:37AM +0000, zhouzhouyi@gmail.com wrote:
> > > From: Zhouyi Zhou <zhouzhouyi@gmail.com>
> > >
> > > In function srcu_gp_end, the variable idxnext is never used after assign,
> > > remove it and its assign statement.
> > >
> > > Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
> >
> > Good catch, but Byungchul Park beat you to it.  Please see commit
> > a72da917f186 ("srcu: Remove dead code in srcu_gp_end()") in -rcu.
> >
> >                                                         Thanx, Paul
> >
> > > ---
> > >  kernel/rcu/srcutree.c | 2 --
> > >  1 file changed, 2 deletions(-)
> > >
> > > diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
> > > index d5cea81..1241715 100644
> > > --- a/kernel/rcu/srcutree.c
> > > +++ b/kernel/rcu/srcutree.c
> > > @@ -531,7 +531,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
> > >       unsigned long flags;
> > >       unsigned long gpseq;
> > >       int idx;
> > > -     int idxnext;
> > >       unsigned long mask;
> > >       struct srcu_data *sdp;
> > >       struct srcu_node *snp;
> > > @@ -555,7 +554,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
> > >
> > >       /* Initiate callback invocation as needed. */
> > >       idx = rcu_seq_ctr(gpseq) % ARRAY_SIZE(snp->srcu_have_cbs);
> > > -     idxnext = (idx + 1) % ARRAY_SIZE(snp->srcu_have_cbs);
> > >       rcu_for_each_node_breadth_first(sp, snp) {
> > >               spin_lock_irq_rcu_node(snp);
> > >               cbs = false;
> > > --
> > > 2.1.4
> > >
> >
> >

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] srcu: remove never used variable
  2018-02-23  1:20     ` Paul E. McKenney
@ 2018-02-23  1:58       ` Zhouyi Zhou
  0 siblings, 0 replies; 4+ messages in thread
From: Zhouyi Zhou @ 2018-02-23  1:58 UTC (permalink / raw)
  To: Paul McKenney
  Cc: josh@joshtriplett.org, rostedt@goodmis.org,
	mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com,
	linux-kernel@vger.kernel.org

Thanks Paul's encouragement, I will keep studying SRCU code.

On Fri, Feb 23, 2018 at 9:20 AM, Paul E. McKenney
<paulmck@linux.vnet.ibm.com> wrote:
> On Fri, Feb 23, 2018 at 09:04:05AM +0800, Zhouyi Zhou wrote:
>> Thanks Paul for reviewing
>
> And thank you for your interest in SRCU!  I am pretty sure that other
> bugs still remain.  ;-)
>
>                                                         Thanx, Paul
>
>> Cheers
>> Zhouyi
>>
>> On Friday, February 23, 2018, Paul E. McKenney <paulmck@linux.vnet.ibm.com>
>> wrote:
>>
>> > On Thu, Feb 22, 2018 at 06:52:37AM +0000, zhouzhouyi@gmail.com wrote:
>> > > From: Zhouyi Zhou <zhouzhouyi@gmail.com>
>> > >
>> > > In function srcu_gp_end, the variable idxnext is never used after assign,
>> > > remove it and its assign statement.
>> > >
>> > > Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
>> >
>> > Good catch, but Byungchul Park beat you to it.  Please see commit
>> > a72da917f186 ("srcu: Remove dead code in srcu_gp_end()") in -rcu.
>> >
>> >                                                         Thanx, Paul
>> >
>> > > ---
>> > >  kernel/rcu/srcutree.c | 2 --
>> > >  1 file changed, 2 deletions(-)
>> > >
>> > > diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
>> > > index d5cea81..1241715 100644
>> > > --- a/kernel/rcu/srcutree.c
>> > > +++ b/kernel/rcu/srcutree.c
>> > > @@ -531,7 +531,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
>> > >       unsigned long flags;
>> > >       unsigned long gpseq;
>> > >       int idx;
>> > > -     int idxnext;
>> > >       unsigned long mask;
>> > >       struct srcu_data *sdp;
>> > >       struct srcu_node *snp;
>> > > @@ -555,7 +554,6 @@ static void srcu_gp_end(struct srcu_struct *sp)
>> > >
>> > >       /* Initiate callback invocation as needed. */
>> > >       idx = rcu_seq_ctr(gpseq) % ARRAY_SIZE(snp->srcu_have_cbs);
>> > > -     idxnext = (idx + 1) % ARRAY_SIZE(snp->srcu_have_cbs);
>> > >       rcu_for_each_node_breadth_first(sp, snp) {
>> > >               spin_lock_irq_rcu_node(snp);
>> > >               cbs = false;
>> > > --
>> > > 2.1.4
>> > >
>> >
>> >
>

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2018-02-23  1:58 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2018-02-22  6:52 [PATCH] srcu: remove never used variable zhouzhouyi
2018-02-22 16:58 ` Paul E. McKenney
     [not found]   ` <CAABZP2wt0QLuOFndOFTgRACxZw0jqNNeumE91KpjiFQieg14dA@mail.gmail.com>
2018-02-23  1:20     ` Paul E. McKenney
2018-02-23  1:58       ` Zhouyi Zhou

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