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* [PATCH] srcu: fix misprint in srcu_funnel_exp_start
@ 2018-01-29 18:23 Ildar Ismagilov
  2018-01-30  5:37 ` Paul E. McKenney
  0 siblings, 1 reply; 3+ messages in thread
From: Ildar Ismagilov @ 2018-01-29 18:23 UTC (permalink / raw)
  Cc: devix84, Paul E. McKenney, Josh Triplett, Steven Rostedt,
	Mathieu Desnoyers, Lai Jiangshan, linux-kernel

Signed-off-by: Ildar Ismagilov <devix84@gmail.com>
---
 kernel/rcu/srcutree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index 6d5880089ff6..1798d1aa60fa 100644
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -599,7 +599,7 @@ static void srcu_funnel_exp_start(struct srcu_struct *sp, struct srcu_node *snp,
 		raw_spin_unlock_irqrestore_rcu_node(snp, flags);
 	}
 	raw_spin_lock_irqsave_rcu_node(sp, flags);
-	if (!ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, s))
+	if (ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, s))
 		sp->srcu_gp_seq_needed_exp = s;
 	raw_spin_unlock_irqrestore_rcu_node(sp, flags);
 }
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] srcu: fix misprint in srcu_funnel_exp_start
  2018-01-29 18:23 [PATCH] srcu: fix misprint in srcu_funnel_exp_start Ildar Ismagilov
@ 2018-01-30  5:37 ` Paul E. McKenney
  2018-01-30 19:17   ` Ildar Ismagilov
  0 siblings, 1 reply; 3+ messages in thread
From: Paul E. McKenney @ 2018-01-30  5:37 UTC (permalink / raw)
  To: Ildar Ismagilov
  Cc: Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan,
	linux-kernel

On Mon, Jan 29, 2018 at 09:23:09PM +0300, Ildar Ismagilov wrote:
> Signed-off-by: Ildar Ismagilov <devix84@gmail.com>

The original does look backwards, now that you mention it, thank you
for sending it.

Did you see any performance differences from this patch?

							Thanx, Paul

> ---
>  kernel/rcu/srcutree.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
> index 6d5880089ff6..1798d1aa60fa 100644
> --- a/kernel/rcu/srcutree.c
> +++ b/kernel/rcu/srcutree.c
> @@ -599,7 +599,7 @@ static void srcu_funnel_exp_start(struct srcu_struct *sp, struct srcu_node *snp,
>  		raw_spin_unlock_irqrestore_rcu_node(snp, flags);
>  	}
>  	raw_spin_lock_irqsave_rcu_node(sp, flags);
> -	if (!ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, s))
> +	if (ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, s))
>  		sp->srcu_gp_seq_needed_exp = s;
>  	raw_spin_unlock_irqrestore_rcu_node(sp, flags);
>  }
> -- 
> 2.11.0
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] srcu: fix misprint in srcu_funnel_exp_start
  2018-01-30  5:37 ` Paul E. McKenney
@ 2018-01-30 19:17   ` Ildar Ismagilov
  0 siblings, 0 replies; 3+ messages in thread
From: Ildar Ismagilov @ 2018-01-30 19:17 UTC (permalink / raw)
  To: Paul E. McKenney
  Cc: Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan,
	linux-kernel

I didn't check the performance, because this misprint has been found
accidentally, during studying of a RCU/SRCU code.

2018-01-30 8:37 GMT+03:00 Paul E. McKenney <paulmck@linux.vnet.ibm.com>:
> On Mon, Jan 29, 2018 at 09:23:09PM +0300, Ildar Ismagilov wrote:
>> Signed-off-by: Ildar Ismagilov <devix84@gmail.com>
>
> The original does look backwards, now that you mention it, thank you
> for sending it.
>
> Did you see any performance differences from this patch?
>
>                                                         Thanx, Paul
>
>> ---
>>  kernel/rcu/srcutree.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
>> index 6d5880089ff6..1798d1aa60fa 100644
>> --- a/kernel/rcu/srcutree.c
>> +++ b/kernel/rcu/srcutree.c
>> @@ -599,7 +599,7 @@ static void srcu_funnel_exp_start(struct srcu_struct *sp, struct srcu_node *snp,
>>               raw_spin_unlock_irqrestore_rcu_node(snp, flags);
>>       }
>>       raw_spin_lock_irqsave_rcu_node(sp, flags);
>> -     if (!ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, s))
>> +     if (ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, s))
>>               sp->srcu_gp_seq_needed_exp = s;
>>       raw_spin_unlock_irqrestore_rcu_node(sp, flags);
>>  }
>> --
>> 2.11.0
>>
>



-- 
Best regards
Ildar

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2018-01-30 19:17 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2018-01-29 18:23 [PATCH] srcu: fix misprint in srcu_funnel_exp_start Ildar Ismagilov
2018-01-30  5:37 ` Paul E. McKenney
2018-01-30 19:17   ` Ildar Ismagilov

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