* [B.A.T.M.A.N.] [PATCH 19/29] batman-adv: fix random jitter calculation
[not found] <1356315256-6572-1-git-send-email-akinobu.mita@gmail.com>
@ 2012-12-24 2:14 ` Akinobu Mita
2012-12-25 11:26 ` Antonio Quartulli
2012-12-24 2:14 ` [B.A.T.M.A.N.] [PATCH 20/29] batman-adv: rename random32() to prandom_u32() Akinobu Mita
1 sibling, 1 reply; 7+ messages in thread
From: Akinobu Mita @ 2012-12-24 2:14 UTC (permalink / raw)
To: linux-kernel, akpm
Cc: netdev, b.a.t.m.a.n, Akinobu Mita, Simon Wunderlich,
Marek Lindner, David S. Miller
batadv_iv_ogm_emit_send_time() attempts to calculates a random integer
in the range of 'orig_interval +- BATADV_JITTER' by the below lines.
msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
msecs += (random32() % 2 * BATADV_JITTER);
But it actually gets 'orig_interval' or 'orig_interval - BATADV_JITTER'
because '%' and '*' have same precedence and associativity is
left-to-right.
This adds the parentheses at the appropriate position so that it matches
original intension.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Marek Lindner <lindner_marek@yahoo.de>
Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Cc: Antonio Quartulli <ordex@autistici.org>
Cc: b.a.t.m.a.n@lists.open-mesh.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
---
net/batman-adv/bat_iv_ogm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 9f3925a..7d02ebd 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -123,7 +123,7 @@ batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
unsigned int msecs;
msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
- msecs += (random32() % 2 * BATADV_JITTER);
+ msecs += random32() % (2 * BATADV_JITTER);
return jiffies + msecs_to_jiffies(msecs);
}
--
1.7.11.7
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [B.A.T.M.A.N.] [PATCH 20/29] batman-adv: rename random32() to prandom_u32()
[not found] <1356315256-6572-1-git-send-email-akinobu.mita@gmail.com>
2012-12-24 2:14 ` [B.A.T.M.A.N.] [PATCH 19/29] batman-adv: fix random jitter calculation Akinobu Mita
@ 2012-12-24 2:14 ` Akinobu Mita
2012-12-25 11:30 ` Antonio Quartulli
1 sibling, 1 reply; 7+ messages in thread
From: Akinobu Mita @ 2012-12-24 2:14 UTC (permalink / raw)
To: linux-kernel, akpm
Cc: netdev, b.a.t.m.a.n, Akinobu Mita, Simon Wunderlich,
Marek Lindner, David S. Miller
Use more preferable function name which implies using a pseudo-random
number generator.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Marek Lindner <lindner_marek@yahoo.de>
Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Cc: Antonio Quartulli <ordex@autistici.org>
Cc: b.a.t.m.a.n@lists.open-mesh.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
---
net/batman-adv/bat_iv_ogm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 7d02ebd..bc434c4 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -123,7 +123,7 @@ batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
unsigned int msecs;
msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
- msecs += random32() % (2 * BATADV_JITTER);
+ msecs += prandom_u32() % (2 * BATADV_JITTER);
return jiffies + msecs_to_jiffies(msecs);
}
@@ -131,7 +131,7 @@ batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
/* when do we schedule a ogm packet to be sent */
static unsigned long batadv_iv_ogm_fwd_send_time(void)
{
- return jiffies + msecs_to_jiffies(random32() % (BATADV_JITTER / 2));
+ return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
}
/* apply hop penalty for a normal link */
--
1.7.11.7
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [B.A.T.M.A.N.] [PATCH 19/29] batman-adv: fix random jitter calculation
2012-12-24 2:14 ` [B.A.T.M.A.N.] [PATCH 19/29] batman-adv: fix random jitter calculation Akinobu Mita
@ 2012-12-25 11:26 ` Antonio Quartulli
2012-12-25 21:35 ` Akinobu Mita
0 siblings, 1 reply; 7+ messages in thread
From: Antonio Quartulli @ 2012-12-25 11:26 UTC (permalink / raw)
To: Akinobu Mita
Cc: netdev, b.a.t.m.a.n, linux-kernel, Simon Wunderlich, akpm,
Marek Lindner, David S. Miller
[-- Attachment #1: Type: text/plain, Size: 1159 bytes --]
On Mon, Dec 24, 2012 at 11:14:06AM +0900, Akinobu Mita wrote:
> batadv_iv_ogm_emit_send_time() attempts to calculates a random integer
> in the range of 'orig_interval +- BATADV_JITTER' by the below lines.
>
> msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
> msecs += (random32() % 2 * BATADV_JITTER);
>
> But it actually gets 'orig_interval' or 'orig_interval - BATADV_JITTER'
> because '%' and '*' have same precedence and associativity is
> left-to-right.
>
> This adds the parentheses at the appropriate position so that it matches
> original intension.
>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> Cc: Marek Lindner <lindner_marek@yahoo.de>
> Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
> Cc: Antonio Quartulli <ordex@autistici.org>
> Cc: b.a.t.m.a.n@lists.open-mesh.org
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: netdev@vger.kernel.org
> ---
Acked-by: Antonio Quartulli <ordex@autistici.org>
But I would suggest to apply this change to net, since it is a fix.
Cheers,
--
Antonio Quartulli
..each of us alone is worth nothing..
Ernesto "Che" Guevara
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^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [B.A.T.M.A.N.] [PATCH 20/29] batman-adv: rename random32() to prandom_u32()
2012-12-24 2:14 ` [B.A.T.M.A.N.] [PATCH 20/29] batman-adv: rename random32() to prandom_u32() Akinobu Mita
@ 2012-12-25 11:30 ` Antonio Quartulli
2013-01-02 11:52 ` Marek Lindner
0 siblings, 1 reply; 7+ messages in thread
From: Antonio Quartulli @ 2012-12-25 11:30 UTC (permalink / raw)
To: Akinobu Mita
Cc: netdev, b.a.t.m.a.n, linux-kernel, Simon Wunderlich, akpm,
Marek Lindner, David S. Miller
[-- Attachment #1: Type: text/plain, Size: 619 bytes --]
On Mon, Dec 24, 2012 at 11:14:07AM +0900, Akinobu Mita wrote:
> Use more preferable function name which implies using a pseudo-random
> number generator.
>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> Cc: Marek Lindner <lindner_marek@yahoo.de>
> Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
> Cc: Antonio Quartulli <ordex@autistici.org>
> Cc: b.a.t.m.a.n@lists.open-mesh.org
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: netdev@vger.kernel.org
Acked-by: Antonio Quartulli <ordex@autistici.org>
--
Antonio Quartulli
..each of us alone is worth nothing..
Ernesto "Che" Guevara
[-- Attachment #2: Type: application/pgp-signature, Size: 836 bytes --]
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [B.A.T.M.A.N.] [PATCH 19/29] batman-adv: fix random jitter calculation
2012-12-25 11:26 ` Antonio Quartulli
@ 2012-12-25 21:35 ` Akinobu Mita
2012-12-25 21:37 ` David Miller
0 siblings, 1 reply; 7+ messages in thread
From: Akinobu Mita @ 2012-12-25 21:35 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, b.a.t.m.a.n, linux-kernel, Simon Wunderlich, akpm,
Marek Lindner, David S. Miller
2012/12/25 Antonio Quartulli <ordex@autistici.org>:
> On Mon, Dec 24, 2012 at 11:14:06AM +0900, Akinobu Mita wrote:
>> batadv_iv_ogm_emit_send_time() attempts to calculates a random integer
>> in the range of 'orig_interval +- BATADV_JITTER' by the below lines.
>>
>> msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
>> msecs += (random32() % 2 * BATADV_JITTER);
>>
>> But it actually gets 'orig_interval' or 'orig_interval - BATADV_JITTER'
>> because '%' and '*' have same precedence and associativity is
>> left-to-right.
>>
>> This adds the parentheses at the appropriate position so that it matches
>> original intension.
>>
>> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
>> Cc: Marek Lindner <lindner_marek@yahoo.de>
>> Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
>> Cc: Antonio Quartulli <ordex@autistici.org>
>> Cc: b.a.t.m.a.n@lists.open-mesh.org
>> Cc: "David S. Miller" <davem@davemloft.net>
>> Cc: netdev@vger.kernel.org
>> ---
>
> Acked-by: Antonio Quartulli <ordex@autistici.org>
>
> But I would suggest to apply this change to net, since it is a fix.
I agree.
David, please consider to apply this patch for 3.8-rc*.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [B.A.T.M.A.N.] [PATCH 19/29] batman-adv: fix random jitter calculation
2012-12-25 21:35 ` Akinobu Mita
@ 2012-12-25 21:37 ` David Miller
0 siblings, 0 replies; 7+ messages in thread
From: David Miller @ 2012-12-25 21:37 UTC (permalink / raw)
To: akinobu.mita; +Cc: netdev, b.a.t.m.a.n, linux-kernel, siwu, akpm, lindner_marek
From: Akinobu Mita <akinobu.mita@gmail.com>
Date: Wed, 26 Dec 2012 06:35:37 +0900
> 2012/12/25 Antonio Quartulli <ordex@autistici.org>:
>> On Mon, Dec 24, 2012 at 11:14:06AM +0900, Akinobu Mita wrote:
>>> batadv_iv_ogm_emit_send_time() attempts to calculates a random integer
>>> in the range of 'orig_interval +- BATADV_JITTER' by the below lines.
>>>
>>> msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
>>> msecs += (random32() % 2 * BATADV_JITTER);
>>>
>>> But it actually gets 'orig_interval' or 'orig_interval - BATADV_JITTER'
>>> because '%' and '*' have same precedence and associativity is
>>> left-to-right.
>>>
>>> This adds the parentheses at the appropriate position so that it matches
>>> original intension.
>>>
>>> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
>>> Cc: Marek Lindner <lindner_marek@yahoo.de>
>>> Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
>>> Cc: Antonio Quartulli <ordex@autistici.org>
>>> Cc: b.a.t.m.a.n@lists.open-mesh.org
>>> Cc: "David S. Miller" <davem@davemloft.net>
>>> Cc: netdev@vger.kernel.org
>>> ---
>>
>> Acked-by: Antonio Quartulli <ordex@autistici.org>
>>
>> But I would suggest to apply this change to net, since it is a fix.
>
> I agree.
> David, please consider to apply this patch for 3.8-rc*.
>
All patches I should consider seriously should be properly
reposted for review and inclusion.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [B.A.T.M.A.N.] [PATCH 20/29] batman-adv: rename random32() to prandom_u32()
2012-12-25 11:30 ` Antonio Quartulli
@ 2013-01-02 11:52 ` Marek Lindner
0 siblings, 0 replies; 7+ messages in thread
From: Marek Lindner @ 2013-01-02 11:52 UTC (permalink / raw)
To: b.a.t.m.a.n
Cc: netdev, Akinobu Mita, Simon Wunderlich, linux-kernel, akpm,
David S. Miller
On Tuesday, December 25, 2012 19:30:36 Antonio Quartulli wrote:
> On Mon, Dec 24, 2012 at 11:14:07AM +0900, Akinobu Mita wrote:
> > Use more preferable function name which implies using a pseudo-random
> > number generator.
> >
> > Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> > Cc: Marek Lindner <lindner_marek@yahoo.de>
> > Cc: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
> > Cc: Antonio Quartulli <ordex@autistici.org>
> > Cc: b.a.t.m.a.n@lists.open-mesh.org
> > Cc: "David S. Miller" <davem@davemloft.net>
> > Cc: netdev@vger.kernel.org
>
> Acked-by: Antonio Quartulli <ordex@autistici.org>
Applied in revision 02c5591.
Thanks,
Marek
^ permalink raw reply [flat|nested] 7+ messages in thread
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2012-12-24 2:14 ` [B.A.T.M.A.N.] [PATCH 19/29] batman-adv: fix random jitter calculation Akinobu Mita
2012-12-25 11:26 ` Antonio Quartulli
2012-12-25 21:35 ` Akinobu Mita
2012-12-25 21:37 ` David Miller
2012-12-24 2:14 ` [B.A.T.M.A.N.] [PATCH 20/29] batman-adv: rename random32() to prandom_u32() Akinobu Mita
2012-12-25 11:30 ` Antonio Quartulli
2013-01-02 11:52 ` Marek Lindner
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