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batman-adv: fix random jitter calculation

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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>
Acked-by: Antonio Quartulli <ordex@autistici.org>
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
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Akinobu Mita 2012-12-26 02:32:10 +00:00 committed by David S. Miller
parent cf0be88057
commit 143cdd8f33
1 changed files with 1 additions and 1 deletions
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2
net/batman-adv/bat_iv_ogm.c
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@ -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);
}