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From: Hiroyuki Mikita <h.mikita89@gmail.com>
To: "Sanford, Robert" <rsanford@akamai.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>,
	Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [dpdk-dev] [PATCH] timer: fix break list when timer_cb reset running timer
Date: Thu, 21 Jul 2016 19:34:35 +0900	[thread overview]
Message-ID: <CAO_n4D38s7xxKjbGomKQt9sqDrnxhro2D8GgqB6ZujR7hbCX0w@mail.gmail.com> (raw)
In-Reply-To: <D3B5501E.142DF%rsanford@akamai.com>

Hi Robert,

Thank you for reviewing.

In the following case, the skip list is broken.
- Timer A and timer B are configured on the same lcore, in the same
pending list.
- The expire time of timer A is earlier than that of timer B.
- rte_timer_manage() is called on the lcore after the expire time of timer B.
- The callback of timer A resets timer B.

In rte_timer_manage() process,
both timers are expired at the same time, so the running list includes
both timers.
States of both timers are transited from PENDING to RUNNING, then
callbacks are executed sequentially.
The callback of timer A resets timer B which is still RUNNING, so
timer B is added to the pending-list.
In this time, timer B is in both the running list and the pending list.
It means that the running list is chained to the pending list. Both
lists are broken.

Regards,
Hiroyuki

  reply	other threads:[~2016-07-21 10:34 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-07-17 18:08 Hiroyuki Mikita
2016-07-20 20:17 ` Sanford, Robert
2016-07-21 10:34   ` Hiroyuki Mikita [this message]
2016-07-22 22:14 ` Sanford, Robert
2016-07-23  8:49   ` Thomas Monjalon
2016-07-25 12:29     ` Sanford, Robert
2016-07-25 14:21       ` Hiroyuki Mikita
2016-07-25 14:43         ` Thomas Monjalon
2016-07-25 15:14           ` Hiroyuki Mikita
2016-07-25 15:21             ` Thomas Monjalon
2016-07-25 15:53   ` Thomas Monjalon

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