From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764730AbcINTyd (ORCPT ); Wed, 14 Sep 2016 15:54:33 -0400 Received: from arroyo.ext.ti.com ([198.47.19.12]:47864 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756232AbcINTy2 (ORCPT ); Wed, 14 Sep 2016 15:54:28 -0400 Subject: Re: [PATCH 6/9] net: ethernet: ti: cpts: clean up event list if event pool is empty To: Richard Cochran References: <20160914130231.3035-1-grygorii.strashko@ti.com> <20160914130231.3035-7-grygorii.strashko@ti.com> <20160914141414.GD28592@localhost.localdomain> CC: "David S. Miller" , , Mugunthan V N , Sekhar Nori , , , WingMan Kwok From: Grygorii Strashko Message-ID: Date: Wed, 14 Sep 2016 22:54:22 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20160914141414.GD28592@localhost.localdomain> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/14/2016 05:14 PM, Richard Cochran wrote: > On Wed, Sep 14, 2016 at 04:02:28PM +0300, Grygorii Strashko wrote: >> From: WingMan Kwok >> >> When a CPTS user does not exit gracefully by disabling cpts >> timestamping and leaving a joined multicast group, the system >> continues to receive and timestamps the ptp packets which eventually >> occupy all the event list entries. When this happns, the added code >> tries to remove some list entries which are expired. >> >> Signed-off-by: WingMan Kwok >> Signed-off-by: Grygorii Strashko >> --- >> drivers/net/ethernet/ti/cpts.c | 30 ++++++++++++++++++++++++++++-- >> 1 file changed, 28 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c >> index 970d4e2..ff8bb85 100644 >> --- a/drivers/net/ethernet/ti/cpts.c >> +++ b/drivers/net/ethernet/ti/cpts.c >> @@ -57,22 +57,48 @@ static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low) >> return -1; >> } >> >> +static int cpts_event_list_clean_up(struct cpts *cpts) > > 5 words, that is quite a mouth full. How about this instead? > > static int cpts_purge_events(struct cpts *cpts); > >> +{ >> + struct list_head *this, *next; >> + struct cpts_event *event; >> + int removed = 0; >> + >> + list_for_each_safe(this, next, &cpts->events) { >> + event = list_entry(this, struct cpts_event, list); >> + if (event_expired(event)) { >> + list_del_init(&event->list); >> + list_add(&event->list, &cpts->pool); >> + ++removed; >> + } >> + } >> + return removed; >> +} >> + >> /* >> * Returns zero if matching event type was found. >> */ >> static int cpts_fifo_read(struct cpts *cpts, int match) >> { >> int i, type = -1; >> + int removed; > > No need for another variable, just change the return code above to > > return removed ? 0 : -1; > > and then you have ... > >> u32 hi, lo; >> struct cpts_event *event; >> >> for (i = 0; i < CPTS_FIFO_DEPTH; i++) { >> if (cpts_fifo_pop(cpts, &hi, &lo)) >> break; >> + >> if (list_empty(&cpts->pool)) { >> - pr_err("cpts: event pool is empty\n"); >> - return -1; >> + removed = cpts_event_list_clean_up(cpts); >> + if (!removed) { >> + dev_err(cpts->dev, >> + "cpts: event pool is empty\n"); >> + return -1; >> + } > > if (cpts_purge_events(cpts)) { > dev_err(cpts->dev, "cpts: event pool empty\n"); > return -1; > } > > Notice how I avoided the ugly line break? > >> + dev_dbg(cpts->dev, >> + "cpts: event pool cleaned up %d\n", removed); >> } >> + >> event = list_first_entry(&cpts->pool, struct cpts_event, list); >> event->tmo = jiffies + 2; >> event->high = hi; >> -- >> 2.9.3 >> > NP here - will update. Thanks for you review. -- regards, -grygorii