From: Jan Kiszka <jan.kiszka@web.de>
To: Ivo van Doorn <ivdoorn@gmail.com>
Cc: Jiri Benc <jbenc@suse.cz>, netdev@vger.kernel.org
Subject: Re: [PATCH] d80211: ieee80211_hw handlers should be allowed to sleep
Date: Wed, 18 Oct 2006 20:10:02 +0200 [thread overview]
Message-ID: <45366DFA.7030707@web.de> (raw)
In-Reply-To: <200610181927.37471.IvDoorn@gmail.com>
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Ivo van Doorn wrote:
> On Wednesday 18 October 2006 15:06, Jiri Benc wrote:
>> On Sat, 7 Oct 2006 11:23:15 +0200, Ivo van Doorn wrote:
>>> --- a/net/d80211/ieee80211.c
>>> +++ b/net/d80211/ieee80211.c
>>> @@ -2075,15 +2075,15 @@ void ieee80211_if_shutdown(struct net_de
>>> case IEEE80211_IF_TYPE_STA:
>>> case IEEE80211_IF_TYPE_IBSS:
>>> sdata->u.sta.state = IEEE80211_DISABLED;
>>> - del_timer_sync(&sdata->u.sta.timer);
>>> + cancel_delayed_work(&sdata->u.sta.work);
>>> if (local->scan_work.data == sdata->dev) {
>>> local->sta_scanning = 0;
>>> cancel_delayed_work(&local->scan_work);
>>> - flush_scheduled_work();
>>> /* see comment in ieee80211_unregister_hw to
>>> * understand why this works */
>>> local->scan_work.data = NULL;
>>> }
>>> + flush_scheduled_work();
>> This is racy. local->scan_work.data can be set to NULL only after
>> flush_scheduled_work().
>
> Would something like the patch below be better?
> It keeps the flush_scheduled_work() at the same location, but a second
> is added in case local->scan_work.data != sdata->dev
>
> Jan, was there any particular reason to move flush_cheduled_work() outside of the if-statement?
It is needed unconditionally now, so I moved it out without knowing
about this side effect. Your approach looks good to me.
>
> Signed-off-by Ivo van Doorn <IvDoorn@gmail.com>
>
> ---
>
> diff --git a/net/d80211/ieee80211.c b/net/d80211/ieee80211.c
> index 32a1ba7..cb1180c 100644
> --- a/net/d80211/ieee80211.c
> +++ b/net/d80211/ieee80211.c
> @@ -2075,7 +2075,7 @@ void ieee80211_if_shutdown(struct net_de
> case IEEE80211_IF_TYPE_STA:
> case IEEE80211_IF_TYPE_IBSS:
> sdata->u.sta.state = IEEE80211_DISABLED;
> - del_timer_sync(&sdata->u.sta.timer);
> + cancel_delayed_work(&sdata->u.sta.work);
> if (local->scan_work.data == sdata->dev) {
> local->sta_scanning = 0;
> cancel_delayed_work(&local->scan_work);
> @@ -2083,7 +2083,8 @@ void ieee80211_if_shutdown(struct net_de
> /* see comment in ieee80211_unregister_hw to
> * understand why this works */
> local->scan_work.data = NULL;
> - }
> + } else
> + flush_scheduled_work();
> break;
> }
> }
> @@ -4605,8 +4606,8 @@ void ieee80211_unregister_hw(struct net_
> flush_scheduled_work();
> /* The scan_work is guaranteed not to be called at this
> * point. It is not scheduled and not running now. It can be
> - * scheduled again only by some sta_timer (all of them are
> - * stopped by now) or under rtnl lock. */
> + * scheduled again only by sta_work (stopped by now) or under
> + * rtnl lock. */
> }
>
> ieee80211_rx_bss_list_deinit(dev);
> diff --git a/net/d80211/ieee80211_i.h b/net/d80211/ieee80211_i.h
> index 89666ec..5b48ce2 100644
> --- a/net/d80211/ieee80211_i.h
> +++ b/net/d80211/ieee80211_i.h
> @@ -240,7 +240,7 @@ struct ieee80211_if_sta {
> IEEE80211_ASSOCIATE, IEEE80211_ASSOCIATED,
> IEEE80211_IBSS_SEARCH, IEEE80211_IBSS_JOINED
> } state;
> - struct timer_list timer;
> + struct work_struct work;
> u8 bssid[ETH_ALEN], prev_bssid[ETH_ALEN];
> u8 ssid[IEEE80211_MAX_SSID_LEN];
> size_t ssid_len;
> @@ -621,7 +621,7 @@ int ieee80211_set_compression(struct iee
> struct net_device *dev, struct sta_info *sta);
> int ieee80211_init_client(struct net_device *dev);
> /* ieee80211_sta.c */
> -void ieee80211_sta_timer(unsigned long ptr);
> +void ieee80211_sta_work(void *ptr);
> void ieee80211_sta_rx_mgmt(struct net_device *dev, struct sk_buff *skb,
> struct ieee80211_rx_status *rx_status);
> int ieee80211_sta_set_ssid(struct net_device *dev, char *ssid, size_t len);
> diff --git a/net/d80211/ieee80211_iface.c b/net/d80211/ieee80211_iface.c
> index 9a187af..4dd480f 100644
> --- a/net/d80211/ieee80211_iface.c
> +++ b/net/d80211/ieee80211_iface.c
> @@ -194,9 +194,7 @@ void ieee80211_if_set_type(struct net_de
> struct ieee80211_if_sta *ifsta;
>
> ifsta = &sdata->u.sta;
> - init_timer(&ifsta->timer);
> - ifsta->timer.data = (unsigned long) dev;
> - ifsta->timer.function = ieee80211_sta_timer;
> + INIT_WORK(&ifsta->work, ieee80211_sta_work, dev);
>
> ifsta->capab = WLAN_CAPABILITY_ESS;
> ifsta->auth_algs = IEEE80211_AUTH_ALG_OPEN |
> diff --git a/net/d80211/ieee80211_sta.c b/net/d80211/ieee80211_sta.c
> index cc336bd..bf74b6b 100644
> --- a/net/d80211/ieee80211_sta.c
> +++ b/net/d80211/ieee80211_sta.c
> @@ -457,7 +457,7 @@ static void ieee80211_authenticate(struc
>
> ieee80211_send_auth(dev, ifsta, 1, NULL, 0, 0);
>
> - mod_timer(&ifsta->timer, jiffies + IEEE80211_AUTH_TIMEOUT);
> + schedule_delayed_work(&ifsta->work, IEEE80211_AUTH_TIMEOUT);
> }
>
>
> @@ -677,7 +677,7 @@ static void ieee80211_associate(struct n
>
> ieee80211_send_assoc(dev, ifsta);
>
> - mod_timer(&ifsta->timer, jiffies + IEEE80211_ASSOC_TIMEOUT);
> + schedule_delayed_work(&ifsta->work, IEEE80211_ASSOC_TIMEOUT);
> }
>
>
> @@ -735,11 +735,11 @@ static void ieee80211_associated(struct
> memset(wrqu.ap_addr.sa_data, 0, ETH_ALEN);
> wrqu.ap_addr.sa_family = ARPHRD_ETHER;
> wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
> - mod_timer(&ifsta->timer,
> - jiffies + IEEE80211_MONITORING_INTERVAL + 30 * HZ);
> + schedule_delayed_work(&ifsta->work,
> + IEEE80211_MONITORING_INTERVAL + 30 * HZ);
> } else {
> - mod_timer(&ifsta->timer,
> - jiffies + IEEE80211_MONITORING_INTERVAL);
> + schedule_delayed_work(&ifsta->work,
> + IEEE80211_MONITORING_INTERVAL);
> }
> }
>
> @@ -1019,8 +1019,8 @@ static void ieee80211_rx_mgmt_deauth(str
> ifsta->state == IEEE80211_ASSOCIATE ||
> ifsta->state == IEEE80211_ASSOCIATED) {
> ifsta->state = IEEE80211_AUTHENTICATE;
> - mod_timer(&ifsta->timer,
> - jiffies + IEEE80211_RETRY_AUTH_INTERVAL);
> + schedule_delayed_work(&ifsta->work,
> + IEEE80211_RETRY_AUTH_INTERVAL);
> }
>
> ieee80211_set_associated(dev, ifsta, 0);
> @@ -1062,8 +1062,8 @@ static void ieee80211_rx_mgmt_disassoc(s
>
> if (ifsta->state == IEEE80211_ASSOCIATED) {
> ifsta->state = IEEE80211_ASSOCIATE;
> - mod_timer(&ifsta->timer,
> - jiffies + IEEE80211_RETRY_AUTH_INTERVAL);
> + schedule_delayed_work(&ifsta->work,
> + IEEE80211_RETRY_AUTH_INTERVAL);
> }
>
> ieee80211_set_associated(dev, ifsta, 0);
> @@ -1829,7 +1829,7 @@ static void ieee80211_sta_expire(struct
> static void ieee80211_sta_merge_ibss(struct net_device *dev,
> struct ieee80211_if_sta *ifsta)
> {
> - mod_timer(&ifsta->timer, jiffies + IEEE80211_IBSS_MERGE_INTERVAL);
> + schedule_delayed_work(&ifsta->work, IEEE80211_IBSS_MERGE_INTERVAL);
>
> ieee80211_sta_expire(dev);
> if (ieee80211_sta_active_ibss(dev))
> @@ -1841,20 +1841,19 @@ static void ieee80211_sta_merge_ibss(str
> }
>
>
> -void ieee80211_sta_timer(unsigned long ptr)
> +void ieee80211_sta_work(void *ptr)
> {
> - struct net_device *dev;
> + struct net_device *dev = ptr;
> struct ieee80211_sub_if_data *sdata;
> struct ieee80211_if_sta *ifsta;
>
> - dev = (struct net_device *) ptr;
> if (!netif_running(dev))
> return;
>
> sdata = IEEE80211_DEV_TO_SUB_IF(dev);
> if (sdata->type != IEEE80211_IF_TYPE_STA &&
> sdata->type != IEEE80211_IF_TYPE_IBSS) {
> - printk(KERN_DEBUG "%s: ieee80211_sta_timer: non-STA interface "
> + printk(KERN_DEBUG "%s: ieee80211_sta_work: non-STA interface "
> "(type=%d)\n", dev->name, sdata->type);
> return;
> }
> @@ -1879,7 +1878,7 @@ void ieee80211_sta_timer(unsigned long p
> ieee80211_sta_merge_ibss(dev, ifsta);
> break;
> default:
> - printk(KERN_DEBUG "ieee80211_sta_timer: Unknown state %d\n",
> + printk(KERN_DEBUG "ieee80211_sta_work: Unknown state %d\n",
> ifsta->state);
> break;
> }
> @@ -2107,7 +2106,7 @@ static int ieee80211_sta_join_ibss(struc
> }
>
> ifsta->state = IEEE80211_IBSS_JOINED;
> - mod_timer(&ifsta->timer, jiffies + IEEE80211_IBSS_MERGE_INTERVAL);
> + schedule_delayed_work(&ifsta->work, IEEE80211_IBSS_MERGE_INTERVAL);
>
> ieee80211_rx_bss_put(dev, bss);
>
> @@ -2224,8 +2223,8 @@ #endif /* CONFIG_D80211_IBSS_DEBUG */
> /* Selected IBSS not found in current scan results - try to scan */
> if (ifsta->state == IEEE80211_IBSS_JOINED &&
> !ieee80211_sta_active_ibss(dev)) {
> - mod_timer(&ifsta->timer,
> - jiffies + IEEE80211_IBSS_MERGE_INTERVAL);
> + schedule_delayed_work(&ifsta->work,
> + IEEE80211_IBSS_MERGE_INTERVAL);
> } else if (time_after(jiffies, local->last_scan_completed +
> IEEE80211_SCAN_INTERVAL)) {
> printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
> @@ -2253,7 +2252,7 @@ #endif /* CONFIG_D80211_IBSS_DEBUG */
> }
>
> ifsta->state = IEEE80211_IBSS_SEARCH;
> - mod_timer(&ifsta->timer, jiffies + interval);
> + schedule_delayed_work(&ifsta->work, interval);
> return 0;
> }
>
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next prev parent reply other threads:[~2006-10-18 18:10 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-10-07 9:23 [PATCH] d80211: ieee80211_hw handlers should be allowed to sleep Ivo van Doorn
2006-10-18 13:06 ` Jiri Benc
2006-10-18 17:27 ` Ivo van Doorn
2006-10-18 18:10 ` Jan Kiszka [this message]
2006-10-19 16:01 ` Jiri Benc
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