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2006-06-26[NET] netpoll: break recursive loop in netpoll rx pathNeil Horman
The netpoll system currently has a rx to tx path via: netpoll_rx __netpoll_rx arp_reply netpoll_send_skb dev->hard_start_tx This rx->tx loop places network drivers at risk of inadvertently causing a deadlock or BUG halt by recursively trying to acquire a spinlock that is used in both their rx and tx paths (this problem was origionally reported to me in the 3c59x driver, which shares a spinlock between the boomerang_interrupt and boomerang_start_xmit routines). This patch breaks this loop, by queueing arp frames, so that they can be responded to after all receive operations have been completed. Tested by myself and the reported with successful results. Specifically it was tested with netdump. Heres the BZ with details: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=194055 Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-26[NET] netpoll: don't spin forever sending to stopped queuesJeremy Fitzhardinge
When transmitting a skb in netpoll_send_skb(), only retry a limited number of times if the device queue is stopped. Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17[NET]: Add netif_tx_lockHerbert Xu
Various drivers use xmit_lock internally to synchronise with their transmission routines. They do so without setting xmit_lock_owner. This is fine as long as netpoll is not in use. With netpoll it is possible for deadlocks to occur if xmit_lock_owner isn't set. This is because if a printk occurs while xmit_lock is held and xmit_lock_owner is not set can cause netpoll to attempt to take xmit_lock recursively. While it is possible to resolve this by getting netpoll to use trylock, it is suboptimal because netpoll's sole objective is to maximise the chance of getting the printk out on the wire. So delaying or dropping the message is to be avoided as much as possible. So the only alternative is to always set xmit_lock_owner. The following patch does this by introducing the netif_tx_lock family of functions that take care of setting/unsetting xmit_lock_owner. I renamed xmit_lock to _xmit_lock to indicate that it should not be used directly. I didn't provide irq versions of the netif_tx_lock functions since xmit_lock is meant to be a BH-disabling lock. This is pretty much a straight text substitution except for a small bug fix in winbond. It currently uses netif_stop_queue/spin_unlock_wait to stop transmission. This is unsafe as an IRQ can potentially wake up the queue. So it is safer to use netif_tx_disable. The hamradio bits used spin_lock_irq but it is unnecessary as xmit_lock must never be taken in an IRQ handler. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[NET]: Convert RTNL to mutex.Stephen Hemminger
This patch turns the RTNL from a semaphore to a new 2.6.16 mutex and gets rid of some of the leftover legacy. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-17[NET]: Use is_zero_ether_addr() in net/core/netpoll.cKris Katterjohn
This replaces a memcmp() with is_zero_ether_addr(). Signed-off-by: Kris Katterjohn <kjak@users.sourceforge.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[INET_SOCK]: Move struct inet_sock & helper functions to net/inet_sock.hArnaldo Carvalho de Melo
To help in reducing the number of include dependencies, several files were touched as they were getting needed headers indirectly for stuff they use. Thanks also to Alan Menegotto for pointing out that net/dccp/proto.c had linux/dccp.h include twice. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10[NET]: Detect hardware rx checksum faults correctlyHerbert Xu
Here is the patch that introduces the generic skb_checksum_complete which also checks for hardware RX checksum faults. If that happens, it'll call netdev_rx_csum_fault which currently prints out a stack trace with the device name. In future it can turn off RX checksum. I've converted every spot under net/ that does RX checksum checks to use skb_checksum_complete or __skb_checksum_complete with the exceptions of: * Those places where checksums are done bit by bit. These will call netdev_rx_csum_fault directly. * The following have not been completely checked/converted: ipmr ip_vs netfilter dccp This patch is based on patches and suggestions from Stephen Hemminger and David S. Miller. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-03[IPV4]: Replace __in_dev_get with __in_dev_get_rcu/rtnlHerbert Xu
The following patch renames __in_dev_get() to __in_dev_get_rtnl() and introduces __in_dev_get_rcu() to cover the second case. 1) RCU with refcnt should use in_dev_get(). 2) RCU without refcnt should use __in_dev_get_rcu(). 3) All others must hold RTNL and use __in_dev_get_rtnl(). There is one exception in net/ipv4/route.c which is in fact a pre-existing race condition. I've marked it as such so that we remember to fix it. This patch is based on suggestions and prior work by Suzanne Wood and Paul McKenney. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-09[PATCH] more SPIN_LOCK_UNLOCKED -> DEFINE_SPINLOCK conversionsIngo Molnar
This converts the final 20 DEFINE_SPINLOCK holdouts. (another 580 places are already using DEFINE_SPINLOCK). Build tested on x86. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-11[NETPOLL]: remove unused variableMatt Mackall
Remove unused variable Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NETPOLL]: fix initialization/NAPI raceMatt Mackall
This fixes a race during initialization with the NAPI softirq processing by using an RCU approach. This race was discovered when refill_skbs() was added to the setup code. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NETPOLL]: pre-fill skb poolIngo Molnar
we could do one thing (see the patch below): i think it would be useful to fill up the netlogging skb queue straight at initialization time. Especially if netpoll is used for dumping alone, the system might not be in a situation to fill up the queue at the point of crash, so better be a bit more prepared and keep the pipeline filled. [ I've modified this to be called earlier - mpm ] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NETPOLL]: add retry timeoutMatt Mackall
Add limited retry logic to netpoll_send_skb Each time we attempt to send, decrement our per-device retry counter. On every successful send, we reset the counter. We delay 50us between attempts with up to 20000 retries for a total of 1 second. After we've exhausted our retries, subsequent failed attempts will try only once until reset by success. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NETPOLL]: netpoll_send_skb simplifyMatt Mackall
Minor netpoll_send_skb restructuring Restructure to avoid confusing goto and move some bits out of the retry loop. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NETPOLL]: deadlock bugfixJeff Moyer
This fixes an obvious deadlock in the netpoll code. netpoll_rx takes the npinfo->rx_lock. netpoll_rx is also the only caller of arp_reply (through __netpoll_rx). As such, it is not necessary to take this lock. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NETPOLL]: rx_flags bugfixJeff Moyer
Initialize npinfo->rx_flags. The way it stands now, this will have random garbage, and so will incur a locking penalty even when an rx_hook isn't registered and we are not active in the netpoll polling code. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22[NETPOLL]: allow multiple netpoll_clients to register against one interfaceJeff Moyer
This patch provides support for registering multiple netpoll clients to the same network device. Only one of these clients may register an rx_hook, however. In practice, this restriction has not been problematic. It is worth mentioning, though, that the current design can be easily extended to allow for the registration of multiple rx_hooks. The basic idea of the patch is that the rx_np pointer in the netpoll_info structure points to the struct netpoll that has rx_hook filled in. Aside from this one case, there is no need for a pointer from the struct net_device to an individual struct netpoll. A lock is introduced to protect the setting and clearing of the np_rx pointer. The pointer will only be cleared upon netpoll client module removal, and the lock should be uncontested. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22[NETPOLL]: Introduce a netpoll_info structJeff Moyer
This patch introduces a netpoll_info structure, which the struct net_device will now point to instead of pointing to a struct netpoll. The reason for this is two-fold: 1) fields such as the rx_flags, poll_owner, and poll_lock should be maintained per net_device, not per netpoll; and 2) this is a first step in providing support for multiple netpoll clients to register against the same net_device. The struct netpoll is now pointed to by the netpoll_info structure. As such, the previous behaviour of the code is preserved. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!