- 05 1月, 2017 1 次提交
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由 David Howells 提交于
Fix the way enum values are translated into strings in AF_RXRPC tracepoints. The problem with just doing a lookup in a normal flat array of strings or chars is that external tracing infrastructure can't find it. Rather, TRACE_DEFINE_ENUM must be used. Also sort the enums and string tables to make it easier to keep them in order so that a future patch to __print_symbolic() can be optimised to try a direct lookup into the table first before iterating over it. A couple of _proto() macro calls are removed because they refered to tables that got moved to the tracing infrastructure. The relevant data can be found by way of tracing. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 08 11月, 2016 1 次提交
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由 Paolo Abeni 提交于
A new argument is added to __skb_recv_datagram to provide an explicit skb destructor, invoked under the receive queue lock. The UDP protocol uses such argument to perform memory reclaiming on dequeue, so that the UDP protocol does not set anymore skb->desctructor. Instead explicit memory reclaiming is performed at close() time and when skbs are removed from the receive queue. The in kernel UDP protocol users now need to call a skb_recv_udp() variant instead of skb_recv_datagram() to properly perform memory accounting on dequeue. Overall, this allows acquiring only once the receive queue lock on dequeue. Tested using pktgen with random src port, 64 bytes packet, wire-speed on a 10G link as sender and udp_sink as the receiver, using an l4 tuple rxhash to stress the contention, and one or more udp_sink instances with reuseport. nr sinks vanilla patched 1 440 560 3 2150 2300 6 3650 3800 9 4450 4600 12 6250 6450 v1 -> v2: - do rmem and allocated memory scheduling under the receive lock - do bulk scheduling in first_packet_length() and in udp_destruct_sock() - avoid the typdef for the dequeue callback Suggested-by: NEric Dumazet <edumazet@google.com> Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NPaolo Abeni <pabeni@redhat.com> Acked-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 06 10月, 2016 3 次提交
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由 David Howells 提交于
OpenAFS doesn't always correctly terminate client calls that it makes - this includes calls the OpenAFS servers make to the cache manager service. It should end the client call with either: (1) An ACK that has firstPacket set to one greater than the seq number of the reply DATA packet with the LAST_PACKET flag set (thereby hard-ACK'ing all packets). nAcks should be 0 and acks[] should be empty (ie. no soft-ACKs). (2) An ACKALL packet. OpenAFS, though, may send an ACK packet with firstPacket set to the last seq number or less and soft-ACKs listed for all packets up to and including the last DATA packet. The transmitter, however, is obliged to keep the call live and the soft-ACK'd DATA packets around until they're hard-ACK'd as the receiver is permitted to drop any merely soft-ACK'd packet and request retransmission by sending an ACK packet with a NACK in it. Further, OpenAFS will also terminate a client call by beginning the next client call on the same connection channel. This implicitly completes the previous call. This patch handles implicit ACK of a call on a channel by the reception of the first packet of the next call on that channel. If another call doesn't come along to implicitly ACK a call, then we have to time the call out. There are some bugs there that will be addressed in subsequent patches. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Separate the output of PING ACKs from the output of other sorts of ACK so that if we receive a PING ACK and schedule transmission of a PING RESPONSE ACK, the response doesn't get cancelled by a PING ACK we happen to be scheduling transmission of at the same time. If a PING RESPONSE gets lost, the other side might just sit there waiting for it and refuse to proceed otherwise. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
When a reply is deemed lost, we send a ping to find out the other end received all the request data packets we sent. This should be limited to client calls and we shouldn't do this on service calls. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 30 9月, 2016 5 次提交
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由 David Howells 提交于
Keep that call timeouts as ktimes rather than jiffies so that they can be expressed as functions of RTT. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
The offset field in struct rxrpc_skb_priv is unnecessary as the value can always be calculated. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
When we receive an ACK from the peer that tells us what the peer's receive window (rwind) is, we should reduce ssthresh to rwind if rwind is smaller than ssthresh. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Switch to Congestion Avoidance mode at cwnd == ssthresh rather than relying on cwnd getting incremented beyond ssthresh and the window size, the mode being shifted and then cwnd being corrected. We need to make sure we switch into CA mode so that we stop marking every packet for ACK. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Note the serial number of the packet being ACK'd in the congestion management trace rather than the serial number of the ACK packet. Whilst the serial number of the ACK packet is useful for matching ACK packet in the output of wireshark, the serial number that the ACK is in response to is of more use in working out how different trace lines relate. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 25 9月, 2016 5 次提交
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由 David Howells 提交于
Implement RxRPC slow-start, which is similar to RFC 5681 for TCP. A tracepoint is added to log the state of the congestion management algorithm and the decisions it makes. Notes: (1) Since we send fixed-size DATA packets (apart from the final packet in each phase), counters and calculations are in terms of packets rather than bytes. (2) The ACK packet carries the equivalent of TCP SACK. (3) The FLIGHT_SIZE calculation in RFC 5681 doesn't seem particularly suited to SACK of a small number of packets. It seems that, almost inevitably, by the time three 'duplicate' ACKs have been seen, we have narrowed the loss down to one or two missing packets, and the FLIGHT_SIZE calculation ends up as 2. (4) In rxrpc_resend(), if there was no data that apparently needed retransmission, we transmit a PING ACK to ask the peer to tell us what its Rx window state is. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
If we've sent all the request data in a client call but haven't seen any sign of the reply data yet, schedule an ACK to be sent to the server to find out if the reply data got lost. If the server hasn't yet hard-ACK'd the request data, we send a PING ACK to demand a response to find out whether we need to retransmit. If the server says it has received all of the data, we send an IDLE ACK to tell the server that we haven't received anything in the receive phase as yet. To make this work, a non-immediate PING ACK must carry a delay. I've chosen the same as the IDLE ACK for the moment. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Generate a summary of the Tx buffer packet state when an ACK is received for use in a later patch that does congestion management. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Clear the ACK reason, ACK timer and resend timer when entering the client reply phase when the first DATA packet is received. New ACKs will be proposed once the data is queued. The resend timer is no longer relevant and we need to cancel ACKs scheduled to probe for a lost reply. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Send an immediate ACK if we fill in a hole in the buffer left by an out-of-sequence packet. This may allow the congestion management in the peer to avoid a retransmission if packets got reordered on the wire. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 23 9月, 2016 5 次提交
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由 David Howells 提交于
Add a tracepoint to log proposed ACKs, including whether the proposal is used to update a pending ACK or is discarded in favour of an easlier, higher priority ACK. Whilst we're at it, get rid of the rxrpc_acks() function and access the name array directly. We do, however, need to validate the ACK reason number given to trace_rxrpc_rx_ack() to make sure we don't overrun the array. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Add a tracepoint to log received packets that get discarded due to Rx packet loss. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
When the last packet of data to be transmitted on a call is queued, tx_top is set and then the RXRPC_CALL_TX_LAST flag is set. Unfortunately, this leaves a race in the ACK processing side of things because the flag affects the interpretation of tx_top and also allows us to start receiving reply data before we've finished transmitting. To fix this, make the following changes: (1) rxrpc_queue_packet() now sets a marker in the annotation buffer instead of setting the RXRPC_CALL_TX_LAST flag. (2) rxrpc_rotate_tx_window() detects the marker and sets the flag in the same context as the routines that use it. (3) rxrpc_end_tx_phase() is simplified to just shift the call state. The Tx window must have been rotated before calling to discard the last packet. (4) rxrpc_receiving_reply() is added to handle the arrival of the first DATA packet of a reply to a client call (which is an implicit ACK of the Tx phase). (5) The last part of rxrpc_input_ack() is reordered to perform Tx rotation, then soft-ACK application and then to end the phase if we've rotated the last packet. In the event of a terminal ACK, the soft-ACK application will be skipped as nAcks should be 0. (6) rxrpc_input_ackall() now has to rotate as well as ending the phase. In addition: (7) Alter the transmit tracepoint to log the rotation of the last packet. (8) Remove the no-longer relevant queue_reqack tracepoint note. The ACK-REQUESTED packet header flag is now set as needed when we actually transmit the packet and may vary by retransmission. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
When rxrpc_input_soft_acks() is parsing the soft-ACKs from an ACK packet, it updates the Tx packet annotations in the annotation buffer. If a soft-ACK is an ACK, then we overwrite unack'd, nak'd or to-be-retransmitted states and that is fine; but if the soft-ACK is an NACK, we overwrite the to-be-retransmitted with a nak - which isn't. Instead, we need to let any scheduled retransmission stand if the packet was NAK'd. Note that we don't reissue a resend if the annotation is in the to-be-retransmitted state because someone else must've scheduled the resend already. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
before_eq() and friends should be used to compare serial numbers (when not checking for (non)equality) rather than casting to int, subtracting and checking the result. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 22 9月, 2016 4 次提交
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由 David Howells 提交于
We don't want to send a PING ACK for every new incoming call as that just adds to the network traffic. Instead, we send a PING ACK to the first three that we receive and then once per second thereafter. This could probably be made adjustable in future. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
In addition to sending a PING ACK to gain RTT data, we can set the RXRPC_REQUEST_ACK flag on a DATA packet and get a REQUESTED-ACK ACK. The ACK packet contains the serial number of the packet it is in response to, so we can look through the Tx buffer for a matching DATA packet. This requires that the data packets be stamped with the time of transmission as a ktime rather than having the resend_at time in jiffies. This further requires the resend code to do the resend determination in ktimes and convert to jiffies to set the timer. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Send a PING ACK packet to the peer when we get a new incoming call from a peer we don't have a record for. The PING RESPONSE ACK packet will tell us the following about the peer: (1) its receive window size (2) its MTU sizes (3) its support for jumbo DATA packets (4) if it supports slow start (similar to RFC 5681) (5) an estimate of the RTT This is necessary because the peer won't normally send us an ACK until it gets to the Rx phase and we send it a packet, but we would like to know some of this information before we start sending packets. A pair of tracepoints are added so that RTT determination can be observed. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Add a Tx-phase annotation for packet buffers to indicate that a buffer has already been retransmitted. This will be used by future congestion management. Re-retransmissions of a packet don't affect the congestion window managment in the same way as initial retransmissions. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 17 9月, 2016 7 次提交
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由 David Howells 提交于
Add a configuration option to inject packet loss by discarding approximately every 8th packet received and approximately every 8th DATA packet transmitted. Note that no locking is used, but it shouldn't really matter. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Improve sk_buff tracing within AF_RXRPC by the following means: (1) Use an enum to note the event type rather than plain integers and use an array of event names rather than a big multi ?: list. (2) Distinguish Rx from Tx packets and account them separately. This requires the call phase to be tracked so that we know what we might find in rxtx_buffer[]. (3) Add a parameter to rxrpc_{new,see,get,free}_skb() to indicate the event type. (4) A pair of 'rotate' events are added to indicate packets that are about to be rotated out of the Rx and Tx windows. (5) A pair of 'lost' events are added, along with rxrpc_lose_skb() for packet loss injection recording. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Add a tracepoint to follow the life of packets that get added to a call's receive buffer. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Add a tracepoint to log information from received ACK packets. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Add a tracepoint to follow the insertion of a packet into the transmit buffer, its transmission and its rotation out of the buffer. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
The soft-ACK parser doesn't increment the pointer into the soft-ACK list, resulting in the first ACK/NACK value being applied to all the relevant packets in the Tx queue. This has the potential to miss retransmissions and cause excessive retransmissions. Fix this by incrementing the pointer. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
The code for determining the last packet in rxrpc_recvmsg_data() has been using the RXRPC_CALL_RX_LAST flag to determine if the rx_top pointer points to the last packet or not. This isn't a good idea, however, as the input code may be running simultaneously on another CPU and that sets the flag *before* updating the top pointer. Fix this by the following means: (1) Restrict the use of RXRPC_CALL_RX_LAST to the input routines only. There's otherwise a synchronisation problem between detecting the flag and checking tx_top. This could probably be dealt with by appropriate application of memory barriers, but there's a simpler way. (2) Set RXRPC_CALL_RX_LAST after setting rx_top. (3) Make rxrpc_rotate_rx_window() consult the flags header field of the DATA packet it's about to discard to see if that was the last packet. Use this as the basis for ending the Rx phase. This shouldn't be a problem because the recvmsg side of things is guaranteed to see the packets in order. (4) Make rxrpc_recvmsg_data() return 1 to indicate the end of the data if: (a) the packet it has just processed is marked as RXRPC_LAST_PACKET (b) the call's Rx phase has been ended. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 14 9月, 2016 4 次提交
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由 David Howells 提交于
call->rx_winsize should be initialised to the sysctl setting and the sysctl setting should be limited to the maximum we want to permit. Further, we need to place this in the ACK info instead of the sysctl setting. Furthermore, discard the idea of accepting the subpackets of a jumbo packet that lie beyond the receive window when the first packet of the jumbo is within the window. Just discard the excess subpackets instead. This allows the receive window to be opened up right to the buffer size less one for the dead slot. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Allow tx_winsize to grow when the ACK info packet shows a larger receive window at the other end rather than only permitting it to shrink. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
skb->len should be used rather than skb->data_len when referring to the amount of data in a packet. This will only cause a malfunction in the following cases: (1) We receive a jumbo packet (validation and splitting both are wrong). (2) We see if there's extra ACK info in an ACK packet (we think it's not there and just ignore it). Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
We need to wake up the sender when Tx window rotation due to an incoming ACK makes space in the buffer otherwise the sender is liable to just hang endlessly. This problem isn't noticeable if the Tx phase transfers no more than will fit in a single window or the Tx window rotates fast enough that it doesn't get full. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 08 9月, 2016 3 次提交
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由 David Howells 提交于
Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Make it possible for the data_ready handler called from the UDP transport socket to completely instantiate an rxrpc_call structure and make it immediately live by preallocating all the memory it might need. The idea is to cut out the background thread usage as much as possible. [Note that the preallocated structs are not actually used in this patch - that will be done in a future patch.] If insufficient resources are available in the preallocation buffers, it will be possible to discard the DATA packet in the data_ready handler or schedule a BUSY packet without the need to schedule an attempt at allocation in a background thread. To this end: (1) Preallocate rxrpc_peer, rxrpc_connection and rxrpc_call structs to a maximum number each of the listen backlog size. The backlog size is limited to a maxmimum of 32. Only this many of each can be in the preallocation buffer. (2) For userspace sockets, the preallocation is charged initially by listen() and will be recharged by accepting or rejecting pending new incoming calls. (3) For kernel services {,re,dis}charging of the preallocation buffers is handled manually. Two notifier callbacks have to be provided before kernel_listen() is invoked: (a) An indication that a new call has been instantiated. This can be used to trigger background recharging. (b) An indication that a call is being discarded. This is used when the socket is being released. A function, rxrpc_kernel_charge_accept() is called by the kernel service to preallocate a single call. It should be passed the user ID to be used for that call and a callback to associate the rxrpc call with the kernel service's side of the ID. (4) Discard the preallocation when the socket is closed. (5) Temporarily bump the refcount on the call allocated in rxrpc_incoming_call() so that rxrpc_release_call() can ditch the preallocation ref on service calls unconditionally. This will no longer be necessary once the preallocation is used. Note that this does not yet control the number of active service calls on a client - that will come in a later patch. A future development would be to provide a setsockopt() call that allows a userspace server to manually charge the preallocation buffer. This would allow user call IDs to be provided in advance and the awkward manual accept stage to be bypassed. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
Add two tracepoints: (1) Record the RxRPC protocol header of packets retrieved from the UDP socket by the data_ready handler. (2) Record the outcome of the data_ready handler. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 07 9月, 2016 2 次提交
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由 David Howells 提交于
Add a tracepoint for working out where local aborts happen. Each tracepoint call is labelled with a 3-letter code so that they can be distinguished - and the DATA sequence number is added too where available. rxrpc_kernel_abort_call() also takes a 3-letter code so that AFS can indicate the circumstances when it aborts a call. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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由 David Howells 提交于
rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: NDavid Howells <dhowells@redhat.com>
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