kernel/linux.git/net/tipc/eth_media.c, branch linux-7.1.y

tipc: constify dev_addr passing

2021-10-13T16:40:46+00:00

In preparation for netdev->dev_addr being constant make all relevant arguments in tipc constant. Signed-off-by: Jakub Kicinski

tipc: Use is_broadcast_ether_addr() instead of memcmp()

2020-08-03T23:21:46+00:00

Using is_broadcast_ether_addr() instead of directly use memcmp() to determine if the ethernet address is broadcast address. spatch with a semantic match is used to found this problem. (http://coccinelle.lip6.fr/) Signed-off-by: Huang Guobin Acked-by: Ying Xue Signed-off-by: David S. Miller

tipc: introduce variable window congestion control

2019-12-11T01:31:15+00:00

We introduce a simple variable window congestion control for links. The algorithm is inspired by the Reno algorithm, covering both 'slow start', 'congestion avoidance', and 'fast recovery' modes. - We introduce hard lower and upper window limits per link, still different and configurable per bearer type. - We introduce a 'slow start theshold' variable, initially set to the maximum window size. - We let a link start at the minimum congestion window, i.e. in slow start mode, and then let is grow rapidly (+1 per rceived ACK) until it reaches the slow start threshold and enters congestion avoidance mode. - In congestion avoidance mode we increment the congestion window for each window-size number of acked packets, up to a possible maximum equal to the configured maximum window. - For each non-duplicate NACK received, we drop back to fast recovery mode, by setting the both the slow start threshold to and the congestion window to (current_congestion_window / 2). - If the timeout handler finds that the transmit queue has not moved since the previous timeout, it drops the link back to slow start and forces a probe containing the last sent sequence number to the sent to the peer, so that this can discover the stale situation. This change does in reality have effect only on unicast ethernet transport, as we have seen that there is no room whatsoever for increasing the window max size for the UDP bearer. For now, we also choose to keep the limits for the broadcast link unchanged and equal. This algorithm seems to give a 50-100% throughput improvement for messages larger than MTU. Suggested-by: Xin Long Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: make media address offset a common define

2015-02-27T23:18:48+00:00

With the exception of infiniband media which does not use media offsets, the media address is always located at offset 4 in the media info field as defined by the protocol, so we move the definition to the generic bearer.h Signed-off-by: Erik Hugne Signed-off-by: David S. Miller

tipc: rename media/msg related definitions

2015-02-27T23:18:48+00:00

The TIPC_MEDIA_ADDR_SIZE and TIPC_MEDIA_ADDR_OFFSET names are misleading, as they actually define the size and offset of the whole media info field and not the address part. This patch does not have any functional changes. Signed-off-by: Erik Hugne Signed-off-by: David S. Miller

tipc: improve and extend media address conversion functions

2014-05-14T19:19:48+00:00

TIPC currently handles two media specific addresses: Ethernet MAC addresses and InfiniBand addresses. Those are kept in three different formats: 1) A "raw" format as obtained from the device. This format is known only by the media specific adapter code in eth_media.c and ib_media.c. 2) A "generic" internal format, in the form of struct tipc_media_addr, which can be referenced and passed around by the generic media- unaware code. 3) A serialized version of the latter, to be conveyed in neighbor discovery messages. Conversion between the three formats can only be done by the media specific code, so we have function pointers for this purpose in struct tipc_media. Here, the media adapters can install their own conversion functions at startup. We now introduce a new such function, 'raw2addr()', whose purpose is to convert from format 1 to format 2 above. We also try to as far as possible uniform commenting, variable names and usage of these functions, with the purpose of making them more comprehensible. We can now also remove the function tipc_l2_media_addr_set(), whose job is done better by the new function. Finally, we expand the field for serialized addresses (format 3) in discovery messages from 20 to 32 bytes. This is permitted according to the spec, and reduces the risk of problems when we add new media in the future. Signed-off-by: Jon Maloy Reviewed-by: Ying Xue Signed-off-by: David S. Miller

tipc: eliminate code duplication in media layer

2013-12-11T05:17:43+00:00

Currently TIPC supports two L2 media types, Ethernet and Infiniband. Because both these media are accessed through the common net_device API, several functions in the two media adaptation files turn out to be fully or almost identical, leading to unnecessary code duplication. In this commit we extract this common code from the two media files and move them to the generic bearer.c. Additionally, we change the function names to reflect their real role: to access L2 media, irrespective of type. Signed-off-by: Ying Xue Cc: Patrick McHardy Reviewed-by: Paul Gortmaker Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: relocate common functions from media to bearer

2013-12-11T05:17:43+00:00

Currently, registering a TIPC stack handler in the network device layer is done twice, once for Ethernet (eth_media) and Infiniband (ib_media) repectively. But, as this registration is not media specific, we can avoid some code duplication by moving the registering function to the generic bearer layer, to the file bearer.c, and call it only once. The same is true for the network device event notifier. As a side effect, the two workqueues we are using for for setting up/ cleaning up media can now be eliminated. Furthermore, the array for storing the specific media type structs, media_array[], can be entirely deleted. Note that the eth_started and ib_started flags were removed during the code relocation. There is now only one call to bearer_setup and bearer_cleanup, and these can logically not race against each other. Despite its size, this cleanup work incurs no functional changes in TIPC. In particular, it should be noted that the sequence ordering of received packets is unaffected by this change, since packet reception never was subject to any work queue handling in the first place. Signed-off-by: Ying Xue Cc: Patrick McHardy Signed-off-by: Jon Maloy Reviewed-by: Paul Gortmaker Signed-off-by: David S. Miller

tipc: remove TIPC usage of field af_packet_priv in struct net_device

2013-12-11T05:17:42+00:00

TIPC is currently using the field 'af_packet_priv' in struct net_device as a handle to find the bearer instance associated to the given network device. But, by doing so it is blocking other networking cleanups, such as the one discussed here: http://patchwork.ozlabs.org/patch/178044/ This commit removes this usage from TIPC. Instead, we introduce a new field, 'tipc_ptr', to the net_device structure, to serve this purpose. When TIPC bearer is enabled, the bearer object is associated to 'tipc_ptr'. When a TIPC packet arrives in the recv_msg() upcall from a networking device, the bearer object can now be obtained from 'tipc_ptr'. When a bearer is disabled, the bearer object is detached from its underlying network device by setting 'tipc_ptr' to NULL. Additionally, an RCU lock is used to protect the new pointer. Henceforth, the existing tipc_net_lock is used in write mode to serialize write accesses to this pointer, while the new RCU lock is applied on the read side to ensure that the pointer is 100% valid within its wrapped area for all readers. Signed-off-by: Ying Xue Cc: Patrick McHardy Reviewed-by: Paul Gortmaker Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: initiate media type array at compile time

2013-12-11T05:17:42+00:00

Communication media types are abstracted through the struct 'tipc_media', one per media type. These structs are allocated statically inside their respective media file. Furthermore, in order to be able to reach all instances from a central location, we keep a static array with pointers to these structs. This array is currently initialized at runtime, under protection of tipc_net_lock. However, since the contents of the array itself never changes after initialization, we can just as well initialize it at compile time and make it 'const', at the same time making it obvious that no lock protection is needed here. This commit makes the array constant and removes the redundant lock protection. Signed-off-by: Ying Xue Reviewed-by: Paul Gortmaker Signed-off-by: Jon Maloy Signed-off-by: David S. Miller