lwn.git/net/tipc/core.h, branch v3.13-rc7

net: misc: Remove extern from function prototypes

2013-10-19T23:12:11+00:00

There are a mix of function prototypes with and without extern in the kernel sources. Standardize on not using extern for function prototypes. Function prototypes don't need to be written with extern. extern is assumed by the compiler. Its use is as unnecessary as using auto to declare automatic/local variables in a block. Signed-off-by: Joe Perches Signed-off-by: David S. Miller

tipc: introduce new TIPC server infrastructure

2013-06-17T22:53:00+00:00

TIPC has two internal servers, one providing a subscription service for topology events, and another providing the configuration interface. These servers have previously been running in BH context, accessing the TIPC-port (aka native) API directly. Apart from these servers, even the TIPC socket implementation is partially built on this API. As this API may simultaneously be called via different paths and in different contexts, a complex and costly lock policiy is required in order to protect TIPC internal resources. To eliminate the need for this complex lock policiy, we introduce a new, generic service API that uses kernel sockets for message passing instead of the native API. Once the toplogy and configuration servers are converted to use this new service, all code pertaining to the native API can be removed. This entails a significant reduction in code amount and complexity, and opens up for a complete rework of the locking policy in TIPC. The new service also solves another problem: As the current topology server works in BH context, it cannot easily be blocked when sending of events fails due to congestion. In such cases events may have to be silently dropped, something that is unacceptable. Therefore, the new service keeps a dedicated outbound queue receiving messages from BH context. Once messages are inserted into this queue, we will immediately schedule a work from a special workqueue. This way, messages/events from the topology server are in reality sent in process context, and the server can block if necessary. Analogously, there is a new workqueue for receiving messages. Once a notification about an arriving message is received in BH context, we schedule a work from the receive workqueue to do the job of receiving the message in process context. As both sending and receive messages are now finished in processes, subscribed events cannot be dropped any more. As of this commit, this new server infrastructure is built, but not actually yet called by the existing TIPC code, but since the conversion changes required in order to use it are significant, the addition is kept here as a separate commit. Signed-off-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

tipc: change socket buffer overflow control to respect sk_rcvbuf

2013-06-17T22:53:00+00:00

As per feedback from the netdev community, we change the buffer overflow protection algorithm in receiving sockets so that it always respects the nominal upper limit set in sk_rcvbuf. Instead of scaling up from a small sk_rcvbuf value, which leads to violation of the configured sk_rcvbuf limit, we now calculate the weighted per-message limit by scaling down from a much bigger value, still in the same field, according to the importance priority of the received message. To allow for administrative tunability of the socket receive buffer size, we create a tipc_rmem sysctl variable to allow the user to configure an even bigger value via sysctl command. It is a size of three (min/default/max) to be consistent with things like tcp_rmem. By default, the value initialized in tipc_rmem[1] is equal to the receive socket size needed by a TIPC_CRITICAL_IMPORTANCE message. This value is also set as the default value of sk_rcvbuf. Originally-by: Jon Maloy Cc: Neil Horman Cc: Jon Maloy [Ying: added sysctl variation to Jon's original patch] Signed-off-by: Ying Xue [PG: don't compile sysctl.c if not config'd; add Documentation] Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

tipc: eliminate configuration for maximum number of name publications

2012-08-20T09:26:31+00:00

Gets rid of the need for users to specify the maximum number of name publications supported by TIPC. TIPC now automatically provides support for the maximum number of name publications to 65535. Signed-off-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

tipc: eliminate configuration for maximum number of name subscriptions

2012-08-20T09:26:31+00:00

Gets rid of the need for users to specify the maximum number of name subscriptions supported by TIPC. TIPC now automatically provides support for the maximum number of name subscriptions to 65535. Signed-off-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

tipc: add __read_mostly annotations to several global variables

2012-08-20T09:26:31+00:00

Added to the following: - tipc_random - tipc_own_addr - tipc_max_ports - tipc_net_id - tipc_remote_management - handler_enabled The above global variables are read often, but written rarely. Use __read_mostly to prevent them being on the same cacheline as another variable which is written to often, which would cause cacheline bouncing. Signed-off-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

tipc: remove pointless name sanity check and tipc_alphabet array

2012-08-20T09:26:30+00:00

There is no real reason to check whether all letters in the given media name and network interface name are within the character set defined in tipc_alphabet array. Even if we eliminate the checking, the rest of checking conditions in tipc_enable_bearer() can ensure we do not enable an invalid or illegal bearer. Signed-off-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

tipc: remove print_buf and deprecated log buffer code

2012-07-13T23:34:43+00:00

The internal log buffer handling functions can now safely be removed since there is no code using it anymore. Requests to interact with the internal tipc log buffer over netlink (in config.c) will report 'obsolete command'. This represents the final removal of any references to a struct print_buf, and the removal of the struct itself. We also get rid of a TIPC specific Kconfig in the process. Finally, log.h is removed since it is not needed anymore. Signed-off-by: Erik Hugne Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker

tipc: phase out most of the struct print_buf usage

2012-07-13T23:33:28+00:00

The tipc_printf is renamed to tipc_snprintf, as the new name describes more what the function actually does. It is also changed to take a buffer and length parameter and return number of characters written to the buffer. All callers of this function that used to pass a print_buf are updated. Final removal of the struct print_buf itself will be done synchronously with the pending removal of the deprecated logging code that also was using it. Functions that build up a response message with a list of ports, nametable contents etc. are changed to return the number of characters written to the output buffer. This information was previously hidden in a field of the print_buf struct, and the number of chars written was fetched with a call to tipc_printbuf_validate. This function is removed since it is no longer referenced nor needed. A generic max size ULTRA_STRING_MAX_LEN is defined, named in keeping with the existing TIPC_TLV_ULTRA_STRING, and the various definitions in port, link and nametable code that largely duplicated this information are removed. This means that amount of link statistics that can be returned is now increased from 2k to 32k. The buffer overflow check is now done just before the reply message is passed over netlink or TIPC to a remote node and the message indicating a truncated buffer is changed to a less dramatic one (less CAPS), placed at the end of the message. Signed-off-by: Erik Hugne Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker

tipc: remove TIPC packet debugging functions and macros

2012-07-13T23:25:16+00:00

The link queue traces and packet level debug functions served a purpose during early development, but are now redundant since there are other, more capable tools available for debugging at the packet level. The TIPC_DEBUG Kconfig option is removed since it does not provide any extra debugging features anymore. This gets rid of a lot of tipc_printf usages, which will make the pending cleanup work of that function easier. Signed-off-by: Erik Hugne Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker