Earlier fix for race condition introduced a bug where mutex
wasn't unlocked if message failed to be sent. Fix all of this
by moving locking out of mp_request_sync() altogether.
Fixes: da5957821b ("eal: fix race condition in IPC request")
Cc: stable@dpdk.org
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
We are trying to notify sender that response from current process
should be ignored, but we didn't specify which request this response
was for. Fix by copying request name from the original message.
Fixes: 579a4ccc34 ("eal: ignore IPC messages until init is complete")
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
Previously, we were removing request from the list only if we
have succeeded to send it. This resulted in leaving an invalid
pointer in the request list.
Fix this by only adding new requests to the request list if we
have succeeded in sending them.
Fixes: f05e26051c ("eal: add IPC asynchronous request")
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
Previously, we were adding synchronous requests to request list, we
were doing it after checking if request existed. However, we only
removed the request from the request list if we have succeeded in
sending the request. In case of failed request send, we left an
invalid pointer in the request list.
Fix this by only adding request to the list once we succeed in
sending it.
Fixes: 783b6e5497 ("eal: add synchronous multi-process communication")
Cc: stable@dpdk.org
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
EAL did not stop processing further asynchronous requests on
encountering a request that should trigger the callback. This
resulted in erasing valid requests but not triggering them.
Fix this by stopping the loop once we have a request that
can trigger the callback. Once triggered, we go back to scanning
the request queue until there are no more callbacks to trigger.
Fixes: f05e26051c ("eal: add IPC asynchronous request")
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
This API is similar to the blocking API that is already present,
but reply will be received in a separate callback by the caller
(callback specified at the time of request, rather than registering
for it in advance).
Under the hood, we create a separate thread to deal with replies to
asynchronous requests, that will just wait to be notified by the
main thread, or woken up on a timer.
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
Rename rte_mp_request to rte_mp_request_sync to indicate
that this request will be done synchronously (as opposed to
asynchronous request, which comes in next patch).
Also, fix alphabetical ordering for .map file.
Suggested-by: Thomas Monjalon <thomas@monjalon.net>
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
Originally, there was only one type of request which was used
for multiprocess synchronization (hence the name - sync request).
However, now that we are going to have two types of requests,
synchronous and asynchronous, having it named "sync request" is
very confusing, so we will rename it to "pending request". This
is internal-only, so no externally visible API changes.
Suggested-by: Jianfeng Tan <jianfeng.tan@intel.com>
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
If we receive messages that don't have a callback registered for
them, and we haven't finished initialization yet, it can be reasonably
inferred that we shouldn't have gotten the message in the first
place. Therefore, send requester a special message telling them to
ignore response to this request, as if this process wasn't there.
Since it is not possible for primary process to receive any messages
during initialization, this change in practice only applies to
secondary processes.
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
When sending IPC messages, prevent new sockets from initializing.
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
Currently, filter value is hardcoded and disconnected from actual
value returned by eal_mp_socket_path(). Fix this to generate filter
value by deriving it from eal_mp_socket_path() instead.
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
Unlocking the action list before sending message and locking it
again afterwards introduces a window where a response might
arrive before we have a chance to start waiting on a condition,
resulting in timeouts on valid messages.
Fixes: 783b6e5497 ("eal: add synchronous multi-process communication")
Cc: stable@dpdk.org
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
We need the synchronous way for multi-process communication,
i.e., blockingly waiting for reply message when we send a request
to the peer process.
We add two APIs rte_eal_mp_request() and rte_eal_mp_reply() for
such use case. By invoking rte_eal_mp_request(), a request message
is sent out, and then it waits there for a reply message. The caller
can specify the timeout. And the response messages will be collected
and returned so that the caller can decide how to translate them.
The API rte_eal_mp_reply() is always called by an mp action handler.
Here we add another parameter for rte_eal_mp_t so that the action
handler knows which peer address to reply.
sender-process receiver-process
---------------------- ----------------
thread-n
|_rte_eal_mp_request() ----------> mp-thread
|_timedwait() |_process_msg()
|_action()
|_rte_eal_mp_reply()
mp_thread <---------------------|
|_process_msg()
|_signal(send_thread)
thread-m <----------|
|_collect-reply
* A secondary process is only allowed to talk to the primary process.
* If there are multiple secondary processes for the primary process,
it will send request to peer1, collect response from peer1; then
send request to peer2, collect response from peer2, and so on.
* When thread-n is sending request, thread-m of that process can send
request at the same time.
* For pair <action_name, peer>, we guarantee that only one such request
is on the fly.
Suggested-by: Anatoly Burakov <anatoly.burakov@intel.com>
Suggested-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Previouly, there are three channels for multi-process
(i.e., primary/secondary) communication.
1. Config-file based channel, in which, the primary process writes
info into a pre-defined config file, and the secondary process
reads the info out.
2. vfio submodule has its own channel based on unix socket for the
secondary process to get container fd and group fd from the
primary process.
3. pdump submodule also has its own channel based on unix socket for
packet dump.
It'd be good to have a generic communication channel for multi-process
communication to accommodate the requirements including:
a. Secondary wants to send info to primary, for example, secondary
would like to send request (about some specific vdev to primary).
b. Sending info at any time, instead of just initialization time.
c. Share FDs with the other side, for vdev like vhost, related FDs
(memory region, kick) should be shared.
d. A send message request needs the other side to response immediately.
This patch proposes to create a communication channel, based on datagram
unix socket, for above requirements. Each process will block on a unix
socket waiting for messages from the peers.
Three new APIs are added:
1. rte_eal_mp_action_register() is used to register an action,
indexed by a string, when a component at receiver side would like
to response the messages from the peer processe.
2. rte_eal_mp_action_unregister() is used to unregister the action
if the calling component does not want to response the messages.
3. rte_eal_mp_sendmsg() is used to send a message, and returns
immediately. If there are n secondary processes, the primary
process will send n messages.
Suggested-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Replace the BSD license header with the SPDX tag for files
with only an Intel copyright on them.
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
When primary process is booted with --file-prefix option, the API,
rte_eal_primary_proc_alive(), uses a wrong config file path to
check if primary process is alive.
Fix it by calling helper function to get config file path.
Fixes: dd3e00138d ("eal: check if primary process is alive")
Cc: stable@dpdk.org
Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
This patch adds a new function to the EAL API:
int rte_eal_primary_proc_alive(const char *path);
The function indicates if a primary process is alive right now.
This functionality is implemented by testing for a write-
lock on the config file, and the function tests for a lock.
The use case for this functionality is that a secondary
process can wait until a primary process starts by polling
the function and waiting. When the primary is running, the
secondary continues to poll to detect if the primary process
has quit unexpectedly, the secondary process can detect this.
Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com>
Acked-by: Maryam Tahhan <maryam.tahhan@intel.com>
