4c984154ef
Current code follows the framework that has been in the transports from the beginning where initial link-side controller connect occurs as part of "creating the controller". Thus that first connect fully talks to the controller and obtains values that can then be used in for blk-mq setup, etc. It also means that everything about the controller is fully know before the "create controller" call returns. This has several weaknesses: - The initial create_ctrl call made by the cli will block for a long time as wire transactions are performed synchronously. This delay becomes longer if errors occur or connectivity is lost and retries need to be performed. - Code wise, it means there is a separate connect path for initial controller connect vs the (same) steps used in the reconnect path. - And as there's separate paths, it means there's separate error handling and retry logic. It also plays havoc with the NEW state (should transition out of it after successful initial connect) vs the RESETTING and CONNECTING (reconnect) states that want to be transitioned to on error. - As there's separate paths, to recover from errors and disruptions, it requires separate recovery/retry paths as well and can severely convolute the controller state. This patch reworks the fc transport to use the same connect paths for the initial connection as it uses for reconnect. This makes a single path for error recovery and handling. This patch: - Removes the driving of the initial connect and replaces it with a state transition to CONNECTING and initiating the reconnect thread. A dummy state transition of RESETTING had to be traversed as a direct transtion of NEW->CONNECTING is not allowed. Given that the controller is "new", the RESETTING transition is a simple no-op. Once in the reconnecting thread, the normal behaviors of ctrl_loss_tmo (max_retries * connect_delay) and dev_loss_tmo will apply before the controller is torn down. - Only if the state transitions couldn't be traversed and the reconnect thread not scheduled, will the controller be torn down while in create_ctrl. - The prior code used the controller state of NEW to indicate whether request queues had been initialized or not. For the admin queue, the request queue is always created, so there's no need to check a state. For IO queues, change to tracking whether a successful io request queue create has occurred (e.g. 1st successful connect). - The initial controller id is initialized to the dynamic controller id used in the initial connect message. It will be overwritten by the real controller id once the controller is connected on the wire. Signed-off-by: James Smart <james.smart@broadcom.com> Signed-off-by: Christoph Hellwig <hch@lst.de> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.