tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
devlink: Add Documentation/networking/devlink-health.txt
This patch adds a new file to add information about devlink health
mechanism.
Signed-off-by: Aya Levin <ayal@mellanox.com>
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
authored by
Aya Levin
and committed by
David S. Miller
db2ab7a0
7d91126b
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Documentation/networking/devlink-health.txt
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Documentation/networking/devlink-health.txt
···
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The health mechanism is targeted for Real Time Alerting, in order to know when
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something bad had happened to a PCI device
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- Provide alert debug information
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- Self healing
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- If problem needs vendor support, provide a way to gather all needed debugging
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information.
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The main idea is to unify and centralize driver health reports in the
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generic devlink instance and allow the user to set different
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attributes of the health reporting and recovery procedures.
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The devlink health reporter:
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Device driver creates a "health reporter" per each error/health type.
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Error/Health type can be a known/generic (eg pci error, fw error, rx/tx error)
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or unknown (driver specific).
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For each registered health reporter a driver can issue error/health reports
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asynchronously. All health reports handling is done by devlink.
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Device driver can provide specific callbacks for each "health reporter", e.g.
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- Recovery procedures
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- Diagnostics and object dump procedures
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- OOB initial parameters
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Different parts of the driver can register different types of health reporters
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with different handlers.
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Once an error is reported, devlink health will do the following actions:
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* A log is being send to the kernel trace events buffer
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* Health status and statistics are being updated for the reporter instance
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* Object dump is being taken and saved at the reporter instance (as long as
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there is no other dump which is already stored)
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* Auto recovery attempt is being done. Depends on:
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- Auto-recovery configuration
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- Grace period vs. time passed since last recover
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The user interface:
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User can access/change each reporter's parameters and driver specific callbacks
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via devlink, e.g per error type (per health reporter)
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- Configure reporter's generic parameters (like: disable/enable auto recovery)
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- Invoke recovery procedure
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- Run diagnostics
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- Object dump
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The devlink health interface (via netlink):
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DEVLINK_CMD_HEALTH_REPORTER_GET
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Retrieves status and configuration info per DEV and reporter.
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DEVLINK_CMD_HEALTH_REPORTER_SET
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Allows reporter-related configuration setting.
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DEVLINK_CMD_HEALTH_REPORTER_RECOVER
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Triggers a reporter's recovery procedure.
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DEVLINK_CMD_HEALTH_REPORTER_DIAGNOSE
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Retrieves diagnostics data from a reporter on a device.
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DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET
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Retrieves the last stored dump. Devlink health
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saves a single dump. If an dump is not already stored by the devlink
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for this reporter, devlink generates a new dump.
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dump output is defined by the reporter.
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DEVLINK_CMD_HEALTH_REPORTER_DUMP_CLEAR
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Clears the last saved dump file for the specified reporter.
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netlink
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+--------------------------+
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| |
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| + |
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| | |
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+--------------------------+
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|request for ops
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|(diagnose,
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mlx5_core devlink |recover,
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|dump)
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+--------+ +--------------------------+
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| | | reporter| |
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| | | +---------v----------+ |
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| | ops execution | | | |
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| <----------------------------------+ | |
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| | | | | |
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| | | + ^------------------+ |
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| | | | request for ops |
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| | | | (recover, dump) |
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| | | | |
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| | | +-+------------------+ |
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| | health report | | health handler | |
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| +-------------------------------> | |
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| | | +--------------------+ |
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| | health reporter create | |
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| +----------------------------> |
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+--------+ +--------------------------+