ab3f35b226
And change type name of callback as well. The new name is more accurate. Change-Id: I13b63f7d33f60ecea7fdf6e50f57aa6a391a4562 Signed-off-by: wuzhouhui <wuzhouhui@kingsoft.com> Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/453151 Tested-by: SPDK CI Jenkins <sys_sgci@intel.com> Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com> Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
40 lines
1.8 KiB
Markdown
40 lines
1.8 KiB
Markdown
# Notify library {#notify}
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The notify library implements an event bus, allowing users to register, generate,
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and listen for events. For example, the bdev library may register a new event type
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for bdev creation. Any time a bdev is created, it "sends" the event. Consumers of
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that event may periodically poll for new events to retrieve them.
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The event bus is implemented as a circular ring of fixed size. If event consumers
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do not poll frequently enough, events may be lost. All events are identified by a
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monotonically increasing integer, so missing events may be detected, although
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not recovered.
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# Register event types {#notify_register}
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During initialization the sender library should register its own event types using
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`spdk_notify_type_register(const char *type)`. Parameter 'type' is the name of
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notification type.
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# Get info about events {#notify_get_info}
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A consumer can get information about the available event types during runtime using
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`spdk_notify_foreach_type`, which iterates over registered notification types and
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calls a callback on each of them, so that user can produce detailed information
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about notification.
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# Get new events {#notify_listen}
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A consumer can get events by calling function `spdk_notify_foreach_event`.
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The caller should specify last received event and the maximum number of invocations.
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There might be multiple consumers of each event. The event bus is implemented as a
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circular buffer, so older events may be overwritten by newer ones.
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# Send events {#notify_send}
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When an event occurs, a library can invoke `spdk_notify_send` with two strings.
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One containing the type of the event, like "spdk_bdev_register", second with context,
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for example "Nvme0n1"
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# RPC Calls {#rpc_calls}
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See [JSON-RPC documentation](jsonrpc.md/#rpc_get_notification_types)
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