Fix comment about what we do when there are no listeners.
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svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=109505
@ -381,19 +381,9 @@ devpoll(dev_t dev, int events, d_thread_t *td)
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* Common routine that tries to make sending messages as easy as possible.
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* We allocate memory for the data, copy strings into that, but do not
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* free it unless there's an error. The dequeue part of the driver should
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* free the data. We do not send any data if there is no listeners on the
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* /dev/devctl device. We assume that on startup, any program that wishes
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* to do things based on devices that have attached before it starts will
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* query the tree to find out its current state. This decision may
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* be revisited if there are difficulties determining if one should do an
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* action or not (eg, are all actions that the listening program idempotent
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* or not). This may also open up races as well (say if the listener
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* dies just before a device goes away, and is run again just after, no
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* detach action would happen). The flip side would be that we'd need to
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* limit the size of the queue because otherwise if no listener is running
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* then we'd have unbounded growth. Most systems have less than 100 (maybe
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* even less than 50) devices, so maybe a limit of 200 or 300 wouldn't be
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* too horrible. XXX
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* free the data. We don't send data when the device is disabled. We do
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* send data, even when we have no listeners, because we wish to avoid
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* races relating to startup and restart of listening applications.
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*/
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static void
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devaddq(const char *type, const char *what, device_t dev)
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