Messages in this thread |  | | Date | Tue, 22 Aug 2000 20:03:29 +0200 (MET DST) | From | Roman Zippel <> | Subject | Re: [PATCH] Re: Move of input drivers, some word needed from you |
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Hi,
> Now, currently, most of the recieve handling is postponed to the > bottom half. I question the usefulness of this optimization. It > certainly adds latency. What is it that needs to be done on reception > of a few chars? Copy the data to userspace, and hit the waitq of the > process that's waiting for data. If you want to prevent the races, use > a kernel-space circular buffer, and do the processing (copy to > userspace) in the context of the wokenup process.
The input line handling in n_tty.c should IMO not be done on interrupt level. AFAIK it's the only reason put_char can't sleep and you can get the input line handling with a simple (but admittingly not very realistic) example to overflow, because it has to echo chars back and at some point it simply has to drop characters.
bye, Roman
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