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Date: Tue, 6 Feb 2007 15:23:47 -0800 (PST)
From: Davide Libenzi <davidel@xmailserver.org>
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To: Kent Overstreet <kent.overstreet@gmail.com>
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Subject: Re: [PATCH 2 of 4] Introduce i386 fibril scheduling
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On Tue, 6 Feb 2007, Kent Overstreet wrote:

> The trouble with differentiating between calls that block and calls
> that don't is you completely loose the ability to batch syscalls
> together; this is potentially a major win of an asynchronous
> interface.

It doesn't necessarly have to, once you extend the single return code to a 
vector:

struct async_submit {
	void *cookie;
	int sysc_nbr;
	int nargs;
	long args[ASYNC_MAX_ARGS];
	int async_result;
};

int async_submit(struct async_submit *a, int n);

And async_submit() can mark each one ->async_result with -EASYNC (syscall 
has been batched), or another code (syscall completed w/out schedule).
IMO, once you get a -EASYNC for a syscall, you *have* to retire the result.



- Davide