Re: [patch 00/13] Syslets, "Threadlets", generic AIO support, v3

On Wed, 28 Feb 2007, Chris Friesen wrote:

Davide Libenzi wrote:

struct async_syscall {
unsigned long nr_sysc;
unsigned long params[8];
long *result;
};

And what would async_wait() return bak? Pointers to "struct async_syscall"
or pointers to "result"?

Either one has downsides. Pointer to struct async_syscall requires that the
caller keep the struct around. Pointer to result requires that the caller
always reserve a location for the result.

Does the kernel care about the (possibly rare) case of callers that don't want
to pay attention to result? If so, what about adding some kind of
caller-specified handle to struct async_syscall, and having async_wait()
return the handle? In the case where the caller does care about the result,
the handle could just be the address of result.

Something like this (with async_wait() returning asynid's)?

struct async_syscall {
long *result;
unsigned long asynid;
unsigned long nr_sysc;
unsigned long params[8];
};



- Davide


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