Re: [PATCH] Syslets - Fix cachemiss_thread return value

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, May 31, 2007 at 03:07:16PM -0700, Zach Brown wrote:
> Can you explain what motivated you to send out this patch?
> 
> It used to return 0.  It was changed because, unlike the syslet
> syscalls, sys_io_submit() doesn't have a simple 0 value to indicate
> success.  The current implementation wants to return the number of iocbs
> that were processed, including the one which blocked, from the cachemiss
> thread.  So before calling into an operation it sets task_ret_ret() so
> that the cachemiss thread can return it if it takes over.
> task_ret_reg() is holding a return value that is being returned by the
> cachemiss thread on behalf of a sys_io_submit() which blocked.
> 
> When I made the change I didn't really audit its effect on the other
> paths.  I suppose it's time to do that, and you could help by telling me
> if you saw something bad happen :).

The bad thing was sys_async_exec returning -NOSYS every time a new
cachemiss thread was created.

Without this patch, you'll see sys_async_exec failures with either of
the demos I sent out.  Dunno about the existing ones, but I bet they do
the same.

				Jeff

-- 
Work email - jdike at linux dot intel dot com
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux