lkml.org 
[lkml]   [2004]   [Feb]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC][PATCH] 2/6 POSIX message queues
Arnd wrote:

>Nothing difficult here, but slow and avoidable if you have the
>structures laid out properly.
>
I thought about using s32 for the kernel mq_attr structure, and didn't
like it: It would mean that 64-bit archs running native 64-bit apps must
do a conversion - glibc must expose a structure with long values.
Additionally, the posix message queue API uses 3 structures with long
values, and only one of them is new - we'll need wrappers anyway.
The actual values in the mq_attr structure would fit into s32:
- mq_flags is 0 or O_NONBLOCK
- mq_maxmsg is less than 32k (kmalloc'ed array of pointers)
- mq_msgsize is theoretically unlimited, but the current implementation
arbitrarily limits the value to 1 MB.

--
Manfred


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:01    [W:0.018 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site