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From: Stefan Kisdaroczi <kisda@domain.hid>
To: xenomai@xenomai.org
Subject: [Xenomai-core] rt_heap in userspace, heapsize
Date: Tue, 17 Jan 2006 14:57:22 +0100	[thread overview]
Message-ID: <43CCF7C2.6070403@domain.hid> (raw)

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Hi,

I made a small test with rt_heap_ in userspace,
i think I understood the actual limitations of the userspace support.
I used 10000 as heapsize. Xenomai 2.1-RC2/x86.

This should alloc the entire heap, according to the API documentation:
rt_heap_create( ..., ..., 10000, ... )
rt_heap_alloc( ..., 10000, ..., .... ) -> This call fails, but it should work

Using heapsize 0 it works:
rt_heap_create( ..., ..., 10000, ... )
rt_heap_alloc( ..., 0, ..., .... )

rt_heap_inquire shows a heapsize of 12228 (IIRC).
So, this would probably work (untested):
rt_heap_create( ..., ..., 10000, ... )
rt_heap_alloc( ..., 12228, ..., .... )

The 2228 bytes difference seems to be the space needed for the heap control structures.

I think the following should be fixed:
1) rt_create_alloc should alter the heapsize the same as rt_heap_create does
2) rt_heap_inquire should return the _real_ heapsize

thx
kisda



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             reply	other threads:[~2006-01-17 13:57 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-01-17 13:57 Stefan Kisdaroczi [this message]
2006-01-17 21:37 ` [Xenomai-core] rt_heap in userspace, heapsize [patch] Stefan Kisdaroczi
2006-01-31 18:17   ` Philippe Gerum

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