Handles are allocated at the end, growing downwards.
The tiny allocations from r30478 broke buflib, since it was assumed that the only shrinkable allocation (the audiobuffer) is the very last allocation.
The tiny allocations however fit into the reserve buffer for new handles, breaking the above assumption, and they can't shrink to make room for handles.
Now, move any allocations before audiobuf (or shrink audiobuf like before) to make room for handles. This also unifies some duplicated code.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30486 a1c6a512-1295-4272-9138-f99709370657
* Enhance allocation function comments to better state the return value and what an invalid value is
* Change clients to check for "< 0" instead of "<= 0" or "== 0"
* Return -1 or -2 depending on the exact failure in buflib_alloc_ex.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30469 a1c6a512-1295-4272-9138-f99709370657
This enables the ability to allocate (and free) memory dynamically
without fragmentation, through compaction. This means allocations can move
and fragmentation be reduced. Most changes are preparing Rockbox for this,
which many times means adding a move callback which can temporarily disable
movement when the corresponding code is in a critical section.
For now, the audio buffer allocation has a central role, because it's the one
having allocated most. This buffer is able to shrink itself, for which it
needs to stop playback for a very short moment. For this,
audio_buffer_available() returns the size of the audio buffer which can
possibly be used by other allocations because the audio buffer can shrink.
lastfm scrobbling and timestretch can now be toggled at runtime without
requiring a reboot.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30381 a1c6a512-1295-4272-9138-f99709370657
The buflib memory allocator is handle based and can free and
compact, move or resize memory on demand. This allows to effeciently
allocate memory dynamically without an MMU, by avoiding fragmentation
through memory compaction.
This patch adds the buflib library to the core, along with
convinience wrappers to omit the context parameter. Compaction is
not yet enabled, but will be in a later patch. Therefore, this acts as a
replacement for buffer_alloc/buffer_get_buffer() with the benifit of a debug
menu.
See buflib.h for some API documentation.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30380 a1c6a512-1295-4272-9138-f99709370657
