rockbox/firmware/include/buflib_malloc.h
Aidan MacDonald 800bc000a0 buflib: Add pinned get/put data functions
These are more efficient than separate pin/unpin calls because
pin count increment and decrement can be done cheaply when the
data pointer is known.

Secondly, pinned access can be made safe against preemption by
hardware interrupts or other CPU cores; buflib_get_data() can't.
This makes it more useful under different threading models and
for SMP targets; both of which are not particularly relevant to
Rockbox now, but might be in the future.

Change-Id: I09284251b83bbbc59ef88a494c8fda26a7f7ef26
2023-01-15 11:06:27 +00:00

65 lines
1.9 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2023 Aidan MacDonald
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef _BUFLIB_MALLOC_H_
#define _BUFLIB_MALLOC_H_
#ifndef _BUFLIB_H_
# error "include buflib.h instead"
#endif
struct buflib_malloc_handle
{
void *data;
void *user;
size_t size;
unsigned int pin_count;
struct buflib_callbacks *ops;
};
struct buflib_context
{
struct buflib_malloc_handle *allocs;
size_t num_allocs;
void *buf;
size_t bufsize;
};
#ifndef BUFLIB_DEBUG_GET_DATA
static inline void *buflib_get_data(struct buflib_context *ctx, int handle)
{
return ctx->allocs[handle - 1].user;
}
#endif
static inline void *buflib_get_data_pinned(struct buflib_context *ctx, int handle)
{
buflib_pin(ctx, handle);
return buflib_get_data(ctx, handle);
}
void _buflib_malloc_put_data_pinned(struct buflib_context *ctx, void *data);
static inline void buflib_put_data_pinned(struct buflib_context *ctx, void *data)
{
_buflib_malloc_put_data_pinned(ctx, data);
}
#endif /* _BUFLIB_MALLOC_H_ */