linux/sound/core/seq/seq_prioq.c
Takashi Iwai 24db8bbaa3 ALSA: seq: Drop superfluous error/debug messages after malloc failures
The kernel memory allocators already report the errors when the
requested allocation fails, thus we don't need to warn it again in
each caller side.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-03-10 15:41:18 +01:00

452 lines
11 KiB
C

/*
* ALSA sequencer Priority Queue
* Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
*
*
* 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 program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/time.h>
#include <linux/slab.h>
#include <sound/core.h>
#include "seq_timer.h"
#include "seq_prioq.h"
/* Implementation is a simple linked list for now...
This priority queue orders the events on timestamp. For events with an
equeal timestamp the queue behaves as a FIFO.
*
* +-------+
* Head --> | first |
* +-------+
* |next
* +-----v-+
* | |
* +-------+
* |
* +-----v-+
* | |
* +-------+
* |
* +-----v-+
* Tail --> | last |
* +-------+
*
*/
/* create new prioq (constructor) */
struct snd_seq_prioq *snd_seq_prioq_new(void)
{
struct snd_seq_prioq *f;
f = kzalloc(sizeof(*f), GFP_KERNEL);
if (!f)
return NULL;
spin_lock_init(&f->lock);
f->head = NULL;
f->tail = NULL;
f->cells = 0;
return f;
}
/* delete prioq (destructor) */
void snd_seq_prioq_delete(struct snd_seq_prioq **fifo)
{
struct snd_seq_prioq *f = *fifo;
*fifo = NULL;
if (f == NULL) {
pr_debug("ALSA: seq: snd_seq_prioq_delete() called with NULL prioq\n");
return;
}
/* release resources...*/
/*....................*/
if (f->cells > 0) {
/* drain prioQ */
while (f->cells > 0)
snd_seq_cell_free(snd_seq_prioq_cell_out(f));
}
kfree(f);
}
/* compare timestamp between events */
/* return 1 if a >= b; 0 */
static inline int compare_timestamp(struct snd_seq_event *a,
struct snd_seq_event *b)
{
if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
/* compare ticks */
return (snd_seq_compare_tick_time(&a->time.tick, &b->time.tick));
} else {
/* compare real time */
return (snd_seq_compare_real_time(&a->time.time, &b->time.time));
}
}
/* compare timestamp between events */
/* return negative if a < b;
* zero if a = b;
* positive if a > b;
*/
static inline int compare_timestamp_rel(struct snd_seq_event *a,
struct snd_seq_event *b)
{
if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
/* compare ticks */
if (a->time.tick > b->time.tick)
return 1;
else if (a->time.tick == b->time.tick)
return 0;
else
return -1;
} else {
/* compare real time */
if (a->time.time.tv_sec > b->time.time.tv_sec)
return 1;
else if (a->time.time.tv_sec == b->time.time.tv_sec) {
if (a->time.time.tv_nsec > b->time.time.tv_nsec)
return 1;
else if (a->time.time.tv_nsec == b->time.time.tv_nsec)
return 0;
else
return -1;
} else
return -1;
}
}
/* enqueue cell to prioq */
int snd_seq_prioq_cell_in(struct snd_seq_prioq * f,
struct snd_seq_event_cell * cell)
{
struct snd_seq_event_cell *cur, *prev;
unsigned long flags;
int count;
int prior;
if (snd_BUG_ON(!f || !cell))
return -EINVAL;
/* check flags */
prior = (cell->event.flags & SNDRV_SEQ_PRIORITY_MASK);
spin_lock_irqsave(&f->lock, flags);
/* check if this element needs to inserted at the end (ie. ordered
data is inserted) This will be very likeley if a sequencer
application or midi file player is feeding us (sequential) data */
if (f->tail && !prior) {
if (compare_timestamp(&cell->event, &f->tail->event)) {
/* add new cell to tail of the fifo */
f->tail->next = cell;
f->tail = cell;
cell->next = NULL;
f->cells++;
spin_unlock_irqrestore(&f->lock, flags);
return 0;
}
}
/* traverse list of elements to find the place where the new cell is
to be inserted... Note that this is a order n process ! */
prev = NULL; /* previous cell */
cur = f->head; /* cursor */
count = 10000; /* FIXME: enough big, isn't it? */
while (cur != NULL) {
/* compare timestamps */
int rel = compare_timestamp_rel(&cell->event, &cur->event);
if (rel < 0)
/* new cell has earlier schedule time, */
break;
else if (rel == 0 && prior)
/* equal schedule time and prior to others */
break;
/* new cell has equal or larger schedule time, */
/* move cursor to next cell */
prev = cur;
cur = cur->next;
if (! --count) {
spin_unlock_irqrestore(&f->lock, flags);
pr_err("ALSA: seq: cannot find a pointer.. infinite loop?\n");
return -EINVAL;
}
}
/* insert it before cursor */
if (prev != NULL)
prev->next = cell;
cell->next = cur;
if (f->head == cur) /* this is the first cell, set head to it */
f->head = cell;
if (cur == NULL) /* reached end of the list */
f->tail = cell;
f->cells++;
spin_unlock_irqrestore(&f->lock, flags);
return 0;
}
/* dequeue cell from prioq */
struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f)
{
struct snd_seq_event_cell *cell;
unsigned long flags;
if (f == NULL) {
pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
return NULL;
}
spin_lock_irqsave(&f->lock, flags);
cell = f->head;
if (cell) {
f->head = cell->next;
/* reset tail if this was the last element */
if (f->tail == cell)
f->tail = NULL;
cell->next = NULL;
f->cells--;
}
spin_unlock_irqrestore(&f->lock, flags);
return cell;
}
/* return number of events available in prioq */
int snd_seq_prioq_avail(struct snd_seq_prioq * f)
{
if (f == NULL) {
pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
return 0;
}
return f->cells;
}
/* peek at cell at the head of the prioq */
struct snd_seq_event_cell *snd_seq_prioq_cell_peek(struct snd_seq_prioq * f)
{
if (f == NULL) {
pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
return NULL;
}
return f->head;
}
static inline int prioq_match(struct snd_seq_event_cell *cell,
int client, int timestamp)
{
if (cell->event.source.client == client ||
cell->event.dest.client == client)
return 1;
if (!timestamp)
return 0;
switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
case SNDRV_SEQ_TIME_STAMP_TICK:
if (cell->event.time.tick)
return 1;
break;
case SNDRV_SEQ_TIME_STAMP_REAL:
if (cell->event.time.time.tv_sec ||
cell->event.time.time.tv_nsec)
return 1;
break;
}
return 0;
}
/* remove cells for left client */
void snd_seq_prioq_leave(struct snd_seq_prioq * f, int client, int timestamp)
{
register struct snd_seq_event_cell *cell, *next;
unsigned long flags;
struct snd_seq_event_cell *prev = NULL;
struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
/* collect all removed cells */
spin_lock_irqsave(&f->lock, flags);
cell = f->head;
while (cell) {
next = cell->next;
if (prioq_match(cell, client, timestamp)) {
/* remove cell from prioq */
if (cell == f->head) {
f->head = cell->next;
} else {
prev->next = cell->next;
}
if (cell == f->tail)
f->tail = cell->next;
f->cells--;
/* add cell to free list */
cell->next = NULL;
if (freefirst == NULL) {
freefirst = cell;
} else {
freeprev->next = cell;
}
freeprev = cell;
} else {
#if 0
pr_debug("ALSA: seq: type = %i, source = %i, dest = %i, "
"client = %i\n",
cell->event.type,
cell->event.source.client,
cell->event.dest.client,
client);
#endif
prev = cell;
}
cell = next;
}
spin_unlock_irqrestore(&f->lock, flags);
/* remove selected cells */
while (freefirst) {
freenext = freefirst->next;
snd_seq_cell_free(freefirst);
freefirst = freenext;
}
}
static int prioq_remove_match(struct snd_seq_remove_events *info,
struct snd_seq_event *ev)
{
int res;
if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) {
if (ev->dest.client != info->dest.client ||
ev->dest.port != info->dest.port)
return 0;
}
if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST_CHANNEL) {
if (! snd_seq_ev_is_channel_type(ev))
return 0;
/* data.note.channel and data.control.channel are identical */
if (ev->data.note.channel != info->channel)
return 0;
}
if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_AFTER) {
if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
else
res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
if (!res)
return 0;
}
if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_BEFORE) {
if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
else
res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
if (res)
return 0;
}
if (info->remove_mode & SNDRV_SEQ_REMOVE_EVENT_TYPE) {
if (ev->type != info->type)
return 0;
}
if (info->remove_mode & SNDRV_SEQ_REMOVE_IGNORE_OFF) {
/* Do not remove off events */
switch (ev->type) {
case SNDRV_SEQ_EVENT_NOTEOFF:
/* case SNDRV_SEQ_EVENT_SAMPLE_STOP: */
return 0;
default:
break;
}
}
if (info->remove_mode & SNDRV_SEQ_REMOVE_TAG_MATCH) {
if (info->tag != ev->tag)
return 0;
}
return 1;
}
/* remove cells matching remove criteria */
void snd_seq_prioq_remove_events(struct snd_seq_prioq * f, int client,
struct snd_seq_remove_events *info)
{
struct snd_seq_event_cell *cell, *next;
unsigned long flags;
struct snd_seq_event_cell *prev = NULL;
struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
/* collect all removed cells */
spin_lock_irqsave(&f->lock, flags);
cell = f->head;
while (cell) {
next = cell->next;
if (cell->event.source.client == client &&
prioq_remove_match(info, &cell->event)) {
/* remove cell from prioq */
if (cell == f->head) {
f->head = cell->next;
} else {
prev->next = cell->next;
}
if (cell == f->tail)
f->tail = cell->next;
f->cells--;
/* add cell to free list */
cell->next = NULL;
if (freefirst == NULL) {
freefirst = cell;
} else {
freeprev->next = cell;
}
freeprev = cell;
} else {
prev = cell;
}
cell = next;
}
spin_unlock_irqrestore(&f->lock, flags);
/* remove selected cells */
while (freefirst) {
freenext = freefirst->next;
snd_seq_cell_free(freefirst);
freefirst = freenext;
}
}