diff options
Diffstat (limited to 'sound/core/seq/seq_lock.c')
-rw-r--r-- | sound/core/seq/seq_lock.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/sound/core/seq/seq_lock.c b/sound/core/seq/seq_lock.c new file mode 100644 index 000000000..3b693e924 --- /dev/null +++ b/sound/core/seq/seq_lock.c @@ -0,0 +1,49 @@ +/* + * Do sleep inside a spin-lock + * Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de> + * + * + * 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/export.h> +#include <sound/core.h> +#include "seq_lock.h" + +#if defined(CONFIG_SMP) || defined(CONFIG_SND_DEBUG) + +/* wait until all locks are released */ +void snd_use_lock_sync_helper(snd_use_lock_t *lockp, const char *file, int line) +{ + int max_count = 5 * HZ; + + if (atomic_read(lockp) < 0) { + pr_warn("ALSA: seq_lock: lock trouble [counter = %d] in %s:%d\n", atomic_read(lockp), file, line); + return; + } + while (atomic_read(lockp) > 0) { + if (max_count == 0) { + pr_warn("ALSA: seq_lock: timeout [%d left] in %s:%d\n", atomic_read(lockp), file, line); + break; + } + schedule_timeout_uninterruptible(1); + max_count--; + } +} + +EXPORT_SYMBOL(snd_use_lock_sync_helper); + +#endif |