seq_lock.c 1.5 KB

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  1. /*
  2. * Do sleep inside a spin-lock
  3. * Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de>
  4. *
  5. *
  6. * This program is free software; you can redistribute it and/or modify
  7. * it under the terms of the GNU General Public License as published by
  8. * the Free Software Foundation; either version 2 of the License, or
  9. * (at your option) any later version.
  10. *
  11. * This program is distributed in the hope that it will be useful,
  12. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14. * GNU General Public License for more details.
  15. *
  16. * You should have received a copy of the GNU General Public License
  17. * along with this program; if not, write to the Free Software
  18. * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19. *
  20. */
  21. #include <linux/export.h>
  22. #include <sound/core.h>
  23. #include "seq_lock.h"
  24. #if defined(CONFIG_SMP) || defined(CONFIG_SND_DEBUG)
  25. /* wait until all locks are released */
  26. void snd_use_lock_sync_helper(snd_use_lock_t *lockp, const char *file, int line)
  27. {
  28. int max_count = 5 * HZ;
  29. if (atomic_read(lockp) < 0) {
  30. pr_warn("ALSA: seq_lock: lock trouble [counter = %d] in %s:%d\n", atomic_read(lockp), file, line);
  31. return;
  32. }
  33. while (atomic_read(lockp) > 0) {
  34. if (max_count == 0) {
  35. pr_warn("ALSA: seq_lock: timeout [%d left] in %s:%d\n", atomic_read(lockp), file, line);
  36. break;
  37. }
  38. schedule_timeout_uninterruptible(1);
  39. max_count--;
  40. }
  41. }
  42. EXPORT_SYMBOL(snd_use_lock_sync_helper);
  43. #endif