Merge branch 'topic/pcm-locking' into for-next

here is a small series of patches for cleaning up / enhancing the
PCM core stuff.

5 files changed, 184 insertions, 186 deletions

diff --git a/sound/core/Makefile b/sound/core/Makefile
index 394a38909f6b..4daf2f58261c 100644
--- a/sound/core/Makefile
+++ b/sound/core/Makefile
@@ -14,6 +14,9 @@ snd-pcm-y := pcm.o pcm_native.o pcm_lib.o pcm_timer.o pcm_misc.o \
 		pcm_memory.o memalloc.o
 snd-pcm-$(CONFIG_SND_DMA_SGBUF) += sgbuf.o
 
+# for trace-points
+CFLAGS_pcm_lib.o := -I$(src)
+
 snd-pcm-dmaengine-objs := pcm_dmaengine.o
 
 snd-rawmidi-objs  := rawmidi.o
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index 31acc3df62cd..8f624b7af0ca 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -483,6 +483,19 @@ static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
 }
 
 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
+static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
+					 struct snd_info_buffer *buffer)
+{
+	struct snd_pcm_substream *substream = entry->private_data;
+	struct snd_pcm_runtime *runtime;
+
+	snd_pcm_stream_lock_irq(substream);
+	runtime = substream->runtime;
+	if (runtime && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
+		snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
+	snd_pcm_stream_unlock_irq(substream);
+}
+
 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
 				    struct snd_info_buffer *buffer)
 {
@@ -614,6 +627,22 @@ static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
 	}
 	substream->proc_status_entry = entry;
 
+#ifdef CONFIG_SND_PCM_XRUN_DEBUG
+	entry = snd_info_create_card_entry(card, "xrun_injection",
+					   substream->proc_root);
+	if (entry) {
+		entry->private_data = substream;
+		entry->c.text.read = NULL;
+		entry->c.text.write = snd_pcm_xrun_injection_write;
+		entry->mode = S_IFREG | S_IWUSR;
+		if (snd_info_register(entry) < 0) {
+			snd_info_free_entry(entry);
+			entry = NULL;
+		}
+	}
+	substream->proc_xrun_injection_entry = entry;
+#endif /* CONFIG_SND_PCM_XRUN_DEBUG */
+
 	return 0;
 }
 
@@ -627,6 +656,10 @@ static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
 	substream->proc_sw_params_entry = NULL;
 	snd_info_free_entry(substream->proc_status_entry);
 	substream->proc_status_entry = NULL;
+#ifdef CONFIG_SND_PCM_XRUN_DEBUG
+	snd_info_free_entry(substream->proc_xrun_injection_entry);
+	substream->proc_xrun_injection_entry = NULL;
+#endif
 	snd_info_free_entry(substream->proc_root);
 	substream->proc_root = NULL;
 	return 0;
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index dfc28542a007..ec9e7866177f 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -32,6 +32,15 @@
 #include <sound/pcm_params.h>
 #include <sound/timer.h>
 
+#ifdef CONFIG_SND_PCM_XRUN_DEBUG
+#define CREATE_TRACE_POINTS
+#include "pcm_trace.h"
+#else
+#define trace_hwptr(substream, pos, in_interrupt)
+#define trace_xrun(substream)
+#define trace_hw_ptr_error(substream, reason)
+#endif
+
 /*
  * fill ring buffer with silence
  * runtime->silence_start: starting pointer to silence area
@@ -146,10 +155,6 @@ EXPORT_SYMBOL(snd_pcm_debug_name);
 #define XRUN_DEBUG_BASIC	(1<<0)
 #define XRUN_DEBUG_STACK	(1<<1)	/* dump also stack */
 #define XRUN_DEBUG_JIFFIESCHECK	(1<<2)	/* do jiffies check */
-#define XRUN_DEBUG_PERIODUPDATE	(1<<3)	/* full period update info */
-#define XRUN_DEBUG_HWPTRUPDATE	(1<<4)	/* full hwptr update info */
-#define XRUN_DEBUG_LOG		(1<<5)	/* show last 10 positions on err */
-#define XRUN_DEBUG_LOGONCE	(1<<6)	/* do above only once */
 
 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 
@@ -168,6 +173,7 @@ static void xrun(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 
+	trace_xrun(substream);
 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
@@ -180,97 +186,19 @@ static void xrun(struct snd_pcm_substream *substream)
 }
 
 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
-#define hw_ptr_error(substream, fmt, args...)				\
+#define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)	\
 	do {								\
+		trace_hw_ptr_error(substream, reason);	\
 		if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {		\
-			xrun_log_show(substream);			\
-			pr_err_ratelimited("ALSA: PCM: " fmt, ##args);	\
+			pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
+					   (in_interrupt) ? 'Q' : 'P', ##args);	\
 			dump_stack_on_xrun(substream);			\
 		}							\
 	} while (0)
 
-#define XRUN_LOG_CNT	10
-
-struct hwptr_log_entry {
-	unsigned int in_interrupt;
-	unsigned long jiffies;
-	snd_pcm_uframes_t pos;
-	snd_pcm_uframes_t period_size;
-	snd_pcm_uframes_t buffer_size;
-	snd_pcm_uframes_t old_hw_ptr;
-	snd_pcm_uframes_t hw_ptr_base;
-};
-
-struct snd_pcm_hwptr_log {
-	unsigned int idx;
-	unsigned int hit: 1;
-	struct hwptr_log_entry entries[XRUN_LOG_CNT];
-};
-
-static void xrun_log(struct snd_pcm_substream *substream,
-		     snd_pcm_uframes_t pos, int in_interrupt)
-{
-	struct snd_pcm_runtime *runtime = substream->runtime;
-	struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
-	struct hwptr_log_entry *entry;
-
-	if (log == NULL) {
-		log = kzalloc(sizeof(*log), GFP_ATOMIC);
-		if (log == NULL)
-			return;
-		runtime->hwptr_log = log;
-	} else {
-		if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
-			return;
-	}
-	entry = &log->entries[log->idx];
-	entry->in_interrupt = in_interrupt;
-	entry->jiffies = jiffies;
-	entry->pos = pos;
-	entry->period_size = runtime->period_size;
-	entry->buffer_size = runtime->buffer_size;
-	entry->old_hw_ptr = runtime->status->hw_ptr;
-	entry->hw_ptr_base = runtime->hw_ptr_base;
-	log->idx = (log->idx + 1) % XRUN_LOG_CNT;
-}
-
-static void xrun_log_show(struct snd_pcm_substream *substream)
-{
-	struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
-	struct hwptr_log_entry *entry;
-	char name[16];
-	unsigned int idx;
-	int cnt;
-
-	if (log == NULL)
-		return;
-	if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
-		return;
-	snd_pcm_debug_name(substream, name, sizeof(name));
-	for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
-		entry = &log->entries[idx];
-		if (entry->period_size == 0)
-			break;
-		pr_info("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
-			   "hwptr=%ld/%ld\n",
-			   name, entry->in_interrupt ? "[Q] " : "",
-			   entry->jiffies,
-			   (unsigned long)entry->pos,
-			   (unsigned long)entry->period_size,
-			   (unsigned long)entry->buffer_size,
-			   (unsigned long)entry->old_hw_ptr,
-			   (unsigned long)entry->hw_ptr_base);
-		idx++;
-		idx %= XRUN_LOG_CNT;
-	}
-	log->hit = 1;
-}
-
 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 
 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
-#define xrun_log(substream, pos, in_interrupt)	do { } while (0)
-#define xrun_log_show(substream)	do { } while (0)
 
 #endif
 
@@ -343,17 +271,15 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 		if (printk_ratelimit()) {
 			char name[16];
 			snd_pcm_debug_name(substream, name, sizeof(name));
-			xrun_log_show(substream);
 			pcm_err(substream->pcm,
-				"XRUN: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
+				"BUG: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
 				name, pos, runtime->buffer_size,
 				runtime->period_size);
 		}
 		pos = 0;
 	}
 	pos -= pos % runtime->min_align;
-	if (xrun_debug(substream, XRUN_DEBUG_LOG))
-		xrun_log(substream, pos, in_interrupt);
+	trace_hwptr(substream, pos, in_interrupt);
 	hw_base = runtime->hw_ptr_base;
 	new_hw_ptr = hw_base + pos;
 	if (in_interrupt) {
@@ -388,22 +314,6 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 	delta = new_hw_ptr - old_hw_ptr;
 	if (delta < 0)
 		delta += runtime->boundary;
-	if (xrun_debug(substream, in_interrupt ?
-			XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
-		char name[16];
-		snd_pcm_debug_name(substream, name, sizeof(name));
-		pcm_dbg(substream->pcm,
-			"%s_update: %s: pos=%u/%u/%u, hwptr=%ld/%ld/%ld/%ld\n",
-			   in_interrupt ? "period" : "hwptr",
-			   name,
-			   (unsigned int)pos,
-			   (unsigned int)runtime->period_size,
-			   (unsigned int)runtime->buffer_size,
-			   (unsigned long)delta,
-			   (unsigned long)old_hw_ptr,
-			   (unsigned long)new_hw_ptr,
-			   (unsigned long)runtime->hw_ptr_base);
-	}
 
 	if (runtime->no_period_wakeup) {
 		snd_pcm_sframes_t xrun_threshold;
@@ -431,13 +341,10 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 
 	/* something must be really wrong */
 	if (delta >= runtime->buffer_size + runtime->period_size) {
-		hw_ptr_error(substream,
-			       "Unexpected hw_pointer value %s"
-			       "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
-			       "old_hw_ptr=%ld)\n",
-				     in_interrupt ? "[Q] " : "[P]",
-				     substream->stream, (long)pos,
-				     (long)new_hw_ptr, (long)old_hw_ptr);
+		hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
+			     "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
+			     substream->stream, (long)pos,
+			     (long)new_hw_ptr, (long)old_hw_ptr);
 		return 0;
 	}
 
@@ -474,11 +381,8 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 			delta--;
 		}
 		/* align hw_base to buffer_size */
-		hw_ptr_error(substream,
-			     "hw_ptr skipping! %s"
-			     "(pos=%ld, delta=%ld, period=%ld, "
-			     "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
-			     in_interrupt ? "[Q] " : "",
+		hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
+			     "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 			     (long)pos, (long)hdelta,
 			     (long)runtime->period_size, jdelta,
 			     ((hdelta * HZ) / runtime->rate), hw_base,
@@ -490,11 +394,9 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 	}
  no_jiffies_check:
 	if (delta > runtime->period_size + runtime->period_size / 2) {
-		hw_ptr_error(substream,
-			     "Lost interrupts? %s"
-			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
-			     "old_hw_ptr=%ld)\n",
-			     in_interrupt ? "[Q] " : "",
+		hw_ptr_error(substream, in_interrupt,
+			     "Lost interrupts?",
+			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 			     substream->stream, (long)delta,
 			     (long)new_hw_ptr,
 			     (long)old_hw_ptr);
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 4d5795d8b9f7..ca224fa2a33a 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -900,14 +900,19 @@ static int snd_pcm_action_single(struct action_ops *ops,
 	return res;
 }
 
-/* call in mutex-protected context */
-static int snd_pcm_action_mutex(struct action_ops *ops,
-				struct snd_pcm_substream *substream,
-				int state)
+/*
+ *  Note: call with stream lock
+ */
+static int snd_pcm_action(struct action_ops *ops,
+			  struct snd_pcm_substream *substream,
+			  int state)
 {
 	int res;
 
-	if (snd_pcm_stream_linked(substream)) {
+	if (!snd_pcm_stream_linked(substream))
+		return snd_pcm_action_single(ops, substream, state);
+
+	if (substream->pcm->nonatomic) {
 		if (!mutex_trylock(&substream->group->mutex)) {
 			mutex_unlock(&substream->self_group.mutex);
 			mutex_lock(&substream->group->mutex);
@@ -916,24 +921,6 @@ static int snd_pcm_action_mutex(struct action_ops *ops,
 		res = snd_pcm_action_group(ops, substream, state, 1);
 		mutex_unlock(&substream->group->mutex);
 	} else {
-		res = snd_pcm_action_single(ops, substream, state);
-	}
-	return res;
-}
-
-/*
- *  Note: call with stream lock
- */
-static int snd_pcm_action(struct action_ops *ops,
-			  struct snd_pcm_substream *substream,
-			  int state)
-{
-	int res;
-
-	if (substream->pcm->nonatomic)
-		return snd_pcm_action_mutex(ops, substream, state);
-
-	if (snd_pcm_stream_linked(substream)) {
 		if (!spin_trylock(&substream->group->lock)) {
 			spin_unlock(&substream->self_group.lock);
 			spin_lock(&substream->group->lock);
@@ -941,34 +928,10 @@ static int snd_pcm_action(struct action_ops *ops,
 		}
 		res = snd_pcm_action_group(ops, substream, state, 1);
 		spin_unlock(&substream->group->lock);
-	} else {
-		res = snd_pcm_action_single(ops, substream, state);
 	}
 	return res;
 }
 
-static int snd_pcm_action_lock_mutex(struct action_ops *ops,
-				     struct snd_pcm_substream *substream,
-				     int state)
-{
-	int res;
-
-	down_read(&snd_pcm_link_rwsem);
-	if (snd_pcm_stream_linked(substream)) {
-		mutex_lock(&substream->group->mutex);
-		mutex_lock(&substream->self_group.mutex);
-		res = snd_pcm_action_group(ops, substream, state, 1);
-		mutex_unlock(&substream->self_group.mutex);
-		mutex_unlock(&substream->group->mutex);
-	} else {
-		mutex_lock(&substream->self_group.mutex);
-		res = snd_pcm_action_single(ops, substream, state);
-		mutex_unlock(&substream->self_group.mutex);
-	}
-	up_read(&snd_pcm_link_rwsem);
-	return res;
-}
-
 /*
  *  Note: don't use any locks before
  */
@@ -978,22 +941,9 @@ static int snd_pcm_action_lock_irq(struct action_ops *ops,
 {
 	int res;
 
-	if (substream->pcm->nonatomic)
-		return snd_pcm_action_lock_mutex(ops, substream, state);
-
-	read_lock_irq(&snd_pcm_link_rwlock);
-	if (snd_pcm_stream_linked(substream)) {
-		spin_lock(&substream->group->lock);
-		spin_lock(&substream->self_group.lock);
-		res = snd_pcm_action_group(ops, substream, state, 1);
-		spin_unlock(&substream->self_group.lock);
-		spin_unlock(&substream->group->lock);
-	} else {
-		spin_lock(&substream->self_group.lock);
-		res = snd_pcm_action_single(ops, substream, state);
-		spin_unlock(&substream->self_group.lock);
-	}
-	read_unlock_irq(&snd_pcm_link_rwlock);
+	snd_pcm_stream_lock_irq(substream);
+	res = snd_pcm_action(ops, substream, state);
+	snd_pcm_stream_unlock_irq(substream);
 	return res;
 }
 
diff --git a/sound/core/pcm_trace.h b/sound/core/pcm_trace.h
new file mode 100644
index 000000000000..b63b654da5ff
--- /dev/null
+++ b/sound/core/pcm_trace.h
@@ -0,0 +1,110 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM snd_pcm
+#define TRACE_INCLUDE_FILE pcm_trace
+
+#if !defined(_PCM_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _PCM_TRACE_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(hwptr,
+	TP_PROTO(struct snd_pcm_substream *substream, snd_pcm_uframes_t pos, bool irq),
+	TP_ARGS(substream, pos, irq),
+	TP_STRUCT__entry(
+		__field( bool, in_interrupt )
+		__field( unsigned int, card )
+		__field( unsigned int, device )
+		__field( unsigned int, number )
+		__field( unsigned int, stream )
+		__field( snd_pcm_uframes_t, pos )
+		__field( snd_pcm_uframes_t, period_size )
+		__field( snd_pcm_uframes_t, buffer_size )
+		__field( snd_pcm_uframes_t, old_hw_ptr )
+		__field( snd_pcm_uframes_t, hw_ptr_base )
+	),
+	TP_fast_assign(
+		__entry->in_interrupt = (irq);
+		__entry->card = (substream)->pcm->card->number;
+		__entry->device = (substream)->pcm->device;
+		__entry->number = (substream)->number;
+		__entry->stream = (substream)->stream;
+		__entry->pos = (pos);
+		__entry->period_size = (substream)->runtime->period_size;
+		__entry->buffer_size = (substream)->runtime->buffer_size;
+		__entry->old_hw_ptr = (substream)->runtime->status->hw_ptr;
+		__entry->hw_ptr_base = (substream)->runtime->hw_ptr_base;
+	),
+	TP_printk("pcmC%dD%d%c/sub%d: %s: pos=%lu, old=%lu, base=%lu, period=%lu, buf=%lu",
+		  __entry->card, __entry->device,
+		  __entry->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c',
+		  __entry->number,
+		  __entry->in_interrupt ? "IRQ" : "POS",
+		  (unsigned long)__entry->pos,
+		  (unsigned long)__entry->old_hw_ptr,
+		  (unsigned long)__entry->hw_ptr_base,
+		  (unsigned long)__entry->period_size,
+		  (unsigned long)__entry->buffer_size)
+);
+
+TRACE_EVENT(xrun,
+	TP_PROTO(struct snd_pcm_substream *substream),
+	TP_ARGS(substream),
+	TP_STRUCT__entry(
+		__field( unsigned int, card )
+		__field( unsigned int, device )
+		__field( unsigned int, number )
+		__field( unsigned int, stream )
+		__field( snd_pcm_uframes_t, period_size )
+		__field( snd_pcm_uframes_t, buffer_size )
+		__field( snd_pcm_uframes_t, old_hw_ptr )
+		__field( snd_pcm_uframes_t, hw_ptr_base )
+	),
+	TP_fast_assign(
+		__entry->card = (substream)->pcm->card->number;
+		__entry->device = (substream)->pcm->device;
+		__entry->number = (substream)->number;
+		__entry->stream = (substream)->stream;
+		__entry->period_size = (substream)->runtime->period_size;
+		__entry->buffer_size = (substream)->runtime->buffer_size;
+		__entry->old_hw_ptr = (substream)->runtime->status->hw_ptr;
+		__entry->hw_ptr_base = (substream)->runtime->hw_ptr_base;
+	),
+	TP_printk("pcmC%dD%d%c/sub%d: XRUN: old=%lu, base=%lu, period=%lu, buf=%lu",
+		  __entry->card, __entry->device,
+		  __entry->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c',
+		  __entry->number,
+		  (unsigned long)__entry->old_hw_ptr,
+		  (unsigned long)__entry->hw_ptr_base,
+		  (unsigned long)__entry->period_size,
+		  (unsigned long)__entry->buffer_size)
+);
+
+TRACE_EVENT(hw_ptr_error,
+	TP_PROTO(struct snd_pcm_substream *substream, const char *why),
+	TP_ARGS(substream, why),
+	TP_STRUCT__entry(
+		__field( unsigned int, card )
+		__field( unsigned int, device )
+		__field( unsigned int, number )
+		__field( unsigned int, stream )
+		__field( const char *, reason )
+	),
+	TP_fast_assign(
+		__entry->card = (substream)->pcm->card->number;
+		__entry->device = (substream)->pcm->device;
+		__entry->number = (substream)->number;
+		__entry->stream = (substream)->stream;
+		__entry->reason = (why);
+	),
+	TP_printk("pcmC%dD%d%c/sub%d: ERROR: %s",
+		  __entry->card, __entry->device,
+		  __entry->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c',
+		  __entry->number, __entry->reason)
+);
+
+#endif /* _PCM_TRACE_H */
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#include <trace/define_trace.h>