[PATCH v2 1/2] ALSA: pcmtest: Add 'open' PCM callback error injection

[PATCH v2 1/2] ALSA: pcmtest: Add 'open' PCM callback error injection

[Ivan Orlov]

Extend 'pcmtest' virtual driver with 'open' callback error injection
functionality, as it already can inject errors into other PCM callbacks.
Add module parameter which enables EBUSY error injection in the 'open'
PCM callback.

Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
---
V1 -> V2:
- Split changes in the patch into two different patches

 sound/drivers/pcmtest.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/sound/drivers/pcmtest.c b/sound/drivers/pcmtest.c
index 291e7fe47893..e74c523e49eb 100644
--- a/sound/drivers/pcmtest.c
+++ b/sound/drivers/pcmtest.c
@@ -65,6 +65,7 @@ static int inject_delay;
 static bool inject_hwpars_err;
 static bool inject_prepare_err;
 static bool inject_trigger_err;
+static bool inject_open_err;
 
 static short fill_mode = FILL_MODE_PAT;
 
@@ -88,6 +89,9 @@ module_param(inject_prepare_err, bool, 0600);
 MODULE_PARM_DESC(inject_prepare_err, "Inject EINVAL error in the 'prepare' callback");
 module_param(inject_trigger_err, bool, 0600);
 MODULE_PARM_DESC(inject_trigger_err, "Inject EINVAL error in the 'trigger' callback");
+module_param(inject_open_err, bool, 0600);
+MODULE_PARM_DESC(inject_open_err, "Inject EBUSY error in the 'open' callback");
+
 
 struct pcmtst {
 	struct snd_pcm *pcm;
@@ -364,6 +368,9 @@ static int snd_pcmtst_pcm_open(struct snd_pcm_substream *substream)
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct pcmtst_buf_iter *v_iter;
 
+	if (inject_open_err)
+		return -EBUSY;
+
 	v_iter = kzalloc(sizeof(*v_iter), GFP_KERNEL);
 	if (!v_iter)
 		return -ENOMEM;
-- 
2.34.1

[PATCH v2 2/2] ALSA: pcmtest: minor optimizations

[Ivan Orlov]

Decrease the buffer filling overhead with conditional remainder
calculation in the 'inc_buf_pos' inline function.

Fix the driver to use already defined variables where it is possible
in 'check_buf_block_ni' and 'fill_block_pattern_n' functions.

Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
---
V1 -> V2:
- Split changes in the patch into two different patches

 sound/drivers/pcmtest.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/sound/drivers/pcmtest.c b/sound/drivers/pcmtest.c
index e74c523e49eb..08e14b5eb772 100644
--- a/sound/drivers/pcmtest.c
+++ b/sound/drivers/pcmtest.c
@@ -144,7 +144,8 @@ static inline void inc_buf_pos(struct pcmtst_buf_iter *v_iter, size_t by, size_t
 {
 	v_iter->total_bytes += by;
 	v_iter->buf_pos += by;
-	v_iter->buf_pos %= bytes;
+	if (v_iter->buf_pos >= bytes)
+		v_iter->buf_pos %= bytes;
 }
 
 /*
@@ -200,10 +201,10 @@ static void check_buf_block_ni(struct pcmtst_buf_iter *v_iter, struct snd_pcm_ru
 	u8 current_byte;
 
 	for (i = 0; i < v_iter->b_rw; i++) {
-		current_byte = runtime->dma_area[buf_pos_n(v_iter, channels, i % channels)];
+		ch_num = i % channels;
+		current_byte = runtime->dma_area[buf_pos_n(v_iter, channels, ch_num)];
 		if (!current_byte)
 			break;
-		ch_num = i % channels;
 		if (current_byte != patt_bufs[ch_num].buf[(v_iter->total_bytes / channels)
 							  % patt_bufs[ch_num].len]) {
 			v_iter->is_buf_corrupted = true;
@@ -243,7 +244,7 @@ static void fill_block_pattern_n(struct pcmtst_buf_iter *v_iter, struct snd_pcm_
 
 	for (i = 0; i < v_iter->b_rw; i++) {
 		ch_num = i % channels;
-		runtime->dma_area[buf_pos_n(v_iter, channels, i % channels)] =
+		runtime->dma_area[buf_pos_n(v_iter, channels, ch_num)] =
 			patt_bufs[ch_num].buf[(v_iter->total_bytes / channels)
 					      % patt_bufs[ch_num].len];
 		inc_buf_pos(v_iter, 1, runtime->dma_bytes);
-- 
2.34.1

Re: [PATCH v2 1/2] ALSA: pcmtest: Add 'open' PCM callback error injection

[Takashi Iwai]

On Thu, 13 Jul 2023 09:59:52 +0200,
Ivan Orlov wrote:
> 
> Extend 'pcmtest' virtual driver with 'open' callback error injection
> functionality, as it already can inject errors into other PCM callbacks.
> Add module parameter which enables EBUSY error injection in the 'open'
> PCM callback.
> 
> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
> ---
> V1 -> V2:
> - Split changes in the patch into two different patches

Applied both patches now.  Thanks.


Takashi