[alsa-devel] [PATCH 12/13] ASoC: rsnd: fixup not to call clk_get/set under non-atomic
Kuninori Morimoto
kuninori.morimoto.gx at renesas.com
Mon Sep 3 09:08:58 CEST 2018
From: Jiada Wang <jiada_wang at mentor.com>
Clocking operations clk_get/set_rate, are non-atomic,
they shouldn't be called in soc_pcm_trigger() which is atomic.
Following issue was found due to execution of clk_get_rate() causes
sleep in soc_pcm_trigger(), which shouldn't be blocked.
We can reproduce this issue by following
> enable CONFIG_DEBUG_ATOMIC_SLEEP=y
> compile, and boot
> mount -t debugfs none /sys/kernel/debug
> while true; do cat /sys/kernel/debug/clk/clk_summary > /dev/null; done &
> while true; do aplay xxx; done
This patch adds support to .prepare callback, and moves non-atomic
clocking operations to it. As .prepare is non-atomic, it is always
called before trigger_start/trigger_stop.
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620
in_atomic(): 1, irqs_disabled(): 128, pid: 2242, name: aplay
INFO: lockdep is turned off.
irq event stamp: 5964
hardirqs last enabled at (5963): [<ffff200008e59e40>] mutex_lock_nested+0x6e8/0x6f0
hardirqs last disabled at (5964): [<ffff200008e623f0>] _raw_spin_lock_irqsave+0x24/0x68
softirqs last enabled at (5502): [<ffff200008081838>] __do_softirq+0x560/0x10c0
softirqs last disabled at (5495): [<ffff2000080c2e78>] irq_exit+0x160/0x25c
Preemption disabled at:[ 62.904063] [<ffff200008be4d48>] snd_pcm_stream_lock+0xb4/0xc0
CPU: 2 PID: 2242 Comm: aplay Tainted: G B C 4.9.54+ #186
Hardware name: Renesas Salvator-X board based on r8a7795 (DT)
Call trace:
[<ffff20000808fe48>] dump_backtrace+0x0/0x37c
[<ffff2000080901d8>] show_stack+0x14/0x1c
[<ffff2000086f4458>] dump_stack+0xfc/0x154
[<ffff2000081134a0>] ___might_sleep+0x57c/0x58c
[<ffff2000081136b8>] __might_sleep+0x208/0x21c
[<ffff200008e5980c>] mutex_lock_nested+0xb4/0x6f0
[<ffff2000087cac74>] clk_prepare_lock+0xb0/0x184
[<ffff2000087cb094>] clk_core_get_rate+0x14/0x54
[<ffff2000087cb0f4>] clk_get_rate+0x20/0x34
[<ffff20000113aa00>] rsnd_adg_ssi_clk_try_start+0x158/0x4f8 [snd_soc_rcar]
[<ffff20000113da00>] rsnd_ssi_init+0x668/0x7a0 [snd_soc_rcar]
[<ffff200001133ff4>] rsnd_soc_dai_trigger+0x4bc/0xcf8 [snd_soc_rcar]
[<ffff200008c1af24>] soc_pcm_trigger+0x2a4/0x2d4
Fixes: e7d850dd10f4 ("ASoC: rsnd: use mod base common method on SSI-parent")
Signed-off-by: Jiada Wang <jiada_wang at mentor.com>
Signed-off-by: Timo Wischer <twischer at de.adit-jv.com>
[Kuninori: tidyup for upstream]
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
Tested-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx at renesas.com>
---
sound/soc/sh/rcar/core.c | 11 +++++++++++
sound/soc/sh/rcar/rsnd.h | 7 +++++++
sound/soc/sh/rcar/ssi.c | 16 ++++++++++------
3 files changed, 28 insertions(+), 6 deletions(-)
diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
index c66b3da..299fb45 100644
--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -955,12 +955,23 @@ static void rsnd_soc_dai_shutdown(struct snd_pcm_substream *substream,
rsnd_dai_stream_quit(io);
}
+static int rsnd_soc_dai_prepare(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct rsnd_priv *priv = rsnd_dai_to_priv(dai);
+ struct rsnd_dai *rdai = rsnd_dai_to_rdai(dai);
+ struct rsnd_dai_stream *io = rsnd_rdai_to_io(rdai, substream);
+
+ return rsnd_dai_call(prepare, io, priv);
+}
+
static const struct snd_soc_dai_ops rsnd_soc_dai_ops = {
.startup = rsnd_soc_dai_startup,
.shutdown = rsnd_soc_dai_shutdown,
.trigger = rsnd_soc_dai_trigger,
.set_fmt = rsnd_soc_dai_set_fmt,
.set_tdm_slot = rsnd_soc_set_dai_tdm_slot,
+ .prepare = rsnd_soc_dai_prepare,
};
void rsnd_parse_connect_common(struct rsnd_dai *rdai,
diff --git a/sound/soc/sh/rcar/rsnd.h b/sound/soc/sh/rcar/rsnd.h
index 7ff58b0..7a04b19 100644
--- a/sound/soc/sh/rcar/rsnd.h
+++ b/sound/soc/sh/rcar/rsnd.h
@@ -301,6 +301,9 @@ struct rsnd_mod_ops {
int (*nolock_stop)(struct rsnd_mod *mod,
struct rsnd_dai_stream *io,
struct rsnd_priv *priv);
+ int (*prepare)(struct rsnd_mod *mod,
+ struct rsnd_dai_stream *io,
+ struct rsnd_priv *priv);
};
struct rsnd_dai_stream;
@@ -330,6 +333,7 @@ struct rsnd_mod {
* H 0: fallback
* H 0: hw_params
* H 0: pointer
+ * H 0: prepare
*/
#define __rsnd_mod_shift_nolock_start 0
#define __rsnd_mod_shift_nolock_stop 0
@@ -344,6 +348,7 @@ struct rsnd_mod {
#define __rsnd_mod_shift_fallback 28 /* always called */
#define __rsnd_mod_shift_hw_params 28 /* always called */
#define __rsnd_mod_shift_pointer 28 /* always called */
+#define __rsnd_mod_shift_prepare 28 /* always called */
#define __rsnd_mod_add_probe 0
#define __rsnd_mod_add_remove 0
@@ -358,6 +363,7 @@ struct rsnd_mod {
#define __rsnd_mod_add_fallback 0
#define __rsnd_mod_add_hw_params 0
#define __rsnd_mod_add_pointer 0
+#define __rsnd_mod_add_prepare 0
#define __rsnd_mod_call_probe 0
#define __rsnd_mod_call_remove 0
@@ -372,6 +378,7 @@ struct rsnd_mod {
#define __rsnd_mod_call_pointer 0
#define __rsnd_mod_call_nolock_start 0
#define __rsnd_mod_call_nolock_stop 1
+#define __rsnd_mod_call_prepare 0
#define rsnd_mod_to_priv(mod) ((mod)->priv)
#define rsnd_mod_name(mod) ((mod)->ops->name)
diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
index 85da4fc..3adcc4f 100644
--- a/sound/soc/sh/rcar/ssi.c
+++ b/sound/soc/sh/rcar/ssi.c
@@ -306,7 +306,7 @@ static int rsnd_ssi_master_clk_start(struct rsnd_mod *mod,
if (rsnd_ssi_is_multi_slave(mod, io))
return 0;
- if (ssi->usrcnt > 1) {
+ if (ssi->rate) {
if (ssi->rate != rate) {
dev_err(dev, "SSI parent/child should use same rate\n");
return -EINVAL;
@@ -464,7 +464,6 @@ static int rsnd_ssi_init(struct rsnd_mod *mod,
struct rsnd_priv *priv)
{
struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
- int ret;
if (!rsnd_ssi_is_run_mods(mod, io))
return 0;
@@ -473,10 +472,6 @@ static int rsnd_ssi_init(struct rsnd_mod *mod,
rsnd_mod_power_on(mod);
- ret = rsnd_ssi_master_clk_start(mod, io);
- if (ret < 0)
- return ret;
-
rsnd_ssi_config_init(mod, io);
rsnd_ssi_register_setup(mod);
@@ -872,6 +867,13 @@ static int rsnd_ssi_pio_pointer(struct rsnd_mod *mod,
return 0;
}
+static int rsnd_ssi_prepare(struct rsnd_mod *mod,
+ struct rsnd_dai_stream *io,
+ struct rsnd_priv *priv)
+{
+ return rsnd_ssi_master_clk_start(mod, io);
+}
+
static struct rsnd_mod_ops rsnd_ssi_pio_ops = {
.name = SSI_NAME,
.probe = rsnd_ssi_common_probe,
@@ -884,6 +886,7 @@ static struct rsnd_mod_ops rsnd_ssi_pio_ops = {
.pointer = rsnd_ssi_pio_pointer,
.pcm_new = rsnd_ssi_pcm_new,
.hw_params = rsnd_ssi_hw_params,
+ .prepare = rsnd_ssi_prepare,
};
static int rsnd_ssi_dma_probe(struct rsnd_mod *mod,
@@ -959,6 +962,7 @@ static struct rsnd_mod_ops rsnd_ssi_dma_ops = {
.pcm_new = rsnd_ssi_pcm_new,
.fallback = rsnd_ssi_fallback,
.hw_params = rsnd_ssi_hw_params,
+ .prepare = rsnd_ssi_prepare,
};
int rsnd_ssi_is_dma_mode(struct rsnd_mod *mod)
--
2.7.4
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