[PATCH] ALSA: HDA: Improve unlocking of a mutex in hdmi_pcm_open()

From: SF Markus Elfring
Date: Wed Nov 15 2017 - 09:02:13 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Wed, 15 Nov 2017 14:46:19 +0100

* Add a jump target so that a call of the function "mutex_unlock" is stored
only twice in this function implementation.

* Replace four calls by goto statements.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
sound/pci/hda/patch_hdmi.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index c19c81d230bd..f1c0b6cab90a 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1205,8 +1205,8 @@ static int hdmi_pcm_open(struct hda_pcm_stream *hinfo,
pin_idx = hinfo_to_pin_index(codec, hinfo);
if (!spec->dyn_pcm_assign) {
if (snd_BUG_ON(pin_idx < 0)) {
- mutex_unlock(&spec->pcm_lock);
- return -EINVAL;
+ err = -EINVAL;
+ goto unlock;
}
} else {
/* no pin is assigned to the PCM
@@ -1214,16 +1214,13 @@ static int hdmi_pcm_open(struct hda_pcm_stream *hinfo,
*/
if (pin_idx < 0) {
err = hdmi_pcm_open_no_pin(hinfo, codec, substream);
- mutex_unlock(&spec->pcm_lock);
- return err;
+ goto unlock;
}
}

err = hdmi_choose_cvt(codec, pin_idx, &cvt_idx);
- if (err < 0) {
- mutex_unlock(&spec->pcm_lock);
- return err;
- }
+ if (err < 0)
+ goto unlock;

per_cvt = get_cvt(spec, cvt_idx);
/* Claim converter */
@@ -1260,8 +1257,8 @@ static int hdmi_pcm_open(struct hda_pcm_stream *hinfo,
per_cvt->assigned = 0;
hinfo->nid = 0;
snd_hda_spdif_ctls_unassign(codec, pcm_idx);
- mutex_unlock(&spec->pcm_lock);
- return -ENODEV;
+ err = -ENODEV;
+ goto unlock;
}
}

@@ -1275,6 +1272,10 @@ static int hdmi_pcm_open(struct hda_pcm_stream *hinfo,
snd_pcm_hw_constraint_step(substream->runtime, 0,
SNDRV_PCM_HW_PARAM_CHANNELS, 2);
return 0;
+
+unlock:
+ mutex_unlock(&spec->pcm_lock);
+ return err;
}

/*
--
2.15.0