[PATCH 5/6] firedtv: remove check for interrupting signal

From: Stefan Richter
Date: Wed Nov 18 2009 - 14:03:25 EST


FCP transactions as well as CMP transactions were serialized with
mutex_lock_interruptible. It is extremely unlikly though that a signal
will arrive while a concurrent process holds the mutex. And even if one
does, the duration of a transaction is reasonably short (1.2 seconds if
all retries time out, usually much shorter).

Hence simplify the code to plain mutex_lock.

Signed-off-by: Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx>
---
drivers/media/dvb/firewire/firedtv-avc.c | 51 ++++++++---------------
1 file changed, 17 insertions(+), 34 deletions(-)

Index: linux-2.6.32-rc7/drivers/media/dvb/firewire/firedtv-avc.c
===================================================================
--- linux-2.6.32-rc7.orig/drivers/media/dvb/firewire/firedtv-avc.c
+++ linux-2.6.32-rc7/drivers/media/dvb/firewire/firedtv-avc.c
@@ -542,8 +542,7 @@ int avc_tuner_dsd(struct firedtv *fdtv,
struct avc_command_frame *c = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -584,8 +583,7 @@ int avc_tuner_set_pids(struct firedtv *f
if (pidc > 16 && pidc != 0xff)
return -EINVAL;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -629,8 +627,7 @@ int avc_tuner_get_ts(struct firedtv *fdt
struct avc_command_frame *c = (void *)fdtv->avc_data;
int ret, sl;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -670,8 +667,7 @@ int avc_identify_subunit(struct firedtv
struct avc_response_frame *r = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -712,8 +708,7 @@ int avc_tuner_status(struct firedtv *fdt
struct avc_response_frame *r = (void *)fdtv->avc_data;
int length, ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -795,8 +790,7 @@ int avc_lnb_control(struct firedtv *fdtv
struct avc_response_frame *r = (void *)fdtv->avc_data;
int i, j, k, ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -844,8 +838,7 @@ int avc_register_remote_control(struct f
struct avc_command_frame *c = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -883,8 +876,7 @@ int avc_tuner_host2ca(struct firedtv *fd
struct avc_command_frame *c = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -943,8 +935,7 @@ int avc_ca_app_info(struct firedtv *fdtv
struct avc_response_frame *r = (void *)fdtv->avc_data;
int pos, ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -986,8 +977,7 @@ int avc_ca_info(struct firedtv *fdtv, ch
struct avc_response_frame *r = (void *)fdtv->avc_data;
int pos, ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -1028,8 +1018,7 @@ int avc_ca_reset(struct firedtv *fdtv)
struct avc_command_frame *c = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -1073,8 +1062,7 @@ int avc_ca_pmt(struct firedtv *fdtv, cha
if (unlikely(avc_debug & AVC_DEBUG_APPLICATION_PMT))
debug_pmt(msg, length);

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -1196,8 +1184,7 @@ int avc_ca_get_time_date(struct firedtv
struct avc_response_frame *r = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -1233,8 +1220,7 @@ int avc_ca_enter_menu(struct firedtv *fd
struct avc_command_frame *c = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -1267,8 +1253,7 @@ int avc_ca_get_mmi(struct firedtv *fdtv,
struct avc_response_frame *r = (void *)fdtv->avc_data;
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

memset(c, 0, sizeof(*c));

@@ -1306,8 +1291,7 @@ static int cmp_read(struct firedtv *fdtv
{
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

ret = fdtv->backend->read(fdtv, addr, data);
if (ret < 0)
@@ -1322,8 +1306,7 @@ static int cmp_lock(struct firedtv *fdtv
{
int ret;

- if (mutex_lock_interruptible(&fdtv->avc_mutex))
- return -EINTR;
+ mutex_lock(&fdtv->avc_mutex);

/* data[] is stack-allocated and should not be DMA-mapped. */
memcpy(fdtv->avc_data, data, 8);

--
Stefan Richter
-=====-==--= =-== =--=-
http://arcgraph.de/sr/

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