2020-06-06 21:06:07

by Tom Rix

Subject: [PATCH 0/1] fpga: dfl: Fix dead store

From: Tom Rix <[email protected]>

Repo linux-next
Tag next-20200605

A couple of fixes for dead stores found by clang's sa tool scan-build

Tom Rix (1):
Fix dead store

drivers/fpga/fpga-bridge.c | 6 ++----
drivers/fpga/fpga-mgr.c | 4 +---
2 files changed, 3 insertions(+), 7 deletions(-)

--
2.26.0

2020-06-06 21:07:44

by Tom Rix

Subject: [PATCH 1/1] fpga: dfl: Fix dead store

From: Tom Rix <[email protected]>

Using clang's scan-build/view this issue was flagged in fpga-mgr.c

drivers/fpga/fpga-mgr.c:585:3: warning: Value stored to 'ret' is never read [deadcode.DeadStores]
ret = id;

A similar issue was flagged in fpga-bridge.

So remove the unused stores.

Signed-off-by: Tom Rix <[email protected]>
---
drivers/fpga/fpga-bridge.c | 6 ++----
drivers/fpga/fpga-mgr.c | 4 +---
2 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 4bab9028940a..2deccacc3aa7 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -328,7 +328,7 @@ struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
void *priv)
{
struct fpga_bridge *bridge;
- int id, ret = 0;
+ int id, ret;

if (!name || !strlen(name)) {
dev_err(dev, "Attempt to register with no name!\n");
@@ -340,10 +340,8 @@ struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
return NULL;

id = ida_simple_get(&fpga_bridge_ida, 0, 0, GFP_KERNEL);
- if (id < 0) {
- ret = id;
+ if (id < 0)
goto error_kfree;
- }

mutex_init(&bridge->mutex);
INIT_LIST_HEAD(&bridge->node);
diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index e05104f5e40c..f38bab01432e 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -581,10 +581,8 @@ struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
return NULL;

id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL);
- if (id < 0) {
- ret = id;
+ if (id < 0)
goto error_kfree;
- }

mutex_init(&mgr->ref_mutex);

--
2.26.0

2020-06-08 01:56:00

by Wu Hao

Subject: RE: [PATCH 1/1] fpga: dfl: Fix dead store

> -----Original Message-----
> From: [email protected] <[email protected]>
> On Behalf Of [email protected]
> Sent: Sunday, June 7, 2020 5:03 AM
> To: [email protected]
> Cc: [email protected]; [email protected]; Tom Rix
> <[email protected]>
> Subject: [PATCH 1/1] fpga: dfl: Fix dead store
>

Thanks for this patch, looks good to me, but this patch is not related to
dfl, so please remove dfl from the title to avoid confusion. : )
or maybe it can be split into two patches:
fpga: mgr: xxx
fpga: bridge: xxx

Thanks
Hao

> From: Tom Rix <[email protected]>
>
> Using clang's scan-build/view this issue was flagged in fpga-mgr.c
>
> drivers/fpga/fpga-mgr.c:585:3: warning: Value stored to 'ret' is never read
> [deadcode.DeadStores]
> ret = id;
>
> A similar issue was flagged in fpga-bridge.
>
> So remove the unused stores.
>
> Signed-off-by: Tom Rix <[email protected]>
> ---
> drivers/fpga/fpga-bridge.c | 6 ++----
> drivers/fpga/fpga-mgr.c | 4 +---
> 2 files changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
> index 4bab9028940a..2deccacc3aa7 100644
> --- a/drivers/fpga/fpga-bridge.c
> +++ b/drivers/fpga/fpga-bridge.c
> @@ -328,7 +328,7 @@ struct fpga_bridge *fpga_bridge_create(struct device
> *dev, const char *name,
> void *priv)
> {
> struct fpga_bridge *bridge;
> - int id, ret = 0;
> + int id, ret;
>
> if (!name || !strlen(name)) {
> dev_err(dev, "Attempt to register with no name!\n");
> @@ -340,10 +340,8 @@ struct fpga_bridge *fpga_bridge_create(struct
> device *dev, const char *name,
> return NULL;
>
> id = ida_simple_get(&fpga_bridge_ida, 0, 0, GFP_KERNEL);
> - if (id < 0) {
> - ret = id;
> + if (id < 0)
> goto error_kfree;
> - }
>
> mutex_init(&bridge->mutex);
> INIT_LIST_HEAD(&bridge->node);
> diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
> index e05104f5e40c..f38bab01432e 100644
> --- a/drivers/fpga/fpga-mgr.c
> +++ b/drivers/fpga/fpga-mgr.c
> @@ -581,10 +581,8 @@ struct fpga_manager *fpga_mgr_create(struct
> device *dev, const char *name,
> return NULL;
>
> id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL);
> - if (id < 0) {
> - ret = id;
> + if (id < 0)
> goto error_kfree;
> - }
>
> mutex_init(&mgr->ref_mutex);
>
> --
> 2.26.0