2021-05-08 10:42:51

by Jiapeng Chong

Subject: [PATCH v2] sysctl: Remove redundant assignment to first

Variable first is set to '0', but this value is never read as it is
not used later on, hence it is a redundant assignment and can be
removed.

Clean up the following clang-analyzer warning:

kernel/sysctl.c:1562:4: warning: Value stored to 'first' is never read
[clang-analyzer-deadcode.DeadStores].

Reported-by: Abaci Robot <[email protected]>
Signed-off-by: Jiapeng Chong <[email protected]>
---
Changes in v2:
-For the follow advice: https://lore.kernel.org/patchwork/patch/1422497/

kernel/sysctl.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 14edf84..23de0d9 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1474,7 +1474,6 @@ int proc_do_large_bitmap(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
int err = 0;
- bool first = 1;
size_t left = *lenp;
unsigned long bitmap_len = table->maxlen;
unsigned long *bitmap = *(unsigned long **) table->data;
@@ -1559,12 +1558,12 @@ int proc_do_large_bitmap(struct ctl_table *table, int write,
}

bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
- first = 0;
proc_skip_char(&p, &left, '\n');
}
left += skipped;
} else {
unsigned long bit_a, bit_b = 0;
+ bool first = 1;

while (left) {
bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
--
1.8.3.1

2021-05-12 07:04:39

by Luis Chamberlain

Subject: Re: [PATCH v2] sysctl: Remove redundant assignment to first

On Sat, May 08, 2021 at 06:33:10PM +0800, Jiapeng Chong wrote:
> Variable first is set to '0', but this value is never read as it is
> not used later on, hence it is a redundant assignment and can be
> removed.
>
> Clean up the following clang-analyzer warning:
>
> kernel/sysctl.c:1562:4: warning: Value stored to 'first' is never read
> [clang-analyzer-deadcode.DeadStores].
>
> Reported-by: Abaci Robot <[email protected]>
> Signed-off-by: Jiapeng Chong <[email protected]>

To re-iterate, this does not fix anything, it is just a clean up.

Acked-by: Luis Chamberlain <[email protected]>

Luis

> ---
> Changes in v2:
> -For the follow advice: https://lore.kernel.org/patchwork/patch/1422497/
>
> kernel/sysctl.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 14edf84..23de0d9 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -1474,7 +1474,6 @@ int proc_do_large_bitmap(struct ctl_table *table, int write,
> void *buffer, size_t *lenp, loff_t *ppos)
> {
> int err = 0;
> - bool first = 1;
> size_t left = *lenp;
> unsigned long bitmap_len = table->maxlen;
> unsigned long *bitmap = *(unsigned long **) table->data;
> @@ -1559,12 +1558,12 @@ int proc_do_large_bitmap(struct ctl_table *table, int write,
> }
>
> bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
> - first = 0;
> proc_skip_char(&p, &left, '\n');
> }
> left += skipped;
> } else {
> unsigned long bit_a, bit_b = 0;
> + bool first = 1;
>
> while (left) {
> bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
> --
> 1.8.3.1
>