In some functions, it's unnecessary to declare 'err'
and 'ret' variables at the same time. This patch mainly
to simplify the issue of such declarations by reusing
one variable.
Signed-off-by: Rongwei Wang <[email protected]>
---
mm/damon/dbgfs.c | 66 +++++++++++++++++++++++-------------------------
1 file changed, 31 insertions(+), 35 deletions(-)
diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c
index 28d6abf27763..5cd4932800df 100644
--- a/mm/damon/dbgfs.c
+++ b/mm/damon/dbgfs.c
@@ -69,8 +69,7 @@ static ssize_t dbgfs_attrs_write(struct file *file,
struct damon_ctx *ctx = file->private_data;
unsigned long s, a, r, minr, maxr;
char *kbuf;
- ssize_t ret = count;
- int err;
+ ssize_t ret;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -88,9 +87,9 @@ static ssize_t dbgfs_attrs_write(struct file *file,
goto unlock_out;
}
- err = damon_set_attrs(ctx, s, a, r, minr, maxr);
- if (err)
- ret = err;
+ ret = damon_set_attrs(ctx, s, a, r, minr, maxr);
+ if (!ret)
+ ret = count;
unlock_out:
mutex_unlock(&ctx->kdamond_lock);
out:
@@ -220,14 +219,13 @@ static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf,
struct damon_ctx *ctx = file->private_data;
char *kbuf;
struct damos **schemes;
- ssize_t nr_schemes = 0, ret = count;
- int err;
+ ssize_t nr_schemes = 0, ret;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
return PTR_ERR(kbuf);
- schemes = str_to_schemes(kbuf, ret, &nr_schemes);
+ schemes = str_to_schemes(kbuf, count, &nr_schemes);
if (!schemes) {
ret = -EINVAL;
goto out;
@@ -239,11 +237,12 @@ static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf,
goto unlock_out;
}
- err = damon_set_schemes(ctx, schemes, nr_schemes);
- if (err)
- ret = err;
- else
+ ret = damon_set_schemes(ctx, schemes, nr_schemes);
+ if (!ret) {
+ ret = count;
nr_schemes = 0;
+ }
+
unlock_out:
mutex_unlock(&ctx->kdamond_lock);
free_schemes_arr(schemes, nr_schemes);
@@ -342,9 +341,8 @@ static ssize_t dbgfs_target_ids_write(struct file *file,
char *kbuf, *nrs;
unsigned long *targets;
ssize_t nr_targets;
- ssize_t ret = count;
+ ssize_t ret;
int i;
- int err;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -352,7 +350,7 @@ static ssize_t dbgfs_target_ids_write(struct file *file,
nrs = kbuf;
- targets = str_to_target_ids(nrs, ret, &nr_targets);
+ targets = str_to_target_ids(nrs, count, &nr_targets);
if (!targets) {
ret = -ENOMEM;
goto out;
@@ -378,11 +376,12 @@ static ssize_t dbgfs_target_ids_write(struct file *file,
goto unlock_out;
}
- err = damon_set_targets(ctx, targets, nr_targets);
- if (err) {
+ ret = damon_set_targets(ctx, targets, nr_targets);
+ if (ret) {
if (targetid_is_pid(ctx))
dbgfs_put_pids(targets, nr_targets);
- ret = err;
+ } else {
+ ret = count;
}
unlock_out:
@@ -548,8 +547,7 @@ static ssize_t dbgfs_mk_context_write(struct file *file,
{
char *kbuf;
char *ctx_name;
- ssize_t ret = count;
- int err;
+ ssize_t ret;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -567,9 +565,9 @@ static ssize_t dbgfs_mk_context_write(struct file *file,
}
mutex_lock(&damon_dbgfs_lock);
- err = dbgfs_mk_context(ctx_name);
- if (err)
- ret = err;
+ ret = dbgfs_mk_context(ctx_name);
+ if (!ret)
+ ret = count;
mutex_unlock(&damon_dbgfs_lock);
out:
@@ -638,8 +636,7 @@ static ssize_t dbgfs_rm_context_write(struct file *file,
const char __user *buf, size_t count, loff_t *ppos)
{
char *kbuf;
- ssize_t ret = count;
- int err;
+ ssize_t ret;
char *ctx_name;
kbuf = user_input_str(buf, count, ppos);
@@ -658,9 +655,9 @@ static ssize_t dbgfs_rm_context_write(struct file *file,
}
mutex_lock(&damon_dbgfs_lock);
- err = dbgfs_rm_context(ctx_name);
- if (err)
- ret = err;
+ ret = dbgfs_rm_context(ctx_name);
+ if (!ret)
+ ret = count;
mutex_unlock(&damon_dbgfs_lock);
out:
@@ -684,9 +681,8 @@ static ssize_t dbgfs_monitor_on_read(struct file *file,
static ssize_t dbgfs_monitor_on_write(struct file *file,
const char __user *buf, size_t count, loff_t *ppos)
{
- ssize_t ret = count;
+ ssize_t ret;
char *kbuf;
- int err;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -699,14 +695,14 @@ static ssize_t dbgfs_monitor_on_write(struct file *file,
}
if (!strncmp(kbuf, "on", count))
- err = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs);
+ ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs);
else if (!strncmp(kbuf, "off", count))
- err = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs);
+ ret = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs);
else
- err = -EINVAL;
+ ret = -EINVAL;
- if (err)
- ret = err;
+ if (!ret)
+ ret = count;
kfree(kbuf);
return ret;
}
--
2.27.0
On Thu, 14 Oct 2021 10:03:33 +0800 Rongwei Wang <[email protected]> wrote:
> In some functions, it's unnecessary to declare 'err'
> and 'ret' variables at the same time. This patch mainly
> to simplify the issue of such declarations by reusing
> one variable.
>
> Signed-off-by: Rongwei Wang <[email protected]>
Looks good to me. However, this doesn't cleanly applicable on latest -mm tree.
I will post a rebased version as a reply to this.
Thanks,
SJ
[...]
From: Rongwei Wang <[email protected]>
In some functions, it's unnecessary to declare 'err'
and 'ret' variables at the same time. This patch mainly
to simplify the issue of such declarations by reusing
one variable.
Signed-off-by: Rongwei Wang <[email protected]>
Signed-off-by: SeongJae Park <[email protected]>
---
Changes from v2
(https://lore.kernel.org/linux-mm/[email protected]/)
- Rebased on latest -mm tree (v5.15-rc5-mmots-2021-10-13-19-55)
mm/damon/dbgfs.c | 66 +++++++++++++++++++++++-------------------------
1 file changed, 31 insertions(+), 35 deletions(-)
diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c
index 38188347d8ab..c90988a20fa4 100644
--- a/mm/damon/dbgfs.c
+++ b/mm/damon/dbgfs.c
@@ -69,8 +69,7 @@ static ssize_t dbgfs_attrs_write(struct file *file,
struct damon_ctx *ctx = file->private_data;
unsigned long s, a, r, minr, maxr;
char *kbuf;
- ssize_t ret = count;
- int err;
+ ssize_t ret;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -88,9 +87,9 @@ static ssize_t dbgfs_attrs_write(struct file *file,
goto unlock_out;
}
- err = damon_set_attrs(ctx, s, a, r, minr, maxr);
- if (err)
- ret = err;
+ ret = damon_set_attrs(ctx, s, a, r, minr, maxr);
+ if (!ret)
+ ret = count;
unlock_out:
mutex_unlock(&ctx->kdamond_lock);
out:
@@ -220,14 +219,13 @@ static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf,
struct damon_ctx *ctx = file->private_data;
char *kbuf;
struct damos **schemes;
- ssize_t nr_schemes = 0, ret = count;
- int err;
+ ssize_t nr_schemes = 0, ret;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
return PTR_ERR(kbuf);
- schemes = str_to_schemes(kbuf, ret, &nr_schemes);
+ schemes = str_to_schemes(kbuf, count, &nr_schemes);
if (!schemes) {
ret = -EINVAL;
goto out;
@@ -239,11 +237,12 @@ static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf,
goto unlock_out;
}
- err = damon_set_schemes(ctx, schemes, nr_schemes);
- if (err)
- ret = err;
- else
+ ret = damon_set_schemes(ctx, schemes, nr_schemes);
+ if (!ret) {
+ ret = count;
nr_schemes = 0;
+ }
+
unlock_out:
mutex_unlock(&ctx->kdamond_lock);
free_schemes_arr(schemes, nr_schemes);
@@ -343,9 +342,8 @@ static ssize_t dbgfs_target_ids_write(struct file *file,
char *kbuf, *nrs;
unsigned long *targets;
ssize_t nr_targets;
- ssize_t ret = count;
+ ssize_t ret;
int i;
- int err;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -358,7 +356,7 @@ static ssize_t dbgfs_target_ids_write(struct file *file,
scnprintf(kbuf, count, "42 ");
}
- targets = str_to_target_ids(nrs, ret, &nr_targets);
+ targets = str_to_target_ids(nrs, count, &nr_targets);
if (!targets) {
ret = -ENOMEM;
goto out;
@@ -393,11 +391,12 @@ static ssize_t dbgfs_target_ids_write(struct file *file,
else
damon_pa_set_primitives(ctx);
- err = damon_set_targets(ctx, targets, nr_targets);
- if (err) {
+ ret = damon_set_targets(ctx, targets, nr_targets);
+ if (ret) {
if (id_is_pid)
dbgfs_put_pids(targets, nr_targets);
- ret = err;
+ } else {
+ ret = count;
}
unlock_out:
@@ -715,8 +714,7 @@ static ssize_t dbgfs_mk_context_write(struct file *file,
{
char *kbuf;
char *ctx_name;
- ssize_t ret = count;
- int err;
+ ssize_t ret;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -734,9 +732,9 @@ static ssize_t dbgfs_mk_context_write(struct file *file,
}
mutex_lock(&damon_dbgfs_lock);
- err = dbgfs_mk_context(ctx_name);
- if (err)
- ret = err;
+ ret = dbgfs_mk_context(ctx_name);
+ if (!ret)
+ ret = count;
mutex_unlock(&damon_dbgfs_lock);
out:
@@ -805,8 +803,7 @@ static ssize_t dbgfs_rm_context_write(struct file *file,
const char __user *buf, size_t count, loff_t *ppos)
{
char *kbuf;
- ssize_t ret = count;
- int err;
+ ssize_t ret;
char *ctx_name;
kbuf = user_input_str(buf, count, ppos);
@@ -825,9 +822,9 @@ static ssize_t dbgfs_rm_context_write(struct file *file,
}
mutex_lock(&damon_dbgfs_lock);
- err = dbgfs_rm_context(ctx_name);
- if (err)
- ret = err;
+ ret = dbgfs_rm_context(ctx_name);
+ if (!ret)
+ ret = count;
mutex_unlock(&damon_dbgfs_lock);
out:
@@ -851,9 +848,8 @@ static ssize_t dbgfs_monitor_on_read(struct file *file,
static ssize_t dbgfs_monitor_on_write(struct file *file,
const char __user *buf, size_t count, loff_t *ppos)
{
- ssize_t ret = count;
+ ssize_t ret;
char *kbuf;
- int err;
kbuf = user_input_str(buf, count, ppos);
if (IS_ERR(kbuf))
@@ -866,14 +862,14 @@ static ssize_t dbgfs_monitor_on_write(struct file *file,
}
if (!strncmp(kbuf, "on", count))
- err = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs);
+ ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs);
else if (!strncmp(kbuf, "off", count))
- err = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs);
+ ret = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs);
else
- err = -EINVAL;
+ ret = -EINVAL;
- if (err)
- ret = err;
+ if (!ret)
+ ret = count;
kfree(kbuf);
return ret;
}
--
2.17.1