[PATCH 11/13] random: simplify sysctl declaration with register_sysctl_subdir()

From: Luis Chamberlain
Date: Fri May 29 2020 - 03:41:28 EST


From: Xiaoming Ni <nixiaoming@xxxxxxxxxx>

Move random_table sysctl from kernel/sysctl.c to drivers/char/random.c
and use register_sysctl_subdir() to help remove the clutter out of
kernel/sysctl.c.

Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
---
drivers/char/random.c | 14 ++++++++++++--
include/linux/sysctl.h | 1 -
kernel/sysctl.c | 5 -----
3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index a7cf6aa65908..73fd4b6e9c18 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -2101,8 +2101,7 @@ static int proc_do_entropy(struct ctl_table *table, int write,
}

static int sysctl_poolsize = INPUT_POOL_WORDS * 32;
-extern struct ctl_table random_table[];
-struct ctl_table random_table[] = {
+static struct ctl_table random_table[] = {
{
.procname = "poolsize",
.data = &sysctl_poolsize,
@@ -2164,6 +2163,17 @@ struct ctl_table random_table[] = {
#endif
{ }
};
+
+/*
+ * rand_initialize() is called before sysctl_init(),
+ * so we cannot call register_sysctl_init() in rand_initialize()
+ */
+static int __init random_sysctls_init(void)
+{
+ register_sysctl_subdir("kernel", "random", random_table);
+ return 0;
+}
+device_initcall(random_sysctls_init);
#endif /* CONFIG_SYSCTL */

struct batched_entropy {
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index e5364b69dd95..33a471b56345 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -216,7 +216,6 @@ extern int unaligned_dump_stack;
extern int no_unaligned_warning;

extern struct ctl_table sysctl_mount_point[];
-extern struct ctl_table random_table[];

#else /* CONFIG_SYSCTL */
static inline struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 5c116904feb7..f9a35325d5d5 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2078,11 +2078,6 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = sysctl_max_threads,
},
- {
- .procname = "random",
- .mode = 0555,
- .child = random_table,
- },
{
.procname = "usermodehelper",
.mode = 0555,
--
2.26.2