eventpoll: simplify sysctl declaration with register_sysctl()
The kernel/sysctl.c is a kitchen sink where everyone leaves their dirty
dishes, this makes it very difficult to maintain.
To help with this maintenance let's start by moving sysctls to places
where they actually belong. The proc sysctl maintainers do not want to
know what sysctl knobs you wish to add for your own piece of code, we
just care about the core logic.
So move the epoll_table sysctl to fs/eventpoll.c and use
register_sysctl().
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Xiaoming Ni <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Amir Goldstein <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Antti Palosaari <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Benjamin LaHaise <[email protected]>
Cc: Clemens Ladisch <[email protected]>
Cc: David Airlie <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Iurii Zaikin <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Jan Kara <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Joseph Qi <[email protected]>
Cc: Julia Lawall <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Lukas Middendorf <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Paul Turner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Phillip Potter <[email protected]>
Cc: Qing Wang <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Sebastian Reichel <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Stephen Kitt <[email protected]>
Cc: Tetsuo Handa <[email protected]>
Cc: Douglas Gilbert <[email protected]>
Cc: James E.J. Bottomley <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: John Ogness <[email protected]>
Cc: Martin K. Petersen <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Steven Rostedt (VMware) <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: "Theodore Ts'o" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 06f4c5a..e2daa94 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -307,7 +307,7 @@ static void unlist_file(struct epitems_head *head)
static long long_zero;
static long long_max = LONG_MAX;
-struct ctl_table epoll_table[] = {
+static struct ctl_table epoll_table[] = {
{
.procname = "max_user_watches",
.data = &max_user_watches,
@@ -319,6 +319,13 @@ struct ctl_table epoll_table[] = {
},
{ }
};
+
+static void __init epoll_sysctls_init(void)
+{
+ register_sysctl("fs/epoll", epoll_table);
+}
+#else
+#define epoll_sysctls_init() do { } while (0)
#endif /* CONFIG_SYSCTL */
static const struct file_operations eventpoll_fops;
@@ -2378,6 +2385,7 @@ static int __init eventpoll_init(void)
/* Allocates slab cache used to allocate "struct eppoll_entry" */
pwq_cache = kmem_cache_create("eventpoll_pwq",
sizeof(struct eppoll_entry), 0, SLAB_PANIC|SLAB_ACCOUNT, NULL);
+ epoll_sysctls_init();
ephead_cache = kmem_cache_create("ep_head",
sizeof(struct epitems_head), 0, SLAB_PANIC|SLAB_ACCOUNT, NULL);
diff --git a/include/linux/poll.h b/include/linux/poll.h
index 1cdc32b..a9e0e1c 100644
--- a/include/linux/poll.h
+++ b/include/linux/poll.h
@@ -8,12 +8,10 @@
#include <linux/wait.h>
#include <linux/string.h>
#include <linux/fs.h>
-#include <linux/sysctl.h>
#include <linux/uaccess.h>
#include <uapi/linux/poll.h>
#include <uapi/linux/eventpoll.h>
-extern struct ctl_table epoll_table[]; /* for sysctl */
/* ~832 bytes of stack space used max in sys_select/sys_poll before allocating
additional memory. */
#ifdef __clang__
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 47cf70c..6dd0f27 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -219,7 +219,6 @@ extern int no_unaligned_warning;
extern struct ctl_table sysctl_mount_point[];
extern struct ctl_table random_table[];
extern struct ctl_table firmware_config_table[];
-extern struct ctl_table epoll_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 2ee0e76..09fa722 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -3093,13 +3093,6 @@ static struct ctl_table fs_table[] = {
.proc_handler = proc_dointvec,
},
#endif
-#ifdef CONFIG_EPOLL
- {
- .procname = "epoll",
- .mode = 0555,
- .child = epoll_table,
- },
-#endif
#endif
{
.procname = "protected_symlinks",
