The show_unhandled_signals sysctl is the only sysctl for debug
left on kernel/sysctl.c. We've been moving the syctls out from
kernel/sysctl.c so to help avoid merge conflicts as the shared
array gets out of hand.
This change incurs simplifies sysctl registration by localizing
it where it should go for a penalty in size of increasing the
kernel by 23 bytes, we accept this given recent cleanups have
actually already saved us 1465 bytes in the prior commits.
./scripts/bloat-o-meter vmlinux.3-remove-dev-table vmlinux.4-remove-debug-table
add/remove: 3/1 grow/shrink: 0/1 up/down: 177/-154 (23)
Function old new delta
signal_debug_table - 128 +128
init_signal_sysctls - 33 +33
__pfx_init_signal_sysctls - 16 +16
sysctl_init_bases 85 59 -26
debug_table 128 - -128
Total: Before=21256967, After=21256990, chg +0.00%
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
kernel/signal.c | 23 +++++++++++++++++++++++
kernel/sysctl.c | 14 --------------
2 files changed, 23 insertions(+), 14 deletions(-)
diff --git a/kernel/signal.c b/kernel/signal.c
index 8f6330f0e9ca..5ba4150c01a7 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -45,6 +45,7 @@
#include <linux/posix-timers.h>
#include <linux/cgroup.h>
#include <linux/audit.h>
+#include <linux/sysctl.h>
#define CREATE_TRACE_POINTS
#include <trace/events/signal.h>
@@ -4771,6 +4772,28 @@ static inline void siginfo_buildtime_checks(void)
#endif
}
+#if defined(CONFIG_SYSCTL)
+static struct ctl_table signal_debug_table[] = {
+#ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
+ {
+ .procname = "exception-trace",
+ .data = &show_unhandled_signals,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec
+ },
+#endif
+ { }
+};
+
+static int __init init_signal_sysctls(void)
+{
+ register_sysctl_init("debug", signal_debug_table);
+ return 0;
+}
+early_initcall(init_signal_sysctls);
+#endif /* CONFIG_SYSCTL */
+
void __init signals_init(void)
{
siginfo_buildtime_checks();
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index a7fdb828afb6..43240955dcad 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2331,24 +2331,10 @@ static struct ctl_table vm_table[] = {
{ }
};
-static struct ctl_table debug_table[] = {
-#ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
- {
- .procname = "exception-trace",
- .data = &show_unhandled_signals,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec
- },
-#endif
- { }
-};
-
int __init sysctl_init_bases(void)
{
register_sysctl_init("kernel", kern_table);
register_sysctl_init("vm", vm_table);
- register_sysctl_init("debug", debug_table);
return 0;
}
--
2.39.2On Fri, May 26, 2023 at 03:22:06PM -0700, Luis Chamberlain wrote:
> The show_unhandled_signals sysctl is the only sysctl for debug
> left on kernel/sysctl.c. We've been moving the syctls out from
> kernel/sysctl.c so to help avoid merge conflicts as the shared
> array gets out of hand.
>
> This change incurs simplifies sysctl registration by localizing
> it where it should go for a penalty in size of increasing the
> kernel by 23 bytes, we accept this given recent cleanups have
> actually already saved us 1465 bytes in the prior commits.
>
> ./scripts/bloat-o-meter vmlinux.3-remove-dev-table vmlinux.4-remove-debug-table
> add/remove: 3/1 grow/shrink: 0/1 up/down: 177/-154 (23)
> Function old new delta
> signal_debug_table - 128 +128
> init_signal_sysctls - 33 +33
> __pfx_init_signal_sysctls - 16 +16
> sysctl_init_bases 85 59 -26
> debug_table 128 - -128
> Total: Before=21256967, After=21256990, chg +0.00%
>
> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
> ---
> kernel/signal.c | 23 +++++++++++++++++++++++
> kernel/sysctl.c | 14 --------------
> 2 files changed, 23 insertions(+), 14 deletions(-)
>
> diff --git a/kernel/signal.c b/kernel/signal.c
> index 8f6330f0e9ca..5ba4150c01a7 100644
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -45,6 +45,7 @@
> #include <linux/posix-timers.h>
> #include <linux/cgroup.h>
> #include <linux/audit.h>
> +#include <linux/sysctl.h>
>
> #define CREATE_TRACE_POINTS
> #include <trace/events/signal.h>
> @@ -4771,6 +4772,28 @@ static inline void siginfo_buildtime_checks(void)
> #endif
> }
>
> +#if defined(CONFIG_SYSCTL)
> +static struct ctl_table signal_debug_table[] = {
> +#ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
> + {
> + .procname = "exception-trace",
> + .data = &show_unhandled_signals,
> + .maxlen = sizeof(int),
> + .mode = 0644,
> + .proc_handler = proc_dointvec
> + },
> +#endif
> + { }
> +};
> +
> +static int __init init_signal_sysctls(void)
> +{
> + register_sysctl_init("debug", signal_debug_table);
> + return 0;
> +}
> +early_initcall(init_signal_sysctls);
> +#endif /* CONFIG_SYSCTL */
> +
> void __init signals_init(void)
> {
> siginfo_buildtime_checks();
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index a7fdb828afb6..43240955dcad 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -2331,24 +2331,10 @@ static struct ctl_table vm_table[] = {
> { }
> };
>
> -static struct ctl_table debug_table[] = {
> -#ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
> - {
> - .procname = "exception-trace",
> - .data = &show_unhandled_signals,
> - .maxlen = sizeof(int),
> - .mode = 0644,
> - .proc_handler = proc_dointvec
> - },
> -#endif
> - { }
> -};
> -
> int __init sysctl_init_bases(void)
> {
> register_sysctl_init("kernel", kern_table);
> register_sysctl_init("vm", vm_table);
> - register_sysctl_init("debug", debug_table);
>
> return 0;
> }
> --
> 2.39.2
>
Reviewed-by: Joel Granados <j.granados@samsung.com>
--
Joel Granados
On Fri, May 26, 2023 at 03:22:06PM -0700, Luis Chamberlain wrote:
> The show_unhandled_signals sysctl is the only sysctl for debug
> left on kernel/sysctl.c. We've been moving the syctls out from
> kernel/sysctl.c so to help avoid merge conflicts as the shared
> array gets out of hand.
>
> This change incurs simplifies sysctl registration by localizing
> it where it should go for a penalty in size of increasing the
> kernel by 23 bytes, we accept this given recent cleanups have
> actually already saved us 1465 bytes in the prior commits.
>
> ./scripts/bloat-o-meter vmlinux.3-remove-dev-table vmlinux.4-remove-debug-table
> add/remove: 3/1 grow/shrink: 0/1 up/down: 177/-154 (23)
> Function old new delta
> signal_debug_table - 128 +128
> init_signal_sysctls - 33 +33
> __pfx_init_signal_sysctls - 16 +16
> sysctl_init_bases 85 59 -26
> debug_table 128 - -128
> Total: Before=21256967, After=21256990, chg +0.00%
>
> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
> ---
> kernel/signal.c | 23 +++++++++++++++++++++++
> kernel/sysctl.c | 14 --------------
> 2 files changed, 23 insertions(+), 14 deletions(-)
>
> diff --git a/kernel/signal.c b/kernel/signal.c
> index 8f6330f0e9ca..5ba4150c01a7 100644
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -45,6 +45,7 @@
> #include <linux/posix-timers.h>
> #include <linux/cgroup.h>
> #include <linux/audit.h>
> +#include <linux/sysctl.h>
>
> #define CREATE_TRACE_POINTS
> #include <trace/events/signal.h>
> @@ -4771,6 +4772,28 @@ static inline void siginfo_buildtime_checks(void)
> #endif
> }
>
> +#if defined(CONFIG_SYSCTL)
> +static struct ctl_table signal_debug_table[] = {
> +#ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
> + {
> + .procname = "exception-trace",
> + .data = &show_unhandled_signals,
> + .maxlen = sizeof(int),
> + .mode = 0644,
> + .proc_handler = proc_dointvec
> + },
> +#endif
> + { }
> +};
> +
> +static int __init init_signal_sysctls(void)
> +{
> + register_sysctl_init("debug", signal_debug_table);
> + return 0;
> +}
> +early_initcall(init_signal_sysctls);
> +#endif /* CONFIG_SYSCTL */
> +
> void __init signals_init(void)
> {
> siginfo_buildtime_checks();
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index a7fdb828afb6..43240955dcad 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -2331,24 +2331,10 @@ static struct ctl_table vm_table[] = {
> { }
> };
>
> -static struct ctl_table debug_table[] = {
> -#ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
> - {
> - .procname = "exception-trace",
> - .data = &show_unhandled_signals,
> - .maxlen = sizeof(int),
> - .mode = 0644,
> - .proc_handler = proc_dointvec
> - },
> -#endif
> - { }
> -};
> -
> int __init sysctl_init_bases(void)
> {
> register_sysctl_init("kernel", kern_table);
> register_sysctl_init("vm", vm_table);
> - register_sysctl_init("debug", debug_table);
>
> return 0;
> }
> --
> 2.39.2
>
LGTM
--
Joel Granados
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