[PATCH 1/3] printk: use CONFIG_CONSOLE_LOGLEVEL_* directly

* [PATCH 1/3] printk: use CONFIG_CONSOLE_LOGLEVEL_* directly
@ 2021-02-02  7:02 ` Masahiro Yamada
  0 siblings, 0 replies; 26+ messages in thread
From: Masahiro Yamada @ 2021-02-02  7:02 UTC (permalink / raw)
  To: linux-kernel, Petr Mladek, Sergey Senozhatsky, Steven Rostedt,
	John Ogness
  Cc: Masahiro Yamada, Andy Shevchenko, Ard Biesheuvel,
	Borislav Petkov, Darren Hart, Dimitri Sivanich,
	Greg Kroah-Hartman, H. Peter Anvin, Ingo Molnar, Jiri Slaby,
	Mike Travis, Peter Jones, Russ Anderson, Steve Wahl,
	Thomas Gleixner, dri-devel, linux-efi, linux-fbdev,
	platform-driver-x86, x86

CONSOLE_LOGLEVEL_DEFAULT is nothing more than a shorthand of
CONFIG_CONSOLE_LOGLEVEL_DEFAULT.

When you change CONFIG_CONSOLE_LOGLEVEL_DEFAULT from Kconfig, almost
all objects are rebuilt because CONFIG_CONSOLE_LOGLEVEL_DEFAULT is
used in <linux/printk.h>, which is included from most of source files.

In fact, there are only 4 users of CONSOLE_LOGLEVEL_DEFAULT:

  arch/x86/platform/uv/uv_nmi.c
  drivers/firmware/efi/libstub/efi-stub-helper.c
  drivers/tty/sysrq.c
  kernel/printk/printk.c

So, when you change CONFIG_CONSOLE_LOGLEVEL_DEFAULT and rebuild the
kernel, it is enough to recompile those 4 files.

Remove the CONSOLE_LOGLEVEL_DEFAULT definition from <linux/printk.h>,
and use CONFIG_CONSOLE_LOGLEVEL_DEFAULT directly.

With this, the build system will rebuild the minimal number of objects.

Steps to confirm it:

  [1] Do the full build
  [2] Change CONFIG_CONSOLE_LOGLEVEL_DEFAULT from 'make menuconfig' etc.
  [3] Rebuild

  $ make
    SYNC    include/config/auto.conf
    CALL    scripts/checksyscalls.sh
    CALL    scripts/atomic/check-atomics.sh
    DESCEND  objtool
    CHK     include/generated/compile.h
    CC      kernel/printk/printk.o
    AR      kernel/printk/built-in.a
    AR      kernel/built-in.a
    CC      drivers/tty/sysrq.o
    AR      drivers/tty/built-in.a
    CC      drivers/firmware/efi/libstub/efi-stub-helper.o
    STUBCPY drivers/firmware/efi/libstub/efi-stub-helper.stub.o
    AR      drivers/firmware/efi/libstub/lib.a
    AR      drivers/built-in.a
    GEN     .version
    CHK     include/generated/compile.h
    UPD     include/generated/compile.h
    CC      init/version.o
    AR      init/built-in.a
    LD      vmlinux.o
    ...

For the same reason, do likewise for CONSOLE_LOGLEVEL_QUIET and
MESSAGE_LOGLEVEL_DEFAULT.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 arch/x86/platform/uv/uv_nmi.c                  |  2 +-
 drivers/firmware/efi/libstub/efi-stub-helper.c |  6 +++---
 drivers/tty/sysrq.c                            |  4 ++--
 drivers/video/fbdev/core/fbcon.c               |  2 +-
 drivers/video/fbdev/efifb.c                    |  2 +-
 include/linux/printk.h                         | 10 ----------
 init/main.c                                    |  2 +-
 kernel/printk/printk.c                         |  6 +++---
 8 files changed, 12 insertions(+), 22 deletions(-)

diff --git a/arch/x86/platform/uv/uv_nmi.c b/arch/x86/platform/uv/uv_nmi.c
index eafc530c8767..4751299c7416 100644
--- a/arch/x86/platform/uv/uv_nmi.c
+++ b/arch/x86/platform/uv/uv_nmi.c
@@ -100,7 +100,7 @@ static cpumask_var_t uv_nmi_cpu_mask;
  * Default is all stack dumps go to the console and buffer.
  * Lower level to send to log buffer only.
  */
-static int uv_nmi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
+static int uv_nmi_loglevel = CONFIG_CONSOLE_LOGLEVEL_DEFAULT;
 module_param_named(dump_loglevel, uv_nmi_loglevel, int, 0644);
 
 /*
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index aa8da0a49829..3e8d8f706589 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -12,7 +12,7 @@
 #include <linux/ctype.h>
 #include <linux/efi.h>
 #include <linux/kernel.h>
-#include <linux/printk.h> /* For CONSOLE_LOGLEVEL_* */
+#include <linux/printk.h> /* For CONSOLE_LOGLEVEL_DEBUG */
 #include <asm/efi.h>
 #include <asm/setup.h>
 
@@ -21,7 +21,7 @@
 bool efi_nochunk;
 bool efi_nokaslr = !IS_ENABLED(CONFIG_RANDOMIZE_BASE);
 bool efi_noinitrd;
-int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
+int efi_loglevel = CONFIG_CONSOLE_LOGLEVEL_DEFAULT;
 bool efi_novamap;
 
 static bool efi_nosoftreserve;
@@ -213,7 +213,7 @@ efi_status_t efi_parse_options(char const *cmdline)
 		if (!strcmp(param, "nokaslr")) {
 			efi_nokaslr = true;
 		} else if (!strcmp(param, "quiet")) {
-			efi_loglevel = CONSOLE_LOGLEVEL_QUIET;
+			efi_loglevel = CONFIG_CONSOLE_LOGLEVEL_QUIET;
 		} else if (!strcmp(param, "noinitrd")) {
 			efi_noinitrd = true;
 		} else if (!strcmp(param, "efi") && val) {
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 959f9e121cc6..e0ae7793155e 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -103,7 +103,7 @@ static void sysrq_handle_loglevel(int key)
 	int i;
 
 	i = key - '0';
-	console_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
+	console_loglevel = CONFIG_CONSOLE_LOGLEVEL_DEFAULT;
 	pr_info("Loglevel set to %d\n", i);
 	console_loglevel = i;
 }
@@ -584,7 +584,7 @@ void __handle_sysrq(int key, bool check_mask)
 	 * routing in the consumers of /proc/kmsg.
 	 */
 	orig_log_level = console_loglevel;
-	console_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
+	console_loglevel = CONFIG_CONSOLE_LOGLEVEL_DEFAULT;
 
         op_p = __sysrq_get_key_op(key);
         if (op_p) {
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index bf61598bf1c3..75b97268663f 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -1043,7 +1043,7 @@ static void fbcon_init(struct vc_data *vc, int init)
 
 	info = registered_fb[con2fb_map[vc->vc_num]];
 
-	if (logo_shown < 0 && console_loglevel <= CONSOLE_LOGLEVEL_QUIET)
+	if (logo_shown < 0 && console_loglevel <= CONFIG_CONSOLE_LOGLEVEL_QUIET)
 		logo_shown = FBCON_LOGO_DONTSHOW;
 
 	if (vc != svc || logo_shown == FBCON_LOGO_DONTSHOW ||
diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
index e57c00824965..dfb234a0a59d 100644
--- a/drivers/video/fbdev/efifb.c
+++ b/drivers/video/fbdev/efifb.c
@@ -160,7 +160,7 @@ static void efifb_show_boot_graphics(struct fb_info *info)
 	}
 
 	/* Avoid flashing the logo if we're going to print std probe messages */
-	if (console_loglevel > CONSOLE_LOGLEVEL_QUIET)
+	if (console_loglevel > CONFIG_CONSOLE_LOGLEVEL_QUIET)
 		return;
 
 	/* bgrt_tab.status is unreliable, so we don't check it */
diff --git a/include/linux/printk.h b/include/linux/printk.h
index fe7eb2351610..fd34b3aa2f90 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -46,22 +46,12 @@ static inline const char *printk_skip_headers(const char *buffer)
 
 #define CONSOLE_EXT_LOG_MAX	8192
 
-/* printk's without a loglevel use this.. */
-#define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
-
 /* We show everything that is MORE important than this.. */
 #define CONSOLE_LOGLEVEL_SILENT  0 /* Mum's the word */
 #define CONSOLE_LOGLEVEL_MIN	 1 /* Minimum loglevel we let people use */
 #define CONSOLE_LOGLEVEL_DEBUG	10 /* issue debug messages */
 #define CONSOLE_LOGLEVEL_MOTORMOUTH 15	/* You can't shut this one up */
 
-/*
- * Default used to be hard-coded at 7, quiet used to be hardcoded at 4,
- * we're now allowing both to be set from kernel config.
- */
-#define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT
-#define CONSOLE_LOGLEVEL_QUIET	 CONFIG_CONSOLE_LOGLEVEL_QUIET
-
 extern int console_printk[];
 
 #define console_loglevel (console_printk[0])
diff --git a/init/main.c b/init/main.c
index c68d784376ca..4dfcbf7f24c6 100644
--- a/init/main.c
+++ b/init/main.c
@@ -236,7 +236,7 @@ static int __init debug_kernel(char *str)
 
 static int __init quiet_kernel(char *str)
 {
-	console_loglevel = CONSOLE_LOGLEVEL_QUIET;
+	console_loglevel = CONFIG_CONSOLE_LOGLEVEL_QUIET;
 	return 0;
 }
 
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 5a95c688621f..92b93340905c 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -61,10 +61,10 @@
 #include "internal.h"
 
 int console_printk[4] = {
-	CONSOLE_LOGLEVEL_DEFAULT,	/* console_loglevel */
-	MESSAGE_LOGLEVEL_DEFAULT,	/* default_message_loglevel */
+	CONFIG_CONSOLE_LOGLEVEL_DEFAULT,	/* console_loglevel */
+	CONFIG_MESSAGE_LOGLEVEL_DEFAULT,	/* default_message_loglevel */
 	CONSOLE_LOGLEVEL_MIN,		/* minimum_console_loglevel */
-	CONSOLE_LOGLEVEL_DEFAULT,	/* default_console_loglevel */
+	CONFIG_CONSOLE_LOGLEVEL_DEFAULT,	/* default_console_loglevel */
 };
 EXPORT_SYMBOL_GPL(console_printk);
 
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 26+ messages in thread