[PATCH RFC 1/4] printk: remove BOOT_PRINTK_DELAY config option

[Andrew Murray]

The boot_delay (BOOT_PRINTK_DELAY) kernel parameter and printk_delay sysctl
are two distinct mechanisms for providing similar functionality which add a
delay prior to each printed printk message.

In preparation of combining them into a single configurable feature, let's
first remove the kconfig option BOOT_PRINTK_DELAY.

Signed-off-by: Andrew Murray <amurray@xxxxxxxxxxxxxxxxxxxx>
---
 Documentation/admin-guide/kernel-parameters.txt |  2 +-
 arch/arm/configs/bcm2835_defconfig              |  1 -
 kernel/printk/printk.c                          |  2 +-
 lib/Kconfig.debug                               | 18 ------------------
 4 files changed, 2 insertions(+), 21 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 97007f4f69d4e8f19acaff81c9af8421a09822bf..37b618d176f1c499f457f0d8b5679c29ee7ab177 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -656,7 +656,7 @@ Kernel parameters
 
 	boot_delay=	[KNL,EARLY]
 			Milliseconds to delay each printk during boot.
-			Only works if CONFIG_BOOT_PRINTK_DELAY is enabled,
+			Only works if GENERIC_CALIBRATE_DELAY is enabled,
 			and you may also have to specify "lpj=".  Boot_delay
 			values larger than 10 seconds (10000) are assumed
 			erroneous and ignored.
diff --git a/arch/arm/configs/bcm2835_defconfig b/arch/arm/configs/bcm2835_defconfig
index 4a8ac09843d73280cc42dbbf63fe3cc9f31dacd2..51a1e94d5aa6c22202778082b877a202a6b9c04d 100644
--- a/arch/arm/configs/bcm2835_defconfig
+++ b/arch/arm/configs/bcm2835_defconfig
@@ -174,7 +174,6 @@ CONFIG_NLS_UTF8=y
 CONFIG_DMA_CMA=y
 CONFIG_CMA_SIZE_MBYTES=32
 CONFIG_PRINTK_TIME=y
-CONFIG_BOOT_PRINTK_DELAY=y
 CONFIG_DYNAMIC_DEBUG=y
 CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
 # CONFIG_ENABLE_MUST_CHECK is not set
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 0323149548f6a4dbcdd80029478b809d44de9b62..822fcdff7b21ac00cfa655c3d9b4de2698fcb7d8 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1289,7 +1289,7 @@ static bool suppress_message_printing(int level)
 	return (level >= console_loglevel && !ignore_loglevel);
 }
 
-#ifdef CONFIG_BOOT_PRINTK_DELAY
+#ifdef CONFIG_GENERIC_CALIBRATE_DELAY
 
 static int boot_delay; /* msecs delay after each printk during bootup */
 static unsigned long long loops_per_msec;	/* based on boot_delay */
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 8ff5adcfe1e0a2f13893c92c3b95498fedb83855..fa82d76e7de45e05e5c0d578eaa2e5807bca39d1 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -99,24 +99,6 @@ config MESSAGE_LOGLEVEL_DEFAULT
 	  by default. To change that, use loglevel=<x> in the kernel bootargs,
 	  or pick a different CONSOLE_LOGLEVEL_DEFAULT configuration value.
 
-config BOOT_PRINTK_DELAY
-	bool "Delay each boot printk message by N milliseconds"
-	depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY
-	help
-	  This build option allows you to read kernel boot messages
-	  by inserting a short delay after each one.  The delay is
-	  specified in milliseconds on the kernel command line,
-	  using "boot_delay=N".
-
-	  It is likely that you would also need to use "lpj=M" to preset
-	  the "loops per jiffy" value.
-	  See a previous boot log for the "lpj" value to use for your
-	  system, and then set "lpj=M" before setting "boot_delay=N".
-	  NOTE:  Using this option may adversely affect SMP systems.
-	  I.e., processors other than the first one may not boot up.
-	  BOOT_PRINTK_DELAY also may cause LOCKUP_DETECTOR to detect
-	  what it believes to be lockup conditions.
-
 config DYNAMIC_DEBUG
 	bool "Enable dynamic printk() support"
 	default n

-- 
2.34.1