Merge tag 'printk-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Allow to sort mixed lines by an extra information about the caller

 - Remove no longer used LOG_PREFIX.

 - Some clean up and documentation update.

* tag 'printk-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  printk/docs: Add extra integer types to printk-formats
  printk: Remove no longer used LOG_PREFIX.
  lib/vsprintf: Remove %pCr remnant in comment
  printk: Pass caller information to log_store().
  printk: Add caller information to printk() output.

1 files changed, 17 insertions, 0 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e718487c97c3..91ed81250fb3 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -17,6 +17,23 @@ config PRINTK_TIME
 	  The behavior is also controlled by the kernel command line
 	  parameter printk.time=1. See Documentation/admin-guide/kernel-parameters.rst
 
+config PRINTK_CALLER
+	bool "Show caller information on printks"
+	depends on PRINTK
+	help
+	  Selecting this option causes printk() to add a caller "thread id" (if
+	  in task context) or a caller "processor id" (if not in task context)
+	  to every message.
+
+	  This option is intended for environments where multiple threads
+	  concurrently call printk() for many times, for it is difficult to
+	  interpret without knowing where these lines (or sometimes individual
+	  line which was divided into multiple lines due to race) came from.
+
+	  Since toggling after boot makes the code racy, currently there is
+	  no option to enable/disable at the kernel command line parameter or
+	  sysfs interface.
+
 config CONSOLE_LOGLEVEL_DEFAULT
 	int "Default console loglevel (1-15)"
 	range 1 15