Merge branch 'akpm' (patchbomb from Andrew Morton)

Merge incoming from Andrew Morton:
 - Various misc things.
 - arch/sh updates.
 - Part of ocfs2.  Review is slow.
 - Slab updates.
 - Most of -mm.
 - printk updates.
 - lib/ updates.
 - checkpatch updates.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (226 commits)
  checkpatch: update $declaration_macros, add uninitialized_var
  checkpatch: warn on missing spaces in broken up quoted
  checkpatch: fix false positives for --strict "space after cast" test
  checkpatch: fix false positive MISSING_BREAK warnings with --file
  checkpatch: add test for native c90 types in unusual order
  checkpatch: add signed generic types
  checkpatch: add short int to c variable types
  checkpatch: add for_each tests to indentation and brace tests
  checkpatch: fix brace style misuses of else and while
  checkpatch: add --fix option for a couple OPEN_BRACE misuses
  checkpatch: use the correct indentation for which()
  checkpatch: add fix_insert_line and fix_delete_line helpers
  checkpatch: add ability to insert and delete lines to patch/file
  checkpatch: add an index variable for fixed lines
  checkpatch: warn on break after goto or return with same tab indentation
  checkpatch: emit a warning on file add/move/delete
  checkpatch: add test for commit id formatting style in commit log
  checkpatch: emit fewer kmalloc_array/kcalloc conversion warnings
  checkpatch: improve "no space after cast" test
  checkpatch: allow multiple const * types
  ...

1 files changed, 42 insertions, 4 deletions

diff --git a/init/Kconfig b/init/Kconfig
index 41066e49e880..a291b7ef4738 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -807,15 +807,53 @@ config LOG_BUF_SHIFT
 	range 12 21
 	default 17
 	help
-	  Select kernel log buffer size as a power of 2.
+	  Select the minimal kernel log buffer size as a power of 2.
+	  The final size is affected by LOG_CPU_MAX_BUF_SHIFT config
+	  parameter, see below. Any higher size also might be forced
+	  by "log_buf_len" boot parameter.
+
 	  Examples:
-	  	     17 => 128 KB
+		     17 => 128 KB
 		     16 => 64 KB
-	             15 => 32 KB
-	             14 => 16 KB
+		     15 => 32 KB
+		     14 => 16 KB
 		     13 =>  8 KB
 		     12 =>  4 KB
 
+config LOG_CPU_MAX_BUF_SHIFT
+	int "CPU kernel log buffer size contribution (13 => 8 KB, 17 => 128KB)"
+	range 0 21
+	default 12 if !BASE_SMALL
+	default 0 if BASE_SMALL
+	help
+	  This option allows to increase the default ring buffer size
+	  according to the number of CPUs. The value defines the contribution
+	  of each CPU as a power of 2. The used space is typically only few
+	  lines however it might be much more when problems are reported,
+	  e.g. backtraces.
+
+	  The increased size means that a new buffer has to be allocated and
+	  the original static one is unused. It makes sense only on systems
+	  with more CPUs. Therefore this value is used only when the sum of
+	  contributions is greater than the half of the default kernel ring
+	  buffer as defined by LOG_BUF_SHIFT. The default values are set
+	  so that more than 64 CPUs are needed to trigger the allocation.
+
+	  Also this option is ignored when "log_buf_len" kernel parameter is
+	  used as it forces an exact (power of two) size of the ring buffer.
+
+	  The number of possible CPUs is used for this computation ignoring
+	  hotplugging making the compuation optimal for the the worst case
+	  scenerio while allowing a simple algorithm to be used from bootup.
+
+	  Examples shift values and their meaning:
+		     17 => 128 KB for each CPU
+		     16 =>  64 KB for each CPU
+		     15 =>  32 KB for each CPU
+		     14 =>  16 KB for each CPU
+		     13 =>   8 KB for each CPU
+		     12 =>   4 KB for each CPU
+
 #
 # Architectures with an unreliable sched_clock() should select this:
 #