[PATCH] per-task-delay-accounting: setup

Initialization code related to collection of per-task "delay" statistics which
measure how long it had to wait for cpu, sync block io, swapping etc.  The
collection of statistics and the interface are in other patches.  This patch
sets up the data structures and allows the statistics collection to be
disabled through a kernel boot parameter.

Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 12 insertions, 0 deletions

diff --git a/init/Kconfig b/init/Kconfig
index a5b073a103e7..90498a3e53da 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -158,6 +158,16 @@ config BSD_PROCESS_ACCT_V3
           for processing it. A preliminary version of these tools is available
           at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
 
+config TASK_DELAY_ACCT
+        bool "Enable per-task delay accounting (EXPERIMENTAL)"
+        help
+          Collect information on time spent by a task waiting for system
+          resources like cpu, synchronous block I/O completion and swapping
+          in pages. Such statistics can help in setting a task's priorities
+          relative to other tasks for cpu, io, rss limits etc.
+
+          Say N if unsure.
+
 config SYSCTL
         bool "Sysctl support" if EMBEDDED
         default y
diff --git a/init/main.c b/init/main.c
index 628b8e9e841a..9e8e8c152142 100644
--- a/init/main.c
+++ b/init/main.c
@@ -41,6 +41,7 @@
 #include <linux/cpu.h>
 #include <linux/cpuset.h>
 #include <linux/efi.h>
+#include <linux/delayacct.h>
 #include <linux/unistd.h>
 #include <linux/rmap.h>
 #include <linux/mempolicy.h>
@@ -574,6 +575,7 @@ asmlinkage void __init start_kernel(void)
         proc_root_init();
 #endif
         cpuset_init();
+        delayacct_init();
 
         check_bugs();