[PATCH] fix hrtimers documentation

[Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>]

Fix hrtimers documentation.

- The word `patch' is used to indicate hrtimers subsystem implementation.
  However this subsystem has already been in ustream kernel, so convert
  them into appropriate phrases.
- Some minor cleanups.

Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>

Index: linux-2.6.21/Documentation/hrtimers/hrtimers.txt
===================================================================
--- linux-2.6.21.orig/Documentation/hrtimers/hrtimers.txt	2007-04-27 12:45:56.000000000 +0900
+++ linux-2.6.21/Documentation/hrtimers/hrtimers.txt	2007-04-27 13:24:22.000000000 +0900
@@ -1,8 +1,9 @@
 
 hrtimers - subsystem for high-resolution kernel timers
-----------------------------------------------------
+------------------------------------------------------
 
-This patch introduces a new subsystem for high-resolution kernel timers.
+This document describes hrtimers, a new subsystem for high-resolution
+kernel timers.
 
 One might ask the question: we already have a timer subsystem
 (kernel/timers.c), why do we need two timer subsystems? After a lot of
@@ -78,7 +79,7 @@ from 250 Hz to 100 HZ (or even smaller).
 hrtimer subsystem implementation details
 ----------------------------------------
 
-the basic design considerations were:
+The basic design considerations were:
 
 - simplicity
 
@@ -87,7 +88,7 @@ the basic design considerations were:
 
 - simplification of existing, timing related kernel code
 
-another basic requirement was the immediate enqueueing and ordering of
+Another basic requirement was the immediate enqueueing and ordering of
 timers at activation time. After looking at several possible solutions
 such as radix trees and hashes, we chose the red black tree as the basic
 data structure. Rbtrees are available as a library in the kernel and are
@@ -138,23 +139,22 @@ details.)
 hrtimers - rounding of timer values
 -----------------------------------
 
-the hrtimer code will round timer events to lower-resolution clocks
+The hrtimer code will round timer events to lower-resolution clocks
 because it has to. Otherwise it will do no artificial rounding at all.
 
-one question is, what resolution value should be returned to the user by
+One question is, what resolution value should be returned to the user by
 the clock_getres() interface. This will return whatever real resolution
 a given clock has - be it low-res, high-res, or artificially-low-res.
 
 hrtimers - testing and verification
-----------------------------------
+-----------------------------------
 
-We used the high-resolution clock subsystem ontop of hrtimers to verify
+We used the high-resolution clock subsystem on top of hrtimers to verify
 the hrtimer implementation details in praxis, and we also ran the posix
 timer tests in order to ensure specification compliance. We also ran
 tests on low-resolution clocks.
 
-The hrtimer patch converts the following kernel functionality to use
-hrtimers:
+hrtimers converts the following kernel functionality to use it:
 
  - nanosleep
  - itimers