>From c8ed9b923cfdc68403998cd154f07f7834ad4edb Mon Sep 17 00:00:00 2001
From: Akira Yokosawa <akiyks@xxxxxxxxx>
Date: Sun, 14 Oct 2018 10:50:24 +0900
Subject: [PATCH 1/7] count: Employ new scheme for inline code snippets
Signed-off-by: Akira Yokosawa <akiyks@xxxxxxxxx>
---
count/count.tex | 89 +++++++++++++++++++++++++++++----------------------------
1 file changed, 46 insertions(+), 43 deletions(-)
diff --git a/count/count.tex b/count/count.tex
index 4d13394..0f35042 100644
--- a/count/count.tex
+++ b/count/count.tex
@@ -2679,30 +2679,33 @@ when updating the counter, and to write-acquire that same reader-writer
lock when checking the counter.
Code for doing I/O might be as follows:
-\vspace{5pt}
-\begin{minipage}[t]{\columnwidth}
-\small
-\begin{verbatim}
- 1 read_lock(&mylock);
- 2 if (removing) {
- 3 read_unlock(&mylock);
- 4 cancel_io();
- 5 } else {
- 6 add_count(1);
- 7 read_unlock(&mylock);
- 8 do_io();
- 9 sub_count(1);
- 10 }
-\end{verbatim}
-\end{minipage}
-\vspace{5pt}
-
-Line~1 read-acquires the lock, and either line~3 or~7 releases it.
-Line~2 checks to see if the device is being removed, and, if so,
-line~3 releases the lock and line~4 cancels the I/O, or takes whatever
+\begin{linelabel}[ln:count:inline:I/O]
+\begin{VerbatimN}[commandchars=\\\[\]]
+read_lock(&mylock); \lnlbl[acq]
+if (removing) { \lnlbl[check]
+ read_unlock(&mylock); \lnlbl[rel1]
+ cancel_io(); \lnlbl[cancel]
+} else {
+ add_count(1); \lnlbl[inc]
+ read_unlock(&mylock); \lnlbl[rel2]
+ do_io(); \lnlbl[do]
+ sub_count(1); \lnlbl[dec]
+}
+\end{VerbatimN}
+\end{linelabel}
+
+\begin{lineref}[ln:count:inline:I/O]
+Line~\lnref{acq} read-acquires the lock, and either
+line~\lnref{rel1} or~\lnref{rel2} releases it.
+Line~\lnref{check} checks to see if the device is being removed, and, if so,
+line~\lnref{rel1} releases the lock and
+line~\lnref{cancel} cancels the I/O, or takes whatever
action is appropriate given that the device is to be removed.
-Otherwise, line~6 increments the access count, line~7 releases the
-lock, line~8 performs the I/O, and line~9 decrements the access count.
+Otherwise, line~\lnref{inc} increments the access count,
+line~\lnref{rel2} releases the
+lock, line~\lnref{do} performs the I/O, and
+line~\lnref{dec} decrements the access count.
+\end{lineref}
\QuickQuiz{}
This is ridiculous!
@@ -2717,27 +2720,27 @@ lock, line~8 performs the I/O, and line~9 decrements the access count.
The code to remove the device might be as follows:
-\vspace{5pt}
-\begin{minipage}[t]{\columnwidth}
-\small
-\begin{verbatim}
- 1 write_lock(&mylock);
- 2 removing = 1;
- 3 sub_count(mybias);
- 4 write_unlock(&mylock);
- 5 while (read_count() != 0) {
- 6 poll(NULL, 0, 1);
- 7 }
- 8 remove_device();
-\end{verbatim}
-\end{minipage}
-\vspace{5pt}
-
-Line~1 write-acquires the lock and line~4 releases it.
-Line~2 notes that the device is being removed, and the loop spanning
-lines~5-7 wait for any I/O operations to complete.
-Finally, line~8 does any additional processing needed to prepare for
+\begin{linelabel}[ln:count:inline:remove]
+\begin{VerbatimN}[commandchars=\\\[\]]
+write_lock(&mylock); \lnlbl[acq]
+removing = 1; \lnlbl[note]
+sub_count(mybias);
+write_unlock(&mylock); \lnlbl[rel]
+while (read_count() != 0) { \lnlbl[loop:b]
+ poll(NULL, 0, 1);
+} \lnlbl[loop:e]
+remove_device(); \lnlbl[remove]
+\end{VerbatimN}
+\end{linelabel}
+
+\begin{lineref}[ln:count:inline:remove]
+Line~\lnref{acq} write-acquires the lock and
+line~\lnref{rel} releases it.
+Line~\lnref{note} notes that the device is being removed, and the loop spanning
+lines~\lnref{loop:b}-\lnref{loop:e} wait for any I/O operations to complete.
+Finally, line~\lnref{remove} does any additional processing needed to prepare for
device removal.
+\end{lineref}
\QuickQuiz{}
What other issues would need to be accounted for in a real system?
--
2.7.4
