[PATCH] toolsoftrade: Fix code listing 4.22 in Chapter 4

[PATCH] toolsoftrade: Fix code listing 4.22 in Chapter 4

[Slavomir Kaslev]

Code listing 4.22 is broken since the READ_ONCE() macro takes a rvalue and the
expression parenthesis are unbalanced. This patch fixes it.

Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
 toolsoftrade/toolsoftrade.tex | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/toolsoftrade/toolsoftrade.tex b/toolsoftrade/toolsoftrade.tex
index 41605a33..4e0764d0 100644
--- a/toolsoftrade/toolsoftrade.tex
+++ b/toolsoftrade/toolsoftrade.tex
@@ -2111,7 +2111,7 @@ Listing~\ref{lst:toolsoftrade:Avoiding Danger, 2018 Style}.
 \begin{listing}[tbp]
 \begin{linelabel}[ln:toolsoftrade:Preventing Load Fusing]
 \begin{VerbatimL}[commandchars=\\\{\}]
-while (!READ_ONCE((!need_to_stop))
+while (!READ_ONCE(need_to_stop))
 	do_something_quickly();
 \end{VerbatimL}
 \end{linelabel}
-- 
2.19.1

Re: [PATCH] toolsoftrade: Fix code listing 4.22 in Chapter 4

[Steven Rostedt]

On Tue, 19 Mar 2019 16:59:27 +0200
Slavomir Kaslev <kaslevs@vmware.com> wrote:

> Code listing 4.22 is broken since the READ_ONCE() macro takes a rvalue and the
> expression parenthesis are unbalanced. This patch fixes it.
> 
> Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
> ---
>  toolsoftrade/toolsoftrade.tex | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/toolsoftrade/toolsoftrade.tex b/toolsoftrade/toolsoftrade.tex
> index 41605a33..4e0764d0 100644
> --- a/toolsoftrade/toolsoftrade.tex
> +++ b/toolsoftrade/toolsoftrade.tex
> @@ -2111,7 +2111,7 @@ Listing~\ref{lst:toolsoftrade:Avoiding Danger, 2018 Style}.
>  \begin{listing}[tbp]
>  \begin{linelabel}[ln:toolsoftrade:Preventing Load Fusing]
>  \begin{VerbatimL}[commandchars=\\\{\}]
> -while (!READ_ONCE((!need_to_stop))
> +while (!READ_ONCE(need_to_stop))

But doesn't this change the logic?

I'm guessing that the double "!" was wrong too.

-- Steve


>  	do_something_quickly();
>  \end{VerbatimL}
>  \end{linelabel}

Re: [PATCH] toolsoftrade: Fix code listing 4.22 in Chapter 4

[Paul E. McKenney]

On Tue, Mar 19, 2019 at 04:59:27PM +0200, Slavomir Kaslev wrote:
> Code listing 4.22 is broken since the READ_ONCE() macro takes a rvalue and the
> expression parenthesis are unbalanced. This patch fixes it.
> 
> Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>

Good eyes, thank you!  Queued and pushed.

							Thanx, Paul

> ---
>  toolsoftrade/toolsoftrade.tex | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/toolsoftrade/toolsoftrade.tex b/toolsoftrade/toolsoftrade.tex
> index 41605a33..4e0764d0 100644
> --- a/toolsoftrade/toolsoftrade.tex
> +++ b/toolsoftrade/toolsoftrade.tex
> @@ -2111,7 +2111,7 @@ Listing~\ref{lst:toolsoftrade:Avoiding Danger, 2018 Style}.
>  \begin{listing}[tbp]
>  \begin{linelabel}[ln:toolsoftrade:Preventing Load Fusing]
>  \begin{VerbatimL}[commandchars=\\\{\}]
> -while (!READ_ONCE((!need_to_stop))
> +while (!READ_ONCE(need_to_stop))
>  	do_something_quickly();
>  \end{VerbatimL}
>  \end{linelabel}
> -- 
> 2.19.1
> 

Re: [PATCH] toolsoftrade: Fix code listing 4.22 in Chapter 4

[Paul E. McKenney]

On Tue, Mar 19, 2019 at 11:33:05AM -0400, Steven Rostedt wrote:
> On Tue, 19 Mar 2019 16:59:27 +0200
> Slavomir Kaslev <kaslevs@vmware.com> wrote:
> 
> > Code listing 4.22 is broken since the READ_ONCE() macro takes a rvalue and the
> > expression parenthesis are unbalanced. This patch fixes it.
> > 
> > Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
> > ---
> >  toolsoftrade/toolsoftrade.tex | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/toolsoftrade/toolsoftrade.tex b/toolsoftrade/toolsoftrade.tex
> > index 41605a33..4e0764d0 100644
> > --- a/toolsoftrade/toolsoftrade.tex
> > +++ b/toolsoftrade/toolsoftrade.tex
> > @@ -2111,7 +2111,7 @@ Listing~\ref{lst:toolsoftrade:Avoiding Danger, 2018 Style}.
> >  \begin{listing}[tbp]
> >  \begin{linelabel}[ln:toolsoftrade:Preventing Load Fusing]
> >  \begin{VerbatimL}[commandchars=\\\{\}]
> > -while (!READ_ONCE((!need_to_stop))
> > +while (!READ_ONCE(need_to_stop))
> 
> But doesn't this change the logic?

It does.

> I'm guessing that the double "!" was wrong too.

And it was.  In converting Listing 4.16 to 4.24 (your listing numbers
may vary), I added the READ_ONCE(), but missed removing the extra "!".
Or I added the READ_ONCE() in the wrong place, your choice.  ;-)

							Thanx, Paul

> -- Steve
> 
> 
> >  	do_something_quickly();
> >  \end{VerbatimL}
> >  \end{linelabel}
>