[PATCH -perfbook] defer: remove superfluous preposition

[PATCH -perfbook] defer: remove superfluous preposition

[Zhouyi Zhou]

Hi, Paul
 I think preposition 'on' here is superfluous, correct me if I am wrong.
Best Wishes
Zhouyi

---
 defer/rcufundamental.tex | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/defer/rcufundamental.tex b/defer/rcufundamental.tex
index 66f9b70..62f31d0 100644
--- a/defer/rcufundamental.tex
+++ b/defer/rcufundamental.tex
@@ -332,7 +332,7 @@ greater detail in \cref{sec:memorder:RCU}.
 	It might seem strange to have RCU read-side critical sections
 	containing writes, but RCU is just fine with this.
 	This capability is used frequently in the Linux kernel, for
-	example, acquiring a lock on or reference to a data structure.
+	example, acquiring a lock or reference to a data structure.
 	Acquiring either a lock or a reference results in a write
 	to memory, and it is OK to do these within an RCU read-side
 	critical section.
-- 
2.5.0

Re: [PATCH -perfbook] defer: remove superfluous preposition

[Paul E. McKenney]

On Tue, Jul 20, 2021 at 03:17:25PM +0800, Zhouyi Zhou wrote:
> Hi, Paul
>  I think preposition 'on' here is superfluous, correct me if I am wrong.
> Best Wishes
> Zhouyi

The current text is technically grammatically correct, but as you
noticed, rather awkward.  I should rework that sentence and the one
following.  Huh.  Actually, I should rework that entire paragraph.

How about the following?

							Thanx, Paul

------------------------------------------------------------------------

commit 5eb7525e2f7338ea6b817c145a9b4da60e6871d1
Author: Paul E. McKenney <paulmck@kernel.org>
Date:   Tue Jul 20 10:31:03 2021 -0700

    defer/rcufundamental: Wordsmith QQ answer about writes in RCU readers
    
    Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
    Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/defer/rcufundamental.tex b/defer/rcufundamental.tex
index 66f9b702..054512e0 100644
--- a/defer/rcufundamental.tex
+++ b/defer/rcufundamental.tex
@@ -330,12 +330,17 @@ greater detail in \cref{sec:memorder:RCU}.
 	\co{P1()}'s grace period.
 
 	It might seem strange to have RCU read-side critical sections
-	containing writes, but RCU is just fine with this.
-	This capability is used frequently in the Linux kernel, for
-	example, acquiring a lock on or reference to a data structure.
-	Acquiring either a lock or a reference results in a write
-	to memory, and it is OK to do these within an RCU read-side
-	critical section.
+	containing writes, but this capability is not only permitted,
+	but also highly useful.
+	For example, the Linux kernel frequently carries out an
+	RCU-protected traversal of a linked data structure and then
+	acquires a reference to the destination data element.
+	Because this data element must not be freed in the meantime,
+	that element's reference counter must necessarily be incremented
+	within the traversal's RCU read-side critical section.
+	However, that increment entails a write to memory.
+	Therefore, it is a very good thing that memory writes are
+	permitted within RCU read-side critical sections.
 
 	If having writes in RCU read-side critical sections still seems
 	strange, please review

Re: [PATCH -perfbook] defer: remove superfluous preposition

[Zhouyi Zhou]

Thanks Paul for reviewing the patch

On Wed, Jul 21, 2021 at 1:33 AM Paul E. McKenney <paulmck@kernel.org> wrote:
>
> On Tue, Jul 20, 2021 at 03:17:25PM +0800, Zhouyi Zhou wrote:
> > Hi, Paul
> >  I think preposition 'on' here is superfluous, correct me if I am wrong.
> > Best Wishes
> > Zhouyi
>
> The current text is technically grammatically correct, but as you
> noticed, rather awkward.  I should rework that sentence and the one
> following.  Huh.  Actually, I should rework that entire paragraph.
>
> How about the following?
>
>                                                         Thanx, Paul
>
> ------------------------------------------------------------------------
>
> commit 5eb7525e2f7338ea6b817c145a9b4da60e6871d1
> Author: Paul E. McKenney <paulmck@kernel.org>
> Date:   Tue Jul 20 10:31:03 2021 -0700
>
>     defer/rcufundamental: Wordsmith QQ answer about writes in RCU readers
>
>     Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
>     Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
>
> diff --git a/defer/rcufundamental.tex b/defer/rcufundamental.tex
> index 66f9b702..054512e0 100644
> --- a/defer/rcufundamental.tex
> +++ b/defer/rcufundamental.tex
> @@ -330,12 +330,17 @@ greater detail in \cref{sec:memorder:RCU}.
>         \co{P1()}'s grace period.
>
>         It might seem strange to have RCU read-side critical sections
> -       containing writes, but RCU is just fine with this.
> -       This capability is used frequently in the Linux kernel, for
> -       example, acquiring a lock on or reference to a data structure.
> -       Acquiring either a lock or a reference results in a write
> -       to memory, and it is OK to do these within an RCU read-side
> -       critical section.
> +       containing writes, but this capability is not only permitted,
> +       but also highly useful.
> +       For example, the Linux kernel frequently carries out an
> +       RCU-protected traversal of a linked data structure and then
> +       acquires a reference to the destination data element.
> +       Because this data element must not be freed in the meantime,
> +       that element's reference counter must necessarily be incremented
> +       within the traversal's RCU read-side critical section.
> +       However, that increment entails a write to memory.
> +       Therefore, it is a very good thing that memory writes are
> +       permitted within RCU read-side critical sections.
The revised paragraph is easier for me to understand, especially why acquiring
a reference to a data structure entails a write ;-)
>
>         If having writes in RCU read-side critical sections still seems
>         strange, please review
The revised edition looks wonderful, thank you

Thanks again
Zhouyi

Re: [PATCH -perfbook] defer: remove superfluous preposition

[Paul E. McKenney]

On Wed, Jul 21, 2021 at 02:36:30AM +0800, Zhouyi Zhou wrote:
> Thanks Paul for reviewing the patch
> 
> On Wed, Jul 21, 2021 at 1:33 AM Paul E. McKenney <paulmck@kernel.org> wrote:
> >
> > On Tue, Jul 20, 2021 at 03:17:25PM +0800, Zhouyi Zhou wrote:
> > > Hi, Paul
> > >  I think preposition 'on' here is superfluous, correct me if I am wrong.
> > > Best Wishes
> > > Zhouyi
> >
> > The current text is technically grammatically correct, but as you
> > noticed, rather awkward.  I should rework that sentence and the one
> > following.  Huh.  Actually, I should rework that entire paragraph.
> >
> > How about the following?
> >
> >                                                         Thanx, Paul
> >
> > ------------------------------------------------------------------------
> >
> > commit 5eb7525e2f7338ea6b817c145a9b4da60e6871d1
> > Author: Paul E. McKenney <paulmck@kernel.org>
> > Date:   Tue Jul 20 10:31:03 2021 -0700
> >
> >     defer/rcufundamental: Wordsmith QQ answer about writes in RCU readers
> >
> >     Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
> >     Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
> >
> > diff --git a/defer/rcufundamental.tex b/defer/rcufundamental.tex
> > index 66f9b702..054512e0 100644
> > --- a/defer/rcufundamental.tex
> > +++ b/defer/rcufundamental.tex
> > @@ -330,12 +330,17 @@ greater detail in \cref{sec:memorder:RCU}.
> >         \co{P1()}'s grace period.
> >
> >         It might seem strange to have RCU read-side critical sections
> > -       containing writes, but RCU is just fine with this.
> > -       This capability is used frequently in the Linux kernel, for
> > -       example, acquiring a lock on or reference to a data structure.
> > -       Acquiring either a lock or a reference results in a write
> > -       to memory, and it is OK to do these within an RCU read-side
> > -       critical section.
> > +       containing writes, but this capability is not only permitted,
> > +       but also highly useful.
> > +       For example, the Linux kernel frequently carries out an
> > +       RCU-protected traversal of a linked data structure and then
> > +       acquires a reference to the destination data element.
> > +       Because this data element must not be freed in the meantime,
> > +       that element's reference counter must necessarily be incremented
> > +       within the traversal's RCU read-side critical section.
> > +       However, that increment entails a write to memory.
> > +       Therefore, it is a very good thing that memory writes are
> > +       permitted within RCU read-side critical sections.
> The revised paragraph is easier for me to understand, especially why acquiring
> a reference to a data structure entails a write ;-)
> >
> >         If having writes in RCU read-side critical sections still seems
> >         strange, please review
> The revised edition looks wonderful, thank you

Glad you like it, and thank you for pointing me at the original
awkward sentence!

							Thanx, Paul

Re: [PATCH -perfbook] defer: remove superfluous preposition

[Zhouyi Zhou]

On Wed, Jul 21, 2021 at 3:06 AM Paul E. McKenney <paulmck@kernel.org> wrote:
>
> On Wed, Jul 21, 2021 at 02:36:30AM +0800, Zhouyi Zhou wrote:
> > Thanks Paul for reviewing the patch
> >
> > On Wed, Jul 21, 2021 at 1:33 AM Paul E. McKenney <paulmck@kernel.org> wrote:
> > >
> > > On Tue, Jul 20, 2021 at 03:17:25PM +0800, Zhouyi Zhou wrote:
> > > > Hi, Paul
> > > >  I think preposition 'on' here is superfluous, correct me if I am wrong.
> > > > Best Wishes
> > > > Zhouyi
> > >
> > > The current text is technically grammatically correct, but as you
> > > noticed, rather awkward.  I should rework that sentence and the one
> > > following.  Huh.  Actually, I should rework that entire paragraph.
> > >
> > > How about the following?
> > >
> > >                                                         Thanx, Paul
> > >
> > > ------------------------------------------------------------------------
> > >
> > > commit 5eb7525e2f7338ea6b817c145a9b4da60e6871d1
> > > Author: Paul E. McKenney <paulmck@kernel.org>
> > > Date:   Tue Jul 20 10:31:03 2021 -0700
> > >
> > >     defer/rcufundamental: Wordsmith QQ answer about writes in RCU readers
> > >
> > >     Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
> > >     Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
> > >
> > > diff --git a/defer/rcufundamental.tex b/defer/rcufundamental.tex
> > > index 66f9b702..054512e0 100644
> > > --- a/defer/rcufundamental.tex
> > > +++ b/defer/rcufundamental.tex
> > > @@ -330,12 +330,17 @@ greater detail in \cref{sec:memorder:RCU}.
> > >         \co{P1()}'s grace period.
> > >
> > >         It might seem strange to have RCU read-side critical sections
> > > -       containing writes, but RCU is just fine with this.
> > > -       This capability is used frequently in the Linux kernel, for
> > > -       example, acquiring a lock on or reference to a data structure.
> > > -       Acquiring either a lock or a reference results in a write
> > > -       to memory, and it is OK to do these within an RCU read-side
> > > -       critical section.
> > > +       containing writes, but this capability is not only permitted,
> > > +       but also highly useful.
> > > +       For example, the Linux kernel frequently carries out an
> > > +       RCU-protected traversal of a linked data structure and then
> > > +       acquires a reference to the destination data element.
> > > +       Because this data element must not be freed in the meantime,
> > > +       that element's reference counter must necessarily be incremented
> > > +       within the traversal's RCU read-side critical section.
> > > +       However, that increment entails a write to memory.
> > > +       Therefore, it is a very good thing that memory writes are
> > > +       permitted within RCU read-side critical sections.
> > The revised paragraph is easier for me to understand, especially why acquiring
> > a reference to a data structure entails a write ;-)
> > >
> > >         If having writes in RCU read-side critical sections still seems
> > >         strange, please review
> > The revised edition looks wonderful, thank you
>
> Glad you like it, and thank you for pointing me at the original
> awkward sentence!
You are very welcome ;-),   reading the book itself is a
self-improvement process,
To be honest,  by reading the book, I find you are the example worth
following in my career life.
>
>                                                         Thanx, Paul
Best Wishes
Zhouyi