Thank you Amol and Phong for your valuable feedback. I have made the changes requested and sent the patch. https://lists.linuxfoundation.org/pipermail/linux-kernel-mentees/2019-November/001055.html Regards, Madhuparna ᐧ On Tue, Nov 5, 2019 at 8:15 PM Paul E. McKenney wrote: > On Tue, Nov 05, 2019 at 08:03:44PM +0530, Amol Grover wrote: > > On Tue, Nov 05, 2019 at 06:04:11AM -0800, Paul E. McKenney wrote: > > > On Tue, Nov 05, 2019 at 08:49:47PM +0700, Phong Tran wrote: > > > > On 10/29/19 3:24 AM, madhuparnabhowmik04@gmail.com wrote: > > > > > From: Madhuparna Bhowmik > > > > > > > > > > This patch converts arrayRCU from txt to rst format. > > > > > arrayRCU.rst is also added in the index.rst file. > > > > > > > > > > Signed-off-by: Madhuparna Bhowmik > > > > > --- > > > > > .../RCU/{arrayRCU.txt => arrayRCU.rst} | 18 > +++++++++++++----- > > > > > Documentation/RCU/index.rst | 1 + > > > > > 2 files changed, 14 insertions(+), 5 deletions(-) > > > > > rename Documentation/RCU/{arrayRCU.txt => arrayRCU.rst} (91%) > > > > > > > > > > diff --git a/Documentation/RCU/arrayRCU.txt > b/Documentation/RCU/arrayRCU.rst > > > > > similarity index 91% > > > > > rename from Documentation/RCU/arrayRCU.txt > > > > > rename to Documentation/RCU/arrayRCU.rst > > > > > index f05a9afb2c39..ed5ae24b196e 100644 > > > > > --- a/Documentation/RCU/arrayRCU.txt > > > > > +++ b/Documentation/RCU/arrayRCU.rst > > > > > @@ -1,5 +1,7 @@ > > > > > -Using RCU to Protect Read-Mostly Arrays > > > > > +.. _array_rcu_doc: > > > > > +Using RCU to Protect Read-Mostly Arrays > > > > > +======================================= > > > > > Although RCU is more commonly used to protect linked lists, it > can > > > > > also be used to protect arrays. Three situations are as follows: > > > > > @@ -26,6 +28,7 @@ described in the following sections. > > > > > > > > It will be better to have the cross reference for each situation. > > > > > > > > Hash Tables > > > > Static Arrays > > > > Resizeable Arrays > > > > > > Madhuparna, could you please put a patch together creating these > > > cross-references and handling Phong's comments below (probably > > > by getting rid of the "." so that the resulting ":" doesn't look > > > strange)? > > > > > > Then I will fold that patch into your original commit in -rcu and > > > add Phong's Tested-by. > > > > > > Thanx, Paul > > > > > > > > Situation 1: Hash Tables > > > > > +------------------------ > > > > > Hash tables are often implemented as an array, where each array > entry > > > > > has a linked-list hash chain. Each hash chain can be protected > by RCU > > > > > @@ -34,6 +37,7 @@ to other array-of-list situations, such as radix > trees. > > > > > Situation 2: Static Arrays > > > > > +-------------------------- > > > > > Static arrays, where the data (rather than a pointer to the > data) is > > > > > located in each array element, and where the array is never > resized, > > > > > @@ -41,11 +45,13 @@ have not been used with RCU. Rik van Riel > recommends using seqlock in > > > > > this situation, which would also have minimal read-side overhead > as long > > > > > as updates are rare. > > > > > -Quick Quiz: Why is it so important that updates be rare when > > > > > - using seqlock? > > > > > +Quick Quiz: > > > > > + Why is it so important that updates be rare when > using seqlock? > > > > > +:ref:`Answer to Quick Quiz ` > > > > > Situation 3: Resizeable Arrays > > > > > +------------------------------ > > > > > Use of RCU for resizeable arrays is demonstrated by the > grow_ary() > > > > > function formerly used by the System V IPC code. The array is > used > > > > > @@ -60,7 +66,7 @@ the remainder of the new, updates the > ids->entries pointer to point to > > > > > the new array, and invokes ipc_rcu_putref() to free up the old > array. > > > > > Note that rcu_assign_pointer() is used to update the > ids->entries pointer, > > > > > which includes any memory barriers required on whatever > architecture > > > > > -you are running on. > > > > > +you are running on.:: > > > > > > > > a redundant ":" in here with html page. > > > > > > > > > > > > > > > > > > > > > static int grow_ary(struct ipc_ids* ids, int newsize) > > > > > { > > > > > @@ -112,7 +118,7 @@ a simple check suffices. The pointer to the > structure corresponding > > > > > to the desired IPC object is placed in "out", with NULL > indicating > > > > > a non-existent entry. After acquiring "out->lock", the > "out->deleted" > > > > > flag indicates whether the IPC object is in the process of being > > > > > -deleted, and, if not, the pointer is returned. > > > > > +deleted, and, if not, the pointer is returned.:: > > > > > > > > same as above > > > > > > > > > > > > Tested-by: Phong Tran > > > > > > > > Regards, > > > > Phong. > > > > > > > > > struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id) > > > > > { > > > > > @@ -144,8 +150,10 @@ deleted, and, if not, the pointer is returned. > > > > > return out; > > > > > } > > > > > +.. _answer_quick_quiz_seqlock: > > > > > Answer to Quick Quiz: > > > > > + Why is it so important that updates be rare when using > seqlock? > > > > > The reason that it is important that updates be rare when > > > > > using seqlock is that frequent updates can livelock > readers. > > > > > diff --git a/Documentation/RCU/index.rst > b/Documentation/RCU/index.rst > > > > > index 5c99185710fa..8d20d44f8fd4 100644 > > > > > --- a/Documentation/RCU/index.rst > > > > > +++ b/Documentation/RCU/index.rst > > > > > @@ -7,6 +7,7 @@ RCU concepts > > > > > .. toctree:: > > > > > :maxdepth: 3 > > > > > + arrayRCU > > > > > rcu > > > > > listRCU > > > > > UP > > > > > > > > _______________________________________________ > > > Linux-kernel-mentees mailing list > > > Linux-kernel-mentees@lists.linuxfoundation.org > > > > https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees > > > > Hey, > > There are a few instances in the document where words are > > emphasized. Example, -not- in the first paragraph. The > > previous emphasis was correct wrt txt format, but this > > could be converted to italicize/bold to keep up with the > > reST format. Other than this and what Phong suggested, > > everything looks good! > > > > Tested-by: Amol Grover > > Thank you, Amol! > > Madhuparna, could you please also include a fix to the "-not-" > text-emphasis issue (and any other occurrences) that Amol located? > > I can then add both Phong's and Amol's Tested-by. > > Thanx, Paul >