From mboxrd@z Thu Jan 1 00:00:00 1970
Return-Path: <dev-bounces@dpdk.org>
Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124])
by inbox.dpdk.org (Postfix) with ESMTP id 42F7B43B57;
Tue, 20 Feb 2024 19:59:11 +0100 (CET)
Received: from mails.dpdk.org (localhost [127.0.0.1])
by mails.dpdk.org (Postfix) with ESMTP id CADE4402A7;
Tue, 20 Feb 2024 19:59:10 +0100 (CET)
Received: from mail-ot1-f50.google.com (mail-ot1-f50.google.com
[209.85.210.50]) by mails.dpdk.org (Postfix) with ESMTP id F0DA340289
for <dev@dpdk.org>; Tue, 20 Feb 2024 19:59:09 +0100 (CET)
Received: by mail-ot1-f50.google.com with SMTP id
46e09a7af769-6e445b4f80bso2094431a34.0
for <dev@dpdk.org>; Tue, 20 Feb 2024 10:59:09 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=gmail.com; s=20230601; t=1708455549; x=1709060349; darn=dpdk.org;
h=cc:to:subject:message-id:date:from:in-reply-to:references
:mime-version:from:to:cc:subject:date:message-id:reply-to;
bh=zFgxXztjHRXaDJvppeWcXtxLWJxv0yLykkKZjqVvlQ0=;
b=Sm8piTwTh7PAHgCmJtRxv/BVAurEVPpH3209po2DLzxK64qLo+g6mMQYpx31Wix3l6
GdpwwvFXHOaznvo31a9bu1rKgXS2w080gmcXcfHemJlXlxpY6yJN0n4SrIzSqr8gICuh
p+2d56dOJXqhTe0x9MeUb1uiAJNQoXefgnfJotNLPmilCIDWocv9zK+Kic/X9g9IEuuV
QAdhuHz9umeTOYVuO3ctTIkU4zmETtibWpBlV9KO/Te8T6ZZo3/fx4dkKleLWSccsoJa
NSlfPmmlyhyNWRFKSyjA6c4JOPYEFRQj6KcRrvm/rQ7y6nq1TxUgucCtpc1LdEI9nbve
M5/Q==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=1e100.net; s=20230601; t=1708455549; x=1709060349;
h=cc:to:subject:message-id:date:from:in-reply-to:references
:mime-version:x-gm-message-state:from:to:cc:subject:date:message-id
:reply-to;
bh=zFgxXztjHRXaDJvppeWcXtxLWJxv0yLykkKZjqVvlQ0=;
b=fv/E/Jsx6LGXLIMKb5dy63+GQaLVwoSC9MPQ3qRhJmps6m7GCL5uXyaXPCuar8R5UO
6QBy6mULpk/2rUMDZgOLXJ8+Df2i+b9PwcTX/DvQjR6N2rIuBa5jgF+xouWMX8azsb+n
kByXw3oRTKBpHHhNTzvl6va7jEwXum+zDEz7VHNK2NzoVf5zIa8l6N8C6O056PCua0S/
fsjwOLVyW6MQ7Yk1tKgPH4cITkU3hRLsw+RQnIRC3Yayp3L5wCR5WMv6vgHoSEzfHuFE
pHYTot6GvrZZxmzm74qsC0tKRXgaRhr6gpgcXgIxfwf24pCJ+fDCT8MfET6h1HD8IEjc
xnZg==
X-Forwarded-Encrypted: i=1;
AJvYcCVSBxq0LRXINFlg99yFYGs/BUF6PbB6neb/KdS2FcvbRNbXRet5F/BfJkSz7jz0qD12UXBxds8W77hBL6U=
X-Gm-Message-State: AOJu0YwDFYEbXHFzeeoTHV+bRhBfeayRyc4snakIaVaw2ySybnvFKzqW
/VYlLsMcB8SFw8MIlI5PdMrMn0GP55SEh0ksjQuXUat/ogYnCLKt+vw1Wj2ijVZhp2UhCfc5rpW
NoC0QRbDMCTLxkdZWJY0yxoreCaE=
X-Google-Smtp-Source: AGHT+IGcO36Bn4r/f7ccopLBxK7cKn70yuToo2uwGnd2rYOayFaP8pDy2FzhJtta2YRyeY6d++Y0jCfQkUpmPLLhJgg=
X-Received: by 2002:a05:6870:659f:b0:21e:dd7a:2d3e with SMTP id
fp31-20020a056870659f00b0021edd7a2d3emr7199192oab.22.1708455547798; Tue, 20
Feb 2024 10:59:07 -0800 (PST)
MIME-Version: 1.0
References: <20240207153340.34146-1-aomeryamac@gmail.com>
<cc8ac134-3c87-4f4e-9b21-261dad19b740@intel.com>
<CA+sj1i-HXEt6jGLyUEbO8oj46Q215DPSFvFo1rZwivW1kJDJ=g@mail.gmail.com>
<4CC50196-1F8F-40E2-8280-261783FDCFC8@arm.com>
In-Reply-To: <4CC50196-1F8F-40E2-8280-261783FDCFC8@arm.com>
From: =?UTF-8?B?QWJkdWxsYWggw5ZtZXIgWWFtYcOn?= <aomeryamac@gmail.com>
Date: Tue, 20 Feb 2024 21:58:57 +0300
Message-ID: <CA+sj1i-LverDff3YKOjZ-52NNoUkwQqG2yCCxxPM4CjU0d135w@mail.gmail.com>
Subject: Re: [PATCH] lib/hash,lib/rcu: feature hidden key count in hash
To: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
Cc: "Medvedkin, Vladimir" <vladimir.medvedkin@intel.com>,
"dev@dpdk.org" <dev@dpdk.org>,
Yipeng Wang <yipeng1.wang@intel.com>, Sameh Gobriel <sameh.gobriel@intel.com>,
Bruce Richardson <bruce.richardson@intel.com>,
"thomas@monjalon.net" <thomas@monjalon.net>, nd <nd@arm.com>
Content-Type: multipart/alternative; boundary="0000000000000a8c1a0611d4ce10"
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/dev>,
<mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/dev>,
<mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
--0000000000000a8c1a0611d4ce10
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
I appreciate that you gave me suggestions and comments. I will make changes
according to all your recommendations, but before that, I want to make
everyone's minds clear. Then, I will apply modifications.
On Tue, Feb 20, 2024 at 2:35=E2=80=AFAM Honnappa Nagarahalli <
Honnappa.Nagarahalli@arm.com> wrote:
>
>
> > On Feb 19, 2024, at 3:28=E2=80=AFPM, Abdullah =C3=96mer Yama=C3=A7 <aom=
eryamac@gmail.com>
> wrote:
> >
> > Hello,
> >
> > Let me explain a use case;
> >
> > I have a hash table whose key value is IP addresses, and data (let's sa=
y
> the username of the IP) is related to the IP address. The key point is
> matching these data with flows. Flows are dynamic, and this hash table is
> dynamic, as well; both can change anytime. For example, when a flow start=
s,
> we look up the hash table with the corresponding IP and retrieve the
> username. We need to hold this username until the flow terminates, althou=
gh
> we removed this IP key from the hash table (multithread). That's why we
> have RCU and defer queue is necessary for high performance. In my
> application, I need to know the number of IP-username entries. These
> numbers can be calculated by rte_hash_count - defer queue size.
> The entries in the defer queue are not reclaimed (there is a probability
> that all of them can be reclaimed) and hence they are not available for
> allocation. So, rte_hash_count - defer queue size might not give you the
> correct number you are expecting.
>
> Currently, there is no API in hash library that forces a reclaim. Does it
> makes sense to have an API that just does the reclaim (and returns the
> number of entries pending in the defer queue)? A call to rte_hash_count
> should provide the exact count you are looking for.
You are right; no API in the hash library forces a reclaim. In my
application, I periodically call rte_count to retrieve hash size, and this
data is shown in my GUI. So that means I need to call regularly reclaim. I
am trying to figure out which is better, calling reclaim or retrieving the
defer queue size. Any comment about this?
> >
> > I think if you need a non-blocking and multithreaded hash table, an
> RCU-enabled hash table is necessary. Also, this API is necessary if you
> need to get the actual matchable size.
> >
> >
> >
> >
> >
> > On Mon, Feb 19, 2024 at 8:36=E2=80=AFPM Medvedkin, Vladimir <
> vladimir.medvedkin@intel.com> wrote:
> > Hi Abdullah,
> >
> > Could you please tell more about use cases where this API may be useful=
?
> >
> > >a new API to get the hidden key count in the hash table if the rcu qsb=
r
> is enabled
> >
> > Here in commit message and down below in doxygen comments, I think this
> > statement should be more specific because rcu can be created with
> > RTE_HASH_QSBR_MODE_SYNC mode i.e. without defer queue.
> >
> > Also, new API must be reflected in release notes
> >
> > On 07/02/2024 15:33, Abdullah =C3=96mer Yama=C3=A7 wrote:
> > > This patch introduce a new API to get the hidden key count in the has=
h
> > > table if the rcu qsbr is enabled. When using rte_hash_count with rcu
> > > qsbr enabled, it will return the number of elements that are not in t=
he
> > > free queue. Unless rte_rcu_qsbr_dq_reclaim is called, the number of
> > > elements in the defer queue will not be counted and freed. Therefore =
I
> > > added a new API to get the number of hidden (defer queue) elements
> > > in the hash table. Then the user can calculate the total number of
> > > elements that are available in the hash table.
> > >
> > > Signed-off-by: Abdullah =C3=96mer Yama=C3=A7 <aomeryamac@gmail.com>
> > >
> > > ---
> > > Cc: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> > > Cc: Yipeng Wang <yipeng1.wang@intel.com>
> > > Cc: Sameh Gobriel <sameh.gobriel@intel.com>
> > > Cc: Bruce Richardson <bruce.richardson@intel.com>
> > > Cc: Vladimir Medvedkin <vladimir.medvedkin@intel.com>
> > > ---
> > > lib/hash/rte_cuckoo_hash.c | 9 +++++++++
> > > lib/hash/rte_hash.h | 13 +++++++++++++
> > > lib/hash/version.map | 1 +
> > > lib/rcu/rte_rcu_qsbr.c | 8 ++++++++
> > > lib/rcu/rte_rcu_qsbr.h | 11 +++++++++++
> > > lib/rcu/version.map | 1 +
> > > 6 files changed, 43 insertions(+)
> > >
> > > diff --git a/lib/hash/rte_cuckoo_hash.c b/lib/hash/rte_cuckoo_hash.c
> > > index 70456754c4..3553f3efc7 100644
> > > --- a/lib/hash/rte_cuckoo_hash.c
> > > +++ b/lib/hash/rte_cuckoo_hash.c
> > > @@ -555,6 +555,15 @@ rte_hash_max_key_id(const struct rte_hash *h)
> > > return h->entries;
> > > }
> > >
> > > +int32_t
> > > +rte_hash_dq_count(const struct rte_hash *h)
> > > +{
> > > + if (h->dq =3D=3D NULL)
> > input arguments must be checked since this is a public API, the same is
> > true for rte_rcu_qsbr_dq_count()
> > > + return -EINVAL;
> > why not just return 0?
> > > +
> > > + return rte_rcu_qsbr_dq_count(h->dq);
> > > +}
> > > +
> > > int32_t
> > > rte_hash_count(const struct rte_hash *h)
> > > {
> > > diff --git a/lib/hash/rte_hash.h b/lib/hash/rte_hash.h
> > > index 7ecc021111..8ea97e297d 100644
> > > --- a/lib/hash/rte_hash.h
> > > +++ b/lib/hash/rte_hash.h
> > > @@ -193,6 +193,19 @@ rte_hash_free(struct rte_hash *h);
> > > void
> > > rte_hash_reset(struct rte_hash *h);
> > >
> > > +
> > > +/**
> > > + * Return the number of records in the defer queue of the hash table
> > > + * if RCU is enabled.
> > > + * @param h
> > > + * Hash table to query from
> > > + * @return
> > > + * - -EINVAL if parameters are invalid
> > > + * - A value indicating how many records were inserted in the tabl=
e.
> > did you mean how many records are kept in defer queue?
> > > + */
> > > +int32_t
> > > +rte_hash_dq_count(const struct rte_hash *h);
> > > +
> > > /**
> > > * Return the number of keys in the hash table
> > > * @param h
> > > diff --git a/lib/hash/version.map b/lib/hash/version.map
> > > index 6b2afebf6b..7f7b158cf1 100644
> > > --- a/lib/hash/version.map
> > > +++ b/lib/hash/version.map
> > > @@ -9,6 +9,7 @@ DPDK_24 {
> > > rte_hash_add_key_with_hash;
> > > rte_hash_add_key_with_hash_data;
> > > rte_hash_count;
> > > + rte_hash_dq_count;
> > new API must introduced as an experimental API. The same is true for
> > rte_rcu_qsbr_dq_count()
> > > rte_hash_crc32_alg;
> > > rte_hash_crc_set_alg;
> > > rte_hash_create;
> > > diff --git a/lib/rcu/rte_rcu_qsbr.c b/lib/rcu/rte_rcu_qsbr.c
> > > index bd0b83be0c..89f8da4c4c 100644
> > > --- a/lib/rcu/rte_rcu_qsbr.c
> > > +++ b/lib/rcu/rte_rcu_qsbr.c
> > > @@ -450,6 +450,14 @@ rte_rcu_qsbr_dq_reclaim(struct rte_rcu_qsbr_dq
> *dq, unsigned int n,
> > > return 0;
> > > }
> > >
> > > +/**
> > > + * Return the number of entries in a defer queue.
> > > + */
> > > +unsigned int rte_rcu_qsbr_dq_count(struct rte_rcu_qsbr_dq *dq)
> > > +{
> Please validate dq here.
>
> > > + return rte_ring_count(dq->r);
> > > +}
> > > +
> > > /* Delete a defer queue. */
> > > int
> > > rte_rcu_qsbr_dq_delete(struct rte_rcu_qsbr_dq *dq)
> > > diff --git a/lib/rcu/rte_rcu_qsbr.h b/lib/rcu/rte_rcu_qsbr.h
> > > index 23c9f89805..ed5a590edd 100644
> > > --- a/lib/rcu/rte_rcu_qsbr.h
> > > +++ b/lib/rcu/rte_rcu_qsbr.h
> > > @@ -794,6 +794,17 @@ int
> > > rte_rcu_qsbr_dq_reclaim(struct rte_rcu_qsbr_dq *dq, unsigned int n,
> > > unsigned int *freed, unsigned int *pending, unsigned int
> *available);
> > >
> > > +/**
> > > + * Return the number of entries in a defer queue.
> > > + *
> > > + * @param dq
> > > + * Defer queue.
> > > + * @return
> > > + * The number of entries in the defer queue.
> > > + */
> > > +unsigned int
> > > +rte_rcu_qsbr_dq_count(struct rte_rcu_qsbr_dq *dq);
> Agree on the need for this API in RCU
>
> > > +
> > > /**
> > > * Delete a defer queue.
> > > *
> > > diff --git a/lib/rcu/version.map b/lib/rcu/version.map
> > > index 982ffd59d9..f410ab41e7 100644
> > > --- a/lib/rcu/version.map
> > > +++ b/lib/rcu/version.map
> > > @@ -5,6 +5,7 @@ DPDK_24 {
> > > rte_rcu_qsbr_dq_create;
> > > rte_rcu_qsbr_dq_delete;
> > > rte_rcu_qsbr_dq_enqueue;
> > > + rte_rcu_qsbr_dq_count;
> > > rte_rcu_qsbr_dq_reclaim;
> > > rte_rcu_qsbr_dump;
> > > rte_rcu_qsbr_get_memsize;
> >
> > --
> > Regards,
> > Vladimir
> >
>
>
--0000000000000a8c1a0611d4ce10
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
<div dir=3D"ltr"><div>I appreciate=C2=A0that you gave me suggestions and co=
mments. I will make changes according to all your recommendations, but befo=
re that, I want to make everyone's minds clear. Then, I will apply modi=
fications.=C2=A0</div><br><div class=3D"gmail_quote"><div dir=3D"ltr" class=
=3D"gmail_attr">On Tue, Feb 20, 2024 at 2:35=E2=80=AFAM Honnappa Nagarahall=
i <<a href=3D"mailto:Honnappa.Nagarahalli@arm.com">Honnappa.Nagarahalli@=
arm.com</a>> wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"=
margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-lef=
t:1ex"><br>
<br>
> On Feb 19, 2024, at 3:28=E2=80=AFPM, Abdullah =C3=96mer Yama=C3=A7 <=
;<a href=3D"mailto:aomeryamac@gmail.com" target=3D"_blank">aomeryamac@gmail=
.com</a>> wrote:<br>
> <br>
> Hello,<br>
> <br>
> Let me explain a use case;<br>
> <br>
> I have a hash table whose key value is IP addresses, and data (let'=
;s say the username of the IP) is related to the IP address. The key point =
is matching these data with flows. Flows are dynamic, and this hash table i=
s dynamic, as well; both can change anytime. For example, when a flow start=
s, we look up the hash table with the corresponding IP and retrieve the use=
rname. We need to hold this username until the flow terminates, although we=
removed this IP key from the hash table (multithread). That's why we h=
ave RCU and defer queue is necessary for high performance. In my applicatio=
n, I need to know the number of IP-username entries. These numbers can be c=
alculated by rte_hash_count - defer queue size.<br>
The entries in the defer queue are not reclaimed (there is a probability th=
at all of them can be reclaimed) and hence they are not available for alloc=
ation. So, rte_hash_count - defer queue size might not give you the correct=
number you are expecting.<br>
<br>
Currently, there is no API in hash library that forces a reclaim. Does it m=
akes sense to have an API that just does the reclaim (and returns the numbe=
r of entries pending in the defer queue)? A call to rte_hash_count should p=
rovide the exact count you are looking for.</blockquote><div>You are right;=
no API in the hash library forces a reclaim. In my application, I periodic=
ally call rte_count to retrieve hash size, and this data is shown in my GUI=
. So that means I need to call regularly reclaim. I am trying to figure out=
which is better, calling reclaim or retrieving the defer queue=C2=A0size. =
Any comment about this?<br></div><blockquote class=3D"gmail_quote" style=3D=
"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-le=
ft:1ex">
> <br>
> I think if you need a non-blocking and multithreaded hash table, an RC=
U-enabled hash table is necessary. Also, this API is necessary if you need =
to get the actual matchable size.<br>
> <br>
> <br>
> <br>
> <br>
> <br>
> On Mon, Feb 19, 2024 at 8:36=E2=80=AFPM Medvedkin, Vladimir <<a hre=
f=3D"mailto:vladimir.medvedkin@intel.com" target=3D"_blank">vladimir.medved=
kin@intel.com</a>> wrote:<br>
> Hi Abdullah,<br>
> <br>
> Could you please tell more about use cases where this API may be usefu=
l?<br>
> <br>
> >a new API to get the hidden key count in the hash table if the rcu=
qsbr is enabled<br>
> <br>
> Here in commit message and down below in doxygen comments, I think thi=
s <br>
> statement should be more specific because rcu can be created with <br>
> RTE_HASH_QSBR_MODE_SYNC mode i.e. without defer queue.<br>
> <br>
> Also, new API must be reflected in release notes<br>
> <br>
> On 07/02/2024 15:33, Abdullah =C3=96mer Yama=C3=A7 wrote:<br>
> > This patch introduce a new API to get the hidden key count in the=
hash<br>
> > table if the rcu qsbr is enabled. When using rte_hash_count with =
rcu<br>
> > qsbr enabled, it will return the number of elements that are not =
in the<br>
> > free queue. Unless rte_rcu_qsbr_dq_reclaim is called, the number =
of<br>
> > elements in the defer queue will not be counted and freed. Theref=
ore I<br>
> > added a new API to get the number of hidden (defer queue) element=
s<br>
> > in the hash table. Then the user can calculate the total number o=
f<br>
> > elements that are available in the hash table.<br>
> ><br>
> > Signed-off-by: Abdullah =C3=96mer Yama=C3=A7 <<a href=3D"mailt=
o:aomeryamac@gmail.com" target=3D"_blank">aomeryamac@gmail.com</a>><br>
> ><br>
> > ---<br>
> > Cc: Honnappa Nagarahalli <<a href=3D"mailto:honnappa.nagarahal=
li@arm.com" target=3D"_blank">honnappa.nagarahalli@arm.com</a>><br>
> > Cc: Yipeng Wang <<a href=3D"mailto:yipeng1.wang@intel.com" tar=
get=3D"_blank">yipeng1.wang@intel.com</a>><br>
> > Cc: Sameh Gobriel <<a href=3D"mailto:sameh.gobriel@intel.com" =
target=3D"_blank">sameh.gobriel@intel.com</a>><br>
> > Cc: Bruce Richardson <<a href=3D"mailto:bruce.richardson@intel=
.com" target=3D"_blank">bruce.richardson@intel.com</a>><br>
> > Cc: Vladimir Medvedkin <<a href=3D"mailto:vladimir.medvedkin@i=
ntel.com" target=3D"_blank">vladimir.medvedkin@intel.com</a>><br>
> > ---<br>
> >=C2=A0 =C2=A0lib/hash/rte_cuckoo_hash.c |=C2=A0 9 +++++++++<br>
> >=C2=A0 =C2=A0lib/hash/rte_hash.h=C2=A0 =C2=A0 =C2=A0 =C2=A0 | 13 +=
++++++++++++<br>
> >=C2=A0 =C2=A0lib/hash/version.map=C2=A0 =C2=A0 =C2=A0 =C2=A0|=C2=
=A0 1 +<br>
> >=C2=A0 =C2=A0lib/rcu/rte_rcu_qsbr.c=C2=A0 =C2=A0 =C2=A0|=C2=A0 8 +=
+++++++<br>
> >=C2=A0 =C2=A0lib/rcu/rte_rcu_qsbr.h=C2=A0 =C2=A0 =C2=A0| 11 ++++++=
+++++<br>
> >=C2=A0 =C2=A0lib/rcu/version.map=C2=A0 =C2=A0 =C2=A0 =C2=A0 |=C2=
=A0 1 +<br>
> >=C2=A0 =C2=A06 files changed, 43 insertions(+)<br>
> ><br>
> > diff --git a/lib/hash/rte_cuckoo_hash.c b/lib/hash/rte_cuckoo_has=
h.c<br>
> > index 70456754c4..3553f3efc7 100644<br>
> > --- a/lib/hash/rte_cuckoo_hash.c<br>
> > +++ b/lib/hash/rte_cuckoo_hash.c<br>
> > @@ -555,6 +555,15 @@ rte_hash_max_key_id(const struct rte_hash *h=
)<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0return h-&g=
t;entries;<br>
> >=C2=A0 =C2=A0}<br>
> >=C2=A0 =C2=A0<br>
> > +int32_t<br>
> > +rte_hash_dq_count(const struct rte_hash *h)<br>
> > +{<br>
> > +=C2=A0 =C2=A0 =C2=A0if (h->dq =3D=3D NULL)<br>
> input arguments must be checked since this is a public API, the same i=
s <br>
> true for rte_rcu_qsbr_dq_count()<br>
> > +=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0return -EINVAL;<=
br>
> why not just return 0?<br>
> > +<br>
> > +=C2=A0 =C2=A0 =C2=A0return rte_rcu_qsbr_dq_count(h->dq);<br>
> > +}<br>
> > +<br>
> >=C2=A0 =C2=A0int32_t<br>
> >=C2=A0 =C2=A0rte_hash_count(const struct rte_hash *h)<br>
> >=C2=A0 =C2=A0{<br>
> > diff --git a/lib/hash/rte_hash.h b/lib/hash/rte_hash.h<br>
> > index 7ecc021111..8ea97e297d 100644<br>
> > --- a/lib/hash/rte_hash.h<br>
> > +++ b/lib/hash/rte_hash.h<br>
> > @@ -193,6 +193,19 @@ rte_hash_free(struct rte_hash *h);<br>
> >=C2=A0 =C2=A0void<br>
> >=C2=A0 =C2=A0rte_hash_reset(struct rte_hash *h);<br>
> >=C2=A0 =C2=A0<br>
> > +<br>
> > +/**<br>
> > + * Return the number of records in the defer queue of the hash t=
able<br>
> > + * if RCU is enabled.<br>
> > + * @param h<br>
> > + *=C2=A0 Hash table to query from<br>
> > + * @return<br>
> > + *=C2=A0 =C2=A0- -EINVAL if parameters are invalid<br>
> > + *=C2=A0 =C2=A0- A value indicating how many records were insert=
ed in the table.<br>
> did you mean how many records are kept in defer queue?<br>
> > + */<br>
> > +int32_t<br>
> > +rte_hash_dq_count(const struct rte_hash *h);<br>
> > +<br>
> >=C2=A0 =C2=A0/**<br>
> >=C2=A0 =C2=A0 * Return the number of keys in the hash table<br>
> >=C2=A0 =C2=A0 * @param h<br>
> > diff --git a/lib/hash/version.map b/lib/hash/version.map<br>
> > index 6b2afebf6b..7f7b158cf1 100644<br>
> > --- a/lib/hash/version.map<br>
> > +++ b/lib/hash/version.map<br>
> > @@ -9,6 +9,7 @@ DPDK_24 {<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_hash_add_key_with_hash;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_hash_add_key_with_hash_data;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_hash_count;<br>
> > +=C2=A0 =C2=A0 =C2=A0rte_hash_dq_count;<br>
> new API must introduced as an experimental API. The same is true for <=
br>
> rte_rcu_qsbr_dq_count()<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_hash_crc32_alg;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_hash_crc_set_alg;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_hash_create;<br>
> > diff --git a/lib/rcu/rte_rcu_qsbr.c b/lib/rcu/rte_rcu_qsbr.c<br>
> > index bd0b83be0c..89f8da4c4c 100644<br>
> > --- a/lib/rcu/rte_rcu_qsbr.c<br>
> > +++ b/lib/rcu/rte_rcu_qsbr.c<br>
> > @@ -450,6 +450,14 @@ rte_rcu_qsbr_dq_reclaim(struct rte_rcu_qsbr_=
dq *dq, unsigned int n,<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0return 0;<br>
> >=C2=A0 =C2=A0}<br>
> >=C2=A0 =C2=A0<br>
> > +/**<br>
> > + * Return the number of entries in a defer queue.<br>
> > + */<br>
> > +unsigned int rte_rcu_qsbr_dq_count(struct rte_rcu_qsbr_dq *dq)<b=
r>
> > +{<br>
Please validate dq here.<br>
<br>
> > +=C2=A0 =C2=A0 =C2=A0return rte_ring_count(dq->r);<br>
> > +}<br>
> > +<br>
> >=C2=A0 =C2=A0/* Delete a defer queue. */<br>
> >=C2=A0 =C2=A0int<br>
> >=C2=A0 =C2=A0rte_rcu_qsbr_dq_delete(struct rte_rcu_qsbr_dq *dq)<br=
>
> > diff --git a/lib/rcu/rte_rcu_qsbr.h b/lib/rcu/rte_rcu_qsbr.h<br>
> > index 23c9f89805..ed5a590edd 100644<br>
> > --- a/lib/rcu/rte_rcu_qsbr.h<br>
> > +++ b/lib/rcu/rte_rcu_qsbr.h<br>
> > @@ -794,6 +794,17 @@ int<br>
> >=C2=A0 =C2=A0rte_rcu_qsbr_dq_reclaim(struct rte_rcu_qsbr_dq *dq, u=
nsigned int n,<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0unsigned int *freed, unsigned int *pend=
ing, unsigned int *available);<br>
> >=C2=A0 =C2=A0<br>
> > +/**<br>
> > + * Return the number of entries in a defer queue.<br>
> > + *<br>
> > + * @param dq<br>
> > + *=C2=A0 =C2=A0Defer queue.<br>
> > + * @return<br>
> > + *=C2=A0 =C2=A0The number of entries in the defer queue.<br>
> > + */<br>
> > +unsigned int<br>
> > +rte_rcu_qsbr_dq_count(struct rte_rcu_qsbr_dq *dq);<br>
Agree on the need for this API in RCU<br>
<br>
> > +<br>
> >=C2=A0 =C2=A0/**<br>
> >=C2=A0 =C2=A0 * Delete a defer queue.<br>
> >=C2=A0 =C2=A0 *<br>
> > diff --git a/lib/rcu/version.map b/lib/rcu/version.map<br>
> > index 982ffd59d9..f410ab41e7 100644<br>
> > --- a/lib/rcu/version.map<br>
> > +++ b/lib/rcu/version.map<br>
> > @@ -5,6 +5,7 @@ DPDK_24 {<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_rcu_qsbr_dq_create;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_rcu_qsbr_dq_delete;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_rcu_qsbr_dq_enqueue;<br>
> > +=C2=A0 =C2=A0 =C2=A0rte_rcu_qsbr_dq_count;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_rcu_qsbr_dq_reclaim;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_rcu_qsbr_dump;<br>
> >=C2=A0 =C2=A0 =C2=A0 =C2=A0rte_rcu_qsbr_get_memsize;<br>
> <br>
> -- <br>
> Regards,<br>
> Vladimir<br>
> <br>
<br>
</blockquote></div></div>
--0000000000000a8c1a0611d4ce10--