[PATCH] reorder: introduce API to obtain memory footprint

[PATCH] reorder: introduce API to obtain memory footprint

[Volodymyr Fialko]

At present, it is not easy to determine the memory requirement for the
reorder buffer without delving into its implementation details.
To facilitate the use of reorder buffer with user allocation, a new API
`rte_reorder_memory_footprint_get()` is introduced.
This API will provide the amount of required memory for reorder buffer.

Signed-off-by: Volodymyr Fialko <vfialko@marvell.com>
---
 app/test/test_reorder.c   |  8 ++++----
 lib/reorder/rte_reorder.c | 13 +++++++++----
 lib/reorder/rte_reorder.h | 16 ++++++++++++++++
 lib/reorder/version.map   |  2 ++
 4 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/app/test/test_reorder.c b/app/test/test_reorder.c
index f391597a78..6daa913ef9 100644
--- a/app/test/test_reorder.c
+++ b/app/test/test_reorder.c
@@ -68,12 +68,12 @@ test_reorder_init(void)
 	struct rte_reorder_buffer *b = NULL;
 	unsigned int size;
 	/*
-	 * The minimum memory area size that should be passed to library is,
-	 * sizeof(struct rte_reorder_buffer) + (2 * size * sizeof(struct rte_mbuf *));
+	 * The minimum memory area size that should be passed to library determined
+	 * by rte_reorder_memory_footprint_get().
 	 * Otherwise error will be thrown
 	 */
 
-	size = 100;
+	size = rte_reorder_memory_footprint_get(REORDER_BUFFER_SIZE) - 1;
 	b = rte_reorder_init(b, size, "PKT1", REORDER_BUFFER_SIZE);
 	TEST_ASSERT((b == NULL) && (rte_errno == EINVAL),
 			"No error on init with NULL buffer.");
@@ -84,7 +84,7 @@ test_reorder_init(void)
 			"No error on init with invalid mem zone size.");
 	rte_free(b);
 
-	size = 262336;
+	size = rte_reorder_memory_footprint_get(REORDER_BUFFER_SIZE);
 	b = rte_malloc(NULL, size, 0);
 	b = rte_reorder_init(b, size, "PKT1", REORDER_BUFFER_SIZE_INVALID);
 	TEST_ASSERT((b == NULL) && (rte_errno == EINVAL),
diff --git a/lib/reorder/rte_reorder.c b/lib/reorder/rte_reorder.c
index 66d2cc07b7..f55f383700 100644
--- a/lib/reorder/rte_reorder.c
+++ b/lib/reorder/rte_reorder.c
@@ -54,12 +54,17 @@ struct rte_reorder_buffer {
 static void
 rte_reorder_free_mbufs(struct rte_reorder_buffer *b);
 
+unsigned int
+rte_reorder_memory_footprint_get(unsigned int size)
+{
+	return sizeof(struct rte_reorder_buffer) + (2 * size * sizeof(struct rte_mbuf *));
+}
+
 struct rte_reorder_buffer *
 rte_reorder_init(struct rte_reorder_buffer *b, unsigned int bufsize,
 		const char *name, unsigned int size)
 {
-	const unsigned int min_bufsize = sizeof(*b) +
-					(2 * size * sizeof(struct rte_mbuf *));
+	const unsigned int min_bufsize = rte_reorder_memory_footprint_get(size);
 	static const struct rte_mbuf_dynfield reorder_seqn_dynfield_desc = {
 		.name = RTE_REORDER_SEQN_DYNFIELD_NAME,
 		.size = sizeof(rte_reorder_seqn_t),
@@ -148,8 +153,8 @@ rte_reorder_create(const char *name, unsigned socket_id, unsigned int size)
 {
 	struct rte_reorder_buffer *b = NULL;
 	struct rte_tailq_entry *te, *te_inserted;
-	const unsigned int bufsize = sizeof(struct rte_reorder_buffer) +
-					(2 * size * sizeof(struct rte_mbuf *));
+
+	const unsigned int bufsize = rte_reorder_memory_footprint_get(size);
 
 	/* Check user arguments. */
 	if (!rte_is_power_of_2(size)) {
diff --git a/lib/reorder/rte_reorder.h b/lib/reorder/rte_reorder.h
index 9a5998f2f6..16dc4ee400 100644
--- a/lib/reorder/rte_reorder.h
+++ b/lib/reorder/rte_reorder.h
@@ -212,6 +212,22 @@ __rte_experimental
 unsigned int
 rte_reorder_min_seqn_set(struct rte_reorder_buffer *b, rte_reorder_seqn_t min_seqn);
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Determine the amount of memory needed by the reorder buffer to accommodate a given number of
+ * elements. @see rte_reorder_init()
+ *
+ * @param size
+ *   Number of elements that can be stored in reorder buffer.
+ * @return
+ *   Reorder buffer footprint measured in bytes.
+ */
+__rte_experimental
+unsigned int
+rte_reorder_memory_footprint_get(unsigned int size);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/reorder/version.map b/lib/reorder/version.map
index e21b91f526..7ff6a622f4 100644
--- a/lib/reorder/version.map
+++ b/lib/reorder/version.map
@@ -19,4 +19,6 @@ EXPERIMENTAL {
 	# added in 23.03
 	rte_reorder_drain_up_to_seqn;
 	rte_reorder_min_seqn_set;
+	# added in 23.07
+	rte_reorder_memory_footprint_get;
 };
-- 
2.34.1

Re: [PATCH] reorder: introduce API to obtain memory footprint

[Thomas Monjalon]

Hello,

2 comments below

14/04/2023 10:52, Volodymyr Fialko:
> At present, it is not easy to determine the memory requirement for the
> reorder buffer without delving into its implementation details.
> To facilitate the use of reorder buffer with user allocation, a new API
> `rte_reorder_memory_footprint_get()` is introduced.
> This API will provide the amount of required memory for reorder buffer.
> 
> Signed-off-by: Volodymyr Fialko <vfialko@marvell.com>
[...]
> +__rte_experimental
> +unsigned int
> +rte_reorder_memory_footprint_get(unsigned int size);

It should be of type size_t.
But I see other functions in this lib use the wrong type (unsigned int).

Like previous patches for the reorder library from Volodymyr,
the official maintainer (Reshma) is not reviewing.
Does it mean Reshma is not interested anymore in this maintenance?

Applied, thanks.

RE: [PATCH] reorder: introduce API to obtain memory footprint

[Pattan, Reshma]

> -----Original Message-----
> From: Thomas Monjalon <thomas@monjalon.net>
> 
> Like previous patches for the reorder library from Volodymyr, the official
> maintainer (Reshma) is not reviewing.
> Does it mean Reshma is not interested anymore in this maintenance?

Hi Thomas,

I would like to drop from the maintainers responsibility for this library.
If any one is interested to be a Maintainer please do remove my name and add a new Maintainer name to the Maintainers list.


Thanks,
Reshma

RE: [PATCH] reorder: introduce API to obtain memory footprint

[Volodymyr Fialko]

Hi Thomas and Reshma,

I would be interested in taking on the role of maintaining the reorder library.

> -----Original Message-----
> From: Pattan, Reshma <reshma.pattan@intel.com>
> Sent: Friday, June 2, 2023 1:06 PM
> To: Thomas Monjalon <thomas@monjalon.net>; Volodymyr Fialko <vfialko@marvell.com>
> Cc: dev@dpdk.org; Jerin Jacob Kollanukkaran <jerinj@marvell.com>; Anoob Joseph
> <anoobj@marvell.com>
> Subject: [EXT] RE: [PATCH] reorder: introduce API to obtain memory footprint
> 
> External Email
> 
> ----------------------------------------------------------------------
> 
> 
> > -----Original Message-----
> > From: Thomas Monjalon <thomas@monjalon.net>
> >
> > Like previous patches for the reorder library from Volodymyr, the
> > official maintainer (Reshma) is not reviewing.
> > Does it mean Reshma is not interested anymore in this maintenance?
> 
> Hi Thomas,
> 
> I would like to drop from the maintainers responsibility for this library.
> If any one is interested to be a Maintainer please do remove my name and add a new Maintainer
> name to the Maintainers list.
> 
> 
> Thanks,
> Reshma
> 

Re: [PATCH] reorder: introduce API to obtain memory footprint

[Thomas Monjalon]

02/06/2023 13:30, Volodymyr Fialko:
> Hi Thomas and Reshma,
> 
> I would be interested in taking on the role of maintaining the reorder library.

If Reshma accepts, please send a patch to replace Reshma.
It will require an ack from Reshma.
Thank you both


> From: Pattan, Reshma <reshma.pattan@intel.com>
> > > From: Thomas Monjalon <thomas@monjalon.net>
> > >
> > > Like previous patches for the reorder library from Volodymyr, the
> > > official maintainer (Reshma) is not reviewing.
> > > Does it mean Reshma is not interested anymore in this maintenance?
> > 
> > Hi Thomas,
> > 
> > I would like to drop from the maintainers responsibility for this library.
> > If any one is interested to be a Maintainer please do remove my name and add a new Maintainer
> > name to the Maintainers list.
> > 
> > 
> > Thanks,
> > Reshma

RE: [PATCH] reorder: introduce API to obtain memory footprint

[Pattan, Reshma]

> -----Original Message-----
> From: Thomas Monjalon <thomas@monjalon.net>

<snip>

> Subject: Re: [PATCH] reorder: introduce API to obtain memory footprint
> 
> 02/06/2023 13:30, Volodymyr Fialko:
> > Hi Thomas and Reshma,
> >
> > I would be interested in taking on the role of maintaining the reorder library.
> 
> If Reshma accepts, please send a patch to replace Reshma.
> It will require an ack from Reshma.
> Thank you both
> 

I am fine with the idea, I will ack the patch.

Thanks,
Reshma

> 
<Snip>