DPDK patches and discussions
 help / color / mirror / Atom feed
* [PATCH] eal: allow swapping of malloc heaps
@ 2023-09-15 12:27 Bruce Richardson
  2023-09-15 13:10 ` [PATCH v2] " Bruce Richardson
                   ` (2 more replies)
  0 siblings, 3 replies; 7+ messages in thread
From: Bruce Richardson @ 2023-09-15 12:27 UTC (permalink / raw)
  To: dev; +Cc: Bruce Richardson, Anatoly Burakov

The external memory functions in DPDK allow the addition of externally
access memory to malloc heaps, but with one major restriction - the
memory must be allocated to an application-created heap, not one of the
standard DPDK heaps for a NUMA node.

This restriction makes it difficult - if not impossible - to use
externally allocated memory for DPDK by default. However, even if the
restriction is relaxed, so we can add external memory to e.g. the socket
0 heap, there would be no way to guarantee that the external memory
would be used in preference to the standard DPDK hugepage memory for a
given allocation.

To give appropriately defined behaviour, a better solution is to allow
the application to explicitly swap a pair of heaps. With this one new
API in place, it allows the user to configure a new malloc heap, add
external memory to it, and then replace a standard socket heap with the
newly created one - thereby guaranteeing future allocations from the
external memory.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/eal/common/malloc_heap.c | 18 ++++++++++++++++++
 lib/eal/include/rte_malloc.h | 25 +++++++++++++++++++++++++
 lib/eal/version.map          |  2 ++
 3 files changed, 45 insertions(+)

diff --git a/lib/eal/common/malloc_heap.c b/lib/eal/common/malloc_heap.c
index 6b6cf9174c..e5d0ad6b52 100644
--- a/lib/eal/common/malloc_heap.c
+++ b/lib/eal/common/malloc_heap.c
@@ -1320,6 +1320,24 @@ malloc_heap_add_external_memory(struct malloc_heap *heap,
 	return 0;
 }
 
+int
+rte_malloc_heap_swap_socket(int socket1, int socket2)
+{
+	const int h1 = malloc_socket_to_heap_id(socket1);
+	if (h1 < 0 || h1 > RTE_MAX_HEAPS)
+		return -1;
+
+	const int h2 = malloc_socket_to_heap_id(socket2);
+	if (h2 < 0 || h2 > RTE_MAX_HEAPS)
+		return -1;
+
+	struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
+	int tmp = mcfg->malloc_heaps[h1].socket_id;
+	mcfg->malloc_heaps[h1].socket_id = mcfg->malloc_heaps[h2].socket_id;
+	mcfg->malloc_heaps[h2].socket_id = tmp;
+	return 0;
+}
+
 int
 malloc_heap_remove_external_memory(struct malloc_heap *heap, void *va_addr,
 		size_t len)
diff --git a/lib/eal/include/rte_malloc.h b/lib/eal/include/rte_malloc.h
index 54a8ac211e..fa70ca7430 100644
--- a/lib/eal/include/rte_malloc.h
+++ b/lib/eal/include/rte_malloc.h
@@ -490,6 +490,31 @@ rte_malloc_heap_get_socket(const char *name);
 int
 rte_malloc_heap_socket_is_external(int socket_id);
 
+/**
+ * Swap the heaps for the given socket ids
+ *
+ * This causes the heaps for the given socket ids to be swapped, allowing
+ * external memory registered as a malloc heap to become the new default memory
+ * for a standard numa node. For example, to have allocations on socket 0 come
+ * from external memory, the following sequence of API calls can be used:
+ *   - rte_malloc_heap_create(<name>)
+ *   - rte_malloc_heap_memory_add(<name>,....)
+ *   - id = rte_malloc_heap_get_socket(<name>)
+ *   - rte_malloc_heap_swap_sockets(0, id)
+ * Following these calls, allocations for the old memory allocated on socket 0,
+ * can be made by passing "id" as the socket_id parameter
+ *
+ * @param socket1
+ *   The socket id of the first heap to swap
+ * @param socket2
+ *   The socket id of the second heap to swap
+ * @return
+ *   0 on success, -1 on error
+ */
+__rte_experimental
+int
+rte_malloc_heap_swap_socket(int socket1, int socket2);
+
 /**
  * Dump statistics.
  *
diff --git a/lib/eal/version.map b/lib/eal/version.map
index 7940431e5a..b06ee7219e 100644
--- a/lib/eal/version.map
+++ b/lib/eal/version.map
@@ -417,6 +417,8 @@ EXPERIMENTAL {
 	# added in 23.07
 	rte_memzone_max_get;
 	rte_memzone_max_set;
+
+	rte_malloc_heap_swap_socket;
 };
 
 INTERNAL {
-- 
2.39.2


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v2] eal: allow swapping of malloc heaps
  2023-09-15 12:27 [PATCH] eal: allow swapping of malloc heaps Bruce Richardson
@ 2023-09-15 13:10 ` Bruce Richardson
  2023-09-15 15:43 ` [PATCH] " Stephen Hemminger
  2023-09-18 16:32 ` [PATCH v3 0/2] Enable apps to use external memory as native Bruce Richardson
  2 siblings, 0 replies; 7+ messages in thread
From: Bruce Richardson @ 2023-09-15 13:10 UTC (permalink / raw)
  To: dev; +Cc: Anatoly Burakov, Bruce Richardson

The external memory functions in DPDK allow the addition of externally
access memory to malloc heaps, but with one major restriction - the
memory must be allocated to an application-created heap, not one of the
standard DPDK heaps for a NUMA node.

This restriction makes it difficult - if not impossible - to use
externally allocated memory for DPDK by default. However, even if the
restriction is relaxed, so we can add external memory to e.g. the socket
0 heap, there would be no way to guarantee that the external memory
would be used in preference to the standard DPDK hugepage memory for a
given allocation.

To give appropriately defined behaviour, a better solution is to allow
the application to explicitly swap a pair of heaps. With this one new
API in place, it allows the user to configure a new malloc heap, add
external memory to it, and then replace a standard socket heap with the
newly created one - thereby guaranteeing future allocations from the
external memory.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
V2: Fix doxygen comment issue on doc builds. Mark code snippet using
    @code...@endcode to avoid issues with "<" symbols
---
 lib/eal/common/malloc_heap.c | 18 ++++++++++++++++++
 lib/eal/include/rte_malloc.h | 28 ++++++++++++++++++++++++++++
 lib/eal/version.map          |  2 ++
 3 files changed, 48 insertions(+)

diff --git a/lib/eal/common/malloc_heap.c b/lib/eal/common/malloc_heap.c
index 6b6cf9174c..e5d0ad6b52 100644
--- a/lib/eal/common/malloc_heap.c
+++ b/lib/eal/common/malloc_heap.c
@@ -1320,6 +1320,24 @@ malloc_heap_add_external_memory(struct malloc_heap *heap,
 	return 0;
 }
 
+int
+rte_malloc_heap_swap_socket(int socket1, int socket2)
+{
+	const int h1 = malloc_socket_to_heap_id(socket1);
+	if (h1 < 0 || h1 > RTE_MAX_HEAPS)
+		return -1;
+
+	const int h2 = malloc_socket_to_heap_id(socket2);
+	if (h2 < 0 || h2 > RTE_MAX_HEAPS)
+		return -1;
+
+	struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
+	int tmp = mcfg->malloc_heaps[h1].socket_id;
+	mcfg->malloc_heaps[h1].socket_id = mcfg->malloc_heaps[h2].socket_id;
+	mcfg->malloc_heaps[h2].socket_id = tmp;
+	return 0;
+}
+
 int
 malloc_heap_remove_external_memory(struct malloc_heap *heap, void *va_addr,
 		size_t len)
diff --git a/lib/eal/include/rte_malloc.h b/lib/eal/include/rte_malloc.h
index 54a8ac211e..410211aa44 100644
--- a/lib/eal/include/rte_malloc.h
+++ b/lib/eal/include/rte_malloc.h
@@ -490,6 +490,34 @@ rte_malloc_heap_get_socket(const char *name);
 int
 rte_malloc_heap_socket_is_external(int socket_id);
 
+/**
+ * Swap the heaps for the given socket ids
+ *
+ * This causes the heaps for the given socket ids to be swapped, allowing
+ * external memory registered as a malloc heap to become the new default memory
+ * for a standard numa node. For example, to have allocations on socket 0 come
+ * from external memory, the following sequence of API calls can be used:
+ * @code
+ *   rte_malloc_heap_create(<name>)
+ *   rte_malloc_heap_memory_add(<name>,....)
+ *   id = rte_malloc_heap_get_socket(<name>)
+ *   rte_malloc_heap_swap_socket(0, id)
+ * @endcode
+ *
+ * Following these calls, allocations for the old memory allocated on socket 0,
+ * can be made by passing "id" as the socket_id parameter
+ *
+ * @param socket1
+ *   The socket id of the first heap to swap
+ * @param socket2
+ *   The socket id of the second heap to swap
+ * @return
+ *   0 on success, -1 on error
+ */
+__rte_experimental
+int
+rte_malloc_heap_swap_socket(int socket1, int socket2);
+
 /**
  * Dump statistics.
  *
diff --git a/lib/eal/version.map b/lib/eal/version.map
index 7940431e5a..b06ee7219e 100644
--- a/lib/eal/version.map
+++ b/lib/eal/version.map
@@ -417,6 +417,8 @@ EXPERIMENTAL {
 	# added in 23.07
 	rte_memzone_max_get;
 	rte_memzone_max_set;
+
+	rte_malloc_heap_swap_socket;
 };
 
 INTERNAL {
-- 
2.39.2


^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] eal: allow swapping of malloc heaps
  2023-09-15 12:27 [PATCH] eal: allow swapping of malloc heaps Bruce Richardson
  2023-09-15 13:10 ` [PATCH v2] " Bruce Richardson
@ 2023-09-15 15:43 ` Stephen Hemminger
  2023-09-18 16:32 ` [PATCH v3 0/2] Enable apps to use external memory as native Bruce Richardson
  2 siblings, 0 replies; 7+ messages in thread
From: Stephen Hemminger @ 2023-09-15 15:43 UTC (permalink / raw)
  To: Bruce Richardson; +Cc: dev, Anatoly Burakov

On Fri, 15 Sep 2023 13:27:03 +0100
Bruce Richardson <bruce.richardson@intel.com> wrote:

> The external memory functions in DPDK allow the addition of externally
> access memory to malloc heaps, but with one major restriction - the
> memory must be allocated to an application-created heap, not one of the
> standard DPDK heaps for a NUMA node.
> 
> This restriction makes it difficult - if not impossible - to use
> externally allocated memory for DPDK by default. However, even if the
> restriction is relaxed, so we can add external memory to e.g. the socket
> 0 heap, there would be no way to guarantee that the external memory
> would be used in preference to the standard DPDK hugepage memory for a
> given allocation.
> 
> To give appropriately defined behaviour, a better solution is to allow
> the application to explicitly swap a pair of heaps. With this one new
> API in place, it allows the user to configure a new malloc heap, add
> external memory to it, and then replace a standard socket heap with the
> newly created one - thereby guaranteeing future allocations from the
> external memory.
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> ---

Should document any restrictions about when this can be done.
Doesn't look thread safe. Would expect that application would do this
just after EAL init before doing any work.

What happens to memory allocated from old heap.

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v3 0/2] Enable apps to use external memory as native
  2023-09-15 12:27 [PATCH] eal: allow swapping of malloc heaps Bruce Richardson
  2023-09-15 13:10 ` [PATCH v2] " Bruce Richardson
  2023-09-15 15:43 ` [PATCH] " Stephen Hemminger
@ 2023-09-18 16:32 ` Bruce Richardson
  2023-09-18 16:32   ` [PATCH v3 1/2] eal: add flag to indicate non-EAL malloc heaps Bruce Richardson
                     ` (2 more replies)
  2 siblings, 3 replies; 7+ messages in thread
From: Bruce Richardson @ 2023-09-18 16:32 UTC (permalink / raw)
  To: dev; +Cc: Bruce Richardson

Sometimes apps (or perhaps DPDK driver components) may want to allow
use of "external" i.e. non EAL allocated, memory as though it were
standard DPDK memory. This patchset provides the ability to do this,
by: firstly, adding an explicit flag to indicate non-EAL memory,
rather than relying on the socket_id implicitly, and then secondly,
allowing heaps to be swapped, so an external heap can be used as the
default heap for socket 0 or 1, etc.

V3:
* Expand to 2 patch set, adding patch to tag external memory
  explicitly, before adding the swap function
* Add locks to improve thread safety of the swap opperation.
* Add additional notes to function to clarify usage.

V2:
* Fix doxygen comment issue on doc builds

Bruce Richardson (2):
  eal: add flag to indicate non-EAL malloc heaps
  eal: allow swapping of malloc heaps

 lib/eal/common/malloc_heap.c | 46 ++++++++++++++++++++++++++++--------
 lib/eal/common/malloc_heap.h |  1 +
 lib/eal/common/malloc_mp.c   |  5 ++--
 lib/eal/common/rte_malloc.c  | 14 ++++++-----
 lib/eal/include/rte_malloc.h | 34 ++++++++++++++++++++++++++
 lib/eal/version.map          |  2 ++
 6 files changed, 83 insertions(+), 19 deletions(-)

--
2.39.2


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v3 1/2] eal: add flag to indicate non-EAL malloc heaps
  2023-09-18 16:32 ` [PATCH v3 0/2] Enable apps to use external memory as native Bruce Richardson
@ 2023-09-18 16:32   ` Bruce Richardson
  2023-09-18 16:32   ` [PATCH v3 2/2] eal: allow swapping of " Bruce Richardson
  2023-09-18 16:44   ` [PATCH v3 0/2] Enable apps to use external memory as native Stephen Hemminger
  2 siblings, 0 replies; 7+ messages in thread
From: Bruce Richardson @ 2023-09-18 16:32 UTC (permalink / raw)
  To: dev; +Cc: Bruce Richardson, Anatoly Burakov

Rather than relying implicitly on the socket_id value to identify
external heaps vs internal ones that can be expanded on demand by adding
more hugepages, we add an "is_external" flag to the heap structure. As
we do so, we change the heap initialization to use designated
initializers to guarantee as we add new fields that they are properly
zeroed on init. As it stands, many fields are not explicitly set on
first init of the internal malloc heaps.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/eal/common/malloc_heap.c | 22 ++++++++++++----------
 lib/eal/common/malloc_heap.h |  1 +
 lib/eal/common/malloc_mp.c   |  5 ++---
 lib/eal/common/rte_malloc.c  | 14 ++++++++------
 4 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/lib/eal/common/malloc_heap.c b/lib/eal/common/malloc_heap.c
index 6b6cf9174c..4fa38fcd44 100644
--- a/lib/eal/common/malloc_heap.c
+++ b/lib/eal/common/malloc_heap.c
@@ -668,7 +668,7 @@ malloc_heap_alloc_on_heap_id(const char *type, size_t size,
 	 * we just need to request more memory first.
 	 */
 
-	socket_id = rte_socket_id_by_idx(heap_id);
+	socket_id = heap->is_external ? -1 : rte_socket_id_by_idx(heap_id);
 	/*
 	 * if socket ID is negative, we cannot find a socket ID for this heap -
 	 * which means it's an external heap. those can have unexpected page
@@ -1362,19 +1362,17 @@ malloc_heap_create(struct malloc_heap *heap, const char *heap_name)
 	}
 
 	/* initialize empty heap */
-	heap->alloc_count = 0;
-	heap->first = NULL;
-	heap->last = NULL;
+	*heap = (struct malloc_heap) {
+		.is_external = 1,
+		.socket_id = next_socket_id,
+		.lock = RTE_SPINLOCK_INITIALIZER,
+	};
 	LIST_INIT(heap->free_head);
-	rte_spinlock_init(&heap->lock);
-	heap->total_size = 0;
-	heap->socket_id = next_socket_id;
+	strlcpy(heap->name, heap_name, RTE_HEAP_NAME_MAX_LEN);
 
 	/* we hold a global mem hotplug writelock, so it's safe to increment */
 	mcfg->next_socket_id++;
 
-	/* set up name */
-	strlcpy(heap->name, heap_name, RTE_HEAP_NAME_MAX_LEN);
 	return 0;
 }
 
@@ -1425,8 +1423,12 @@ rte_eal_malloc_heap_init(void)
 
 			snprintf(heap_name, sizeof(heap_name),
 					"socket_%i", socket_id);
+
+			*heap = (struct malloc_heap){
+				.lock = RTE_SPINLOCK_INITIALIZER,
+				.socket_id = socket_id,
+			};
 			strlcpy(heap->name, heap_name, RTE_HEAP_NAME_MAX_LEN);
-			heap->socket_id = socket_id;
 		}
 	}
 
diff --git a/lib/eal/common/malloc_heap.h b/lib/eal/common/malloc_heap.h
index 8f3ab57154..e23cc01fb3 100644
--- a/lib/eal/common/malloc_heap.h
+++ b/lib/eal/common/malloc_heap.h
@@ -23,6 +23,7 @@ struct malloc_elem;
  */
 struct malloc_heap {
 	rte_spinlock_t lock;
+	uint32_t is_external:1;
 	LIST_HEAD(, malloc_elem) free_head[RTE_HEAP_NUM_FREELISTS];
 	struct malloc_elem *volatile first;
 	struct malloc_elem *volatile last;
diff --git a/lib/eal/common/malloc_mp.c b/lib/eal/common/malloc_mp.c
index 7270c2ec90..d5ab6d8351 100644
--- a/lib/eal/common/malloc_mp.c
+++ b/lib/eal/common/malloc_mp.c
@@ -242,10 +242,9 @@ handle_alloc_request(const struct malloc_mp_req *m,
 	/*
 	 * for allocations, we must only use internal heaps, but since the
 	 * rte_malloc_heap_socket_is_external() is thread-safe and we're already
-	 * read-locked, we'll have to take advantage of the fact that internal
-	 * socket ID's are always lower than RTE_MAX_NUMA_NODES.
+	 * read-locked, we'll check directly here.
 	 */
-	if (heap->socket_id >= RTE_MAX_NUMA_NODES) {
+	if (heap->is_external == 1) {
 		RTE_LOG(ERR, EAL, "Attempting to allocate from external heap\n");
 		return -1;
 	}
diff --git a/lib/eal/common/rte_malloc.c b/lib/eal/common/rte_malloc.c
index ebafef3f6c..5f40acabee 100644
--- a/lib/eal/common/rte_malloc.c
+++ b/lib/eal/common/rte_malloc.c
@@ -314,7 +314,7 @@ rte_malloc_heap_socket_is_external(int socket_id)
 
 		if ((int)tmp->socket_id == socket_id) {
 			/* external memory always has large socket ID's */
-			ret = tmp->socket_id >= RTE_MAX_NUMA_NODES;
+			ret = tmp->is_external;
 			break;
 		}
 	}
@@ -421,7 +421,7 @@ rte_malloc_heap_memory_add(const char *heap_name, void *va_addr, size_t len,
 		ret = -1;
 		goto unlock;
 	}
-	if (heap->socket_id < RTE_MAX_NUMA_NODES) {
+	if (heap->is_external == 0) {
 		/* cannot add memory to internal heaps */
 		rte_errno = EPERM;
 		ret = -1;
@@ -469,7 +469,7 @@ rte_malloc_heap_memory_remove(const char *heap_name, void *va_addr, size_t len)
 		ret = -1;
 		goto unlock;
 	}
-	if (heap->socket_id < RTE_MAX_NUMA_NODES) {
+	if (heap->is_external == 0) {
 		/* cannot remove memory from internal heaps */
 		rte_errno = EPERM;
 		ret = -1;
@@ -520,7 +520,7 @@ sync_memory(const char *heap_name, void *va_addr, size_t len, bool attach)
 		goto unlock;
 	}
 	/* we shouldn't be able to sync to internal heaps */
-	if (heap->socket_id < RTE_MAX_NUMA_NODES) {
+	if (heap->is_external == 0) {
 		rte_errno = EPERM;
 		ret = -1;
 		goto unlock;
@@ -648,8 +648,10 @@ rte_malloc_heap_destroy(const char *heap_name)
 		ret = -1;
 		goto unlock;
 	}
-	/* we shouldn't be able to destroy internal heaps */
-	if (heap->socket_id < RTE_MAX_NUMA_NODES) {
+	/* we shouldn't be able to destroy internal heaps, or external heaps
+	 * configured to have an internal numa socket id
+	 */
+	if (heap->socket_id < RTE_MAX_NUMA_NODES || heap->is_external == 0) {
 		rte_errno = EPERM;
 		ret = -1;
 		goto unlock;
-- 
2.39.2


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v3 2/2] eal: allow swapping of malloc heaps
  2023-09-18 16:32 ` [PATCH v3 0/2] Enable apps to use external memory as native Bruce Richardson
  2023-09-18 16:32   ` [PATCH v3 1/2] eal: add flag to indicate non-EAL malloc heaps Bruce Richardson
@ 2023-09-18 16:32   ` Bruce Richardson
  2023-09-18 16:44   ` [PATCH v3 0/2] Enable apps to use external memory as native Stephen Hemminger
  2 siblings, 0 replies; 7+ messages in thread
From: Bruce Richardson @ 2023-09-18 16:32 UTC (permalink / raw)
  To: dev; +Cc: Bruce Richardson, Anatoly Burakov

The external memory functions in DPDK allow the addition of externally
access memory to malloc heaps, but with one major restriction - the
memory must be allocated to an application-created heap, not one of the
standard DPDK heaps for a NUMA node.

This restriction makes it difficult - if not impossible - to use
externally allocated memory for DPDK by default. However, even if the
restriction is relaxed, so we can add external memory to e.g. the socket
0 heap, there would be no way to guarantee that the external memory
would be used in preference to the standard DPDK hugepage memory for a
given allocation.

To give appropriately defined behaviour, a better solution is to allow
the application to explicitly swap a pair of heaps. With this one new
API in place, it allows the user to configure a new malloc heap, add
external memory to it, and then replace a standard socket heap with the
newly created one - thereby guaranteeing future allocations from the
external memory.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/eal/common/malloc_heap.c | 24 ++++++++++++++++++++++++
 lib/eal/include/rte_malloc.h | 34 ++++++++++++++++++++++++++++++++++
 lib/eal/version.map          |  2 ++
 3 files changed, 60 insertions(+)

diff --git a/lib/eal/common/malloc_heap.c b/lib/eal/common/malloc_heap.c
index 4fa38fcd44..eba75111ca 100644
--- a/lib/eal/common/malloc_heap.c
+++ b/lib/eal/common/malloc_heap.c
@@ -1320,6 +1320,30 @@ malloc_heap_add_external_memory(struct malloc_heap *heap,
 	return 0;
 }
 
+int
+rte_malloc_heap_swap_socket(int socket1, int socket2)
+{
+	const int h1 = malloc_socket_to_heap_id(socket1);
+	if (h1 < 0 || h1 > RTE_MAX_HEAPS)
+		return -1;
+
+	const int h2 = malloc_socket_to_heap_id(socket2);
+	if (h2 < 0 || h2 > RTE_MAX_HEAPS)
+		return -1;
+
+
+	rte_mcfg_mem_write_lock();
+	do {
+		struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
+		int tmp = mcfg->malloc_heaps[h1].socket_id;
+		mcfg->malloc_heaps[h1].socket_id = mcfg->malloc_heaps[h2].socket_id;
+		mcfg->malloc_heaps[h2].socket_id = tmp;
+	} while (0);
+	rte_mcfg_mem_write_unlock();
+
+	return 0;
+}
+
 int
 malloc_heap_remove_external_memory(struct malloc_heap *heap, void *va_addr,
 		size_t len)
diff --git a/lib/eal/include/rte_malloc.h b/lib/eal/include/rte_malloc.h
index 54a8ac211e..df356a5efe 100644
--- a/lib/eal/include/rte_malloc.h
+++ b/lib/eal/include/rte_malloc.h
@@ -490,6 +490,40 @@ rte_malloc_heap_get_socket(const char *name);
 int
 rte_malloc_heap_socket_is_external(int socket_id);
 
+/**
+ * Swap the heaps for the given socket ids
+ *
+ * This causes the heaps for the given socket ids to be swapped, allowing
+ * external memory registered as a malloc heap to become the new default memory
+ * for a standard numa node. For example, to have allocations on socket 0 come
+ * from external memory, the following sequence of API calls can be used:
+ * @code
+ *   rte_malloc_heap_create(<name>)
+ *   rte_malloc_heap_memory_add(<name>,....)
+ *   id = rte_malloc_heap_get_socket(<name>)
+ *   rte_malloc_heap_swap_socket(0, id)
+ * @endcode
+ *
+ * Following these calls, allocations for the old memory allocated on socket 0,
+ * can be made by passing "id" as the socket_id parameter.
+ *
+ * @note: It is recommended that this function be used only after EAL initialization,
+ *   before any temporary objects are created from the DPDK heaps.
+ * @note: Since any objects allocated using rte_malloc and similar functions, track
+ *   the heaps via pointers, any already-allocated objects will be returned to their
+ *   original heaps, even after a call to this function.
+ *
+ * @param socket1
+ *   The socket id of the first heap to swap
+ * @param socket2
+ *   The socket id of the second heap to swap
+ * @return
+ *   0 on success, -1 on error
+ */
+__rte_experimental
+int
+rte_malloc_heap_swap_socket(int socket1, int socket2);
+
 /**
  * Dump statistics.
  *
diff --git a/lib/eal/version.map b/lib/eal/version.map
index 7940431e5a..b06ee7219e 100644
--- a/lib/eal/version.map
+++ b/lib/eal/version.map
@@ -417,6 +417,8 @@ EXPERIMENTAL {
 	# added in 23.07
 	rte_memzone_max_get;
 	rte_memzone_max_set;
+
+	rte_malloc_heap_swap_socket;
 };
 
 INTERNAL {
-- 
2.39.2


^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH v3 0/2] Enable apps to use external memory as native
  2023-09-18 16:32 ` [PATCH v3 0/2] Enable apps to use external memory as native Bruce Richardson
  2023-09-18 16:32   ` [PATCH v3 1/2] eal: add flag to indicate non-EAL malloc heaps Bruce Richardson
  2023-09-18 16:32   ` [PATCH v3 2/2] eal: allow swapping of " Bruce Richardson
@ 2023-09-18 16:44   ` Stephen Hemminger
  2 siblings, 0 replies; 7+ messages in thread
From: Stephen Hemminger @ 2023-09-18 16:44 UTC (permalink / raw)
  To: Bruce Richardson; +Cc: dev

On Mon, 18 Sep 2023 17:32:04 +0100
Bruce Richardson <bruce.richardson@intel.com> wrote:

> Sometimes apps (or perhaps DPDK driver components) may want to allow
> use of "external" i.e. non EAL allocated, memory as though it were
> standard DPDK memory. This patchset provides the ability to do this,
> by: firstly, adding an explicit flag to indicate non-EAL memory,
> rather than relying on the socket_id implicitly, and then secondly,
> allowing heaps to be swapped, so an external heap can be used as the
> default heap for socket 0 or 1, etc.
> 
> V3:
> * Expand to 2 patch set, adding patch to tag external memory
>   explicitly, before adding the swap function
> * Add locks to improve thread safety of the swap opperation.
> * Add additional notes to function to clarify usage.
> 
> V2:
> * Fix doxygen comment issue on doc builds
> 
> Bruce Richardson (2):
>   eal: add flag to indicate non-EAL malloc heaps
>   eal: allow swapping of malloc heaps
> 
>  lib/eal/common/malloc_heap.c | 46 ++++++++++++++++++++++++++++--------
>  lib/eal/common/malloc_heap.h |  1 +
>  lib/eal/common/malloc_mp.c   |  5 ++--
>  lib/eal/common/rte_malloc.c  | 14 ++++++-----
>  lib/eal/include/rte_malloc.h | 34 ++++++++++++++++++++++++++
>  lib/eal/version.map          |  2 ++
>  6 files changed, 83 insertions(+), 19 deletions(-)
> 
> --
> 2.39.2
> 

Series-Acked-by: Stephen Hemminger <stephen@networkplumber.org>

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2023-09-18 16:44 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-09-15 12:27 [PATCH] eal: allow swapping of malloc heaps Bruce Richardson
2023-09-15 13:10 ` [PATCH v2] " Bruce Richardson
2023-09-15 15:43 ` [PATCH] " Stephen Hemminger
2023-09-18 16:32 ` [PATCH v3 0/2] Enable apps to use external memory as native Bruce Richardson
2023-09-18 16:32   ` [PATCH v3 1/2] eal: add flag to indicate non-EAL malloc heaps Bruce Richardson
2023-09-18 16:32   ` [PATCH v3 2/2] eal: allow swapping of " Bruce Richardson
2023-09-18 16:44   ` [PATCH v3 0/2] Enable apps to use external memory as native Stephen Hemminger

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).