[dpdk-dev] [RFC 19/23] eal/memzone: add support for reserving physically contiguous memzones

[Anatoly Burakov <anatoly.burakov@intel.com>]

This adds a new set of _contig API's to rte_memzone.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 lib/librte_eal/common/eal_common_memzone.c  |  44 ++++++++
 lib/librte_eal/common/include/rte_memzone.h | 158 ++++++++++++++++++++++++++++
 2 files changed, 202 insertions(+)

diff --git a/lib/librte_eal/common/eal_common_memzone.c b/lib/librte_eal/common/eal_common_memzone.c
index 542ae90..a9a4bef 100644
--- a/lib/librte_eal/common/eal_common_memzone.c
+++ b/lib/librte_eal/common/eal_common_memzone.c
@@ -200,6 +200,12 @@ memzone_reserve_aligned_thread_unsafe(const char *name, size_t len,
 		socket_id = SOCKET_ID_ANY;
 
 	if (len == 0) {
+		/* len == 0 is only allowed for non-contiguous zones */
+		// TODO: technically, we can make it work, is it worth it?
+		if (contig) {
+			rte_errno = EINVAL;
+			return NULL;
+		}
 		if (bound != 0)
 			requested_len = bound;
 		else {
@@ -285,6 +291,19 @@ rte_memzone_reserve_bounded(const char *name, size_t len, int socket_id,
 
 /*
  * Return a pointer to a correctly filled memzone descriptor (with a
+ * specified alignment and boundary). If the allocation cannot be done,
+ * return NULL.
+ */
+const struct rte_memzone *
+rte_memzone_reserve_bounded_contig(const char *name, size_t len, int socket_id,
+			    unsigned flags, unsigned align, unsigned bound)
+{
+	return rte_memzone_reserve_thread_safe(name, len, socket_id, flags,
+					       align, bound, true);
+}
+
+/*
+ * Return a pointer to a correctly filled memzone descriptor (with a
  * specified alignment). If the allocation cannot be done, return NULL.
  */
 const struct rte_memzone *
@@ -296,6 +315,18 @@ rte_memzone_reserve_aligned(const char *name, size_t len, int socket_id,
 }
 
 /*
+ * Return a pointer to a correctly filled memzone descriptor (with a
+ * specified alignment). If the allocation cannot be done, return NULL.
+ */
+const struct rte_memzone *
+rte_memzone_reserve_aligned_contig(const char *name, size_t len, int socket_id,
+			    unsigned flags, unsigned align)
+{
+	return rte_memzone_reserve_thread_safe(name, len, socket_id, flags,
+					       align, 0, true);
+}
+
+/*
  * Return a pointer to a correctly filled memzone descriptor. If the
  * allocation cannot be done, return NULL.
  */
@@ -308,6 +339,19 @@ rte_memzone_reserve(const char *name, size_t len, int socket_id,
 					       false);
 }
 
+/*
+ * Return a pointer to a correctly filled memzone descriptor. If the
+ * allocation cannot be done, return NULL.
+ */
+const struct rte_memzone *
+rte_memzone_reserve_contig(const char *name, size_t len, int socket_id,
+		    unsigned flags)
+{
+	return rte_memzone_reserve_thread_safe(name, len, socket_id,
+					       flags, RTE_CACHE_LINE_SIZE, 0,
+					       true);
+}
+
 int
 rte_memzone_free(const struct rte_memzone *mz)
 {
diff --git a/lib/librte_eal/common/include/rte_memzone.h b/lib/librte_eal/common/include/rte_memzone.h
index 6f0ba18..237fd31 100644
--- a/lib/librte_eal/common/include/rte_memzone.h
+++ b/lib/librte_eal/common/include/rte_memzone.h
@@ -257,6 +257,164 @@ const struct rte_memzone *rte_memzone_reserve_bounded(const char *name,
 			unsigned flags, unsigned align, unsigned bound);
 
 /**
+ * Reserve a portion of physical memory.
+ *
+ * This function reserves some memory and returns a pointer to a
+ * correctly filled memzone descriptor. If the allocation cannot be
+ * done, return NULL.
+ *
+ * @param name
+ *   The name of the memzone. If it already exists, the function will
+ *   fail and return NULL.
+ * @param len
+ *   The size of the memory to be reserved. If it
+ *   is 0, the biggest contiguous zone will be reserved.
+ * @param socket_id
+ *   The socket identifier in the case of
+ *   NUMA. The value can be SOCKET_ID_ANY if there is no NUMA
+ *   constraint for the reserved zone.
+ * @param flags
+ *   The flags parameter is used to request memzones to be
+ *   taken from specifically sized hugepages.
+ *   - RTE_MEMZONE_2MB - Reserved from 2MB pages
+ *   - RTE_MEMZONE_1GB - Reserved from 1GB pages
+ *   - RTE_MEMZONE_16MB - Reserved from 16MB pages
+ *   - RTE_MEMZONE_16GB - Reserved from 16GB pages
+ *   - RTE_MEMZONE_256KB - Reserved from 256KB pages
+ *   - RTE_MEMZONE_256MB - Reserved from 256MB pages
+ *   - RTE_MEMZONE_512MB - Reserved from 512MB pages
+ *   - RTE_MEMZONE_4GB - Reserved from 4GB pages
+ *   - RTE_MEMZONE_SIZE_HINT_ONLY - Allow alternative page size to be used if
+ *                                  the requested page size is unavailable.
+ *                                  If this flag is not set, the function
+ *                                  will return error on an unavailable size
+ *                                  request.
+ * @return
+ *   A pointer to a correctly-filled read-only memzone descriptor, or NULL
+ *   on error.
+ *   On error case, rte_errno will be set appropriately:
+ *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
+ *    - E_RTE_SECONDARY - function was called from a secondary process instance
+ *    - ENOSPC - the maximum number of memzones has already been allocated
+ *    - EEXIST - a memzone with the same name already exists
+ *    - ENOMEM - no appropriate memory area found in which to create memzone
+ *    - EINVAL - invalid parameters
+ */
+const struct rte_memzone *rte_memzone_reserve_contig(const char *name,
+					      size_t len, int socket_id,
+					      unsigned flags);
+
+/**
+ * Reserve a portion of physical memory with alignment on a specified
+ * boundary.
+ *
+ * This function reserves some memory with alignment on a specified
+ * boundary, and returns a pointer to a correctly filled memzone
+ * descriptor. If the allocation cannot be done or if the alignment
+ * is not a power of 2, returns NULL.
+ *
+ * @param name
+ *   The name of the memzone. If it already exists, the function will
+ *   fail and return NULL.
+ * @param len
+ *   The size of the memory to be reserved. If it
+ *   is 0, the biggest contiguous zone will be reserved.
+ * @param socket_id
+ *   The socket identifier in the case of
+ *   NUMA. The value can be SOCKET_ID_ANY if there is no NUMA
+ *   constraint for the reserved zone.
+ * @param flags
+ *   The flags parameter is used to request memzones to be
+ *   taken from specifically sized hugepages.
+ *   - RTE_MEMZONE_2MB - Reserved from 2MB pages
+ *   - RTE_MEMZONE_1GB - Reserved from 1GB pages
+ *   - RTE_MEMZONE_16MB - Reserved from 16MB pages
+ *   - RTE_MEMZONE_16GB - Reserved from 16GB pages
+ *   - RTE_MEMZONE_256KB - Reserved from 256KB pages
+ *   - RTE_MEMZONE_256MB - Reserved from 256MB pages
+ *   - RTE_MEMZONE_512MB - Reserved from 512MB pages
+ *   - RTE_MEMZONE_4GB - Reserved from 4GB pages
+ *   - RTE_MEMZONE_SIZE_HINT_ONLY - Allow alternative page size to be used if
+ *                                  the requested page size is unavailable.
+ *                                  If this flag is not set, the function
+ *                                  will return error on an unavailable size
+ *                                  request.
+ * @param align
+ *   Alignment for resulting memzone. Must be a power of 2.
+ * @return
+ *   A pointer to a correctly-filled read-only memzone descriptor, or NULL
+ *   on error.
+ *   On error case, rte_errno will be set appropriately:
+ *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
+ *    - E_RTE_SECONDARY - function was called from a secondary process instance
+ *    - ENOSPC - the maximum number of memzones has already been allocated
+ *    - EEXIST - a memzone with the same name already exists
+ *    - ENOMEM - no appropriate memory area found in which to create memzone
+ *    - EINVAL - invalid parameters
+ */
+const struct rte_memzone *rte_memzone_reserve_aligned_contig(const char *name,
+			size_t len, int socket_id,
+			unsigned flags, unsigned align);
+
+/**
+ * Reserve a portion of physical memory with specified alignment and
+ * boundary.
+ *
+ * This function reserves some memory with specified alignment and
+ * boundary, and returns a pointer to a correctly filled memzone
+ * descriptor. If the allocation cannot be done or if the alignment
+ * or boundary are not a power of 2, returns NULL.
+ * Memory buffer is reserved in a way, that it wouldn't cross specified
+ * boundary. That implies that requested length should be less or equal
+ * then boundary.
+ *
+ * @param name
+ *   The name of the memzone. If it already exists, the function will
+ *   fail and return NULL.
+ * @param len
+ *   The size of the memory to be reserved. If it
+ *   is 0, the biggest contiguous zone will be reserved.
+ * @param socket_id
+ *   The socket identifier in the case of
+ *   NUMA. The value can be SOCKET_ID_ANY if there is no NUMA
+ *   constraint for the reserved zone.
+ * @param flags
+ *   The flags parameter is used to request memzones to be
+ *   taken from specifically sized hugepages.
+ *   - RTE_MEMZONE_2MB - Reserved from 2MB pages
+ *   - RTE_MEMZONE_1GB - Reserved from 1GB pages
+ *   - RTE_MEMZONE_16MB - Reserved from 16MB pages
+ *   - RTE_MEMZONE_16GB - Reserved from 16GB pages
+ *   - RTE_MEMZONE_256KB - Reserved from 256KB pages
+ *   - RTE_MEMZONE_256MB - Reserved from 256MB pages
+ *   - RTE_MEMZONE_512MB - Reserved from 512MB pages
+ *   - RTE_MEMZONE_4GB - Reserved from 4GB pages
+ *   - RTE_MEMZONE_SIZE_HINT_ONLY - Allow alternative page size to be used if
+ *                                  the requested page size is unavailable.
+ *                                  If this flag is not set, the function
+ *                                  will return error on an unavailable size
+ *                                  request.
+ * @param align
+ *   Alignment for resulting memzone. Must be a power of 2.
+ * @param bound
+ *   Boundary for resulting memzone. Must be a power of 2 or zero.
+ *   Zero value implies no boundary condition.
+ * @return
+ *   A pointer to a correctly-filled read-only memzone descriptor, or NULL
+ *   on error.
+ *   On error case, rte_errno will be set appropriately:
+ *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
+ *    - E_RTE_SECONDARY - function was called from a secondary process instance
+ *    - ENOSPC - the maximum number of memzones has already been allocated
+ *    - EEXIST - a memzone with the same name already exists
+ *    - ENOMEM - no appropriate memory area found in which to create memzone
+ *    - EINVAL - invalid parameters
+ */
+const struct rte_memzone *rte_memzone_reserve_bounded_contig(const char *name,
+			size_t len, int socket_id,
+			unsigned flags, unsigned align, unsigned bound);
+
+/**
  * Free a memzone.
  *
  * @param mz
-- 
2.7.4