[dpdk-dev] [PATCH v9 1/2] mem: balanced allocation of hugepages

[Ilya Maximets <i.maximets@samsung.com>]

Currently EAL allocates hugepages one by one not paying attention
from which NUMA node allocation was done.

Such behaviour leads to allocation failure if number of available
hugepages for application limited by cgroups or hugetlbfs and
memory requested not only from the first socket.

Example:
	# 90 x 1GB hugepages availavle in a system

	cgcreate -g hugetlb:/test
	# Limit to 32GB of hugepages
	cgset -r hugetlb.1GB.limit_in_bytes=34359738368 test
	# Request 4GB from each of 2 sockets
	cgexec -g hugetlb:test testpmd --socket-mem=4096,4096 ...

	EAL: SIGBUS: Cannot mmap more hugepages of size 1024 MB
	EAL: 32 not 90 hugepages of size 1024 MB allocated
	EAL: Not enough memory available on socket 1!
	     Requested: 4096MB, available: 0MB
	PANIC in rte_eal_init():
	Cannot init memory

	This happens beacause all allocated pages are
	on socket 0.

Fix this issue by setting mempolicy MPOL_PREFERRED for each hugepage
to one of requested nodes using following schema:

	1) Allocate essential hugepages:
		1.1) Allocate as many hugepages from numa N to
		     only fit requested memory for this numa.
		1.2) repeat 1.1 for all numa nodes.
	2) Try to map all remaining free hugepages in a round-robin
	   fashion.
	3) Sort pages and choose the most suitable.

In this case all essential memory will be allocated and all remaining
pages will be fairly distributed between all requested nodes.

New config option RTE_EAL_NUMA_AWARE_HUGEPAGES introduced and
enabled by default for linuxapp except armv7 and dpaa2.
Enabling of this option adds libnuma as a dependency for EAL.

Fixes: 77988fc08dc5 ("mem: fix allocating all free hugepages")

Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
---
 config/common_base                        |   1 +
 config/common_linuxapp                    |   1 +
 config/defconfig_arm-armv7a-linuxapp-gcc  |   3 +
 config/defconfig_arm64-dpaa2-linuxapp-gcc |   3 +
 lib/librte_eal/linuxapp/eal/Makefile      |   3 +
 lib/librte_eal/linuxapp/eal/eal_memory.c  | 120 ++++++++++++++++++++++++++++--
 mk/rte.app.mk                             |   3 +
 7 files changed, 126 insertions(+), 8 deletions(-)

diff --git a/config/common_base b/config/common_base
index f6aafd1..660588a 100644
--- a/config/common_base
+++ b/config/common_base
@@ -103,6 +103,7 @@ CONFIG_RTE_EAL_ALWAYS_PANIC_ON_ERROR=n
 CONFIG_RTE_EAL_IGB_UIO=n
 CONFIG_RTE_EAL_VFIO=n
 CONFIG_RTE_MALLOC_DEBUG=n
+CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES=n
 
 #
 # Recognize/ignore the AVX/AVX512 CPU flags for performance/power testing.
diff --git a/config/common_linuxapp b/config/common_linuxapp
index b3cf41b..64bef87 100644
--- a/config/common_linuxapp
+++ b/config/common_linuxapp
@@ -35,6 +35,7 @@
 CONFIG_RTE_EXEC_ENV="linuxapp"
 CONFIG_RTE_EXEC_ENV_LINUXAPP=y
 
+CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES=y
 CONFIG_RTE_EAL_IGB_UIO=y
 CONFIG_RTE_EAL_VFIO=y
 CONFIG_RTE_KNI_KMOD=y
diff --git a/config/defconfig_arm-armv7a-linuxapp-gcc b/config/defconfig_arm-armv7a-linuxapp-gcc
index 19607eb..e06b1d4 100644
--- a/config/defconfig_arm-armv7a-linuxapp-gcc
+++ b/config/defconfig_arm-armv7a-linuxapp-gcc
@@ -47,6 +47,9 @@ CONFIG_RTE_ARCH_STRICT_ALIGN=y
 CONFIG_RTE_TOOLCHAIN="gcc"
 CONFIG_RTE_TOOLCHAIN_GCC=y
 
+# NUMA is not supported on ARM
+CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES=n
+
 # ARM doesn't have support for vmware TSC map
 CONFIG_RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORT=n
 
diff --git a/config/defconfig_arm64-dpaa2-linuxapp-gcc b/config/defconfig_arm64-dpaa2-linuxapp-gcc
index 2304ab6..f78449d 100644
--- a/config/defconfig_arm64-dpaa2-linuxapp-gcc
+++ b/config/defconfig_arm64-dpaa2-linuxapp-gcc
@@ -45,6 +45,9 @@ CONFIG_RTE_CACHE_LINE_SIZE=64
 
 CONFIG_RTE_PKTMBUF_HEADROOM=256
 
+# Doesn't support NUMA
+CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES=y
+
 #
 # Compile Support Libraries for DPAA2
 #
diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index 640afd0..8651e27 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -50,6 +50,9 @@ LDLIBS += -ldl
 LDLIBS += -lpthread
 LDLIBS += -lgcc_s
 LDLIBS += -lrt
+ifeq ($(CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES),y)
+LDLIBS += -lnuma
+endif
 
 # specific to linuxapp exec-env
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) := eal.c
diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c b/lib/librte_eal/linuxapp/eal/eal_memory.c
index e17c9cb..647d89c 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memory.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
@@ -54,6 +54,10 @@
 #include <sys/time.h>
 #include <signal.h>
 #include <setjmp.h>
+#ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
+#include <numa.h>
+#include <numaif.h>
+#endif
 
 #include <rte_log.h>
 #include <rte_memory.h>
@@ -348,6 +352,14 @@ static int huge_wrap_sigsetjmp(void)
 	return sigsetjmp(huge_jmpenv, 1);
 }
 
+#ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
+/* Callback for numa library. */
+void numa_error(char *where)
+{
+	RTE_LOG(ERR, EAL, "%s failed: %s\n", where, strerror(errno));
+}
+#endif
+
 /*
  * Mmap all hugepages of hugepage table: it first open a file in
  * hugetlbfs, then mmap() hugepage_sz data in it. If orig is set, the
@@ -356,18 +368,78 @@ static int huge_wrap_sigsetjmp(void)
  * map continguous physical blocks in contiguous virtual blocks.
  */
 static unsigned
-map_all_hugepages(struct hugepage_file *hugepg_tbl,
-		struct hugepage_info *hpi, int orig)
+map_all_hugepages(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi,
+		  uint64_t *essential_memory __rte_unused, int orig)
 {
 	int fd;
 	unsigned i;
 	void *virtaddr;
 	void *vma_addr = NULL;
 	size_t vma_len = 0;
+#ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
+	int node_id = -1;
+	int essential_prev = 0;
+	int oldpolicy;
+	struct bitmask *oldmask = numa_allocate_nodemask();
+	bool have_numa = true;
+	unsigned long maxnode = 0;
+
+	/* Check if kernel supports NUMA. */
+	if (numa_available() != 0) {
+		RTE_LOG(DEBUG, EAL, "NUMA is not supported.\n");
+		have_numa = false;
+	}
+
+	if (orig && have_numa) {
+		RTE_LOG(DEBUG, EAL, "Trying to obtain current memory policy.\n");
+		if (get_mempolicy(&oldpolicy, oldmask->maskp,
+				  oldmask->size + 1, 0, 0) < 0) {
+			RTE_LOG(ERR, EAL,
+				"Failed to get current mempolicy: %s. "
+				"Assuming MPOL_DEFAULT.\n", strerror(errno));
+			oldpolicy = MPOL_DEFAULT;
+		}
+		for (i = 0; i < RTE_MAX_NUMA_NODES; i++)
+			if (internal_config.socket_mem[i])
+				maxnode = i + 1;
+	}
+#endif
 
 	for (i = 0; i < hpi->num_pages[0]; i++) {
 		uint64_t hugepage_sz = hpi->hugepage_sz;
 
+#ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
+		if (maxnode) {
+			unsigned int j;
+
+			for (j = 0; j < maxnode; j++)
+				if (essential_memory[j])
+					break;
+
+			if (j == maxnode) {
+				node_id = (node_id + 1) % maxnode;
+				while (!internal_config.socket_mem[node_id]) {
+					node_id++;
+					node_id %= maxnode;
+				}
+				essential_prev = 0;
+			} else {
+				node_id = j;
+				essential_prev = essential_memory[j];
+
+				if (essential_memory[j] < hugepage_sz)
+					essential_memory[j] = 0;
+				else
+					essential_memory[j] -= hugepage_sz;
+			}
+
+			RTE_LOG(DEBUG, EAL,
+				"Setting policy MPOL_PREFERRED for socket %d\n",
+				node_id);
+			numa_set_preferred(node_id);
+		}
+#endif
+
 		if (orig) {
 			hugepg_tbl[i].file_id = i;
 			hugepg_tbl[i].size = hugepage_sz;
@@ -422,7 +494,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl,
 		if (fd < 0) {
 			RTE_LOG(DEBUG, EAL, "%s(): open failed: %s\n", __func__,
 					strerror(errno));
-			return i;
+			goto out;
 		}
 
 		/* map the segment, and populate page tables,
@@ -433,7 +505,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl,
 			RTE_LOG(DEBUG, EAL, "%s(): mmap failed: %s\n", __func__,
 					strerror(errno));
 			close(fd);
-			return i;
+			goto out;
 		}
 
 		if (orig) {
@@ -458,7 +530,12 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl,
 				munmap(virtaddr, hugepage_sz);
 				close(fd);
 				unlink(hugepg_tbl[i].filepath);
-				return i;
+#ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
+				if (maxnode)
+					essential_memory[node_id] =
+						essential_prev;
+#endif
+				goto out;
 			}
 			*(int *)virtaddr = 0;
 		}
@@ -469,7 +546,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl,
 			RTE_LOG(DEBUG, EAL, "%s(): Locking file failed:%s \n",
 				__func__, strerror(errno));
 			close(fd);
-			return i;
+			goto out;
 		}
 
 		close(fd);
@@ -478,6 +555,22 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl,
 		vma_len -= hugepage_sz;
 	}
 
+out:
+#ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
+	if (maxnode) {
+		RTE_LOG(DEBUG, EAL,
+			"Restoring previous memory policy: %d\n", oldpolicy);
+		if (oldpolicy == MPOL_DEFAULT) {
+			numa_set_localalloc();
+		} else if (set_mempolicy(oldpolicy, oldmask->maskp,
+					 oldmask->size + 1) < 0) {
+			RTE_LOG(ERR, EAL, "Failed to restore mempolicy: %s\n",
+				strerror(errno));
+			numa_set_localalloc();
+		}
+	}
+	numa_free_cpumask(oldmask);
+#endif
 	return i;
 }
 
@@ -562,6 +655,11 @@ find_numasocket(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi)
 			if (hugepg_tbl[i].orig_va == va) {
 				hugepg_tbl[i].socket_id = socket_id;
 				hp_count++;
+#ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
+				RTE_LOG(DEBUG, EAL,
+					"Hugepage %s is on socket %d\n",
+					hugepg_tbl[i].filepath, socket_id);
+#endif
 			}
 		}
 	}
@@ -1000,6 +1098,11 @@ rte_eal_hugepage_init(void)
 
 	huge_register_sigbus();
 
+	/* make a copy of socket_mem, needed for balanced allocation. */
+	for (i = 0; i < RTE_MAX_NUMA_NODES; i++)
+		memory[i] = internal_config.socket_mem[i];
+
+
 	/* map all hugepages and sort them */
 	for (i = 0; i < (int)internal_config.num_hugepage_sizes; i ++){
 		unsigned pages_old, pages_new;
@@ -1017,7 +1120,8 @@ rte_eal_hugepage_init(void)
 
 		/* map all hugepages available */
 		pages_old = hpi->num_pages[0];
-		pages_new = map_all_hugepages(&tmp_hp[hp_offset], hpi, 1);
+		pages_new = map_all_hugepages(&tmp_hp[hp_offset], hpi,
+					      memory, 1);
 		if (pages_new < pages_old) {
 			RTE_LOG(DEBUG, EAL,
 				"%d not %d hugepages of size %u MB allocated\n",
@@ -1060,7 +1164,7 @@ rte_eal_hugepage_init(void)
 		      sizeof(struct hugepage_file), cmp_physaddr);
 
 		/* remap all hugepages */
-		if (map_all_hugepages(&tmp_hp[hp_offset], hpi, 0) !=
+		if (map_all_hugepages(&tmp_hp[hp_offset], hpi, NULL, 0) !=
 		    hpi->num_pages[0]) {
 			RTE_LOG(ERR, EAL, "Failed to remap %u MB pages\n",
 					(unsigned)(hpi->hugepage_sz / 0x100000));
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index bcaf1b3..4fe22d1 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -186,6 +186,9 @@ ifeq ($(CONFIG_RTE_BUILD_SHARED_LIB),n)
 # The static libraries do not know their dependencies.
 # So linking with static library requires explicit dependencies.
 _LDLIBS-$(CONFIG_RTE_LIBRTE_EAL)            += -lrt
+ifeq ($(CONFIG_RTE_EXEC_ENV_LINUXAPP)$(CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES),yy)
+_LDLIBS-$(CONFIG_RTE_LIBRTE_EAL)            += -lnuma
+endif
 _LDLIBS-$(CONFIG_RTE_LIBRTE_SCHED)          += -lm
 _LDLIBS-$(CONFIG_RTE_LIBRTE_SCHED)          += -lrt
 _LDLIBS-$(CONFIG_RTE_LIBRTE_METER)          += -lm
-- 
2.7.4