X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libringbuffer%2Fshm.c;h=909991ed27c6f1ada4a04426e396d232d126df8e;hb=4d4838bad480d48424bddc686f5ad0089e28ac94;hp=0153578c93a2cfddf3bdd69ae57324b516086651;hpb=bfcda6cea270952898ea122c375f2ed19105adef;p=lttng-ust.git

diff --git a/libringbuffer/shm.c b/libringbuffer/shm.c
index 0153578c..909991ed 100644
--- a/libringbuffer/shm.c
+++ b/libringbuffer/shm.c
@@ -33,11 +33,14 @@
 #include <dirent.h>
 #include <lttng/align.h>
 #include <limits.h>
+#include <stdbool.h>
 #ifdef HAVE_LIBNUMA
 #include <numa.h>
+#include <numaif.h>
 #endif
 #include <helper.h>
 #include <ust-fd.h>
+#include "mmap.h"
 
 /*
  * Ensure we have the required amount of space available by writing 0
@@ -152,7 +155,7 @@ struct shm_object *_shm_object_table_alloc_shm(struct shm_object_table *table,
 
 	/* memory_map: mmap */
 	memory_map = mmap(NULL, memory_map_size, PROT_READ | PROT_WRITE,
-			  MAP_SHARED, shmfd, 0);
+			  MAP_SHARED | LTTNG_MAP_POPULATE, shmfd, 0);
 	if (memory_map == MAP_FAILED) {
 		PERROR("mmap");
 		goto error_mmap;
@@ -244,6 +247,24 @@ alloc_error:
 	return NULL;
 }
 
+/*
+ * libnuma prints errors on the console even for numa_available().
+ * Work-around this limitation by using get_mempolicy() directly to
+ * check whether the kernel supports mempolicy.
+ */
+#ifdef HAVE_LIBNUMA
+static bool lttng_is_numa_available(void)
+{
+	int ret;
+
+	ret = get_mempolicy(NULL, NULL, 0, NULL, 0);
+	if (ret && errno == ENOSYS) {
+		return false;
+	}
+	return numa_available() > 0;
+}
+#endif
+
 struct shm_object *shm_object_table_alloc(struct shm_object_table *table,
 			size_t memory_map_size,
 			enum shm_object_type type,
@@ -252,16 +273,20 @@ struct shm_object *shm_object_table_alloc(struct shm_object_table *table,
 {
 	struct shm_object *shm_object;
 #ifdef HAVE_LIBNUMA
-	int oldnode, node;
-
-	oldnode = numa_preferred();
-	if (cpu >= 0) {
-		node = numa_node_of_cpu(cpu);
-		if (node >= 0)
-			numa_set_preferred(node);
+	int oldnode = 0, node;
+	bool numa_avail;
+
+	numa_avail = lttng_is_numa_available();
+	if (numa_avail) {
+		oldnode = numa_preferred();
+		if (cpu >= 0) {
+			node = numa_node_of_cpu(cpu);
+			if (node >= 0)
+				numa_set_preferred(node);
+		}
+		if (cpu < 0 || node < 0)
+			numa_set_localalloc();
 	}
-	if (cpu < 0 || node < 0)
-		numa_set_localalloc();
 #endif /* HAVE_LIBNUMA */
 	switch (type) {
 	case SHM_OBJECT_SHM:
@@ -275,7 +300,8 @@ struct shm_object *shm_object_table_alloc(struct shm_object_table *table,
 		assert(0);
 	}
 #ifdef HAVE_LIBNUMA
-	numa_set_preferred(oldnode);
+	if (numa_avail)
+		numa_set_preferred(oldnode);
 #endif /* HAVE_LIBNUMA */
 	return shm_object;
 }
@@ -316,7 +342,7 @@ struct shm_object *shm_object_table_append_shm(struct shm_object_table *table,
 
 	/* memory_map: mmap */
 	memory_map = mmap(NULL, memory_map_size, PROT_READ | PROT_WRITE,
-			  MAP_SHARED, shm_fd, 0);
+			  MAP_SHARED | LTTNG_MAP_POPULATE, shm_fd, 0);
 	if (memory_map == MAP_FAILED) {
 		PERROR("mmap");
 		goto error_mmap;