diff options
Diffstat (limited to 'tools/libxl/libxl_numa.c')
| -rw-r--r-- | tools/libxl/libxl_numa.c | 88 |
1 files changed, 64 insertions, 24 deletions
diff --git a/tools/libxl/libxl_numa.c b/tools/libxl/libxl_numa.c index d95ed2af09..5301ec4f0c 100644 --- a/tools/libxl/libxl_numa.c +++ b/tools/libxl/libxl_numa.c @@ -105,30 +105,48 @@ static int comb_next(comb_iter_t it, int n, int k) /* NUMA automatic placement (see libxl_internal.h for details) */ /* - * This function turns a k-combination iterator into a node map. - * This means the bits in the node map corresponding to the indexes - * of the given combination are the ones that will be set. - * For example, if the iterator represents the combination { 0, 2, 4}, - * the node map will have bits #0, #2 and #4 set. + * This function turns a k-combination iterator into a node map, + * given another map, telling us which nodes should be considered. + * + * This means the bits that are set in suitable_nodemap and that + * corresponds to the indexes of the given combination are the ones + * that will be set in nodemap. + * + * For example, given a fully set suitable_nodemap, if the iterator + * represents the combination { 0, 2, 4}, nodmeap will have bits #0, + * #2 and #4 set. + * On the other hand, if, say, suitable_nodemap=01011011, the same + * iterator will cause bits #1, #4 and #7 of nodemap to be set. */ -static void comb_get_nodemap(comb_iter_t it, libxl_bitmap *nodemap, int k) +static void comb_get_nodemap(comb_iter_t it, libxl_bitmap *suitable_nodemap, + libxl_bitmap *nodemap, int k) { - int i; + int i, m = 0, n = 0; libxl_bitmap_set_none(nodemap); - for (i = 0; i < k; i++) - libxl_bitmap_set(nodemap, it[i]); + libxl_for_each_set_bit(i, *suitable_nodemap) { + /* Check wether the n-th set bit of suitable_nodemap + * matches with the m-th element of the iterator (and, + * only if it does, advance to the next one) */ + if (m < k && n == it[m]) { + libxl_bitmap_set(nodemap, i); + m++; + } + n++; + } } /* Retrieve the number of cpus that the nodes that are part of the nodemap - * span. */ + * span and are also set in suitable_cpumap. */ static int nodemap_to_nr_cpus(libxl_cputopology *tinfo, int nr_cpus, + const libxl_bitmap *suitable_cpumap, const libxl_bitmap *nodemap) { int i, nodes_cpus = 0; for (i = 0; i < nr_cpus; i++) { - if (libxl_bitmap_test(nodemap, tinfo[i].node)) + if (libxl_bitmap_test(suitable_cpumap, i) && + libxl_bitmap_test(nodemap, tinfo[i].node)) nodes_cpus++; } return nodes_cpus; @@ -242,6 +260,7 @@ static int count_cpus_per_node(libxl_cputopology *tinfo, int nr_cpus, int libxl__get_numa_candidate(libxl__gc *gc, uint32_t min_free_memkb, int min_cpus, int min_nodes, int max_nodes, + const libxl_bitmap *suitable_cpumap, libxl__numa_candidate_cmpf numa_cmpf, libxl__numa_candidate *cndt_out, int *cndt_found) @@ -249,11 +268,12 @@ int libxl__get_numa_candidate(libxl__gc *gc, libxl__numa_candidate new_cndt; libxl_cputopology *tinfo = NULL; libxl_numainfo *ninfo = NULL; - int nr_nodes = 0, nr_cpus = 0; - libxl_bitmap nodemap; + int nr_nodes = 0, nr_suit_nodes, nr_cpus = 0; + libxl_bitmap suitable_nodemap, nodemap; int rc = 0; libxl_bitmap_init(&nodemap); + libxl_bitmap_init(&suitable_nodemap); libxl__numa_candidate_init(&new_cndt); /* Get platform info and prepare the map for testing the combinations */ @@ -300,6 +320,15 @@ int libxl__get_numa_candidate(libxl__gc *gc, if (rc) goto out; + /* Allocate and prepare the map of the node that can be utilized for + * placement, basing on the map of suitable cpus. */ + rc = libxl_node_bitmap_alloc(CTX, &suitable_nodemap, 0); + if (rc) + goto out; + rc = libxl_cpumap_to_nodemap(CTX, suitable_cpumap, &suitable_nodemap); + if (rc) + goto out; + /* * If the minimum number of NUMA nodes is not explicitly specified * (i.e., min_nodes == 0), we try to figure out a sensible number of nodes @@ -317,10 +346,14 @@ int libxl__get_numa_candidate(libxl__gc *gc, else min_nodes = (min_cpus + cpus_per_node - 1) / cpus_per_node; } - if (min_nodes > nr_nodes) - min_nodes = nr_nodes; - if (!max_nodes || max_nodes > nr_nodes) - max_nodes = nr_nodes; + /* We also need to be sure we do not exceed the number of + * nodes we are allowed to use. */ + nr_suit_nodes = libxl_bitmap_count_set(&suitable_nodemap); + + if (min_nodes > nr_suit_nodes) + min_nodes = nr_suit_nodes; + if (!max_nodes || max_nodes > nr_suit_nodes) + max_nodes = nr_suit_nodes; if (min_nodes > max_nodes) { LOG(ERROR, "Inconsistent minimum or maximum number of guest nodes"); rc = ERROR_INVAL; @@ -353,12 +386,16 @@ int libxl__get_numa_candidate(libxl__gc *gc, * amount of free memory and number of cpus) and it can concur to * become our best placement iff it passes the check. */ - for (comb_ok = comb_init(gc, &comb_iter, nr_nodes, min_nodes); comb_ok; - comb_ok = comb_next(comb_iter, nr_nodes, min_nodes)) { + for (comb_ok = comb_init(gc, &comb_iter, nr_suit_nodes, min_nodes); + comb_ok; + comb_ok = comb_next(comb_iter, nr_suit_nodes, min_nodes)) { uint32_t nodes_free_memkb; int nodes_cpus; - comb_get_nodemap(comb_iter, &nodemap, min_nodes); + /* Get the nodemap for the combination, only considering + * suitable nodes. */ + comb_get_nodemap(comb_iter, &suitable_nodemap, + &nodemap, min_nodes); /* If there is not enough memory in this combination, skip it * and go generating the next one... */ @@ -367,7 +404,8 @@ int libxl__get_numa_candidate(libxl__gc *gc, continue; /* And the same applies if this combination is short in cpus */ - nodes_cpus = nodemap_to_nr_cpus(tinfo, nr_cpus, &nodemap); + nodes_cpus = nodemap_to_nr_cpus(tinfo, nr_cpus, suitable_cpumap, + &nodemap); if (min_cpus && nodes_cpus < min_cpus) continue; @@ -378,7 +416,7 @@ int libxl__get_numa_candidate(libxl__gc *gc, libxl__numa_candidate_put_nodemap(gc, &new_cndt, &nodemap); new_cndt.nr_vcpus = nodemap_to_nr_vcpus(gc, tinfo, &nodemap); new_cndt.free_memkb = nodes_free_memkb; - new_cndt.nr_nodes = min_nodes; + new_cndt.nr_nodes = libxl_bitmap_count_set(&nodemap); new_cndt.nr_cpus = nodes_cpus; /* @@ -392,8 +430,9 @@ int libxl__get_numa_candidate(libxl__gc *gc, LOG(DEBUG, "New best NUMA placement candidate found: " "nr_nodes=%d, nr_cpus=%d, nr_vcpus=%d, " - "free_memkb=%"PRIu32"", min_nodes, new_cndt.nr_cpus, - new_cndt.nr_vcpus, new_cndt.free_memkb / 1024); + "free_memkb=%"PRIu32"", new_cndt.nr_nodes, + new_cndt.nr_cpus, new_cndt.nr_vcpus, + new_cndt.free_memkb / 1024); libxl__numa_candidate_put_nodemap(gc, cndt_out, &nodemap); cndt_out->nr_vcpus = new_cndt.nr_vcpus; @@ -413,6 +452,7 @@ int libxl__get_numa_candidate(libxl__gc *gc, out: libxl_bitmap_dispose(&nodemap); + libxl_bitmap_dispose(&suitable_nodemap); libxl__numa_candidate_dispose(&new_cndt); libxl_numainfo_list_free(ninfo, nr_nodes); libxl_cputopology_list_free(tinfo, nr_cpus); |