haproxy/src/cpu_topo.c
Willy Tarreau 4a44d592ae BUG/MINOR: cpu-topo: check the correct variable for NULL after malloc()
We were testing ha_cpu_topo instead of ha_cpu_clusters after an allocation,
making the check ineffective.

No backport is needed.
2025-04-12 18:23:29 +02:00

1883 lines
58 KiB
C

#define _GNU_SOURCE
#include <dirent.h>
#include <sched.h>
#include <string.h>
#include <unistd.h>
#include <haproxy/api.h>
#include <haproxy/cfgparse.h>
#include <haproxy/cpuset.h>
#include <haproxy/cpu_topo.h>
#include <haproxy/global.h>
#include <haproxy/log.h>
#include <haproxy/tools.h>
/* for cpu_set.flags below */
#define CPU_SET_FL_NONE 0x0000
#define CPU_SET_FL_DO_RESET 0x0001
/* CPU topology information, ha_cpuset_size() entries, allocated at boot */
int cpu_topo_maxcpus = -1; // max number of CPUs supported by OS/haproxy
int cpu_topo_lastcpu = -1; // last supposed online CPU (no need to look beyond)
struct ha_cpu_topo *ha_cpu_topo = NULL;
struct ha_cpu_cluster *ha_cpu_clusters = NULL;
struct cpu_map *cpu_map;
/* non-zero if we're certain that taskset or similar was used to force CPUs */
int cpu_mask_forced = 0;
/* "cpu-set" global configuration */
struct cpu_set_cfg {
uint flags; // CPU_SET_FL_XXX above
/* CPU numbers to accept / reject */
struct hap_cpuset only_cpus;
struct hap_cpuset drop_cpus;
/* node numbers to accept / reject */
struct hap_cpuset only_nodes;
struct hap_cpuset drop_nodes;
/* cluster numbers to accept / reject */
struct hap_cpuset only_clusters;
struct hap_cpuset drop_clusters;
/* core numbers to accept / reject */
struct hap_cpuset only_cores;
struct hap_cpuset drop_cores;
/* thread numbers to accept / reject */
struct hap_cpuset only_threads;
struct hap_cpuset drop_threads;
} cpu_set_cfg;
/* CPU policy choice */
static int cpu_policy = 1; // "first-usable-node"
/* list of CPU policies for "cpu-policy". The default one is the first one. */
static int cpu_policy_first_usable_node(int policy, int tmin, int tmax, int gmin, int gmax, char **err);
static int cpu_policy_group_by_cluster(int policy, int tmin, int tmax, int gmin, int gmax, char **err);
static int cpu_policy_performance(int policy, int tmin, int tmax, int gmin, int gmax, char **err);
static int cpu_policy_efficiency(int policy, int tmin, int tmax, int gmin, int gmax, char **err);
static int cpu_policy_resource(int policy, int tmin, int tmax, int gmin, int gmax, char **err);
static struct ha_cpu_policy ha_cpu_policy[] = {
{ .name = "none", .desc = "use all available CPUs", .fct = NULL },
{ .name = "first-usable-node", .desc = "use only first usable node if nbthreads not set", .fct = cpu_policy_first_usable_node, .arg = 0 },
{ .name = "group-by-cluster", .desc = "make one thread group per core cluster", .fct = cpu_policy_group_by_cluster , .arg = 1 },
{ .name = "group-by-2-clusters",.desc = "make one thread group per 2 core clusters", .fct = cpu_policy_group_by_cluster , .arg = 2 },
{ .name = "group-by-3-clusters",.desc = "make one thread group per 3 core clusters", .fct = cpu_policy_group_by_cluster , .arg = 3 },
{ .name = "group-by-4-clusters",.desc = "make one thread group per 4 core clusters", .fct = cpu_policy_group_by_cluster , .arg = 4 },
{ .name = "performance", .desc = "make one thread group per perf. core cluster", .fct = cpu_policy_performance , .arg = 0 },
{ .name = "efficiency", .desc = "make one thread group per eff. core cluster", .fct = cpu_policy_efficiency , .arg = 0 },
{ .name = "resource", .desc = "make one thread group from the smallest cluster", .fct = cpu_policy_resource , .arg = 0 },
{ 0 } /* end */
};
/* Detects CPUs that are online on the system. It may rely on FS access (e.g.
* /sys on Linux). Returns the number of CPUs detected or 0 if the detection
* failed.
*/
int ha_cpuset_detect_online(struct hap_cpuset *set)
{
#if defined(__linux__)
ha_cpuset_zero(set);
/* contains a list of CPUs in the format <low>[-<high>][,...] */
if (read_line_to_trash("%s/cpu/online", NUMA_DETECT_SYSTEM_SYSFS_PATH) >= 0) {
const char *parse_cpu_set_args[2] = { trash.area, "\0" };
if (parse_cpu_set(parse_cpu_set_args, set, NULL) != 0)
ha_cpuset_zero(set);
}
#elif defined(__FreeBSD__)
struct hap_cpuset node_cpu_set;
int ndomains, domain;
size_t len = sizeof(ndomains);
ha_cpuset_zero(set);
/* retrieve the union of NUMA nodes as online CPUs */
if (sysctlbyname("vm.ndomains", &ndomains, &len, NULL, 0) == 0) {
BUG_ON(ndomains > MAXMEMDOM);
for (domain = 0; domain < ndomains; domain++) {
ha_cpuset_zero(&node_cpu_set);
if (cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_DOMAIN, domain,
sizeof(node_cpu_set.cpuset), &node_cpu_set.cpuset) == -1)
continue;
ha_cpuset_or(set, &node_cpu_set);
}
}
#else // !__linux__, !__FreeBSD__
ha_cpuset_zero(set);
#endif
return ha_cpuset_count(set);
}
/* Detects the CPUs that will be used based on the ones the process is bound to
* at boot. The principle is the following: all CPUs from the boot cpuset will
* be used since we don't know upfront how individual threads will be mapped to
* groups and CPUs.
*
* Returns non-zero on success, zero on failure. Note that it may not be
* performed in the function above because some calls may rely on other items
* being allocated (e.g. trash).
*/
int cpu_detect_usable(void)
{
struct hap_cpuset boot_set = { };
int cpu;
if (!(cpu_set_cfg.flags & CPU_SET_FL_DO_RESET)) {
/* update the list with the CPUs currently bound to the current process */
ha_cpuset_detect_bound(&boot_set);
/* remove the known-excluded CPUs */
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++)
if (!ha_cpuset_isset(&boot_set, cpu))
ha_cpu_topo[cpu].st |= HA_CPU_F_EXCLUDED;
}
/* remove CPUs in the drop-cpu set or not in the only-cpu set */
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++) {
if ( ha_cpuset_isset(&cpu_set_cfg.drop_cpus, cpu) ||
!ha_cpuset_isset(&cpu_set_cfg.only_cpus, cpu))
ha_cpu_topo[cpu].st |= HA_CPU_F_DONT_USE;
}
/* Update the list of currently offline CPUs. Normally it's a subset
* of the unbound ones, but we cannot infer anything if we don't have
* the info so we only update what we know. We take this opportunity
* for detecting that some online CPUs are not bound, indicating that
* taskset or equivalent was used.
*/
if (ha_cpuset_detect_online(&boot_set)) {
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++) {
if (!ha_cpuset_isset(&boot_set, cpu)) {
ha_cpu_topo[cpu].st |= HA_CPU_F_OFFLINE;
} else {
cpu_topo_lastcpu = cpu;
if (ha_cpu_topo[cpu].st & HA_CPU_F_EXCLUDED)
cpu_mask_forced = 1;
}
}
}
return 0;
}
/* Detects CPUs that are bound to the current process. Returns the number of
* CPUs detected or 0 if the detection failed.
*/
int ha_cpuset_detect_bound(struct hap_cpuset *set)
{
ha_cpuset_zero(set);
/* detect bound CPUs depending on the OS's API */
if (0
#if defined(__linux__)
|| sched_getaffinity(0, sizeof(set->cpuset), &set->cpuset) != 0
#elif defined(__FreeBSD__)
|| cpuset_getaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_PID, -1, sizeof(set->cpuset), &set->cpuset) != 0
#else
|| 1 // unhandled platform
#endif
) {
/* detection failed */
return 0;
}
return ha_cpuset_count(set);
}
/* Returns true if at least one cpu-map directive was configured, otherwise
* false.
*/
int cpu_map_configured(void)
{
int grp, thr;
for (grp = 0; grp < MAX_TGROUPS; grp++) {
for (thr = 0; thr < MAX_THREADS_PER_GROUP; thr++)
if (ha_cpuset_count(&cpu_map[grp].thread[thr]))
return 1;
}
return 0;
}
/* Dump the CPU topology <topo> for up to cpu_topo_maxcpus CPUs for
* debugging purposes. Offline CPUs are skipped.
*/
void cpu_dump_topology(const struct ha_cpu_topo *topo)
{
int has_smt = 0;
int cpu, lvl;
int grp, thr;
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].th_cnt > 1) {
has_smt = 1;
break;
}
}
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].st & HA_CPU_F_OFFLINE)
continue;
printf("[%s] cpu=%3d pk=%02d no=%02d cl=%03d(%03d)",
(ha_cpu_topo[cpu].st & HA_CPU_F_EXCL_MASK) ? "----" : "keep",
ha_cpu_topo[cpu].idx,
ha_cpu_topo[cpu].pk_id,
ha_cpu_topo[cpu].no_id,
ha_cpu_topo[cpu].cl_gid,
ha_cpu_topo[cpu].cl_lid);
/* list only relevant cache levels */
for (lvl = 4; lvl >= 0; lvl--) {
if (ha_cpu_topo[cpu].ca_id[lvl] < 0)
continue;
printf(lvl < 3 ? " l%d=%02d" : " l%d=%03d", lvl, ha_cpu_topo[cpu].ca_id[lvl]);
}
printf(" ts=%03d capa=%d",
ha_cpu_topo[cpu].ts_id,
ha_cpu_topo[cpu].capa);
if (has_smt) {
if (ha_cpu_topo[cpu].th_cnt > 1)
printf(" smt=%d/%d",
ha_cpu_topo[cpu].th_id,
ha_cpu_topo[cpu].th_cnt);
else
printf(" smt=%d",
ha_cpu_topo[cpu].th_cnt);
}
putchar('\n');
}
printf("CPU clusters:\n");
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++) {
if (!ha_cpu_clusters[cpu].nb_cpu)
continue;
printf(" %3u cpus=%3u cores=%3u capa=%u\n",
cpu, ha_cpu_clusters[cpu].nb_cpu,
ha_cpu_clusters[cpu].nb_cores,
ha_cpu_clusters[cpu].capa);
}
printf("Thread CPU Bindings:\n Tgrp/Thr Tid CPU set\n");
for (grp = 0; grp < global.nbtgroups; grp++) {
int first, last;
int min, max;
first = ha_tgroup_info[grp].base;
last = ha_tgroup_info[grp].base + ha_tgroup_info[grp].count - 1;
min = max = -1;
for (thr = first; thr <= last; thr++) {
if (min < 0)
min = thr;
if (thr == last ||
!ha_cpuset_isequal(&cpu_map[grp].thread[min - first],
&cpu_map[grp].thread[thr + 1 - first]))
max = thr;
if (min >= 0 && max >= 0) {
/* we have a range */
char str[1024];
int len = 0;
int len2;
/* print group/thread-range */
len += snprintf(str + len, sizeof(str) - len, "%d/%d", grp + 1, min - first + 1);
if (min != max)
len += snprintf(str + len, sizeof(str) - len, "-%d", max - first + 1);
/* max len is 8: "64/64-64", plus 2 spaces = 10 */
while (len < 10) {
str[len++] = ' ';
str[len] = 0;
}
/* append global thread range */
len += snprintf(str + len, sizeof(str) - len, "%d", min + 1);
if (min != max)
len += snprintf(str + len, sizeof(str) - len, "-%d", max + 1);
/* max len is 9: "4096-4096", plus 2 spaces = 11, plus 10 initial chars = 21 */
while (len < 21) {
str[len++] = ' ';
str[len] = 0;
}
if (ha_cpuset_count(&cpu_map[grp].thread[thr - first]))
len += snprintf(str + len, sizeof(str) - len, "%d: ", ha_cpuset_count(&cpu_map[grp].thread[thr - first]));
len2 = print_cpu_set(str + len, sizeof(str) - len, &cpu_map[grp].thread[thr - first]);
if (len2 > sizeof(str) - len)
snprintf(str + len, sizeof(str) - len, "<too_large>");
else if (len2 == 0)
snprintf(str + len, sizeof(str) - len, "<all>");
printf(" %s\n", str);
min = max = -1;
}
}
}
}
/* function used by qsort to re-arrange CPUs by index only, to restore original
* ordering.
*/
int _cmp_cpu_index(const void *a, const void *b)
{
const struct ha_cpu_topo *l = (const struct ha_cpu_topo *)a;
const struct ha_cpu_topo *r = (const struct ha_cpu_topo *)b;
/* next, IDX, so that SMT ordering is preserved */
if (l->idx >= 0 && l->idx < r->idx)
return -1;
if (l->idx > r->idx && r->idx >= 0)
return 1;
/* exactly the same (e.g. absent, should not happen) */
return 0;
}
/* function used by qsort to compare two hwcpus and arrange them by vicinity
* only. -1 says a<b, 1 says a>b. The goal is to arrange the closest CPUs
* together, preferring locality over performance in order to keep latency
* as low as possible, so that when picking a fixed number of threads, the
* closest ones are used in priority. It's also used to help arranging groups
* at the end.
*/
int _cmp_cpu_locality(const void *a, const void *b)
{
const struct ha_cpu_topo *l = (const struct ha_cpu_topo *)a;
const struct ha_cpu_topo *r = (const struct ha_cpu_topo *)b;
/* first, online vs offline */
if (!(l->st & HA_CPU_F_EXCL_MASK) && (r->st & HA_CPU_F_EXCL_MASK))
return -1;
if (!(r->st & HA_CPU_F_EXCL_MASK) && (l->st & HA_CPU_F_EXCL_MASK))
return 1;
/* next, package ID */
if (l->pk_id >= 0 && l->pk_id < r->pk_id)
return -1;
if (l->pk_id > r->pk_id && r->pk_id >= 0)
return 1;
/* next, node ID */
if (l->no_id >= 0 && l->no_id < r->no_id)
return -1;
if (l->no_id > r->no_id && r->no_id >= 0)
return 1;
/* next, L4 */
if (l->ca_id[4] >= 0 && l->ca_id[4] < r->ca_id[4])
return -1;
if (l->ca_id[4] > r->ca_id[4] && r->ca_id[4] >= 0)
return 1;
/* next, L3 */
if (l->ca_id[3] >= 0 && l->ca_id[3] < r->ca_id[3])
return -1;
if (l->ca_id[3] > r->ca_id[3] && r->ca_id[3] >= 0)
return 1;
/* next, cluster */
if (l->cl_gid >= 0 && l->cl_gid < r->cl_gid)
return -1;
if (l->cl_gid > r->cl_gid && r->cl_gid >= 0)
return 1;
/* next, L2 */
if (l->ca_id[2] >= 0 && l->ca_id[2] < r->ca_id[2])
return -1;
if (l->ca_id[2] > r->ca_id[2] && r->ca_id[2] >= 0)
return 1;
/* next, thread set */
if (l->ts_id >= 0 && l->ts_id < r->ts_id)
return -1;
if (l->ts_id > r->ts_id && r->ts_id >= 0)
return 1;
/* next, L1 */
if (l->ca_id[1] >= 0 && l->ca_id[1] < r->ca_id[1])
return -1;
if (l->ca_id[1] > r->ca_id[1] && r->ca_id[1] >= 0)
return 1;
/* next, L0 */
if (l->ca_id[0] >= 0 && l->ca_id[0] < r->ca_id[0])
return -1;
if (l->ca_id[0] > r->ca_id[0] && r->ca_id[0] >= 0)
return 1;
/* next, IDX, so that SMT ordering is preserved */
if (l->idx >= 0 && l->idx < r->idx)
return -1;
if (l->idx > r->idx && r->idx >= 0)
return 1;
/* exactly the same (e.g. absent) */
return 0;
}
/* function used by qsort to compare two hwcpus and arrange them by vicinity
* then capacity. -1 says a<b, 1 says a>b. The goal is to detect different
* CPU capacities among clusters.
*/
int _cmp_cpu_cluster_capa(const void *a, const void *b)
{
const struct ha_cpu_topo *l = (const struct ha_cpu_topo *)a;
const struct ha_cpu_topo *r = (const struct ha_cpu_topo *)b;
/* first, online vs offline */
if (!(l->st & HA_CPU_F_EXCL_MASK) && (r->st & HA_CPU_F_EXCL_MASK))
return -1;
if (!(r->st & HA_CPU_F_EXCL_MASK) && (l->st & HA_CPU_F_EXCL_MASK))
return 1;
/* next, package ID */
if (l->pk_id >= 0 && l->pk_id < r->pk_id)
return -1;
if (l->pk_id > r->pk_id && r->pk_id >= 0)
return 1;
/* next, node ID */
if (l->no_id >= 0 && l->no_id < r->no_id)
return -1;
if (l->no_id > r->no_id && r->no_id >= 0)
return 1;
/* next, L4 */
if (l->ca_id[4] >= 0 && l->ca_id[4] < r->ca_id[4])
return -1;
if (l->ca_id[4] > r->ca_id[4] && r->ca_id[4] >= 0)
return 1;
/* next, L3 */
if (l->ca_id[3] >= 0 && l->ca_id[3] < r->ca_id[3])
return -1;
if (l->ca_id[3] > r->ca_id[3] && r->ca_id[3] >= 0)
return 1;
/* next, cluster */
if (l->cl_gid >= 0 && l->cl_gid < r->cl_gid)
return -1;
if (l->cl_gid > r->cl_gid && r->cl_gid >= 0)
return 1;
/* Same cluster. For CPU capacity, we tolerate a +/- 5% margin however
* so that if some values come from measurement we don't end up
* reorganizing everything.
*/
if (l->capa > 0 && (int)l->capa * 19 > (int)r->capa * 20)
return -1;
if (r->capa > 0 && (int)l->capa * 20 < (int)r->capa * 19)
return 1;
/* next, L2 */
if (l->ca_id[2] >= 0 && l->ca_id[2] < r->ca_id[2])
return -1;
if (l->ca_id[2] > r->ca_id[2] && r->ca_id[2] >= 0)
return 1;
/* next, thread set */
if (l->ts_id >= 0 && l->ts_id < r->ts_id)
return -1;
if (l->ts_id > r->ts_id && r->ts_id >= 0)
return 1;
/* next, L1 */
if (l->ca_id[1] >= 0 && l->ca_id[1] < r->ca_id[1])
return -1;
if (l->ca_id[1] > r->ca_id[1] && r->ca_id[1] >= 0)
return 1;
/* next, L0 */
if (l->ca_id[0] >= 0 && l->ca_id[0] < r->ca_id[0])
return -1;
if (l->ca_id[0] > r->ca_id[0] && r->ca_id[0] >= 0)
return 1;
/* next, IDX, so that SMT ordering is preserved */
if (l->idx >= 0 && l->idx < r->idx)
return -1;
if (l->idx > r->idx && r->idx >= 0)
return 1;
/* exactly the same */
return 0;
}
/* function used by qsort to compare two hwcpus and arrange them by cluster to
* make sure no cluster crosses L3 boundaries. -1 says a<b, 1 says a>b. It's
* only used during topology detection.
*/
int _cmp_cpu_cluster(const void *a, const void *b)
{
const struct ha_cpu_topo *l = (const struct ha_cpu_topo *)a;
const struct ha_cpu_topo *r = (const struct ha_cpu_topo *)b;
/* first, online vs offline */
if (!(l->st & HA_CPU_F_EXCL_MASK) && (r->st & HA_CPU_F_EXCL_MASK))
return -1;
if (!(r->st & HA_CPU_F_EXCL_MASK) && (l->st & HA_CPU_F_EXCL_MASK))
return 1;
/* next, cluster */
if (l->cl_gid >= 0 && l->cl_gid < r->cl_gid)
return -1;
if (l->cl_gid > r->cl_gid && r->cl_gid >= 0)
return 1;
/* next, package ID */
if (l->pk_id >= 0 && l->pk_id < r->pk_id)
return -1;
if (l->pk_id > r->pk_id && r->pk_id >= 0)
return 1;
/* next, node ID */
if (l->no_id >= 0 && l->no_id < r->no_id)
return -1;
if (l->no_id > r->no_id && r->no_id >= 0)
return 1;
/* next, L3 */
if (l->ca_id[3] >= 0 && l->ca_id[3] < r->ca_id[3])
return -1;
if (l->ca_id[3] > r->ca_id[3] && r->ca_id[3] >= 0)
return 1;
/* if no L3, then L2 */
if (l->ca_id[2] >= 0 && l->ca_id[2] < r->ca_id[2])
return -1;
if (l->ca_id[2] > r->ca_id[2] && r->ca_id[2] >= 0)
return 1;
/* next, IDX, so that SMT ordering is preserved */
if (l->idx >= 0 && l->idx < r->idx)
return -1;
if (l->idx > r->idx && r->idx >= 0)
return 1;
/* exactly the same (e.g. absent) */
return 0;
}
/* re-order a CPU topology array by CPU index only. This is mostly used before
* listing CPUs regardless of their characteristics.
*/
void cpu_reorder_by_index(struct ha_cpu_topo *topo, int entries)
{
qsort(topo, entries, sizeof(*topo), _cmp_cpu_index);
}
/* re-order a CPU topology array by locality to help form groups. */
void cpu_reorder_by_locality(struct ha_cpu_topo *topo, int entries)
{
qsort(topo, entries, sizeof(*topo), _cmp_cpu_locality);
}
/* re-order a CPU topology array by cluster id. */
void cpu_reorder_by_cluster(struct ha_cpu_topo *topo, int entries)
{
qsort(topo, entries, sizeof(*topo), _cmp_cpu_cluster);
}
/* re-order a CPU topology array by locality and capacity to detect clusters. */
void cpu_reorder_by_cluster_capa(struct ha_cpu_topo *topo, int entries)
{
qsort(topo, entries, sizeof(*topo), _cmp_cpu_cluster_capa);
}
/* functions below act on ha_cpu_cluster structs */
/* function used by qsort to reorder clusters by index */
int _cmp_cluster_index(const void *a, const void *b)
{
const struct ha_cpu_cluster *l = (const struct ha_cpu_cluster *)a;
const struct ha_cpu_cluster *r = (const struct ha_cpu_cluster *)b;
return l->idx - r->idx;
}
/* function used by qsort to order clustes by reverse capacity */
int _cmp_cluster_capa(const void *a, const void *b)
{
const struct ha_cpu_cluster *l = (const struct ha_cpu_cluster *)a;
const struct ha_cpu_cluster *r = (const struct ha_cpu_cluster *)b;
return r->capa - l->capa;
}
/* re-order a cluster array by cluster index only */
void cpu_cluster_reorder_by_index(struct ha_cpu_cluster *clusters, int entries)
{
qsort(clusters, entries, sizeof(*clusters), _cmp_cluster_index);
}
/* re-order a CPU topology array by locality and capacity to detect clusters. */
void cpu_cluster_reorder_by_capa(struct ha_cpu_cluster *clusters, int entries)
{
qsort(clusters, entries, sizeof(*clusters), _cmp_cluster_capa);
}
/* returns an optimal maxcpus for the current system. It will take into
* account what is reported by the OS, if any, otherwise will fall back
* to the cpuset size, which serves as an upper limit in any case.
*/
static int cpu_topo_get_maxcpus(void)
{
int abs_max = ha_cpuset_size();
#if defined(_SC_NPROCESSORS_CONF)
int n = (int)sysconf(_SC_NPROCESSORS_CONF);
if (n > 0 && n <= abs_max)
return n;
#endif
return abs_max;
}
/* This function is responsible for trying to fill in the missing info after
* topology detection and making sure we don't leave any ID at -1, but rather
* we assign unused ones.
*/
void cpu_fixup_topology(void)
{
struct hap_cpuset cpuset;
int cpu, cpu2;
int curr_id, prev_id;
int min_id, neg;
int cl_cpu, small_cl;
/* fill the package id, node id and thread_id. First we'll build a bitmap
* of all unassigned ones so that we can spot the lowest unassigned one
* and assign it to those currently set to -1.
*/
/* package id */
ha_cpuset_zero(&cpuset);
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++)
ha_cpuset_set(&cpuset, cpu);
for (cpu = neg = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].pk_id < 0)
neg++;
else
ha_cpuset_clr(&cpuset, ha_cpu_topo[cpu].pk_id);
}
/* get the first unused pkg id */
min_id = ha_cpuset_ffs(&cpuset) - 1;
for (cpu = 0; neg && cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].pk_id < 0) {
ha_cpu_topo[cpu].pk_id = min_id;
neg--;
}
}
/* node id */
ha_cpuset_zero(&cpuset);
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++)
ha_cpuset_set(&cpuset, cpu);
for (cpu = neg = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].no_id < 0)
neg++;
else
ha_cpuset_clr(&cpuset, ha_cpu_topo[cpu].no_id);
}
/* get the first unused node id */
min_id = ha_cpuset_ffs(&cpuset) - 1;
for (cpu = 0; neg && cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].no_id < 0) {
ha_cpu_topo[cpu].no_id = min_id;
neg--;
}
}
/* thread id */
ha_cpuset_zero(&cpuset);
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++)
ha_cpuset_set(&cpuset, cpu);
for (cpu = neg = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].th_id < 0)
neg++;
else
ha_cpuset_clr(&cpuset, ha_cpu_topo[cpu].th_id);
}
/* get the first unused thr id */
min_id = ha_cpuset_ffs(&cpuset) - 1;
for (cpu = 0; neg && cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].th_id < 0) {
ha_cpu_topo[cpu].th_id = min_id;
ha_cpu_topo[cpu].th_cnt = min_id + 1;
neg--;
}
}
/* Some machines (typically ARM cortex A76 and Neoverse-N1) report 1
* cluster per pair of cores due to the internal architecture. While
* this can occasionally make sense (i.e. big.LITTLE etc), when there
* are many clusters of few cores, this is totally pointless. Here
* we'll check if there are at least 4 2-cpu clusters, and if so, all
* the 2-cpu clusters will be cancelled.
*/
cpu_reorder_by_cluster(ha_cpu_topo, cpu_topo_maxcpus);
curr_id = -1;
cl_cpu = small_cl = 0;
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].cl_gid < 0)
continue;
if (ha_cpu_topo[cpu].st & HA_CPU_F_EXCL_MASK)
continue;
if (ha_cpu_topo[cpu].cl_gid != curr_id) {
if (curr_id >= 0 && cl_cpu <= 2)
small_cl++;
cl_cpu = 0;
curr_id = ha_cpu_topo[cpu].cl_gid;
}
cl_cpu++;
}
/* last one */
if (cl_cpu && cl_cpu <= 2)
small_cl++;
/* here we have the number of small clusters (<=2 cpu) in small_cl */
if (small_cl >= 4) {
for (cpu = cpu2 = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].cl_gid < 0)
continue;
if (ha_cpu_topo[cpu].st & HA_CPU_F_EXCL_MASK)
continue;
if (ha_cpu_topo[cpu].cl_gid != curr_id) {
if (curr_id >= 0 && cl_cpu <= 2) {
/* small cluster found for curr_id */
while (cpu2 < cpu) {
if (ha_cpu_topo[cpu2].cl_gid == curr_id)
ha_cpu_topo[cpu2].cl_gid = -1;
cpu2++;
}
}
cl_cpu = 0;
cpu2 = cpu;
curr_id = ha_cpu_topo[cpu].cl_gid;
}
cl_cpu++;
}
/* handle the last cluster */
while (curr_id >= 0 && cl_cpu <= 2 && cpu2 < cpu) {
if (ha_cpu_topo[cpu2].cl_gid == curr_id)
ha_cpu_topo[cpu2].cl_gid = -1;
cpu2++;
}
}
cpu_reorder_by_index(ha_cpu_topo, cpu_topo_maxcpus);
/* assign capacity if not filled, based on the number of threads on the
* core: in a same package, SMT-capable cores are generally those
* optimized for performers while non-SMT ones are generally those
* optimized for efficiency. We'll reflect that by assigning 100 and 50
* respectively to those.
*/
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].capa < 0)
ha_cpu_topo[cpu].capa = (ha_cpu_topo[cpu].th_cnt > 1) ? 100 : 50;
}
/* First, on some machines, L3 is not reported. But some also don't
* have L3. However, no L3 when there are more than 2 L2 is quite
* unheard of, and while we don't really care about firing 2 groups for
* 2 L2, we'd rather avoid this if there are 8! In this case we'll add
* an L3 instance to fix the situation.
*/
cpu_reorder_by_locality(ha_cpu_topo, cpu_topo_maxcpus);
prev_id = -2; // make sure it cannot match even unassigned ones
curr_id = -1;
for (cpu = cpu2 = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].ca_id[3] >= 0)
continue;
/* L3 not assigned, count L2 instances */
if (!cpu ||
(ha_cpu_topo[cpu].pk_id != ha_cpu_topo[cpu-1].pk_id) ||
(ha_cpu_topo[cpu].no_id != ha_cpu_topo[cpu-1].no_id) ||
(ha_cpu_topo[cpu].ca_id[4] != ha_cpu_topo[cpu-1].ca_id[4])) {
curr_id = 0;
prev_id = -2;
cpu2 = cpu;
}
else if (ha_cpu_topo[cpu].ca_id[2] != prev_id) {
curr_id++;
if (curr_id >= 2) {
/* let's assign L3 id to zero for all those.
* We can go till the end since we'll just skip
* them on next passes above.
*/
for (; cpu2 <= cpu_topo_lastcpu; cpu2++) {
if (ha_cpu_topo[cpu2].ca_id[3] < 0 &&
ha_cpu_topo[cpu2].pk_id == ha_cpu_topo[cpu].pk_id &&
ha_cpu_topo[cpu2].no_id == ha_cpu_topo[cpu].no_id &&
ha_cpu_topo[cpu2].ca_id[4] == ha_cpu_topo[cpu].ca_id[4])
ha_cpu_topo[cpu2].ca_id[3] = 0;
}
}
}
}
/* let's make core numbers contiguous and per (pkg,node) as well, as
* holes may exist due to SMT.
*/
prev_id = -2; // make sure it cannot match even unassigned ones
curr_id = -1;
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
/* renumber clusters and assign unassigne ones at the same
* time. For this, we'll compare pkg/die/llc with the last
* CPU's and verify if we need to create a new cluster ID.
* Note that some platforms don't report cache. The value is
* local to the pkg+node combination so that we reset it when
* changing.
*/
if (!cpu ||
(ha_cpu_topo[cpu].pk_id != ha_cpu_topo[cpu-1].pk_id) ||
(ha_cpu_topo[cpu].no_id != ha_cpu_topo[cpu-1].no_id)) {
curr_id = 0;
}
else if (ha_cpu_topo[cpu].ts_id != prev_id ||
ha_cpu_topo[cpu].ca_id[4] != ha_cpu_topo[cpu-1].ca_id[4] ||
(ha_cpu_topo[cpu].ca_id[4] < 0 && // no l4 ? check L3
((ha_cpu_topo[cpu].ca_id[3] != ha_cpu_topo[cpu-1].ca_id[3]) ||
(ha_cpu_topo[cpu].ca_id[3] < 0 && // no l3 ? check L2
(ha_cpu_topo[cpu].ca_id[2] != ha_cpu_topo[cpu-1].ca_id[2]))))) {
curr_id++;
}
prev_id = ha_cpu_topo[cpu].ts_id;
ha_cpu_topo[cpu].ts_id = curr_id;
}
cpu_reorder_by_index(ha_cpu_topo, cpu_topo_maxcpus);
}
/* This function is responsible for composing clusters based on existing info
* on the CPU topology.
*/
void cpu_compose_clusters(void)
{
int cpu, core;
int curr_gid, prev_gid;
int curr_lid, prev_lid;
/* Now we'll sort CPUs by topology/cluster/capacity and assign cluster
* IDs to those that don't have one, based on the die/pkg/lcc, and
* double-check that capacity within a cluster doesn't vary by +/- 5%,
* otherwise it indicates different clusters (typically big.little).
*/
cpu_reorder_by_cluster_capa(ha_cpu_topo, cpu_topo_maxcpus);
prev_gid = prev_lid = -2; // make sure it cannot match even unassigned ones
curr_gid = curr_lid = -1;
core = -1;
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
/* renumber clusters and assign unassigned ones at the same
* time. For this, we'll compare pkg/die/llc with the last
* CPU's and verify if we need to create a new cluster ID.
* Note that some platforms don't report cache. The locao value
* is local to the pkg+node combination so that we reset it
* when changing, contrary to the global one which grows.
*/
if (!cpu ||
(ha_cpu_topo[cpu].pk_id != ha_cpu_topo[cpu-1].pk_id) ||
(ha_cpu_topo[cpu].no_id != ha_cpu_topo[cpu-1].no_id)) {
curr_gid++;
curr_lid = 0;
core = -1;
}
else if (ha_cpu_topo[cpu].cl_gid != prev_gid ||
ha_cpu_topo[cpu].ca_id[4] != ha_cpu_topo[cpu-1].ca_id[4] ||
(ha_cpu_topo[cpu].ca_id[4] < 0 && // no l4 ? check L3
((ha_cpu_topo[cpu].ca_id[3] != ha_cpu_topo[cpu-1].ca_id[3]) ||
(ha_cpu_topo[cpu].ca_id[3] < 0 && // no l3 ? check L2
(ha_cpu_topo[cpu].ca_id[2] != ha_cpu_topo[cpu-1].ca_id[2])))) ||
(ha_cpu_topo[cpu].capa > 0 && ha_cpu_topo[cpu-1].capa > 0 &&
(ha_cpu_topo[cpu].capa * 100 < ha_cpu_topo[cpu-1].capa * 95 ||
ha_cpu_topo[cpu].capa * 95 > ha_cpu_topo[cpu-1].capa * 100))) {
curr_gid++;
curr_lid++;
}
prev_gid = ha_cpu_topo[cpu].cl_gid;
prev_lid = ha_cpu_topo[cpu].cl_lid;
ha_cpu_topo[cpu].cl_gid = curr_gid;
ha_cpu_topo[cpu].cl_lid = curr_lid;
/* update per-cluster info */
if (!(ha_cpu_topo[cpu].st & HA_CPU_F_EXCL_MASK)) {
ha_cpu_clusters[curr_gid].nb_cpu++;
if (ha_cpu_topo[cpu].ts_id != core) {
/* new core for this cluster */
ha_cpu_clusters[curr_gid].nb_cores++;
ha_cpu_clusters[curr_gid].capa += ha_cpu_topo[cpu].capa;
core = ha_cpu_topo[cpu].ts_id;
} else {
/* tests show that it's reasonable to expect
* ~+33% for an extra thread on the same core.
*/
ha_cpu_clusters[curr_gid].capa += ha_cpu_topo[cpu].capa / 3;
}
}
}
cpu_reorder_by_index(ha_cpu_topo, cpu_topo_maxcpus);
}
/* apply remaining topology-based cpu set restrictions */
void cpu_refine_cpusets(void)
{
int cpu;
/* remove CPUs in the drop-node set or not in the only-node set */
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if ( ha_cpuset_isset(&cpu_set_cfg.drop_nodes, ha_cpu_topo[cpu].no_id) ||
!ha_cpuset_isset(&cpu_set_cfg.only_nodes, ha_cpu_topo[cpu].no_id))
ha_cpu_topo[cpu].st |= HA_CPU_F_DONT_USE;
}
/* remove CPUs in the drop-cluster set or not in the only-cluster set */
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if ( ha_cpuset_isset(&cpu_set_cfg.drop_clusters, ha_cpu_topo[cpu].cl_lid) ||
!ha_cpuset_isset(&cpu_set_cfg.only_clusters, ha_cpu_topo[cpu].cl_lid))
ha_cpu_topo[cpu].st |= HA_CPU_F_DONT_USE;
}
/* remove CPUs in the drop-core set or not in the only-core set */
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if ( ha_cpuset_isset(&cpu_set_cfg.drop_cores, ha_cpu_topo[cpu].ts_id) ||
!ha_cpuset_isset(&cpu_set_cfg.only_cores, ha_cpu_topo[cpu].ts_id))
ha_cpu_topo[cpu].st |= HA_CPU_F_DONT_USE;
}
/* remove CPUs in the drop-thread set or not in the only-thread set */
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if ( ha_cpuset_isset(&cpu_set_cfg.drop_threads, ha_cpu_topo[cpu].th_id) ||
!ha_cpuset_isset(&cpu_set_cfg.only_threads, ha_cpu_topo[cpu].th_id))
ha_cpu_topo[cpu].st |= HA_CPU_F_DONT_USE;
}
}
/* the "first-usable-node" cpu-policy: historical one
* - does nothing if numa_cpu_mapping is not set
* - does nothing if nbthread is set
* - does nothing if the set of CPUs had been set manually using taskset
* - does nothing if the first node couldn't be determined
* Otherwise ignores all CPUs not on the first node.
*/
static int cpu_policy_first_usable_node(int policy, int tmin, int tmax, int gmin, int gmax, char **err)
{
struct hap_cpuset node_cpu_set;
int first_node_id = -1;
int second_node_id = -1;
int cpu;
int cpu_count;
int grp, thr;
if (!global.numa_cpu_mapping)
return 0;
if (global.nbthread)
return 0;
if (cpu_mask_forced)
return 0;
/* determine first and second nodes with usable CPUs */
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].st & HA_CPU_F_EXCL_MASK)
continue;
if (ha_cpu_topo[cpu].no_id >= 0 &&
ha_cpu_topo[cpu].no_id != first_node_id) {
if (first_node_id < 0)
first_node_id = ha_cpu_topo[cpu].no_id;
else {
second_node_id = ha_cpu_topo[cpu].no_id;
break;
}
}
}
/* no information found on a second node */
if (second_node_id < 0)
return 0;
/* ignore all CPUs of other nodes, count the remaining valid ones,
* and make a CPU set of them.
*/
ha_cpuset_zero(&node_cpu_set);
for (cpu = cpu_count = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].no_id != first_node_id)
ha_cpu_topo[cpu].st |= HA_CPU_F_IGNORED;
else if (!(ha_cpu_topo[cpu].st & HA_CPU_F_EXCL_MASK)) {
ha_cpuset_set(&node_cpu_set, ha_cpu_topo[cpu].idx);
cpu_count++;
}
}
/* assign all threads of all thread groups to this node */
for (grp = 0; grp < MAX_TGROUPS; grp++)
for (thr = 0; thr < MAX_THREADS_PER_GROUP; thr++)
ha_cpuset_assign(&cpu_map[grp].thread[thr], &node_cpu_set);
if (tmin <= cpu_count && cpu_count < tmax)
tmax = cpu_count;
ha_diag_warning("Multi-socket cpu detected, automatically binding on active CPUs of '%d' (%u active cpu(s))\n", first_node_id, cpu_count);
if (!global.nbthread)
global.nbthread = tmax;
return 0;
}
/* the "group-by-cluster" cpu-policy:
* - does nothing if nbthread or thread-groups are set
* - otherwise tries to create one thread-group per cluster, with as many
* threads as CPUs in the cluster, and bind all the threads of this group
* to all the CPUs of the cluster.
* Also implements the variants "group-by-2-clusters", "group-by-3-clusters"
* and "group-by-4-clusters".
*/
static int cpu_policy_group_by_cluster(int policy, int tmin, int tmax, int gmin, int gmax, char **err)
{
struct hap_cpuset node_cpu_set;
int cpu, cpu_start;
int cpu_count;
int cid, lcid;
int thr_per_grp, nb_grp;
int thr;
int div;
if (global.nbthread)
return 0;
if (global.nbtgroups)
return 0;
/* iterate over each new cluster */
lcid = -1;
cpu_start = 0;
/* used as a divisor of clusters*/
div = ha_cpu_policy[policy].arg;
div = div ? div : 1;
while (global.nbtgroups < MAX_TGROUPS && global.nbthread < MAX_THREADS) {
ha_cpuset_zero(&node_cpu_set);
cid = -1; cpu_count = 0;
for (cpu = cpu_start; cpu <= cpu_topo_lastcpu; cpu++) {
/* skip disabled and already visited CPUs */
if (ha_cpu_topo[cpu].st & HA_CPU_F_EXCL_MASK)
continue;
if ((ha_cpu_topo[cpu].cl_gid / div) <= lcid)
continue;
if (cid < 0) {
cid = ha_cpu_topo[cpu].cl_gid / div;
cpu_start = cpu + 1;
}
else if (cid != ha_cpu_topo[cpu].cl_gid / div)
continue;
/* make a mask of all of this cluster's CPUs */
ha_cpuset_set(&node_cpu_set, ha_cpu_topo[cpu].idx);
cpu_count++;
}
/* now cid = next cluster_id or -1 if none; cpu_count is the
* number of CPUs in this cluster, and cpu_start is the next
* cpu to restart from to scan for new clusters.
*/
if (cid < 0 || !cpu_count)
break;
/* check that we're still within limits. If there are too many
* CPUs but enough groups left, we'll try to make more smaller
* groups, of the closest size each.
*/
nb_grp = (cpu_count + MAX_THREADS_PER_GROUP - 1) / MAX_THREADS_PER_GROUP;
if (nb_grp > MAX_TGROUPS - global.nbtgroups)
nb_grp = MAX_TGROUPS - global.nbtgroups;
thr_per_grp = (cpu_count + nb_grp - 1) / nb_grp;
if (thr_per_grp > MAX_THREADS_PER_GROUP)
thr_per_grp = MAX_THREADS_PER_GROUP;
while (nb_grp && cpu_count > 0) {
/* create at most thr_per_grp threads */
if (thr_per_grp > cpu_count)
thr_per_grp = cpu_count;
if (thr_per_grp + global.nbthread > MAX_THREADS)
thr_per_grp = MAX_THREADS - global.nbthread;
/* let's create the new thread group */
ha_tgroup_info[global.nbtgroups].base = global.nbthread;
ha_tgroup_info[global.nbtgroups].count = thr_per_grp;
/* assign to this group the required number of threads */
for (thr = 0; thr < thr_per_grp; thr++) {
ha_thread_info[thr + global.nbthread].tgid = global.nbtgroups + 1;
ha_thread_info[thr + global.nbthread].tg = &ha_tgroup_info[global.nbtgroups];
ha_thread_info[thr + global.nbthread].tg_ctx = &ha_tgroup_ctx[global.nbtgroups];
/* map these threads to all the CPUs */
ha_cpuset_assign(&cpu_map[global.nbtgroups].thread[thr], &node_cpu_set);
}
cpu_count -= thr_per_grp;
global.nbthread += thr_per_grp;
global.nbtgroups++;
if (global.nbtgroups >= MAX_TGROUPS || global.nbthread >= MAX_THREADS)
break;
}
lcid = cid; // last cluster_id
}
if (global.nbthread)
ha_diag_warning("Created %d threads split into %d groups\n", global.nbthread, global.nbtgroups);
else
ha_diag_warning("Could not determine any CPU cluster\n");
return 0;
}
/* the "performance" cpu-policy:
* - does nothing if nbthread or thread-groups are set
* - eliminates clusters whose total capacity is below half of others
* - tries to create one thread-group per cluster, with as many
* threads as CPUs in the cluster, and bind all the threads of
* this group to all the CPUs of the cluster.
*/
static int cpu_policy_performance(int policy, int tmin, int tmax, int gmin, int gmax, char **err)
{
int cpu, cluster;
int capa;
if (global.nbthread || global.nbtgroups)
return 0;
/* sort clusters by reverse capacity */
cpu_cluster_reorder_by_capa(ha_cpu_clusters, cpu_topo_maxcpus);
capa = 0;
for (cluster = 0; cluster < cpu_topo_maxcpus; cluster++) {
if (capa && ha_cpu_clusters[cluster].capa < capa / 2) {
/* This cluster is more than twice as slow as the
* previous one, we're not interested in using it.
*/
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].cl_gid == ha_cpu_clusters[cluster].idx)
ha_cpu_topo[cpu].st |= HA_CPU_F_IGNORED;
}
}
else
capa = ha_cpu_clusters[cluster].capa;
}
cpu_cluster_reorder_by_index(ha_cpu_clusters, cpu_topo_maxcpus);
/* and finish using the group-by-cluster strategy */
return cpu_policy_group_by_cluster(policy, tmin, tmax, gmin, gmax, err);
}
/* the "efficiency" cpu-policy:
* - does nothing if nbthread or thread-groups are set
* - eliminates clusters whose total capacity is above half of others
* - tries to create one thread-group per cluster, with as many
* threads as CPUs in the cluster, and bind all the threads of
* this group to all the CPUs of the cluster.
*/
static int cpu_policy_efficiency(int policy, int tmin, int tmax, int gmin, int gmax, char **err)
{
int cpu, cluster;
int capa;
if (global.nbthread || global.nbtgroups)
return 0;
/* sort clusters by reverse capacity */
cpu_cluster_reorder_by_capa(ha_cpu_clusters, cpu_topo_maxcpus);
capa = 0;
for (cluster = cpu_topo_maxcpus - 1; cluster >= 0; cluster--) {
if (capa && ha_cpu_clusters[cluster].capa > capa * 2) {
/* This cluster is more than twice as fast as the
* previous one, we're not interested in using it.
*/
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].cl_gid == ha_cpu_clusters[cluster].idx)
ha_cpu_topo[cpu].st |= HA_CPU_F_IGNORED;
}
}
else
capa = ha_cpu_clusters[cluster].capa;
}
cpu_cluster_reorder_by_index(ha_cpu_clusters, cpu_topo_maxcpus);
/* and finish using the group-by-cluster strategy */
return cpu_policy_group_by_cluster(policy, tmin, tmax, gmin, gmax, err);
}
/* the "resource" cpu-policy:
* - does nothing if nbthread or thread-groups are set
* - only keeps the smallest cluster.
*/
static int cpu_policy_resource(int policy, int tmin, int tmax, int gmin, int gmax, char **err)
{
int cpu, cluster;
int capa;
if (global.nbthread || global.nbtgroups)
return 0;
/* sort clusters by reverse capacity */
cpu_cluster_reorder_by_capa(ha_cpu_clusters, cpu_topo_maxcpus);
capa = 0;
for (cluster = cpu_topo_maxcpus - 1; cluster >= 0; cluster--) {
if (capa) {
/* we already have a cluster, let's disable this
* one.
*/
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
if (ha_cpu_topo[cpu].cl_gid == ha_cpu_clusters[cluster].idx)
ha_cpu_topo[cpu].st |= HA_CPU_F_IGNORED;
}
}
else
capa = ha_cpu_clusters[cluster].capa;
}
cpu_cluster_reorder_by_index(ha_cpu_clusters, cpu_topo_maxcpus);
/* and finish using the group-by-cluster strategy */
return cpu_policy_group_by_cluster(policy, tmin, tmax, gmin, gmax, err);
}
/* apply the chosen CPU policy if no cpu-map was forced. Returns < 0 on failure
* with a message in *err that must be freed by the caller if non-null.
*/
int cpu_apply_policy(int tmin, int tmax, int gmin, int gmax, char **err)
{
*err = NULL;
if (cpu_map_configured()) {
/* nothing to do */
return 0;
}
if (!ha_cpu_policy[cpu_policy].fct) {
/* nothing to do */
return 0;
}
if (ha_cpu_policy[cpu_policy].fct(cpu_policy, tmin, tmax, gmin, gmax, err) < 0)
return -1;
return 0;
}
/* CPU topology detection below, OS-specific */
#if defined(__linux__)
/* detect the CPU topology based on info in /sys */
int cpu_detect_topology(void)
{
const char *parse_cpu_set_args[2];
struct ha_cpu_topo cpu_id = { }; /* all zeroes */
struct hap_cpuset node_cpu_set;
struct dirent *de;
int no_cache, no_topo, no_capa, no_clust, no_pkg;
int no_cppc, no_freq;
DIR *dir;
int cpu;
/* now let's only focus on bound CPUs to learn more about their
* topology, their siblings, their cache affinity etc. We can stop
* at lastcpu which matches the ID of the last known bound CPU
* when it's set. We'll pre-assign and auto-increment indexes for
* thread_set_id, cluster_id, l1/l2/l3 id, etc. We don't revisit entries
* already filled from the list provided by another CPU.
*/
if (!is_dir_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu"))
goto skip_cpu;
/* detect the presence of some kernel-specific fields */
no_cache = no_topo = no_capa = no_clust = no_pkg = no_freq = no_cppc = -1;
for (cpu = 0; cpu <= cpu_topo_lastcpu; cpu++) {
struct hap_cpuset siblings_list = { };
struct hap_cpuset cpus_list;
int next_level = 1; // assume L1 if unknown
int idx, level;
int cpu2;
if (ha_cpu_topo[cpu].st & HA_CPU_F_OFFLINE)
continue;
if (!is_dir_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d", cpu))
continue;
/* First, let's check the cache hierarchy. On systems exposing
* it, index0 generally is the L1D cache, index1 the L1I, index2
* the L2 and index3 the L3. But sometimes L1I/D are reversed,
* and some CPUs also have L0 or L4. Maybe some heterogeneous
* SoCs even have inconsistent levels between clusters... Thus
* we'll scan all entries that we can find for each CPU and
* assign levels based on what is reported. The types generally
* are "Data", "Instruction", "Unified". We just ignore inst if
* found.
*/
if (no_cache < 0)
no_cache = !is_dir_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/cache", cpu);
if (no_cache)
goto skip_cache;
for (idx = 0; idx < 10; idx++) {
if (!is_dir_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/cache/index%d", cpu, idx))
break;
if (read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH
"/cpu/cpu%d/cache/index%d/type", cpu, idx) >= 0 &&
strcmp(trash.area, "Instruction") == 0)
continue;
level = next_level;
if (read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH
"/cpu/cpu%d/cache/index%d/level", cpu, idx) >= 0) {
level = atoi(trash.area);
next_level = level + 1;
}
if (level < 0 || level > 4)
continue; // level out of bounds
if (ha_cpu_topo[cpu].ca_id[level] >= 0)
continue; // already filled
if (read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH
"/cpu/cpu%d/cache/index%d/shared_cpu_list", cpu, idx) >= 0) {
parse_cpu_set_args[0] = trash.area;
parse_cpu_set_args[1] = "\0";
if (parse_cpu_set(parse_cpu_set_args, &cpus_list, NULL) == 0) {
for (cpu2 = 0; cpu2 <= cpu_topo_lastcpu; cpu2++) {
if (ha_cpuset_isset(&cpus_list, cpu2))
ha_cpu_topo[cpu2].ca_id[level] = cpu_id.ca_id[level];
}
cpu_id.ca_id[level]++;
}
}
}
skip_cache:
if (no_topo < 0)
no_topo = !is_dir_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology", cpu);
if (no_topo)
goto skip_topo;
/* Now let's try to get more info about how the cores are
* arranged in packages, clusters, cores, threads etc. It
* overlaps a bit with the cache above, but as not all systems
* provide all of these, they're quite complementary in fact.
*/
/* thread siblings list will allow to figure which CPU threads
* share the same cores, and also to tell apart cores that
* support SMT from those which do not. When mixed, generally
* the ones with SMT are big cores and the ones without are the
* small ones. We also read the entry if the cluster_id is not
* known because we'll have to compare both values.
*/
if ((ha_cpu_topo[cpu].ts_id < 0 || ha_cpu_topo[cpu].cl_gid < 0) &&
read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/thread_siblings_list", cpu) >= 0) {
parse_cpu_set_args[0] = trash.area;
parse_cpu_set_args[1] = "\0";
if (parse_cpu_set(parse_cpu_set_args, &siblings_list, NULL) == 0) {
int sib_id = 0;
cpu_id.th_cnt = ha_cpuset_count(&siblings_list);
for (cpu2 = 0; cpu2 <= cpu_topo_lastcpu; cpu2++) {
if (ha_cpuset_isset(&siblings_list, cpu2)) {
ha_cpu_topo[cpu2].ts_id = cpu_id.ts_id;
ha_cpu_topo[cpu2].th_cnt = cpu_id.th_cnt;
ha_cpu_topo[cpu2].th_id = sib_id++;
}
}
cpu_id.ts_id++;
}
}
/* clusters of cores when they exist, can be smaller and more
* precise than core lists (e.g. big.little), otherwise use
* core lists as a fall back, which may also have been used
* above as a fallback for package but we don't care here. We
* only consider these values if there's more than one CPU per
* cluster (some kernels such as 6.1 report one cluster per CPU).
* Note that we purposely ignore clusters that are reportedly
* equal to the siblings list, because some machines report one
* distinct cluster per *core* (e.g. some armv7 and intel 14900).
*/
if (no_clust < 0) {
no_clust = !is_file_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/cluster_cpus_list", cpu) &&
!is_file_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/core_siblings_list", cpu);
}
if (!no_clust && ha_cpu_topo[cpu].cl_gid < 0 &&
(read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/cluster_cpus_list", cpu) >= 0 ||
read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/core_siblings_list", cpu) >= 0)) {
parse_cpu_set_args[0] = trash.area;
parse_cpu_set_args[1] = "\0";
if (parse_cpu_set(parse_cpu_set_args, &cpus_list, NULL) == 0 && ha_cpuset_count(&cpus_list) > 1 &&
(memcmp(&cpus_list, &siblings_list, sizeof(cpus_list)) != 0)) {
for (cpu2 = 0; cpu2 <= cpu_topo_lastcpu; cpu2++) {
if (ha_cpuset_isset(&cpus_list, cpu2)) {
ha_cpu_topo[cpu2].cl_lid = cpu_id.cl_lid;
ha_cpu_topo[cpu2].cl_gid = cpu_id.cl_gid;
}
}
cpu_id.cl_lid++;
cpu_id.cl_gid++;
}
}
/* package CPUs list, like nodes, are generally a hard limit
* for groups, which must not span over multiple of them. On
* some systems, the package_cpus_list is not always provided,
* so we may first fall back to core_siblings_list which also
* exists, then to the physical package id from each CPU, whose
* number starts at 0. The first one is preferred because it
* provides a list in a single read().
*/
if (no_pkg < 0) {
no_pkg = !is_file_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/package_cpus_list", cpu) &&
!is_file_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/core_siblings_list", cpu);
}
if (!no_pkg && ha_cpu_topo[cpu].pk_id < 0 &&
(read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/package_cpus_list", cpu) >= 0 ||
read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/core_siblings_list", cpu) >= 0)) {
parse_cpu_set_args[0] = trash.area;
parse_cpu_set_args[1] = "\0";
if (parse_cpu_set(parse_cpu_set_args, &cpus_list, NULL) == 0) {
for (cpu2 = 0; cpu2 <= cpu_topo_lastcpu; cpu2++) {
if (ha_cpuset_isset(&cpus_list, cpu2))
ha_cpu_topo[cpu2].pk_id = cpu_id.pk_id;
}
cpu_id.pk_id++;
}
}
if (ha_cpu_topo[cpu].pk_id < 0 &&
read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/topology/physical_package_id", cpu) >= 0) {
if (trash.data)
ha_cpu_topo[cpu].pk_id = str2uic(trash.area);
}
skip_topo:
if (no_capa < 0)
no_capa = !is_file_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/cpu_capacity", cpu);
/* CPU capacity is a relative notion to compare little and big
* cores. Usually the values encountered in field set the big
* CPU's nominal capacity to 1024 and the other ones below.
*/
if (!no_capa && ha_cpu_topo[cpu].capa < 0 &&
read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/cpu_capacity", cpu) >= 0) {
if (trash.data)
ha_cpu_topo[cpu].capa = str2uic(trash.area);
}
/* When cpu_capacity is not available, sometimes acpi_cppc is
* available on servers to provide an equivalent metric allowing
* to distinguish big from small cores. Values as low as 15 and
* as high as 260 were seen there. Note that only nominal_perf
* is trustable, as nominal_freq may return zero. It's also
* more reliable than the max cpufreq values because it doesn't
* seem to take into account the die quality. However, acpi_cppc
* can be super slow on some systems (5ms per access noticed on
* a 64-core EPYC), making haproxy literally take seconds to
* start just due to this. Thus we start with cpufreq and fall
* back to acpi_cppc. If it becomes an issue, we could imagine
* forcing the value to all members of the same core and even
* cluster. Since the frequency alone is not a good criterion
* to qualify the CPU quality (perf vs efficiency core), instead
* we rely on the thread count to gauge if it's a performant or
* an efficient core, and we major performant cores' capacity
* by 50% (shown to be roughly correct on modern CPUs).
*/
if (no_freq < 0)
no_freq = !is_dir_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/cpufreq", cpu);
if (!no_freq && ha_cpu_topo[cpu].capa < 0 &&
read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/cpufreq/scaling_max_freq", cpu) >= 0) {
/* This is in kHz, turn it to MHz to stay below 32k */
if (trash.data) {
ha_cpu_topo[cpu].capa = (str2uic(trash.area) + 999U) / 1000U;
if (ha_cpu_topo[cpu].th_cnt > 1)
ha_cpu_topo[cpu].capa = ha_cpu_topo[cpu].capa * 3 / 2;
}
}
if (no_cppc < 0)
no_cppc = !is_dir_present(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/acpi_cppc", cpu);
if (!no_cppc && ha_cpu_topo[cpu].capa < 0 &&
read_line_to_trash(NUMA_DETECT_SYSTEM_SYSFS_PATH "/cpu/cpu%d/acpi_cppc/nominal_perf", cpu) >= 0) {
if (trash.data)
ha_cpu_topo[cpu].capa = str2uic(trash.area);
}
}
skip_cpu:
/* Now locate NUMA node IDs if any */
dir = opendir(NUMA_DETECT_SYSTEM_SYSFS_PATH "/node");
if (dir) {
while ((de = readdir(dir))) {
long node_id;
char *endptr;
/* dir name must start with "node" prefix */
if (strncmp(de->d_name, "node", 4) != 0)
continue;
/* dir name must be at least 5 characters long */
if (!de->d_name[4])
continue;
/* dir name must end with a non-negative numeric id */
node_id = strtol(&de->d_name[4], &endptr, 10);
if (*endptr || node_id < 0)
continue;
/* all tests succeeded, it's in the form "node%d" */
if (read_line_to_trash("%s/node/%s/cpulist", NUMA_DETECT_SYSTEM_SYSFS_PATH, de->d_name) >= 0) {
parse_cpu_set_args[0] = trash.area;
parse_cpu_set_args[1] = "\0";
if (parse_cpu_set(parse_cpu_set_args, &node_cpu_set, NULL) == 0) {
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++)
if (ha_cpuset_isset(&node_cpu_set, cpu))
ha_cpu_topo[cpu].no_id = node_id;
}
}
}
/* done */
closedir(dir);
}
return 1;
}
#elif defined(__FreeBSD__)
int cpu_detect_topology(void)
{
struct hap_cpuset node_cpu_set;
int ndomains, domain, cpu;
size_t len = sizeof(ndomains);
/* Try to detect NUMA nodes */
if (sysctlbyname("vm.ndomains", &ndomains, &len, NULL, 0) == 0) {
BUG_ON(ndomains > MAXMEMDOM);
/* For each domain we'll reference the domain ID in the belonging
* CPUs.
*/
for (domain = 0; domain < ndomains; domain++) {
ha_cpuset_zero(&node_cpu_set);
if (cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_DOMAIN, domain,
sizeof(node_cpu_set.cpuset), &node_cpu_set.cpuset) == -1)
continue;
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++)
if (ha_cpuset_isset(&node_cpu_set, cpu))
ha_cpu_topo[cpu].no_id = domain;
}
}
return 1;
}
#else // !__linux__, !__FreeBSD__
int cpu_detect_topology(void)
{
return 1;
}
#endif // OS-specific cpu_detect_topology()
/* Parse the "cpu-set" global directive, which takes action names and
* optional values, and fills the cpu_set structure above.
*/
static int cfg_parse_cpu_set(char **args, int section_type, struct proxy *curpx,
const struct proxy *defpx, const char *file, int line,
char **err)
{
const char *cpu_set_str[2] = { "", "" };
struct hap_cpuset tmp_cpuset = { };
int arg;
for (arg = 1; *args[arg]; arg++) {
if (strcmp(args[arg], "reset") == 0) {
/* reset the excluded CPUs first (undo "taskset") */
cpu_set_cfg.flags |= CPU_SET_FL_DO_RESET;
cpu_mask_forced = 0;
}
else if (strcmp(args[arg], "drop-cpu") == 0 || strcmp(args[arg], "only-cpu") == 0) {
if (!*args[arg + 1]) {
memprintf(err, "missing CPU set");
goto parse_err;
}
cpu_set_str[0] = args[arg + 1];
if (parse_cpu_set(cpu_set_str, &tmp_cpuset, err) != 0)
goto parse_err;
if (*args[arg] == 'd') // cpus to drop
ha_cpuset_or(&cpu_set_cfg.drop_cpus, &tmp_cpuset);
else // cpus to keep
ha_cpuset_and(&cpu_set_cfg.only_cpus, &tmp_cpuset);
arg++;
}
else if (strcmp(args[arg], "drop-node") == 0 || strcmp(args[arg], "only-node") == 0) {
if (!*args[arg + 1]) {
memprintf(err, "missing node set");
goto parse_err;
}
cpu_set_str[0] = args[arg + 1];
if (parse_cpu_set(cpu_set_str, &tmp_cpuset, err) != 0)
goto parse_err;
if (*args[arg] == 'd') // nodes to drop
ha_cpuset_or(&cpu_set_cfg.drop_nodes, &tmp_cpuset);
else // nodes to keep
ha_cpuset_and(&cpu_set_cfg.only_nodes, &tmp_cpuset);
arg++;
}
else if (strcmp(args[arg], "drop-cluster") == 0 || strcmp(args[arg], "only-cluster") == 0) {
if (!*args[arg + 1]) {
memprintf(err, "missing cluster set");
goto parse_err;
}
cpu_set_str[0] = args[arg + 1];
if (parse_cpu_set(cpu_set_str, &tmp_cpuset, err) != 0)
goto parse_err;
if (*args[arg] == 'd') // clusters to drop
ha_cpuset_or(&cpu_set_cfg.drop_clusters, &tmp_cpuset);
else // clusters to keep
ha_cpuset_and(&cpu_set_cfg.only_clusters, &tmp_cpuset);
arg++;
}
else if (strcmp(args[arg], "drop-core") == 0 || strcmp(args[arg], "only-core") == 0) {
if (!*args[arg + 1]) {
memprintf(err, "missing core set");
goto parse_err;
}
cpu_set_str[0] = args[arg + 1];
if (parse_cpu_set(cpu_set_str, &tmp_cpuset, err) != 0)
goto parse_err;
if (*args[arg] == 'd') // cores to drop
ha_cpuset_or(&cpu_set_cfg.drop_cores, &tmp_cpuset);
else // cores to keep
ha_cpuset_and(&cpu_set_cfg.only_cores, &tmp_cpuset);
arg++;
}
else if (strcmp(args[arg], "drop-thread") == 0 || strcmp(args[arg], "only-thread") == 0) {
if (!*args[arg + 1]) {
memprintf(err, "missing thread set");
goto parse_err;
}
cpu_set_str[0] = args[arg + 1];
if (parse_cpu_set(cpu_set_str, &tmp_cpuset, err) != 0)
goto parse_err;
if (*args[arg] == 'd') // threads to drop
ha_cpuset_or(&cpu_set_cfg.drop_threads, &tmp_cpuset);
else // threads to keep
ha_cpuset_and(&cpu_set_cfg.only_threads, &tmp_cpuset);
arg++;
}
else {
/* fall back with default error message */
memprintf(err, "'%s' passed an unknown directive '%s'", args[0], args[arg]);
goto leave_with_err;
}
}
if (arg == 1) {
memprintf(err, "'%s' requires a directive and an optional value", args[0]);
goto leave_with_err;
}
/* all done */
return 0;
parse_err:
/* displays args[0] and args[arg] followed by *err so as to remind the
* option name, the sub-directive and the reported error.
*/
memprintf(err, "'%s %s': %s\n.", args[0], args[arg], *err);
goto leave;
leave_with_err:
/* complete with supported directives */
memprintf(err, "%s (only 'reset', 'only-cpu', 'drop-cpu', 'only-node', 'drop-node', 'only-cluster', 'drop-cluster', 'only-core', 'drop-core', 'only-thread', 'drop-thread' supported).", *err);
leave:
return -1;
}
/* Parse the "cpu-policy" global directive, which takes the name of one of the
* ha_cpu_policy[] names, and sets the associated index in cpu_policy.
*/
static int cfg_parse_cpu_policy(char **args, int section_type, struct proxy *curpx,
const struct proxy *defpx, const char *file, int line,
char **err)
{
int i;
if (too_many_args(1, args, err, NULL))
return -1;
for (i = 0; ha_cpu_policy[i].name; i++) {
if (strcmp(args[1], ha_cpu_policy[i].name) == 0) {
cpu_policy = i;
return 0;
}
}
memprintf(err, "'%s' passed an unknown CPU policy '%s'. Supported values are:", args[0], args[1]);
for (i = 0; ha_cpu_policy[i].name; i++) {
memprintf(err, "%s%s '%s' (%s)%s", *err,
(i > 0 && ha_cpu_policy[i+1].name) ? "" : " and",
ha_cpu_policy[i].name,
ha_cpu_policy[i].desc,
(ha_cpu_policy[i+1].name) ? "," : ".\n");
}
return -1;
}
/* Allocates everything needed to store CPU topology at boot.
* Returns non-zero on success, zero on failure.
*/
static int cpu_topo_alloc(void)
{
int cpu;
cpu_topo_maxcpus = cpu_topo_get_maxcpus();
cpu_topo_lastcpu = cpu_topo_maxcpus - 1;
cpu_map = calloc(MAX_TGROUPS, sizeof(*cpu_map));
if (!cpu_map)
return 0;
/* allocate the structures used to store CPU topology info */
ha_cpu_topo = (struct ha_cpu_topo*)malloc(cpu_topo_maxcpus * sizeof(*ha_cpu_topo));
if (!ha_cpu_topo)
return 0;
/* allocate the structures used to store CPU topology info */
ha_cpu_clusters = (struct ha_cpu_cluster*)malloc(cpu_topo_maxcpus * sizeof(*ha_cpu_clusters));
if (!ha_cpu_clusters)
return 0;
/* preset all fields to -1 except the index and the state flags which
* are assumed to all be bound and online unless detected otherwise.
* Also set all cluster idx to their respective index.
*/
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++) {
memset(&ha_cpu_topo[cpu], 0xff, sizeof(*ha_cpu_topo));
ha_cpu_topo[cpu].st = 0;
ha_cpu_topo[cpu].idx = cpu;
memset(&ha_cpu_clusters[cpu], 0x0, sizeof(*ha_cpu_clusters));
ha_cpu_clusters[cpu].idx = cpu;
}
/* pre-inizialize the configured CPU sets */
ha_cpuset_zero(&cpu_set_cfg.drop_cpus);
ha_cpuset_zero(&cpu_set_cfg.only_cpus);
ha_cpuset_zero(&cpu_set_cfg.drop_nodes);
ha_cpuset_zero(&cpu_set_cfg.only_nodes);
ha_cpuset_zero(&cpu_set_cfg.drop_clusters);
ha_cpuset_zero(&cpu_set_cfg.only_clusters);
ha_cpuset_zero(&cpu_set_cfg.drop_cores);
ha_cpuset_zero(&cpu_set_cfg.only_cores);
ha_cpuset_zero(&cpu_set_cfg.drop_threads);
ha_cpuset_zero(&cpu_set_cfg.only_threads);
/* preset all CPUs in the "only-XXX" sets */
for (cpu = 0; cpu < cpu_topo_maxcpus; cpu++) {
ha_cpuset_set(&cpu_set_cfg.only_cpus, cpu);
ha_cpuset_set(&cpu_set_cfg.only_nodes, cpu);
ha_cpuset_set(&cpu_set_cfg.only_clusters, cpu);
ha_cpuset_set(&cpu_set_cfg.only_cores, cpu);
ha_cpuset_set(&cpu_set_cfg.only_threads, cpu);
}
return 1;
}
static void cpu_topo_deinit(void)
{
ha_free(&ha_cpu_clusters);
ha_free(&ha_cpu_topo);
ha_free(&cpu_map);
}
INITCALL0(STG_ALLOC, cpu_topo_alloc);
REGISTER_POST_DEINIT(cpu_topo_deinit);
/* config keyword parsers */
static struct cfg_kw_list cfg_kws = {ILH, {
{ CFG_GLOBAL, "cpu-policy", cfg_parse_cpu_policy, 0 },
{ CFG_GLOBAL, "cpu-set", cfg_parse_cpu_set, 0 },
{ 0, NULL, NULL }
}};
INITCALL1(STG_REGISTER, cfg_register_keywords, &cfg_kws);