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numa: make -numa parser dynamically allocate CPUs masks
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so it won't impose an additional limits on max_cpus limits
supported by different targets.

It removes global MAX_CPUMASK_BITS constant and need to
bump it up whenever max_cpus is being increased for
a target above MAX_CPUMASK_BITS value.

Use runtime max_cpus value instead to allocate sufficiently
sized node_cpu bitmasks in numa parser.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <1479466974-249781-1-git-send-email-imammedo@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
[ehabkost: Added asserts to ensure cpu_index < max_cpus]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
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Igor Mammedov authored and ehabkost committed Jan 12, 2017
1 parent 410e981 commit cdda201
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Showing 4 changed files with 15 additions and 20 deletions.
2 changes: 1 addition & 1 deletion include/sysemu/numa.h
Original file line number Diff line number Diff line change
Expand Up @@ -17,7 +17,7 @@ struct numa_addr_range {

typedef struct node_info {
uint64_t node_mem;
DECLARE_BITMAP(node_cpu, MAX_CPUMASK_BITS);
unsigned long *node_cpu;
struct HostMemoryBackend *node_memdev;
bool present;
QLIST_HEAD(, numa_addr_range) addr; /* List to store address ranges */
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7 changes: 0 additions & 7 deletions include/sysemu/sysemu.h
Original file line number Diff line number Diff line change
Expand Up @@ -168,13 +168,6 @@ extern int mem_prealloc;
#define MAX_NODES 128
#define NUMA_NODE_UNASSIGNED MAX_NODES

/* The following shall be true for all CPUs:
* cpu->cpu_index < max_cpus <= MAX_CPUMASK_BITS
*
* Note that cpu->get_arch_id() may be larger than MAX_CPUMASK_BITS.
*/
#define MAX_CPUMASK_BITS 288

#define MAX_OPTION_ROMS 16
typedef struct QEMUOptionRom {
const char *name;
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21 changes: 14 additions & 7 deletions numa.c
Original file line number Diff line number Diff line change
Expand Up @@ -266,20 +266,19 @@ static char *enumerate_cpus(unsigned long *cpus, int max_cpus)
static void validate_numa_cpus(void)
{
int i;
DECLARE_BITMAP(seen_cpus, MAX_CPUMASK_BITS);
unsigned long *seen_cpus = bitmap_new(max_cpus);

bitmap_zero(seen_cpus, MAX_CPUMASK_BITS);
for (i = 0; i < nb_numa_nodes; i++) {
if (bitmap_intersects(seen_cpus, numa_info[i].node_cpu,
MAX_CPUMASK_BITS)) {
if (bitmap_intersects(seen_cpus, numa_info[i].node_cpu, max_cpus)) {
bitmap_and(seen_cpus, seen_cpus,
numa_info[i].node_cpu, MAX_CPUMASK_BITS);
numa_info[i].node_cpu, max_cpus);
error_report("CPU(s) present in multiple NUMA nodes: %s",
enumerate_cpus(seen_cpus, max_cpus));
g_free(seen_cpus);
exit(EXIT_FAILURE);
}
bitmap_or(seen_cpus, seen_cpus,
numa_info[i].node_cpu, MAX_CPUMASK_BITS);
numa_info[i].node_cpu, max_cpus);
}

if (!bitmap_full(seen_cpus, max_cpus)) {
Expand All @@ -291,12 +290,17 @@ static void validate_numa_cpus(void)
"in NUMA config");
g_free(msg);
}
g_free(seen_cpus);
}

void parse_numa_opts(MachineClass *mc)
{
int i;

for (i = 0; i < MAX_NODES; i++) {
numa_info[i].node_cpu = bitmap_new(max_cpus);
}

if (qemu_opts_foreach(qemu_find_opts("numa"), parse_numa, NULL, NULL)) {
exit(1);
}
Expand Down Expand Up @@ -362,7 +366,7 @@ void parse_numa_opts(MachineClass *mc)
numa_set_mem_ranges();

for (i = 0; i < nb_numa_nodes; i++) {
if (!bitmap_empty(numa_info[i].node_cpu, MAX_CPUMASK_BITS)) {
if (!bitmap_empty(numa_info[i].node_cpu, max_cpus)) {
break;
}
}
Expand Down Expand Up @@ -397,6 +401,7 @@ void numa_post_machine_init(void)

CPU_FOREACH(cpu) {
for (i = 0; i < nb_numa_nodes; i++) {
assert(cpu->cpu_index < max_cpus);
if (test_bit(cpu->cpu_index, numa_info[i].node_cpu)) {
cpu->numa_node = i;
}
Expand Down Expand Up @@ -558,6 +563,8 @@ int numa_get_node_for_cpu(int idx)
{
int i;

assert(idx < max_cpus);

for (i = 0; i < nb_numa_nodes; i++) {
if (test_bit(idx, numa_info[i].node_cpu)) {
break;
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5 changes: 0 additions & 5 deletions vl.c
Original file line number Diff line number Diff line change
Expand Up @@ -1277,11 +1277,6 @@ static void smp_parse(QemuOpts *opts)

max_cpus = qemu_opt_get_number(opts, "maxcpus", cpus);

if (max_cpus > MAX_CPUMASK_BITS) {
error_report("unsupported number of maxcpus");
exit(1);
}

if (max_cpus < cpus) {
error_report("maxcpus must be equal to or greater than smp");
exit(1);
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