(removed r...@hydra11.kio from CC)
On Tue, Jun 19, 2012 at 03:45:27PM -0700, Chegu Vinod wrote:
> From: root <r...@hydra11.kio>
>
> Changes since v1:
> ----------------
>
> - Use bitmap functions that are already in qemu (instead
> of cpu_set_t macro's)
> - Added a check for endvalue >= max_cpus.
> - Fix to address the round-robbing assignment (for the case
> when cpu's are not explicitly specified)
Tested-by: Eduardo Habkost <ehabk...@redhat.com>
It works as expected, now.
>
> Note: Continuing to use a new constant for
> allocation of the cpumask (max_cpus was
> not getting set early enough).
You could simply change the code so that the bitmaps are created only
after max_cpus is set.
Except for that, the rest of the patch looks OK, now.
>
[...]
> diff --git a/cpus.c b/cpus.c
> index b182b3d..89ce04d 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -36,6 +36,7 @@
> #include "cpus.h"
> #include "qtest.h"
> #include "main-loop.h"
> +#include "bitmap.h"
>
> #ifndef _WIN32
> #include "compatfd.h"
> @@ -1145,7 +1146,7 @@ void set_numa_modes(void)
>
> for (env = first_cpu; env != NULL; env = env->next_cpu) {
> for (i = 0; i < nb_numa_nodes; i++) {
> - if (node_cpumask[i] & (1 << env->cpu_index)) {
> + if (test_bit(env->cpu_index, node_cpumask[i])) {
> env->numa_node = i;
> }
> }
> diff --git a/hw/pc.c b/hw/pc.c
> index c7e9ab3..8800fc0 100644
> --- a/hw/pc.c
> +++ b/hw/pc.c
> @@ -48,6 +48,7 @@
> #include "memory.h"
> #include "exec-memory.h"
> #include "arch_init.h"
> +#include "bitmap.h"
>
> /* output Bochs bios info messages */
> //#define DEBUG_BIOS
> @@ -637,9 +638,10 @@ static void *bochs_bios_init(void)
> */
> numa_fw_cfg = g_malloc0((1 + max_cpus + nb_numa_nodes) * 8);
> numa_fw_cfg[0] = cpu_to_le64(nb_numa_nodes);
> +
> for (i = 0; i < max_cpus; i++) {
> for (j = 0; j < nb_numa_nodes; j++) {
> - if (node_cpumask[j] & (1 << i)) {
> + if (test_bit(i, node_cpumask[j])) {
> numa_fw_cfg[i + 1] = cpu_to_le64(j);
> break;
> }
> diff --git a/sysemu.h b/sysemu.h
> index bc2c788..6813115 100644
> --- a/sysemu.h
> +++ b/sysemu.h
> @@ -133,9 +133,10 @@ extern uint8_t qemu_extra_params_fw[2];
> extern QEMUClock *rtc_clock;
>
> #define MAX_NODES 64
> +#define MAX_CPUMASK_BITS 254
Why 254, specifically?
> extern int nb_numa_nodes;
> extern uint64_t node_mem[MAX_NODES];
> -extern uint64_t node_cpumask[MAX_NODES];
> +extern uint64_t *node_cpumask[MAX_NODES];
>
> #define MAX_OPTION_ROMS 16
> typedef struct QEMUOptionRom {
> diff --git a/vl.c b/vl.c
> index 1329c30..dd4ba75 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -28,6 +28,7 @@
> #include <errno.h>
> #include <sys/time.h>
> #include <zlib.h>
> +#include "bitmap.h"
>
> /* Needed early for CONFIG_BSD etc. */
> #include "config-host.h"
> @@ -240,7 +241,7 @@ QTAILQ_HEAD(, FWBootEntry) fw_boot_order =
> QTAILQ_HEAD_INITIALIZER(fw_boot_order
>
> int nb_numa_nodes;
> uint64_t node_mem[MAX_NODES];
> -uint64_t node_cpumask[MAX_NODES];
> +uint64_t *node_cpumask[MAX_NODES];
>
> uint8_t qemu_uuid[16];
>
> @@ -950,6 +951,9 @@ static void numa_add(const char *optarg)
> char *endptr;
> unsigned long long value, endvalue;
> int nodenr;
> + int i;
> +
> + value = endvalue = 0;
>
> optarg = get_opt_name(option, 128, optarg, ',') + 1;
> if (!strcmp(option, "node")) {
> @@ -970,27 +974,24 @@ static void numa_add(const char *optarg)
> }
> node_mem[nodenr] = sval;
> }
> - if (get_param_value(option, 128, "cpus", optarg) == 0) {
> - node_cpumask[nodenr] = 0;
> - } else {
> + if (get_param_value(option, 128, "cpus", optarg) != 0) {
> value = strtoull(option, &endptr, 10);
> - if (value >= 64) {
> - value = 63;
> - fprintf(stderr, "only 64 CPUs in NUMA mode supported.\n");
> + if (*endptr == '-') {
> + endvalue = strtoull(endptr+1, &endptr, 10);
> } else {
> - if (*endptr == '-') {
> - endvalue = strtoull(endptr+1, &endptr, 10);
> - if (endvalue >= 63) {
> - endvalue = 62;
> - fprintf(stderr,
> - "only 63 CPUs in NUMA mode supported.\n");
> - }
> - value = (2ULL << endvalue) - (1ULL << value);
> - } else {
> - value = 1ULL << value;
> - }
> + endvalue = value;
> + }
> +
> + if (endvalue >= max_cpus) {
> + endvalue = max_cpus - 1;
> + fprintf(stderr,
> + "A max of %d CPUs are supported in a guest on this
> host\n",
> + max_cpus);
> + }
> +
> + for (i = value; i <= endvalue; ++i) {
> + set_bit(i, node_cpumask[nodenr]);
> }
> - node_cpumask[nodenr] = value;
You changed behavior, here. Now the following command-line:
"qemu -numa node,nodeid=0,cpus=1 -numa node,nodeid=0,cpus=2"
will get both cpus 1 and 2 on node 0. Before your patch, node 0 would
get only CPU 2.
I think it is a desirable change, and the above command-line was already
ambiguous, but this could be documented in the patch description.
> }
> nb_numa_nodes++;
> }
> @@ -2331,7 +2332,8 @@ int main(int argc, char **argv, char **envp)
>
> for (i = 0; i < MAX_NODES; i++) {
> node_mem[i] = 0;
> - node_cpumask[i] = 0;
> + node_cpumask[i] = (unsigned long *) g_malloc0(MAX_CPUMASK_BITS);
You are allocating 254 bytes here, not 254 bits.
> + bitmap_zero(node_cpumask[i], MAX_CPUMASK_BITS);
> }
If MAX_CPUMASK_BITS is really going to be a constant (instead of using
max_cpus), you don't even need to allocate the bitmaps dynamically. They
could be static arrays.
>
> nb_numa_nodes = 0;
> @@ -3469,16 +3471,18 @@ int main(int argc, char **argv, char **envp)
> }
>
> for (i = 0; i < nb_numa_nodes; i++) {
> - if (node_cpumask[i] != 0)
> + if (!bitmap_empty(node_cpumask[i], MAX_CPUMASK_BITS)) {
> break;
> + }
> }
> +
> /* assigning the VCPUs round-robin is easier to implement, guest OSes
> * must cope with this anyway, because there are BIOSes out there in
> * real machines which also use this scheme.
> */
> if (i == nb_numa_nodes) {
> for (i = 0; i < max_cpus; i++) {
> - node_cpumask[i % nb_numa_nodes] |= 1 << i;
> + set_bit(i, node_cpumask[i % nb_numa_nodes]);
> }
> }
> }
> --
> 1.7.1
>
--
Eduardo
