v2: introduce -numa command line option

Signed-off-by Andre Przywara <[email protected]>

# HG changeset patch
# User Andre Przywara <[email protected]> # Date 1229425990 -3600
# Node ID 6690ab0a34fdedaebbfe1068dfe7351734e8a1d7 # Parent 4271a7547668e4b02cae88e66c936d9cacab624e add -numa command line option

diff -r 4271a7547668 -r 6690ab0a34fd sysemu.h

vl.c +41 -0

@@ -4065,6 +4072,7 @@ enum {
     QEMU_OPTION_usb,
     QEMU_OPTION_usbdevice,
     QEMU_OPTION_smp,
+    QEMU_OPTION_numa,
     QEMU_OPTION_vnc,
     QEMU_OPTION_no_acpi,
     QEMU_OPTION_curses,

@@ -4171,6 +4179,7 @@ static const QEMUOption qemu_options[] =
     { "win2k-hack", 0, QEMU_OPTION_win2k_hack },
     { "usbdevice", HAS_ARG, QEMU_OPTION_usbdevice },
     { "smp", HAS_ARG, QEMU_OPTION_smp },
+    { "numa", HAS_ARG, QEMU_OPTION_numa},
     { "vnc", HAS_ARG, QEMU_OPTION_vnc },
 #ifdef CONFIG_CURSES
     { "curses", 0, QEMU_OPTION_curses },

@@ -4456,6 +4465,94 @@ static void termsig_setup(void)
 }
 
 #endif
+
+#define PARSE_FLAG_BITMASK   1
+#define PARSE_FLAG_SUFFIX    2
+
+static int parse_to_array(const char *arg, uint64_t *array,
+    char delim, int maxentries, int flags)
+{
+    const char *s;
+    char *end;
+    int num = 0;
+    unsigned long long int val,endval;
+
+    for (s = arg; s != NULL && *s != 0; s++) {
+        val = strtoull(s, &end, 10);
+        if (end == s && *s != '*') {
+            num++; continue;
+        }
+        if (num >= maxentries) break;
+        if (*end == delim && (flags & PARSE_FLAG_SUFFIX))
+            val *= 1024 * 1024;
+        switch (*end) {
+            case 'g':
+            case 'G':
+                if (flags & PARSE_FLAG_SUFFIX) val *= 1024;
+           	/* fall through */
+            case 'm':
+            case 'M':
+                if (flags & PARSE_FLAG_SUFFIX) val *= 1024;
+           	/* fall through */
+            case 'k':
+            case 'K':
+           	    if (flags & PARSE_FLAG_SUFFIX) val *= 1024;
+           	    break;
+            case '*':
+                val = (unsigned long long int)-1;
+                break;
+            case '-':
+           	    if (!(flags & PARSE_FLAG_BITMASK)) break;
+                s = end + 1;

vl.c +45 -0

+    arg = strdup(opt); token = arg;
+    if (expect_numnodes) {
+        s = strsep(&token, ",");
+        if (s == NULL) {
+            free(arg);
+            return -1;
+        }
+        num = strtol(s, &end, 10);
+        if (s == end) {
+            free(arg);
+            return -1;
+        }
+    }
+    while ((s=strsep(&token, ","))!=NULL) {
+        if ((val = strchr(s, ':'))) {
+            *val++ = 0;
+            if (!strcmp(s, "mem") && mems != NULL) {
+                parse_to_array(val, mems, ';', maxentries, PARSE_FLAG_SUFFIX);
+            } else if (!strcmp(s, "cpu") && cpus != NULL) {
+                parse_to_array(val, cpus, ';', maxentries, PARSE_FLAG_BITMASK);
+            }
+        }
+    }
+    free(arg);
+    return num;
+}
 
 int main(int argc, char **argv, char **envp)
 {

@@ -4556,6 +4653,11 @@ int main(int argc, char **argv, char **e
     for(i = 1; i < MAX_PARALLEL_PORTS; i++)
         parallel_devices[i] = NULL;
     parallel_device_index = 0;
+
+    for(i = 0; i < MAX_NODES; i++) {
+        node_to_cpus[i] = 0;
+        node_mem[i] = 0;
+    }
 
     usb_devices_index = 0;
 

@@ -5011,6 +5113,20 @@ int main(int argc, char **argv, char **e
                     exit(1);
                 }
                 break;
+            case QEMU_OPTION_numa:
+                if (numnumanodes > 0)
+                    parse_numa_args(optarg, node_mem,
+                        node_to_cpus, MAX_NODES, 0);
+                else
+                    numnumanodes = parse_numa_args(optarg,
+                        node_mem, node_to_cpus, MAX_NODES, 1);
+                numnumanodes = parse_numa_args(optarg,
+                    node_mem, node_to_cpus, MAX_NODES, 1);
+                if (numnumanodes < 0) {
+                    fprintf(stderr, "Invalid number of NUMA nodes\n");
+                    exit(1);
+                }
+                break;
 	    case QEMU_OPTION_vnc:
 		vnc_display = optarg;
 		break;

@@ -5151,6 +5267,24 @@ int main(int argc, char **argv, char **e
            monitor_device = "stdio";

vl.c int main(int argc, char **argv, char **e · line 5284

Quoted 4 lines

vl.c +3 -0

+        if (i == numnumanodes) {
+            for (i = 0; i < smp_cpus; i++)
+                node_to_cpus[i % numnumanodes] |= 1<<i;

The way CPUs are allocate here seems strange? Each CPU is assigned round robin? Should you have node 0 contain 1..X, node 1 contain X..Y, node 2 contain Y..smp_cpus?

Quoted 6 lines · Anthony Liguori

vl.c int main(int argc, char **argv, char **e · line 5284

Quoted 4 lines

vl.c +3 -0

+        if (i == numnumanodes) {
+            for (i = 0; i < smp_cpus; i++)
+                node_to_cpus[i % numnumanodes] |= 1<<i;

The way CPUs are allocate here seems strange? Each CPU is assigned round robin? Should you have node 0 contain 1..X, node 1 contain X..Y, node 2 contain Y..smp_cpus?

This is because an algorithm to do it this way is more complicated than this round-robin scheme (imagine distributing 8 CPUs over 3 nodes). Actually I know machines which do this natively (probably for the same reason, code simplicity in the BIOS). OSes can cope with my variant too, there is no guarantee that sequentially numbered CPUs belong to one node. But if you insist, I fix it.

Regards,
Andre.