[libvirt] [PATCH v3] Implement CPU topology support for QEMU driver
Jiri Denemark
jdenemar at redhat.com
Mon Jan 18 15:51:52 UTC 2010
QEMU's command line equivalent for the following domain XML fragment
<vcpus>2</vcpus>
<cpu ...>
...
<topology sockets='1' cores='2', threads='1'/>
</cpu>
is
-smp 2,sockets=1,cores=2,threads=1
This syntax was introduced in QEMU-0.12.
Version 2 changes:
- -smp argument build split into a separate function
- always add ",sockets=S,cores=C,threads=T" to -smp if qemu supports it
- use qemuParseCommandLineKeywords for command line parsing
Version 3 changes:
- ADD_ARG_LIT => ADD_ARG and line reordering in qemudBuildCommandLine
- rebased
Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
---
src/qemu/qemu_conf.c | 157 ++++++++++++++++++++++++++++++++++++++++++++-----
src/qemu/qemu_conf.h | 3 +-
2 files changed, 143 insertions(+), 17 deletions(-)
diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
index 024b2ba..1fbb86a 100644
--- a/src/qemu/qemu_conf.c
+++ b/src/qemu/qemu_conf.c
@@ -1,7 +1,7 @@
/*
* qemu_conf.c: QEMU configuration management
*
- * Copyright (C) 2006, 2007, 2008, 2009 Red Hat, Inc.
+ * Copyright (C) 2006, 2007, 2008, 2009, 2010 Red Hat, Inc.
* Copyright (C) 2006 Daniel P. Berrange
*
* This library is free software; you can redistribute it and/or
@@ -1119,6 +1119,10 @@ static unsigned int qemudComputeCmdFlags(const char *help,
flags |= QEMUD_CMD_FLAG_DEVICE;
if (strstr(help, "-sdl"))
flags |= QEMUD_CMD_FLAG_SDL;
+ if (strstr(help, "cores=") &&
+ strstr(help, "threads=") &&
+ strstr(help, "sockets="))
+ flags |= QEMUD_CMD_FLAG_SMP_TOPOLOGY;
if (version >= 9000)
flags |= QEMUD_CMD_FLAG_VNC_COLON;
@@ -2676,6 +2680,39 @@ no_memory:
goto cleanup;
}
+static char *
+qemudBuildCommandLineSmp(virConnectPtr conn,
+ const virDomainDefPtr def,
+ int qemuCmdFlags)
+{
+ virBuffer buf = VIR_BUFFER_INITIALIZER;
+
+ virBufferVSprintf(&buf, "%lu", def->vcpus);
+
+ if ((qemuCmdFlags & QEMUD_CMD_FLAG_SMP_TOPOLOGY)) {
+ /* sockets, cores, and threads are either all zero
+ * or all non-zero, thus checking one of them is enough */
+ if (def->cpu && def->cpu->sockets) {
+ virBufferVSprintf(&buf, ",sockets=%u", def->cpu->sockets);
+ virBufferVSprintf(&buf, ",cores=%u", def->cpu->cores);
+ virBufferVSprintf(&buf, ",threads=%u", def->cpu->threads);
+ }
+ else {
+ virBufferVSprintf(&buf, ",sockets=%lu", def->vcpus);
+ virBufferVSprintf(&buf, ",cores=%u", 1);
+ virBufferVSprintf(&buf, ",threads=%u", 1);
+ }
+ }
+
+ if (virBufferError(&buf)) {
+ virBufferFreeAndReset(&buf);
+ virReportOOMError(conn);
+ return NULL;
+ }
+
+ return virBufferContentAndReset(&buf);
+}
+
/*
* Constructs a argv suitable for launching qemu with config defined
@@ -2694,7 +2731,6 @@ int qemudBuildCommandLine(virConnectPtr conn,
const char *migrateFrom) {
int i;
char memory[50];
- char vcpus[50];
char boot[VIR_DOMAIN_BOOT_LAST];
struct utsname ut;
int disableKQEMU = 0;
@@ -2708,6 +2744,7 @@ int qemudBuildCommandLine(virConnectPtr conn,
char uuid[VIR_UUID_STRING_BUFLEN];
char domid[50];
char *cpu;
+ char *smp;
uname_normalize(&ut);
@@ -2850,7 +2887,6 @@ int qemudBuildCommandLine(virConnectPtr conn,
* is not supported, then they're out of luck anyway
*/
snprintf(memory, sizeof(memory), "%lu", def->maxmem/1024);
- snprintf(vcpus, sizeof(vcpus), "%lu", def->vcpus);
snprintf(domid, sizeof(domid), "%d", def->id);
ADD_ENV_LIT("LC_ALL=C");
@@ -2913,8 +2949,11 @@ int qemudBuildCommandLine(virConnectPtr conn,
ADD_ARG_LIT("-mem-path");
ADD_ARG_LIT(driver->hugepage_path);
}
+
ADD_ARG_LIT("-smp");
- ADD_ARG_LIT(vcpus);
+ if (!(smp = qemudBuildCommandLineSmp(conn, def, qemuCmdFlags)))
+ goto error;
+ ADD_ARG(smp);
if (qemuCmdFlags & QEMUD_CMD_FLAG_NAME) {
ADD_ARG_LIT("-name");
@@ -4647,6 +4686,27 @@ error:
}
+static virCPUDefPtr
+qemuInitGuestCPU(virConnectPtr conn,
+ virDomainDefPtr dom)
+{
+ if (!dom->cpu) {
+ virCPUDefPtr cpu;
+
+ if (VIR_ALLOC(cpu) < 0) {
+ virReportOOMError(conn);
+ return NULL;
+ }
+
+ cpu->type = VIR_CPU_TYPE_GUEST;
+ cpu->match = VIR_CPU_MATCH_EXACT;
+ dom->cpu = cpu;
+ }
+
+ return dom->cpu;
+}
+
+
static int
qemuParseCommandLineCPU(virConnectPtr conn,
virDomainDefPtr dom,
@@ -4656,10 +4716,8 @@ qemuParseCommandLineCPU(virConnectPtr conn,
const char *p = val;
const char *next;
- if (VIR_ALLOC(cpu) < 0)
- goto no_memory;
-
- cpu->type = VIR_CPU_TYPE_GUEST;
+ if (!(cpu = qemuInitGuestCPU(conn, dom)))
+ goto error;
do {
if (*p == '\0' || *p == ',')
@@ -4703,7 +4761,6 @@ qemuParseCommandLineCPU(virConnectPtr conn,
}
} while ((p = next));
- dom->cpu = cpu;
return 0;
syntax:
@@ -4714,11 +4771,84 @@ syntax:
no_memory:
virReportOOMError(conn);
error:
- virCPUDefFree(cpu);
return -1;
}
+static int
+qemuParseCommandLineSmp(virConnectPtr conn,
+ virDomainDefPtr dom,
+ const char *val)
+{
+ unsigned int sockets = 0;
+ unsigned int cores = 0;
+ unsigned int threads = 0;
+ int i;
+ int nkws;
+ char **kws;
+ char **vals;
+ int n;
+ char *end;
+ int ret;
+
+ nkws = qemuParseCommandLineKeywords(conn, val, &kws, &vals, 1);
+ if (nkws < 0)
+ return -1;
+
+ for (i = 0; i < nkws; i++) {
+ if (vals[i] == NULL) {
+ if (i > 0 ||
+ virStrToLong_i(kws[i], &end, 10, &n) < 0 ||
+ !end || *end != '\0')
+ goto syntax;
+ dom->vcpus = n;
+ } else {
+ if (virStrToLong_i(vals[i], &end, 10, &n) < 0 ||
+ !end || *end != '\0')
+ goto syntax;
+ if (STREQ(kws[i], "sockets"))
+ sockets = n;
+ else if (STREQ(kws[i], "cores"))
+ cores = n;
+ else if (STREQ(kws[i], "threads"))
+ threads = n;
+ else
+ goto syntax;
+ }
+ }
+
+ if (sockets && cores && threads) {
+ virCPUDefPtr cpu;
+
+ if (!(cpu = qemuInitGuestCPU(conn, dom)))
+ goto error;
+ cpu->sockets = sockets;
+ cpu->cores = cores;
+ cpu->threads = threads;
+ } else if (sockets || cores || threads)
+ goto syntax;
+
+ ret = 0;
+
+cleanup:
+ for (i = 0; i < nkws; i++) {
+ VIR_FREE(kws[i]);
+ VIR_FREE(vals[i]);
+ }
+ VIR_FREE(kws);
+ VIR_FREE(vals);
+
+ return ret;
+
+syntax:
+ qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
+ _("cannot parse CPU topology '%s'"), val);
+error:
+ ret = -1;
+ goto cleanup;
+}
+
+
/*
* Analyse the env and argv settings and reconstruct a
* virDomainDefPtr representing these settings as closely
@@ -4867,14 +4997,9 @@ virDomainDefPtr qemuParseCommandLine(virConnectPtr conn,
}
def->memory = def->maxmem = mem * 1024;
} else if (STREQ(arg, "-smp")) {
- int vcpus;
WANT_VALUE();
- if (virStrToLong_i(val, NULL, 10, &vcpus) < 0) {
- qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR, \
- _("cannot parse CPU count '%s'"), val);
+ if (qemuParseCommandLineSmp(conn, def, val) < 0)
goto error;
- }
- def->vcpus = vcpus;
} else if (STREQ(arg, "-uuid")) {
WANT_VALUE();
if (virUUIDParse(val, def->uuid) < 0) {
diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h
index ed2d32b..c6f8c30 100644
--- a/src/qemu/qemu_conf.h
+++ b/src/qemu/qemu_conf.h
@@ -1,7 +1,7 @@
/*
* qemu_conf.h: QEMU configuration management
*
- * Copyright (C) 2006, 2007, 2009 Red Hat, Inc.
+ * Copyright (C) 2006, 2007, 2009, 2010 Red Hat, Inc.
* Copyright (C) 2006 Daniel P. Berrange
*
* This library is free software; you can redistribute it and/or
@@ -80,6 +80,7 @@ enum qemud_cmd_flags {
QEMUD_CMD_FLAG_BALLOON = (1 << 25), /* -balloon available */
QEMUD_CMD_FLAG_DEVICE = (1 << 26), /* Is the new -device arg available */
QEMUD_CMD_FLAG_SDL = (1 << 27), /* Is the new -sdl arg available */
+ QEMUD_CMD_FLAG_SMP_TOPOLOGY = (1 << 28), /* Is sockets=s,cores=c,threads=t available for -smp? */
};
/* Main driver state */
--
1.6.6
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