From: Anthony PERARD <anthony.per...@citrix.com> This option gives the ability to switch one "accelerator" like kvm, xen or the default one tcg. We can specify more than one accelerator by separate them by a comma. QEMU will try each one and use the first whose works.
So, -accel xen,kvm,tcg which would try Xen support first, then KVM and finaly tcg if none of the other works. Signed-off-by: Anthony PERARD <anthony.per...@citrix.com> --- arch_init.c | 5 +++ arch_init.h | 1 + qemu-options.hx | 10 ++++++ vl.c | 85 +++++++++++++++++++++++++++++++++++++++++++++++------- 4 files changed, 90 insertions(+), 11 deletions(-) diff --git a/arch_init.c b/arch_init.c index 4486925..e0d7a4c 100644 --- a/arch_init.c +++ b/arch_init.c @@ -639,6 +639,11 @@ int audio_available(void) #endif } +int tcg_available(void) +{ + return 1; +} + int kvm_available(void) { #ifdef CONFIG_KVM diff --git a/arch_init.h b/arch_init.h index 682890c..f0fb6a0 100644 --- a/arch_init.h +++ b/arch_init.h @@ -27,6 +27,7 @@ void do_acpitable_option(const char *optarg); void do_smbios_option(const char *optarg); void cpudef_init(void); int audio_available(void); +int tcg_available(void); int kvm_available(void); int xen_available(void); diff --git a/qemu-options.hx b/qemu-options.hx index 4d99a58..958d126 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -1975,6 +1975,16 @@ Enable KVM full virtualization support. This option is only available if KVM support is enabled when compiling. ETEXI +DEF("accel", HAS_ARG, QEMU_OPTION_accel, \ + "-accel accel use an accelerator (kvm,xen,tcg), default is tcg\n", QEMU_ARCH_ALL) +STEXI +...@item -accel @var{accel}[,@var{accel}[,...]] +...@findex -accel +This is use to enable an accelerator, in kvm,xen,tcg. +By default, it use only tcg. If there a more than one accelerator +specified, the next one is used if the first don't work. +ETEXI + DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) DEF("xen-create", 0, QEMU_OPTION_xen_create, diff --git a/vl.c b/vl.c index c58583d..2917e32 100644 --- a/vl.c +++ b/vl.c @@ -242,6 +242,7 @@ static void *boot_set_opaque; static NotifierList exit_notifiers = NOTIFIER_LIST_INITIALIZER(exit_notifiers); +static int tcg_allowed = 1; int kvm_allowed = 0; uint32_t xen_domid; enum xen_mode xen_mode = XEN_EMULATE; @@ -1723,6 +1724,72 @@ static int debugcon_parse(const char *devname) return 0; } +static int tcg_init(int smp_cpus) +{ + return 0; +} + +static struct { + const char *opt_name; + const char *name; + int (*available)(void); + int (*init)(int smp_cpus); + int *allowed; +} accel_list[] = { + { "tcg", "tcg", tcg_available, tcg_init, &tcg_allowed }, + { "kvm", "KVM", kvm_available, kvm_init, &kvm_allowed }, +}; + +static int accel_parse_init(const char *opts) +{ + const char *p = opts; + char buf[10]; + int i, ret; + bool accel_initalised = 0; + bool init_failed = 0; + + while (!accel_initalised && *p != '\0') { + if (*p == ',') { + p++; + } + p = get_opt_name(buf, sizeof (buf), p, ','); + for (i = 0; i < ARRAY_SIZE(accel_list); i++) { + if (strcmp(accel_list[i].opt_name, buf) == 0) { + ret = accel_list[i].init(smp_cpus); + if (ret < 0) { + init_failed = 1; + if (!accel_list[i].available()) { + printf("%s not supported for this target\n", + accel_list[i].name); + } else { + fprintf(stderr, "failed to initialize %s: %s\n", + accel_list[i].name, + strerror(-ret)); + } + } else { + accel_initalised = 1; + *(accel_list[i].allowed) = 1; + } + break; + } + } + if (i == ARRAY_SIZE(accel_list)) { + fprintf(stderr, "\"%s\" accelerator does not exist.\n", buf); + } + } + + if (!accel_initalised) { + fprintf(stderr, "No accelerator found!\n"); + exit(1); + } + + if (init_failed) { + fprintf(stderr, "Back to %s accelerator.\n", accel_list[i].name); + } + + return !accel_initalised; +} + void qemu_add_exit_notifier(Notifier *notify) { notifier_list_add(&exit_notifiers, notify); @@ -1802,6 +1869,7 @@ int main(int argc, char **argv, char **envp) const char *incoming = NULL; int show_vnc_port = 0; int defconfig = 1; + const char *accel_list_opts = "tcg"; #ifdef CONFIG_SIMPLE_TRACE const char *trace_file = NULL; @@ -2409,7 +2477,10 @@ int main(int argc, char **argv, char **envp) do_smbios_option(optarg); break; case QEMU_OPTION_enable_kvm: - kvm_allowed = 1; + accel_list_opts = "kvm"; + break; + case QEMU_OPTION_accel: + accel_list_opts = optarg; break; case QEMU_OPTION_usb: usb_enabled = 1; @@ -2719,16 +2790,8 @@ int main(int argc, char **argv, char **envp) exit(1); } - if (kvm_allowed) { - int ret = kvm_init(smp_cpus); - if (ret < 0) { - if (!kvm_available()) { - printf("KVM not supported for this target\n"); - } else { - fprintf(stderr, "failed to initialize KVM: %s\n", strerror(-ret)); - } - exit(1); - } + if (accel_list_opts) { + accel_parse_init(accel_list_opts); } if (qemu_init_main_loop()) { -- 1.7.1