From 98e56ae6798cc5f5e432e8d93d5d18ebdeb7e496 Mon Sep 17 00:00:00 2001 From: Thomas Huth Date: Fri, 5 Oct 2018 16:13:12 +0200 Subject: accel: Improve selection of the default accelerator When compiling with "--disable-tcg", we currently still use "tcg" as default accelerator. "kvm" should be used in this case instead. Also, some downstream distros provide QEMU binaries which have "kvm" in their names (e.g. "qemu-kvm" on RHEL or "kvm" on Ubuntu) that use KVM by default - and some users might want to do something similar with upstream binaries, too. Accomodate them by using "kvm:tcg" as default when we detect such a binary name. Signed-off-by: Thomas Huth Message-Id: <1538748792-19444-1-git-send-email-thuth@redhat.com> Signed-off-by: Paolo Bonzini --- accel/accel.c | 18 +++++++++++++++--- include/sysemu/accel.h | 2 +- vl.c | 2 +- 3 files changed, 17 insertions(+), 5 deletions(-) diff --git a/accel/accel.c b/accel/accel.c index 6db5d8f4df..68b6d56323 100644 --- a/accel/accel.c +++ b/accel/accel.c @@ -69,7 +69,7 @@ static int accel_init_machine(AccelClass *acc, MachineState *ms) return ret; } -void configure_accelerator(MachineState *ms) +void configure_accelerator(MachineState *ms, const char *progname) { const char *accel; char **accel_list, **tmp; @@ -80,8 +80,20 @@ void configure_accelerator(MachineState *ms) accel = qemu_opt_get(qemu_get_machine_opts(), "accel"); if (accel == NULL) { - /* Use the default "accelerator", tcg */ - accel = "tcg"; + /* Select the default accelerator */ + int pnlen = strlen(progname); + if (pnlen >= 3 && g_str_equal(&progname[pnlen - 3], "kvm")) { + /* If the program name ends with "kvm", we prefer KVM */ + accel = "kvm:tcg"; + } else { +#if defined(CONFIG_TCG) + accel = "tcg"; +#elif defined(CONFIG_KVM) + accel = "kvm"; +#else +#error "No default accelerator available" +#endif + } } accel_list = g_strsplit(accel, ":", 0); diff --git a/include/sysemu/accel.h b/include/sysemu/accel.h index f331d128e9..5565e00a96 100644 --- a/include/sysemu/accel.h +++ b/include/sysemu/accel.h @@ -66,7 +66,7 @@ typedef struct AccelClass { extern unsigned long tcg_tb_size; -void configure_accelerator(MachineState *ms); +void configure_accelerator(MachineState *ms, const char *progname); /* Called just before os_setup_post (ie just before drop OS privs) */ void accel_setup_post(MachineState *ms); diff --git a/vl.c b/vl.c index 064872cc98..a903619d14 100644 --- a/vl.c +++ b/vl.c @@ -4329,7 +4329,7 @@ int main(int argc, char **argv, char **envp) qemu_opt_foreach(machine_opts, machine_set_property, current_machine, &error_fatal); - configure_accelerator(current_machine); + configure_accelerator(current_machine, argv[0]); if (!qtest_enabled() && machine_class->deprecation_reason) { error_report("Machine type '%s' is deprecated: %s", -- cgit v1.2.3