From 22419c2a90b859dcab49f9472259ad8a3ce091d6 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Tue, 8 Sep 2015 11:21:31 +1000 Subject: [PATCH] pseries: Fix incorrect calculation of threads per socket for chip-id The device tree presented to pseries machine type guests includes an ibm,chip-id property which gives essentially the socket number of each vcpu core (individual vcpu threads don't get a node in the device tree). To calculate this, it uses a vcpus_per_socket variable computed as (smp_cpus / #sockets). This is correct for the usual case where smp_cpus == smp_threads * smp_cores * #sockets. However, you can start QEMU with the number of cores and threads mismatching the total number of vcpus (whether that _should_ be permitted is a topic for another day). It's a bit hard to say what the "real" number of vcpus per socket here is, but for most purposes (smp_threads * smp_cores) will more meaningfully match how QEMU behaves with respect to socket boundaries. Signed-off-by: David Gibson Reviewed-by: Alexey Kardashevskiy --- hw/ppc/spapr.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index a69d7e4754..ac0d2fe892 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -630,9 +630,7 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset, uint32_t cpufreq = kvm_enabled() ? kvmppc_get_clockfreq() : 1000000000; uint32_t page_sizes_prop[64]; size_t page_sizes_prop_size; - QemuOpts *opts = qemu_opts_find(qemu_find_opts("smp-opts"), NULL); - unsigned sockets = opts ? qemu_opt_get_number(opts, "sockets", 0) : 0; - uint32_t cpus_per_socket = sockets ? (smp_cpus / sockets) : 1; + uint32_t vcpus_per_socket = smp_threads * smp_cores; uint32_t pft_size_prop[] = {0, cpu_to_be32(spapr->htab_shift)}; _FDT((fdt_setprop_cell(fdt, offset, "reg", index))); @@ -701,7 +699,7 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset, } _FDT((fdt_setprop_cell(fdt, offset, "ibm,chip-id", - cs->cpu_index / cpus_per_socket))); + cs->cpu_index / vcpus_per_socket))); _FDT((fdt_setprop(fdt, offset, "ibm,pft-size", pft_size_prop, sizeof(pft_size_prop))));