On Tue, May 30, 2023 at 08:20:34PM +0800, Tianrui Zhao wrote: > Date: Tue, 30 May 2023 20:20:34 +0800 > From: Tianrui Zhao <[email protected]> > Subject: [PATCH] hw/smbios: fix thead count field in type 4 table > X-Mailer: git-send-email 2.39.1 > > The thread_count value in smbios type_4 table should be > (ms->smp.cores * ms->smp.threads). As according to smbios spec 7.5 > Processor Information (Type 4), the field "Thread Count" means the > "Number of threads per processor socket" rather than number of > threads per core. > > When apply this patch, use "-smp 4,sockets=1,cores=2,threads=2" to > boot VM, the dmidecode -t 4 shows like: > > Handle 0x0400, DMI type 4, 48 bytes > Processor Information > Socket Designation: CPU 0 > ... > Core Count: 2 > Core Enabled: 2 > Thread Count: 4 > Characteristics: None > > Signed-off-by: Tianrui Zhao <[email protected]> > --- > hw/smbios/smbios.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/hw/smbios/smbios.c b/hw/smbios/smbios.c > index d2007e70fb..56aeaa069d 100644 > --- a/hw/smbios/smbios.c > +++ b/hw/smbios/smbios.c > @@ -713,6 +713,7 @@ static void smbios_build_type_4_table(MachineState *ms, > unsigned instance) > { > char sock_str[128]; > size_t tbl_len = SMBIOS_TYPE_4_LEN_V28; > + int count; > > if (smbios_ep_type == SMBIOS_ENTRY_POINT_TYPE_64) { > tbl_len = SMBIOS_TYPE_4_LEN_V30; > @@ -749,15 +750,15 @@ static void smbios_build_type_4_table(MachineState *ms, > unsigned instance) > > t->core_count = (ms->smp.cores > 255) ? 0xFF : ms->smp.cores; > t->core_enabled = t->core_count; > - > - t->thread_count = (ms->smp.threads > 255) ? 0xFF : ms->smp.threads; > + count = ms->smp.cores * ms->smp.threads;
Hi Ani & Tianrui, >From the comment of CpuTopology (include/hw/boards.h): ms->cores means the "the number of cores in one cluster". ms->threads means the "the number of threads in one core". So ms->cores * ms->threads means the number of threads in one cluster not one socket. That's why I count the number of threads in a socket by "ms->smp.max_cpus / ms->smp.sockets" in [1]. The other correct way is: ms->smp.cluster * ms->smp.cores * ms->smp.threads. [1]: https://lists.gnu.org/archive/html/qemu-devel/2023-05/msg07229.html Thanks, Zhao > + t->thread_count = (count > 255) ? 0xFF : count; > > t->processor_characteristics = cpu_to_le16(0x02); /* Unknown */ > t->processor_family2 = cpu_to_le16(0x01); /* Other */ > > if (tbl_len == SMBIOS_TYPE_4_LEN_V30) { > t->core_count2 = t->core_enabled2 = cpu_to_le16(ms->smp.cores); > - t->thread_count2 = cpu_to_le16(ms->smp.threads); > + t->thread_count2 = cpu_to_le16(count); > } > > SMBIOS_BUILD_TABLE_POST; > -- > 2.39.1 > >
