On 6/18/23 23:51, Paolo Bonzini wrote:
RDPID corresponds to a RDMSR(TSC_AUX); however, it is unprivileged
so for user-mode emulation we must provide the value that the kernel
places in the MSR. For Linux, it is a combination of the current CPU
and the current NUMA node, both of which can be retrieved with getcpu(2).
For BSD, just return 0.
RDTSCP is reimplemented as RDTSC + RDPID ECX; the differences in terms
of serializability are not relevant to QEMU.
Signed-off-by: Paolo Bonzini<pbonz...@redhat.com>
---
linux-user/i386/target_cpu.h | 8 ++++++++
linux-user/x86_64/target_cpu.h | 1 +
target/i386/cpu.c | 10 +++++++++-
target/i386/helper.h | 2 +-
target/i386/tcg/misc_helper.c | 21 +++++++++++++++------
target/i386/tcg/translate.c | 15 +++++++++++++--
6 files changed, 47 insertions(+), 10 deletions(-)
diff --git a/linux-user/i386/target_cpu.h b/linux-user/i386/target_cpu.h
index 52caf788cc3..3539f790222 100644
--- a/linux-user/i386/target_cpu.h
+++ b/linux-user/i386/target_cpu.h
@@ -54,4 +54,12 @@ static inline abi_ulong get_sp_from_cpustate(CPUX86State
*state)
{
return state->regs[R_ESP];
}
+
+static inline uint32_t get_cpunode(void)
+{
+ unsigned cpu, node;
+ getcpu(&cpu, &node);
+ return (node << 12) | (cpu & 0xfff);
+}
+
What is our minimum glibc version? This requires 2.29.
Also, not especially fond of the placement. target/ including linux-user/ header isn't
nice. Might as well just place these 3 lines in misc_helper.c to begin.
r~
