qemu/accel
Marcelo Tosatti 3b6f485275 kvm: reuse per-vcpu stats fd to avoid vcpu interruption
A regression has been detected in latency testing of KVM guests.
More specifically, it was observed that the cyclictest
numbers inside of an isolated vcpu (running on isolated pcpu) are:

Where a maximum of 50us is acceptable.

The implementation of KVM_GET_STATS_FD uses run_on_cpu to query
per vcpu statistics, which interrupts the vcpu (and is unnecessary).

To fix this, open the per vcpu stats fd on vcpu initialization,
and read from that fd from QEMU's main thread.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-06-26 10:23:01 +02:00
..
hvf accel/hvf: Report HV_DENIED error 2023-06-13 11:28:58 +02:00
kvm kvm: reuse per-vcpu stats fd to avoid vcpu interruption 2023-06-26 10:23:01 +02:00
qtest meson: Replace CONFIG_SOFTMMU -> CONFIG_SYSTEM_ONLY 2023-06-20 10:01:30 +02:00
stubs meson: Replace CONFIG_SOFTMMU -> CONFIG_SYSTEM_ONLY 2023-06-20 10:01:30 +02:00
tcg accel/tcg/cpu-exec: Use generic 'helper-proto-common.h' header 2023-06-20 10:01:30 +02:00
xen accel/xen: Fix DM state change notification in dm_restrict mode 2023-03-23 09:56:54 +00:00
accel-blocker.c accel: introduce accelerator blocker API 2023-01-11 09:59:39 +01:00
accel-common.c gdbstub: move sstep flags probing into AccelClass 2022-10-06 11:53:41 +01:00
accel-softmmu.c *: Add missing includes of qemu/error-report.h 2023-03-22 15:06:57 +00:00
accel-softmmu.h accel: replace struct CpusAccel with AccelOpsClass 2021-02-05 10:24:15 -10:00
accel-user.c accel: extend AccelState and AccelClass to user-mode 2021-02-05 10:24:15 -10:00
dummy-cpus.c accel/qtest: Support qtest accelerator for Windows 2022-10-28 11:17:12 +02:00
Kconfig Add NVMM accelerator: configure and build logic 2021-05-04 14:15:34 +02:00
meson.build meson: Replace softmmu_ss -> system_ss 2023-06-20 10:01:30 +02:00