diff options
| author | Igor Mammedov <imammedo@redhat.com> | 2025-08-14 18:05:53 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2025-08-29 12:48:14 +0200 |
| commit | 73c520b088878682e2d3b7fa19a6366ec8d39829 (patch) | |
| tree | 4766e598cc92df2e3f4c565ff3e451e2f215ea04 /system/physmem.c | |
| parent | 87511341c30d8c9c77178db16491a0ccacc5d64b (diff) | |
| download | focaccia-qemu-73c520b088878682e2d3b7fa19a6366ec8d39829.tar.gz focaccia-qemu-73c520b088878682e2d3b7fa19a6366ec8d39829.zip | |
memory: reintroduce BQL-free fine-grained PIO/MMIO
This patch brings back Jan's idea [1] of BQL-free IO access This will let us make access to ACPI PM/HPET timers cheaper, and prevent BQL contention in case of workload that heavily uses the timers with a lot of vCPUs. 1) 196ea13104f (memory: Add global-locking property to memory regions) ... de7ea885c539 (kvm: Switch to unlocked MMIO) Signed-off-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Link: https://lore.kernel.org/r/20250814160600.2327672-2-imammedo@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'system/physmem.c')
| -rw-r--r-- | system/physmem.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/system/physmem.c b/system/physmem.c index e5dd760e0b..f498572fc8 100644 --- a/system/physmem.c +++ b/system/physmem.c @@ -2900,7 +2900,7 @@ bool prepare_mmio_access(MemoryRegion *mr) { bool release_lock = false; - if (!bql_locked()) { + if (!bql_locked() && !mr->lockless_io) { bql_lock(); release_lock = true; } |