From e6816458624813de4a31f89096a620b410e1c2b8 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Fri, 14 Oct 2022 15:47:19 +0200 Subject: hostmem: Allow for specifying a ThreadContext for preallocation Let's allow for specifying a thread context via the "prealloc-context" property. When set, preallcoation threads will be crated via the thread context -- inheriting the same CPU affinity as the thread context. Pinning preallcoation threads to CPUs can heavily increase performance in NUMA setups, because, preallocation from a CPU close to the target NUMA node(s) is faster then preallocation from a CPU further remote, simply because of memory bandwidth for initializing memory with zeroes. This is especially relevant for very large VMs backed by huge/gigantic pages, whereby preallocation is mandatory. Reviewed-by: Michal Privoznik Message-Id: <20221014134720.168738-7-david@redhat.com> Signed-off-by: David Hildenbrand --- include/sysemu/hostmem.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/sysemu/hostmem.h b/include/sysemu/hostmem.h index 9ff5c16963..39326f1d4f 100644 --- a/include/sysemu/hostmem.h +++ b/include/sysemu/hostmem.h @@ -18,6 +18,7 @@ #include "qom/object.h" #include "exec/memory.h" #include "qemu/bitmap.h" +#include "qemu/thread-context.h" #define TYPE_MEMORY_BACKEND "memory-backend" OBJECT_DECLARE_TYPE(HostMemoryBackend, HostMemoryBackendClass, @@ -66,6 +67,7 @@ struct HostMemoryBackend { bool merge, dump, use_canonical_path; bool prealloc, is_mapped, share, reserve; uint32_t prealloc_threads; + ThreadContext *prealloc_context; DECLARE_BITMAP(host_nodes, MAX_NODES + 1); HostMemPolicy policy; -- cgit v1.2.3-55-g7522