Re: [PATCH v12 11/84] KVM: Rename gfn_to_page_many_atomic() to kvm_prefetch_pages()
From: Alex Bennée <hidden>
Date: 2024-08-02 11:16:15
Also in:
kvm, kvm-riscv, kvmarm, linux-arm-kernel, linux-mips, linux-riscv, lkml, loongarch
Sean Christopherson [off-list ref] writes:
Rename gfn_to_page_many_atomic() to kvm_prefetch_pages() to try and communicate its true purpose, as the "atomic" aspect is essentially a side effect of the fact that x86 uses the API while holding mmu_lock.
It's never too late to start adding some kdoc annotations to a function and renaming a kvm_host API call seems like a good time to do it.
E.g. even if mmu_lock weren't held, KVM wouldn't want to fault-in pages, as the goal is to opportunistically grab surrounding pages that have already been accessed and/or dirtied by the host, and to do so quickly. Signed-off-by: Sean Christopherson <seanjc@google.com> ---
<snip> /** * kvm_prefetch_pages() - opportunistically grab previously accessed pages * @slot: which @kvm_memory_slot the pages are in * @gfn: guest frame * @pages: array to receives page pointers * @nr_pages: number of pages * * Returns the number of pages actually mapped. */ ?
quoted hunk
-int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn, - struct page **pages, int nr_pages) +int kvm_prefetch_pages(struct kvm_memory_slot *slot, gfn_t gfn, + struct page **pages, int nr_pages) { unsigned long addr; gfn_t entry = 0;@@ -3075,7 +3075,7 @@ int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn, return get_user_pages_fast_only(addr, nr_pages, FOLL_WRITE, pages); } -EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic); +EXPORT_SYMBOL_GPL(kvm_prefetch_pages); /* * Do not use this helper unless you are absolutely certain the gfn _must_ be
-- Alex Bennée Virtualisation Tech Lead @ Linaro