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| author | David Matlack <dmatlack@google.com> | 2024-06-11 15:05:12 -0700 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-06-14 09:25:03 -0700 |
| commit | 0089c055b56024edf90e85dc852440b713ce8cb5 (patch) | |
| tree | 66d5727ce88f449453f308f7db58d3ab5f4ce9e1 /arch/x86 | |
| parent | 3d4a5a45ca26f8de9e0a4f384a2fb0967b8566b5 (diff) | |
| download | linux-stable-0089c055b56024edf90e85dc852440b713ce8cb5.tar.gz linux-stable-0089c055b56024edf90e85dc852440b713ce8cb5.tar.bz2 linux-stable-0089c055b56024edf90e85dc852440b713ce8cb5.zip | |
KVM: x86/mmu: Avoid reacquiring RCU if TDP MMU fails to allocate an SP
Avoid needlessly reacquiring the RCU read lock if the TDP MMU fails to
allocate a shadow page during eager page splitting. Opportunistically
drop the local variable ret as well now that it's no longer necessary.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20240611220512.2426439-5-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 028f5a667482..c512a02c44a1 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1402,7 +1402,6 @@ static int tdp_mmu_split_huge_pages_root(struct kvm *kvm, { struct kvm_mmu_page *sp = NULL; struct tdp_iter iter; - int ret = 0; rcu_read_lock(); @@ -1440,16 +1439,15 @@ retry: else write_lock(&kvm->mmu_lock); - rcu_read_lock(); - if (!sp) { - ret = -ENOMEM; trace_kvm_mmu_split_huge_page(iter.gfn, iter.old_spte, - iter.level, ret); - break; + iter.level, -ENOMEM); + return -ENOMEM; } + rcu_read_lock(); + iter.yielded = true; continue; } @@ -1472,7 +1470,7 @@ retry: if (sp) tdp_mmu_free_sp(sp); - return ret; + return 0; } |