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charset="us-ascii" X-Rspamd-Queue-Id: B511414001A X-Stat-Signature: y9hear8y8syhecmrwgmac8e5zjft5utu X-Rspamd-Server: rspam09 X-Rspam-User: X-HE-Tag: 1723856453-886562 X-HE-Meta: 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 Yqa5OhK9 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Jul 25, 2024, David Matlack wrote: > On 2024-07-24 01:10 AM, James Houghton wrote: > > Optimize both kvm_age_gfn and kvm_test_age_gfn's interaction with the > > nit: Use () when referring to functions. > > > shadow MMU by, rather than checking if our memslot has rmaps, check if > > there are any indirect_shadow_pages at all. > > What is optimized by checking indirect_shadow_pages instead of > have_rmaps and what's the benefit? Smells like a premature optimization. Checking indirect_shadow_pages avoids taking mmu_lock for write when KVM doesn't currently have shadow MMU pages, but did at some point in the past, whereas kvm_memslots_have_rmaps() is sticky and will return true forever. > > Also, for kvm_test_age_gfn, reorder the TDP MMU check to be first. If we > > find that the range is young, we do not need to check the shadow MMU. > > This should be a separate commit since it's a logically distinct change > and no dependency on the other change in this commit (other than both > touch the same function). > > Splitting the commits up will also make it easier to write more specific > short logs (instead of "optimize a little bit" :) +1. Especially code movement and refactoring, e.g. factoring out tdp_mmu_clear_spte_bits_atomic() would ideally be in a standalone patch that's dead simple to review.