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Howlett" , Mike Rapoport , Michal Hocko , Shakeel Butt , Jann Horn , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, Peter Zijlstra , Ingo Molnar , Will Deacon , Boqun Feng , Waiman Long , Sebastian Andrzej Siewior , Clark Williams , Steven Rostedt References: <6f45d01a-7586-4d8a-8339-fdfbda4c971e@suse.cz> From: Vlastimil Babka Autocrypt: addr=vbabka@suse.cz; keydata= xsFNBFZdmxYBEADsw/SiUSjB0dM+vSh95UkgcHjzEVBlby/Fg+g42O7LAEkCYXi/vvq31JTB KxRWDHX0R2tgpFDXHnzZcQywawu8eSq0LxzxFNYMvtB7sV1pxYwej2qx9B75qW2plBs+7+YB 87tMFA+u+L4Z5xAzIimfLD5EKC56kJ1CsXlM8S/LHcmdD9Ctkn3trYDNnat0eoAcfPIP2OZ+ 9oe9IF/R28zmh0ifLXyJQQz5ofdj4bPf8ecEW0rhcqHfTD8k4yK0xxt3xW+6Exqp9n9bydiy tcSAw/TahjW6yrA+6JhSBv1v2tIm+itQc073zjSX8OFL51qQVzRFr7H2UQG33lw2QrvHRXqD Ot7ViKam7v0Ho9wEWiQOOZlHItOOXFphWb2yq3nzrKe45oWoSgkxKb97MVsQ+q2SYjJRBBH4 8qKhphADYxkIP6yut/eaj9ImvRUZZRi0DTc8xfnvHGTjKbJzC2xpFcY0DQbZzuwsIZ8OPJCc LM4S7mT25NE5kUTG/TKQCk922vRdGVMoLA7dIQrgXnRXtyT61sg8PG4wcfOnuWf8577aXP1x 6mzw3/jh3F+oSBHb/GcLC7mvWreJifUL2gEdssGfXhGWBo6zLS3qhgtwjay0Jl+kza1lo+Cv BB2T79D4WGdDuVa4eOrQ02TxqGN7G0Biz5ZLRSFzQSQwLn8fbwARAQABzSBWbGFzdGltaWwg QmFia2EgPHZiYWJrYUBzdXNlLmN6PsLBlAQTAQoAPgIbAwULCQgHAwUVCgkICwUWAgMBAAIe AQIXgBYhBKlA1DSZLC6OmRA9UCJPp+fMgqZkBQJnyBr8BQka0IFQAAoJECJPp+fMgqZkqmMQ AIbGN95ptUMUvo6aAdhxaOCHXp1DfIBuIOK/zpx8ylY4pOwu3GRe4dQ8u4XS9gaZ96Gj4bC+ jwWcSmn+TjtKW3rH1dRKopvC07tSJIGGVyw7ieV/5cbFffA8NL0ILowzVg8w1ipnz1VTkWDr 2zcfslxJsJ6vhXw5/npcY0ldeC1E8f6UUoa4eyoskd70vO0wOAoGd02ZkJoox3F5ODM0kjHu Y97VLOa3GG66lh+ZEelVZEujHfKceCw9G3PMvEzyLFbXvSOigZQMdKzQ8D/OChwqig8wFBmV QCPS4yDdmZP3oeDHRjJ9jvMUKoYODiNKsl2F+xXwyRM2qoKRqFlhCn4usVd1+wmv9iLV8nPs 2Db1ZIa49fJet3Sk3PN4bV1rAPuWvtbuTBN39Q/6MgkLTYHb84HyFKw14Rqe5YorrBLbF3rl M51Dpf6Egu1yTJDHCTEwePWug4XI11FT8lK0LNnHNpbhTCYRjX73iWOnFraJNcURld1jL1nV r/LRD+/e2gNtSTPK0Qkon6HcOBZnxRoqtazTU6YQRmGlT0v+rukj/cn5sToYibWLn+RoV1CE Qj6tApOiHBkpEsCzHGu+iDQ1WT0Idtdynst738f/uCeCMkdRu4WMZjteQaqvARFwCy3P/jpK uvzMtves5HvZw33ZwOtMCgbpce00DaET4y/UzsBNBFsZNTUBCACfQfpSsWJZyi+SHoRdVyX5 J6rI7okc4+b571a7RXD5UhS9dlVRVVAtrU9ANSLqPTQKGVxHrqD39XSw8hxK61pw8p90pg4G /N3iuWEvyt+t0SxDDkClnGsDyRhlUyEWYFEoBrrCizbmahOUwqkJbNMfzj5Y7n7OIJOxNRkB IBOjPdF26dMP69BwePQao1M8Acrrex9sAHYjQGyVmReRjVEtv9iG4DoTsnIR3amKVk6si4Ea X/mrapJqSCcBUVYUFH8M7bsm4CSxier5ofy8jTEa/CfvkqpKThTMCQPNZKY7hke5qEq1CBk2 wxhX48ZrJEFf1v3NuV3OimgsF2odzieNABEBAAHCwXwEGAEKACYCGwwWIQSpQNQ0mSwujpkQ PVAiT6fnzIKmZAUCZ8gcVAUJFhTonwAKCRAiT6fnzIKmZLY8D/9uo3Ut9yi2YCuASWxr7QQZ lJCViArjymbxYB5NdOeC50/0gnhK4pgdHlE2MdwF6o34x7TPFGpjNFvycZqccSQPJ/gibwNA zx3q9vJT4Vw+YbiyS53iSBLXMweeVV1Jd9IjAoL+EqB0cbxoFXvnjkvP1foiiF5r73jCd4PR rD+GoX5BZ7AZmFYmuJYBm28STM2NA6LhT0X+2su16f/HtummENKcMwom0hNu3MBNPUOrujtW khQrWcJNAAsy4yMoJ2Lw51T/5X5Hc7jQ9da9fyqu+phqlVtn70qpPvgWy4HRhr25fCAEXZDp xG4RNmTm+pqorHOqhBkI7wA7P/nyPo7ZEc3L+ZkQ37u0nlOyrjbNUniPGxPxv1imVq8IyycG AN5FaFxtiELK22gvudghLJaDiRBhn8/AhXc642/Z/yIpizE2xG4KU4AXzb6C+o7LX/WmmsWP Ly6jamSg6tvrdo4/e87lUedEqCtrp2o1xpn5zongf6cQkaLZKQcBQnPmgHO5OG8+50u88D9I rywqgzTUhHFKKF6/9L/lYtrNcHU8Z6Y4Ju/MLUiNYkmtrGIMnkjKCiRqlRrZE/v5YFHbayRD dJKXobXTtCBYpLJM4ZYRpGZXne/FAtWNe4KbNJJqxMvrTOrnIatPj8NhBVI0RSJRsbilh6TE m6M14QORSWTLRg== In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: E64CE140008 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: 3sa74ab5668qz8cqknmykijmb5h11697 X-HE-Tag: 1769156696-649178 X-HE-Meta: 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 xDVXfP2H xZOEntcQFUTM/v4eGHYyn/1QI8I3YJog3mn/hNwIGb6hwDDC/bS0nZywVRhnelLpz45KdE+B6eAF+eAG+8hPmjQohAUAXWGPH7buay0txj3rpqPAfUAmllR3aVMJbzJY5VHXZX4OUo5brSksDH63lOGmC/hUJX3wYr0yhICUnchfFTlqhpLSGAvVhvxYOwVn/BIOV1uTAlWz730JlNfTdZA3/+CZM6uOfcAgErdQwIc9BQn1dIjMnVoKJsCVpSeS/EKTsFPmM9WFRbT/jdQsNag8WQNMxhafEwNys9w34x3Q5afzPD2gjovUPp4+jEcV5LhwKlOXG3iw5DNkRu0k66nVLZf/QLVxKiWiihKtxkjH0VOwqoSVqw5QW/A== 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 1/22/26 20:31, Suren Baghdasaryan wrote: >> > + int oldcnt; >> > + bool detached; >> > + >> > + detached = __refcount_dec_and_test(&vma->vm_refcnt, &oldcnt); >> > + if (refcnt) >> > + *refcnt = oldcnt - 1; >> > + return detached; > > IIUC there is always a connection between detached and *refcnt > resulting value. If detached==true then the resulting *refcnt has to > be 0. If so, __vma_refcount_put() can simply return (oldcnt - 1) as > new count: > > static inline int __vma_refcount_put(struct vm_area_struct *vma) > { > int oldcnt; > > __refcount_dec_and_test(&vma->vm_refcnt, &oldcnt); > return oldcnt - 1; > } > > And later: > > newcnt = __vma_refcount_put(&vma->vm_refcnt); > detached = newcnt == 0; If we go that way (both ways are fine with me) I'd suggest we rename the function to __vma_refcount_put_return to make this more obvious. (c.f. atomic_dec_return, lockref_put_return).