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Howlett" , Harry Yoo , Petr Tesarik , Christoph Lameter , David Rientjes , Roman Gushchin , Hao Li , Andrew Morton , Uladzislau Rezki , Suren Baghdasaryan , Sebastian Andrzej Siewior , Alexei Starovoitov , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, bpf@vger.kernel.org, kasan-dev@googlegroups.com References: <20260123-sheaves-for-all-v4-0-041323d506f7@suse.cz> <20260123-sheaves-for-all-v4-8-041323d506f7@suse.cz> <7dk5q3mbusqlklpk3ja57upbhkhhg3bpueh4nemuthesmwpgnk@zkk4fqug3cwx> 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: <7dk5q3mbusqlklpk3ja57upbhkhhg3bpueh4nemuthesmwpgnk@zkk4fqug3cwx> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: BF05D40005 X-Stat-Signature: d53muni6kd844o1jxer61bgt7z91bf6h X-HE-Tag: 1769675121-985762 X-HE-Meta: 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 EM+ehyTN LEibcq4ZnrwWJ/Whzy8v8jJP8Kq1T+Yx6SEqsgJEvQ6phgmM/TEdlyfA8B+hCs8pbyY5EvlJ2M8mBeTpa0K54HiPoo323z0na5hecfkCDKe2u0mv+eYDvXBQ5dNwQD4408yd4NHaV1yGueiyI4UW/ESy7c0ClKP+RxQzIP1X4WkXqJb8bJpdlm1LpjKl7e6eCqSwvMqE6srMCMAZafaYBZZlxiAh1adipeSk2HkNbbmFlwXLKmdKf2UIWdNEJARq/ru/AxsbhheZ+llGr1Pdf4kRslAiJZlsLf+uqrYu3DqECiAQ4iSrikkNY6BLdWrPXgh7D9esyhX7UQJk4F/TgGMgCroDEaMeXnC+0IudSCdIuBh6EeipQ8ZUxTcUHeRaUv6La 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 1/27/26 18:36, Liam R. Howlett wrote: > * Vlastimil Babka [260123 01:54]: >> Before we enable percpu sheaves for kmalloc caches, we need to make sure >> kmalloc_nolock() and kfree_nolock() will continue working properly and >> not spin when not allowed to. >> >> Percpu sheaves themselves use local_trylock() so they are already >> compatible. We just need to be careful with the barn->lock spin_lock. >> Pass a new allow_spin parameter where necessary to use >> spin_trylock_irqsave(). >> >> In kmalloc_nolock_noprof() we can now attempt alloc_from_pcs() safely, >> for now it will always fail until we enable sheaves for kmalloc caches >> next. Similarly in kfree_nolock() we can attempt free_to_pcs(). >> >> Reviewed-by: Suren Baghdasaryan >> Reviewed-by: Harry Yoo >> Reviewed-by: Hao Li >> Signed-off-by: Vlastimil Babka > > I'd rather have a helper that _mayspin() or something. That way, when > we know we need to or don't want to, we avoid extra instructions. We > can also avoid passing true/false and complicating the interface when > it's not necessary. Can you elaborate a bit more how the helper looks like and it's used? I don't follow immediately. We do have the helper for checking gfp flags to extract mayspin, but that wouldn't avoid extra instructions so you must be thinking of something else. > The way it is written works as well, though. > > Reviewed-by: Liam R. Howlett Thanks!