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Shutemov" , Andrew Morton Cc: Mike Rapoport , David Hildenbrand , Vlastimil Babka , Mel Gorman , Tom Lendacky , "Kalra, Ashish" , Rick Edgecombe , linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, Srikanth Aithal References: <20250329171030.3942298-1-kirill.shutemov@linux.intel.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; keydata= xsFNBE6HMP0BEADIMA3XYkQfF3dwHlj58Yjsc4E5y5G67cfbt8dvaUq2fx1lR0K9h1bOI6fC oAiUXvGAOxPDsB/P6UEOISPpLl5IuYsSwAeZGkdQ5g6m1xq7AlDJQZddhr/1DC/nMVa/2BoY 2UnKuZuSBu7lgOE193+7Uks3416N2hTkyKUSNkduyoZ9F5twiBhxPJwPtn/wnch6n5RsoXsb ygOEDxLEsSk/7eyFycjE+btUtAWZtx+HseyaGfqkZK0Z9bT1lsaHecmB203xShwCPT49Blxz VOab8668QpaEOdLGhtvrVYVK7x4skyT3nGWcgDCl5/Vp3TWA4K+IofwvXzX2ON/Mj7aQwf5W iC+3nWC7q0uxKwwsddJ0Nu+dpA/UORQWa1NiAftEoSpk5+nUUi0WE+5DRm0H+TXKBWMGNCFn c6+EKg5zQaa8KqymHcOrSXNPmzJuXvDQ8uj2J8XuzCZfK4uy1+YdIr0yyEMI7mdh4KX50LO1 pmowEqDh7dLShTOif/7UtQYrzYq9cPnjU2ZW4qd5Qz2joSGTG9eCXLz5PRe5SqHxv6ljk8mb ApNuY7bOXO/A7T2j5RwXIlcmssqIjBcxsRRoIbpCwWWGjkYjzYCjgsNFL6rt4OL11OUF37wL QcTl7fbCGv53KfKPdYD5hcbguLKi/aCccJK18ZwNjFhqr4MliQARAQABzUVEYXZpZCBDaHJp c3RvcGhlciBIYW5zZW4gKEludGVsIFdvcmsgQWRkcmVzcykgPGRhdmUuaGFuc2VuQGludGVs LmNvbT7CwXgEEwECACIFAlQ+9J0CGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEGg1 lTBwyZKwLZUP/0dnbhDc229u2u6WtK1s1cSd9WsflGXGagkR6liJ4um3XCfYWDHvIdkHYC1t MNcVHFBwmQkawxsYvgO8kXT3SaFZe4ISfB4K4CL2qp4JO+nJdlFUbZI7cz/Td9z8nHjMcWYF IQuTsWOLs/LBMTs+ANumibtw6UkiGVD3dfHJAOPNApjVr+M0P/lVmTeP8w0uVcd2syiaU5jB aht9CYATn+ytFGWZnBEEQFnqcibIaOrmoBLu2b3fKJEd8Jp7NHDSIdrvrMjYynmc6sZKUqH2 I1qOevaa8jUg7wlLJAWGfIqnu85kkqrVOkbNbk4TPub7VOqA6qG5GCNEIv6ZY7HLYd/vAkVY E8Plzq/NwLAuOWxvGrOl7OPuwVeR4hBDfcrNb990MFPpjGgACzAZyjdmYoMu8j3/MAEW4P0z F5+EYJAOZ+z212y1pchNNauehORXgjrNKsZwxwKpPY9qb84E3O9KYpwfATsqOoQ6tTgr+1BR CCwP712H+E9U5HJ0iibN/CDZFVPL1bRerHziuwuQuvE0qWg0+0SChFe9oq0KAwEkVs6ZDMB2 P16MieEEQ6StQRlvy2YBv80L1TMl3T90Bo1UUn6ARXEpcbFE0/aORH/jEXcRteb+vuik5UGY 5TsyLYdPur3TXm7XDBdmmyQVJjnJKYK9AQxj95KlXLVO38lczsFNBFRjzmoBEACyAxbvUEhd GDGNg0JhDdezyTdN8C9BFsdxyTLnSH31NRiyp1QtuxvcqGZjb2trDVuCbIzRrgMZLVgo3upr MIOx1CXEgmn23Zhh0EpdVHM8IKx9Z7V0r+rrpRWFE8/wQZngKYVi49PGoZj50ZEifEJ5qn/H Nsp2+Y+bTUjDdgWMATg9DiFMyv8fvoqgNsNyrrZTnSgoLzdxr89FGHZCoSoAK8gfgFHuO54B lI8QOfPDG9WDPJ66HCodjTlBEr/Cwq6GruxS5i2Y33YVqxvFvDa1tUtl+iJ2SWKS9kCai2DR 3BwVONJEYSDQaven/EHMlY1q8Vln3lGPsS11vSUK3QcNJjmrgYxH5KsVsf6PNRj9mp8Z1kIG qjRx08+nnyStWC0gZH6NrYyS9rpqH3j+hA2WcI7De51L4Rv9pFwzp161mvtc6eC/GxaiUGuH BNAVP0PY0fqvIC68p3rLIAW3f97uv4ce2RSQ7LbsPsimOeCo/5vgS6YQsj83E+AipPr09Caj 0hloj+hFoqiticNpmsxdWKoOsV0PftcQvBCCYuhKbZV9s5hjt9qn8CE86A5g5KqDf83Fxqm/ vXKgHNFHE5zgXGZnrmaf6resQzbvJHO0Fb0CcIohzrpPaL3YepcLDoCCgElGMGQjdCcSQ+Ci FCRl0Bvyj1YZUql+ZkptgGjikQARAQABwsFfBBgBAgAJBQJUY85qAhsMAAoJEGg1lTBwyZKw l4IQAIKHs/9po4spZDFyfDjunimEhVHqlUt7ggR1Hsl/tkvTSze8pI1P6dGp2XW6AnH1iayn yRcoyT0ZJ+Zmm4xAH1zqKjWplzqdb/dO28qk0bPso8+1oPO8oDhLm1+tY+cOvufXkBTm+whm +AyNTjaCRt6aSMnA/QHVGSJ8grrTJCoACVNhnXg/R0g90g8iV8Q+IBZyDkG0tBThaDdw1B2l asInUTeb9EiVfL/Zjdg5VWiF9LL7iS+9hTeVdR09vThQ/DhVbCNxVk+DtyBHsjOKifrVsYep WpRGBIAu3bK8eXtyvrw1igWTNs2wazJ71+0z2jMzbclKAyRHKU9JdN6Hkkgr2nPb561yjcB8 sIq1pFXKyO+nKy6SZYxOvHxCcjk2fkw6UmPU6/j/nQlj2lfOAgNVKuDLothIxzi8pndB8Jju KktE5HJqUUMXePkAYIxEQ0mMc8Po7tuXdejgPMwgP7x65xtfEqI0RuzbUioFltsp1jUaRwQZ MTsCeQDdjpgHsj+P2ZDeEKCbma4m6Ez/YWs4+zDm1X8uZDkZcfQlD9NldbKDJEXLIjYWo1PH hYepSffIWPyvBMBTW2W5FRjJ4vLRrJSUoEfJuPQ3vW9Y73foyo/qFoURHO48AinGPZ7PC7TF vUaNOTjKedrqHkaOcqB185ahG2had0xnFsDPlx5y In-Reply-To: <20250329171030.3942298-1-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 1CE571C000C X-Stat-Signature: 784dc8iuoty3d1u7grpy6m8w74jiqqw6 X-HE-Tag: 1743448031-398705 X-HE-Meta: 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 KNnIV4Y8 as9z2eNo81ONLGpriEn1QtMYPTNmxd9hWZaAe7K0CRoUS4I66PZpp463k9k04325Q52QpjpBPgyZkgo2fCe6tqhwop4cRl8Tb9WhyIHwVjFn/t1vUF9tNlOWZx4eG/1L0E3o5K5PBePLpTm/dB1n0Vh7rXXUtcIlpP83NXo/b/y/9FBpZNZzk5cIMPQggPf2Bji4EZtwncUquk/cPjlTDZnd2pR+vVNPFFK10W9b1f5feChTNIg0/UkE4YMs5V2DZNZcu 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 3/29/25 10:10, Kirill A. Shutemov wrote: > + if (system_wq) > + schedule_work(&zone->unaccepted_cleanup); > + else > + unaccepted_cleanup_work(&zone->unaccepted_cleanup); > + } > } The 'system_wq' check seems like an awfully big hack. No other schedule_work() user does anything similar that I can find across the tree. Instead of hacking in some internal state, could you use 'system_state', like: if (system_state == SYSTEM_BOOTING) unaccepted_cleanup_work(&zone->unaccepted_cleanup); else schedule_work(&zone->unaccepted_cleanup); The other method would be to make it more opportunistic? Basically, detect when it might deadlock: bool try_to_dec() { if (!cpus_read_trylock()) return false; static_branch_dec_cpuslocked(&zones_with_unaccepted_pages); cpus_read_unlock(); return true; } That still requires a bit in the zone to say whether the static_branch_dec() was deferred or not, though. It's kinda open-coding schedule_work().