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charset=us-ascii Content-Disposition: inline In-Reply-To: <20260128-swap-table-p3-v2-9-fe0b67ef0215@tencent.com> X-Stat-Signature: ph9xccwc5qfdycngyzjuywr3sorogusa X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 0C06B140006 X-HE-Tag: 1769675320-251218 X-HE-Meta: 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 3InSfTnd Q0w3DHMyiLM9aN9EgIoMrWdd6+YVmXWuwt1tqZOGvU9KsleJJqgVT5pw6NrwovNNpQQH2Cs+sxOCuz+B+CJIPTbtGLc2lE1kQ9G/WoRVK0A+U+SX+E9YkDSkOrWqDDVwE+7LfUDHQUaMlOPylprwirx6ZRtu/zf4Tev82HtTo+K1U67pkRhsTy4ptlKc+yEksqGXigmt0zeVPEPsLFH2WGpjMRVA/mtfZUP3ZfYGBlEwdS1k= 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 Wed, Jan 28, 2026 at 05:28:33PM +0800, Kairui Song wrote: > From: Kairui Song > index bfafa637c458..751430e2d2a5 100644 > --- a/mm/swap.h > +++ b/mm/swap.h > @@ -37,6 +37,7 @@ struct swap_cluster_info { > u8 flags; > u8 order; > atomic_long_t __rcu *table; /* Swap table entries, see mm/swap_table.h */ > + unsigned long *extend_table; /* For large swap count, protected by ci->lock */ I assume using 'int *' is to save memory on 64-bit architectures (8 bytes -> 4 bytes per entry), which aligns with swp_tb_get_count() returning an int. Regarding the extended reference table. While I agree that a simple array is better for speed, readability and so on, the 2KB overhead (assuming SWAPFILE_CLUSTER=256) might be significant in constrained environments when only a few entries overflow SWP_TB_COUNT_MAX. Have you considered using a resizable hash table(example. or something others) instead? I am curious if this approach could be applicable as a future optimization after the current code is merged. Thanks :) Youngjun Park