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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: 574F140006 X-Stat-Signature: 4fi5qg7fpcun68wtft88nspmioxk8rmr X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1774504240-802058 X-HE-Meta: U2FsdGVkX1+sRDxIBVSdtRnTSe47WPN0UIA6FAkS245sQXaCeP8SFC0ecwGu0DZbZ35IhayHcktMUEhwViPlnfskm9XIx2yyIo+azn4ZezxVopfYQkNRd2QKV4a4KRsk57QJm3YKQ/yXEkmfgylTUkECY+mJ/k9GX40Fhz3tHqQVqwJbg+kWQU7TSk0sfQbtXG5wdclvU3dIwjCrT6XtAacZejAal6CZ3VJ8cGtknpE1NzubGLn9Q6Pac6FmyXkGJnwSali7B7tPfkFwANjbTqIimgGuuE+yivUp+gtzIKcURiqoZW72e4N2ZvSCSeoC4yKanYuXajbQTR+PCxztX63nmrLg3UzS/71jM+gs4zjC2jLB1EHjOUPvmvAtuwV7Vs1gmuufszyDfmzs2He5W7d4CFKlIHHQls5q3m8feHBS73dUTFKX26K10CZq75BwCUOplrdSyEH6fwD/jYdHbaFIzY7uzRV7RQmfQ0beBLz/jV9Nflxh6UkaJuWui6Uogj8OXksNIOLyrmVHDF6yfISiEuHhSTZ1U8HTWP3YXe3Np/3l4zLMOfeVy+IXRk4/lBqFTz1WstUfn+VP+nwZuIkmiFQSOOLFd8VEPJKFSCYlOTOFYZDIGecLyJQiVHe8fJK306gX1VtFeCOpIfM9qfDaSJt2obeepjcKlKmo4gy47OZfbZRwBLdQ++z0lxqQyI3swLUySu1wxyA9vgVDSciq6G6keMmO1fzkbxMI/zXm4RAPS7t9iWweWwu775ynCQSy5cVq15G67WCmU3LKpKqU7OkoIlCUNsZVtOzIiVsdtKji0WmfSF3hS6u+zTvVd5LmgO5zT5PphPdFz/J+HvHE++4D1EfHGeEudQOZfaw0k1ET3sdyCpAVqALdaMFD7DliF34b3GDkxWGe1GMREzU9zXq60oc309JkZQGYNZRV/pSV5OIcHZknuf9dh2iee0Jx9f5QbbKkQWzCEDI 84TEeIDQ 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 25, 2026 at 05:13:37PM -0700, Joanne Koong wrote: > Commit 64dd89ae01f2 ("mm/block/fs: remove laptop_mode") removed this > unconditional writeback kick from balance_dirty_pages(): > > if (unlikely(!writeback_in_progress(wb))) > wb_start_background_writeback(wb); Yes, that looks like a bug. > This fixes the issue by kicking off the flusher if wb_dirty exceeds > wb_bg_thresh for strictlimit BDIs. This restores performance back to its > original baseline. What speaks against just reinstating the old-code as-is minus the misleading latop_mode comment?