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b=Q220K7Iy8wFQmyUhyBCCdv/fayfubm5a7CIE4/5PObfAA/WU1e1xOqUDx0VwaaAg6 jpxHAdlDo4giFRoHthXnNq2b+OoYgI68fbp6mUUG9TK+oftRf+FuJIxD4h7lVZVqMO D+FSYd5pBWk+JOPgWSrdP01rFmtSKXfFKxACcb4gErSzZ8/ZQ3a7DIvKtcC8UBUN0u u1C7Q7RwBNjRfuxTW55JMd34rEUL1AUXS7NQo2wDrwF1r9qSoN5vbANI8KC2Ejw1BB JHYkkT2xYLoUwNEhjC2Q9E4i6QI9rjLfFSzn3+ufoDWVrdIg32Xk4rXO4zj4+81TT6 ITaAnvn/CywYw== From: SeongJae Park To: lirongqing Cc: SeongJae Park , Jonathan Corbet , Shuah Khan , Vlastimil Babka , Harry Yoo , Andrew Morton , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Matthew Wilcox , Usama Arif Subject: Re: [PATCH v3] mm/mempool: Untangle CONFIG_SLUB_DEBUG_ON abuse and switch to static key Date: Fri, 12 Jun 2026 17:22:06 -0700 Message-ID: <20260613002207.1198-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260604110318.2089-1-lirongqing@baidu.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 3ED78140003 X-Stat-Signature: xqxym9wx78sas1xpdokrfgrqfs19oexb X-Rspam-User: X-HE-Tag: 1781310137-676643 X-HE-Meta: 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 qi7MJvGN 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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 Thu, 4 Jun 2026 19:03:18 +0800 lirongqing wrote: > From: Li RongQing > > The mempool subsystem historically wrapped its debugging logic inside an > merely defines compile-time defaults for SLUB and caused two flaws: > > 1. On production kernels where CONFIG_SLUB_DEBUG=y but > CONFIG_SLUB_DEBUG_ON=n, mempool debugging was completely compiled out > at compile time. > 2. On kernels with CONFIG_SLUB_DEBUG_ON=y, mempool debugging stayed active > even if a user explicitly disabled slub debugging at boot time. > > Clean up this mess by removing the #ifdef and switching to a runtime static > key (mempool_debug_enabled), allowing mempool debugging to be toggled > cleanly via its own boot parameter. Makes sense to me. > > Suggested-by: Vlastimil Babka (SUSE) > Signed-off-by: Li RongQing > Cc: Vlastimil Babka > Cc: Harry Yoo > Cc: Andrew Morton > Cc: Hao Li > Cc: Christoph Lameter > Cc: David Rientjes > Cc: Roman Gushchin > Cc: Matthew Wilcox > Cc: Usama Arif Reviewed-by: SeongJae Park Thanks, SJ [...]