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Message-ID: References: <20240528121928.i-Gu7Jvg@linutronix.de> <09e085bb-f09e-4901-a2dd-a0b789bb8a4d@kernel.org> <20240528134027.OxDASsS3@linutronix.de> <20240528141341.rz_rytN_@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240528141341.rz_rytN_@linutronix.de> X-Rspamd-Action: no action X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: B2BDEC0020 X-Stat-Signature: f5zjxu8i8xttqr5jmz6sgx8iwj6dtcep X-HE-Tag: 1716974218-153491 X-HE-Meta: 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 2V6CRSLD YOd7OKw4DiHudQNwD7zOgqv5MBPcuv6d8jm1lJ0V2o4ZXa8WTcuiYgrM2RMBXQzR7oCRompDvTvcXo8V1ObVjzCg+UQWsVIVIimx2FHEEayhH9+Rv4zU3QBzwEOLcHCIIhdr4Y41LqvZb13cVkSnc9dpFD12zppZpWJkDtyrGMj7oZ6+cGYVh0csKGyxXCt486YfytJ7up1trCGnUwEtsgZLCxUuO57R4oN2ttj3rmS1Lw8uwTkIr9lUtOLBkuuWLq26JJPCIO9zpRB+6pgONfzvH1loaTEDKjjrTgWe8vDjDGwubOZ4pp4mZCLbnYw3C+ZTiL8NiRarWLuwM39HEXe8Vtn9oTb9C30gyU31Kxlxcx5jTmZ+MgHfgK91NwHObT7Cc 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 Tue 28-05-24 16:13:41, Sebastian Andrzej Siewior wrote: > The assert was introduced in the commit cited below as an insurance that > the semantic is the same after the local_irq_save() has been removed and > the function has been made static. > > The original requirement to disable interrupt was due the modification > of per-CPU counters which require interrupts to be disabled because the > counter update operation is not atomic and some of the counters are > updated from interrupt context. > > All callers of __mod_objcg_mlstate() acquire a lock > (memcg_stock.stock_lock) which disables interrupts on !PREEMPT_RT and > the lockdep assert is satisfied. On PREEMPT_RT the interrupts are not > disabled and the assert triggers. > > The safety of the counter update is already ensured by > VM_WARN_ON_IRQS_ENABLED() which is part of __mod_memcg_lruvec_state() and > does not require yet another check. > > Remove the lockdep assert from __mod_objcg_mlstate(). > > Fixes: 91882c1617c15 ("memcg: simple cleanup of stats update functions") > Link: https://lore.kernel.org/r/20240528121928.i-Gu7Jvg@linutronix.de > Signed-off-by: Sebastian Andrzej Siewior Acked-by: Michal Hocko -- Michal Hocko SUSE Labs