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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240726203110.1577216-4-roman.gushchin@linux.dev> X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 60B014000F X-Stat-Signature: 56yj55wjcon3yj4qqydjy9i7c489ydcb X-Rspam-User: X-HE-Tag: 1722035472-981622 X-HE-Meta: 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 wfkrBc2Y 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 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 Fri, Jul 26, 2024 at 08:31:10PM +0000, Roman Gushchin wrote: > When a page_counter structure is initialized, there is no need to > use an atomic set operation to initialize the usage counter because > at this point the structure is not visible to anybody else. > ATOMIC_LONG_INIT() is what should be used in such cases. > > Signed-off-by: Roman Gushchin > --- > include/linux/page_counter.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/page_counter.h b/include/linux/page_counter.h > index cf837d0f8ed1..5da11392b382 100644 > --- a/include/linux/page_counter.h > +++ b/include/linux/page_counter.h > @@ -53,7 +53,7 @@ static inline void page_counter_init(struct page_counter *counter, > struct page_counter *parent, > bool protection_support) > { > - atomic_long_set(&counter->usage, 0); > + counter->usage = (atomic_long_t)ATOMIC_LONG_INIT(0); Pretty cool that ATOMIC_LONG_INIT() return value needs a cast to atomic_long_t! ^_^ Acked-by: Johannes Weiner