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Content-Language: en-US To: lvqian@nfschina.com, cl@linux.co, penberg@kernel.org, rientjes@google.com, kim@lge.com, akpm@linux-foundation.org, roman.gushchin@linux.dev, 42.hyeyoo@gmail.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20230111083102.111535-1-lvqian@nfschina.com> From: Vlastimil Babka In-Reply-To: <20230111083102.111535-1-lvqian@nfschina.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 5260A1C000D X-Stat-Signature: kuggyjpy9u91g5d6zx8e85dsshb573p3 X-HE-Tag: 1673428026-389881 X-HE-Meta: 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 nd8FMQHj ftKHiOcVtHtuwoKE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.011407, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 1/11/23 09:31, lvqian@nfschina.com wrote: > From: lvqian The subject line is long, e.g. the second sentence should be part of body, not subject. Note the usual wording is "if statement" not "judgement" > Remove the if judgment and return the result directly to reduce assembly statements. I'm pretty sure there will be no effect on generated code/assembly, so it should be purely about the C code readability. That's somewhat subjective, but I think it's acceptable in this case. > diff --git a/mm/slab.c b/mm/slab.c > index 7a269db050ee..713265fe2dea 100644 > --- a/mm/slab.c > +++ b/mm/slab.c > @@ -1415,11 +1415,8 @@ static void kmem_rcu_free(struct rcu_head *head) > #if DEBUG > static bool is_debug_pagealloc_cache(struct kmem_cache *cachep) > { > - if (debug_pagealloc_enabled_static() && OFF_SLAB(cachep) && > - (cachep->size % PAGE_SIZE) == 0) > - return true; > - > - return false; > + return debug_pagealloc_enabled_static() && OFF_SLAB(cachep) && > + ((cachep->size % PAGE_SIZE) == 0); > } > > #ifdef CONFIG_DEBUG_PAGEALLOC