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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 29F3B100011 X-Rspam-User: X-Stat-Signature: yhjtnrfrcdkfce1xzmzdhodmbsptq8qq X-HE-Tag: 1713773049-954089 X-HE-Meta: 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 UM1BRq93 PU2vE1Ru8KEDV0aSa3SmeLXBMDw15pPvqOPky53qR+oi2w5QQ4vyIShdjjSAt5+0uAcqJBBCIZJjTUhBM20jXkujgggwwHMDW/MMZQV3PKYAz1KUkE1veZTjB4ZtB9mM5lmw3W6bV/NW+055uyQV2CwtAVawcUH4TH/41T0Y3QFqSMoVLeFJdwctRyQ== 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 4/22/24 15:47, David Hildenbrand wrote: > On 22.04.24 09:42, zhenwei pi wrote: >> All the VM events related statistics have dependence on >> 'CONFIG_VM_EVENT_COUNTERS', once any stack variable is required by any >> VM events in future, we would have codes like: >>   #ifdef CONFIG_VM_EVENT_COUNTERS >>        unsigned long foo; >>   #endif >>        ... >>   #ifdef CONFIG_VM_EVENT_COUNTERS >>        foo = events[XXX] + events[YYY]; >>        update_stat(vb, idx++, VIRTIO_BALLOON_S_XXX, foo); >>   #endif >> >> Separate vm events into a single function, also remove > > Why not simply use __maybe_unused for that variable? > 1> static unsigned int update_balloon_stats() { unsigned __maybe_unused long foo; ... #ifdef CONFIG_VM_EVENT_COUNTERS foo = events[XXX] + events[YYY]; update_stat(vb, idx++, VIRTIO_BALLOON_S_XXX, foo); #endif } 2> static inline unsigned int update_balloon_vm_stats() { #ifdef CONFIG_VM_EVENT_COUNTERS unsigned long foo; foo = events[XXX] + events[YYY]; update_stat(vb, idx++, VIRTIO_BALLOON_S_XXX, foo); #endif } From the point of my view, I don't need to compile code in my brain when reading codes for case 2. :) -- zhenwei pi