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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: zm9ojia4xo5cfbybpu8broyr78a7iitk X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 3469C80017 X-HE-Tag: 1706861906-286437 X-HE-Meta: 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 NSvj7Z0j 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000018, 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 2024/2/2 01:55, Johannes Weiner wrote: > On Thu, Feb 01, 2024 at 03:49:04PM +0000, Chengming Zhou wrote: >> cat /sys/kernel/debug/zswap/duplicate_entry >> 2086447 >> >> When testing, the duplicate_entry value is very high, but no warning >> message in the kernel log. From the comment of duplicate_entry >> "Duplicate store was encountered (rare)", it seems something goes wrong. >> >> Actually it's incremented in the beginning of zswap_store(), which found >> its zswap entry has already on the tree. And this is a normal case, >> since the folio could leave zswap entry on the tree after swapin, >> later it's dirtied and swapout/zswap_store again, found its original >> zswap entry. (Maybe we can reuse it instead of invalidating it?) > > Probably not worth it, especially after the next patch. You are right, not worth it. > >> So duplicate_entry should be only incremented in the real bug case, >> which already have "WARN_ON(1)", it looks redundant to count bug case, >> so this patch just remove it. >> >> Signed-off-by: Chengming Zhou > > Either way, I agree that the WARN_ON() is more useful to point out a > bug than a counter. > > Acked-by: Johannes Weiner Thanks!