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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 3BB79C0005 X-Stat-Signature: uz9r6y1ije5xn9e6oiqxikg3j4w86jmb X-Rspam-User: X-HE-Tag: 1779182318-785623 X-HE-Meta: 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 HaMiHXHC 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, May 19, 2026 at 04:08:35PM +0900, YoungJun Park wrote: > On Mon, May 18, 2026 at 11:30:52PM -0700, Christoph Hellwig wrote: > > Hi Christoph! > > > Nothing in this patch ever sets the new flag. And I'd rather not > > I defined a new flag that can be set at swapon timing. Is your concern > that there is no mention of the user-space flag setting part? Heh. My main concert was that I assumed it's a kernel-only flag as SWAP_FLAG_* aren't defined in a uapi header. But now that I know that they are user passed flag, my concern is that this is not something that should be exposed to the user because it is a depply internal implementation detail. > > > add new weird bdev hooks for zram when we really need to consolidate > > the compressed swap logic in the core swap code. > > Are you mentioning we consolidate the same data pattern logic (including > compressed swap) into the core swap code? That is the plan based on my understanding of the LSF/MM session. > I am curious about what direction you have in mind. I can think of three > possible approaches. > > - Handle it in individual devices > > Can be optimized for each device. Currently, the swap layer > handles zero pages but not same data patterns, causing a mismatch. My > patch aims to resolve this. If we prefer this direction, we could even > remove the zero page check from the swap layer and let individual swap > devices handle it. I don't think devices should care about this at all. compression and dedup is core functionality that does not depend on the underlying device. > I wonder which direction you are considering. Please look at all the ongoing discussions on the linux-mm list.