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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240220064414.262582-4-21cnbao@gmail.com> X-Rspamd-Queue-Id: 51E7318000D X-Rspam-User: X-Stat-Signature: db6xwi6fn7pcdrbfh443jppyzm7388yu X-Rspamd-Server: rspam01 X-HE-Tag: 1708493699-476470 X-HE-Meta: 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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 Tue, Feb 20, 2024 at 07:44:14PM +1300, Barry Song wrote: > From: Barry Song > > while sg_nents is 1 which is always true for the current kernel > as the only user - zswap is the case, we should remove two big > memcpy. > > Signed-off-by: Barry Song > Tested-by: Chengming Zhou > --- > crypto/scompress.c | 36 +++++++++++++++++++++++++++++------- > 1 file changed, 29 insertions(+), 7 deletions(-) This patch is independent of the other two. Please split it out so I can apply it directly. > @@ -134,13 +135,25 @@ static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir) > scratch = raw_cpu_ptr(&scomp_scratch); > spin_lock(&scratch->lock); > > - scatterwalk_map_and_copy(scratch->src, req->src, 0, req->slen, 0); > + if (sg_nents(req->src) == 1) { > + src = kmap_local_page(sg_page(req->src)) + req->src->offset; What if the SG entry is longer than PAGE_SIZE (or indeed crosses a page boundary)? I think the test needs to be strengthened. Thanks, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt