From: Barry Song <v-songbaohua@xxxxxxxx> The patchset removes a couple of memcpy in zswap and crypto to improve zswap's performance. Thanks for Chengming Zhou's test and perf data. Quote from Chengming, I just tested these three patches on my server, found improvement in the kernel build testcase on a tmpfs with zswap (lz4 + zsmalloc) enabled. mm-stable 501a06fe8e4c patched real 1m38.028s 1m32.317s user 19m11.482s 18m39.439s sys 19m26.445s 17m5.646s The patchset is based on mm-stable. Barry Song (3): crypto: introduce acomp_is_async to expose if a acomp has a scomp backend mm/zswap: remove the memcpy if acomp is not asynchronous crypto: scompress: remove memcpy if sg_nents is 1 crypto/acompress.c | 8 ++++++++ crypto/scompress.c | 35 ++++++++++++++++++++++++++++------- include/crypto/acompress.h | 9 +++++++++ mm/zswap.c | 6 ++++-- 4 files changed, 49 insertions(+), 9 deletions(-) -- 2.34.1