From: Nick Terrell <terrelln@xxxxxx> I'll be sending these patches to Linus through my tree. Just submitting them for comment before I do so. I'm somewhat unsure of the correct workflow for patches I submit myself, so let me know if there is something different I should do. This patch set contains 3 commits: 1. Fixes a minor unused variable warning reported by Kernel test robot [0]. 2. Improves the reported code bloat (-88KB / 374KB) [1] by outlining some functions that are unlikely to be used in performance sensitive workloads. 3. Fixes the reported excess stack usage on parisc [2] by removing -O3 from zstd's compilation flags. -O3 triggered bugs in the hppa-linux-gnu gcc-8 compiler. -O2 performance is acceptable: neutral compression, about -1% decompression speed. We also reduce code bloat (-105KB / 374KB). After this commit our code bloat is cut from 374KB to 105KB with gcc-11. If we wanted to cut the remaining 105KB we'd likely have to trade signicant performance, so I want to say that this is enough for now. We should be able to get further gains without sacrificing speed, but that will take some significant optimization effort, and isn't suitable for a quick fix. I've opened an upstream issue [3] to track the code size, and try to avoid future regressions, and improve it in the long term. [0] https://lore.kernel.org/linux-mm/202111120312.833wII4i-lkp@xxxxxxxxx/T/ [1] https://lkml.org/lkml/2021/11/15/710 [2] https://lkml.org/lkml/2021/11/14/189 [3] https://github.com/facebook/zstd/issues/2867 Signed-off-by: Nick Terrell <terrelln@xxxxxx> v1 -> v2: * (1/3) Update commit message & add a comment. Nick Terrell (3): lib: zstd: Fix unused variable warning lib: zstd: Don't inline functions in zstd_opt.c lib: zstd: Don't add -O3 to cflags lib/zstd/Makefile | 2 -- lib/zstd/common/compiler.h | 7 +++++++ lib/zstd/compress/zstd_compress_superblock.c | 2 ++ lib/zstd/compress/zstd_opt.c | 14 +++++++++++++- 4 files changed, 22 insertions(+), 3 deletions(-) -- 2.33.1
