On Tue, Jun 04, 2019 at 03:43:26PM -0700, Andrew Morton wrote: > On Mon, 3 Jun 2019 14:32:03 +0530 Maninder Singh <maninder1.s@xxxxxxxxxxx> wrote: > > > currently params structure is passed in all functions, which increases > > stack usage in all the function and lead to stack overflow on target like > > ARM with kernel stack size of 8 KB so better to pass pointer. > > > > Checked for ARM: > > > > Original Patched > > Call FLow Size: 1264 1040 > > .... > > (HUF_sort) -> 296 > > (HUF_buildCTable_wksp) -> 144 > > (HUF_compress4X_repeat) -> 88 > > (ZSTD_compressBlock_internal) -> 200 > > (ZSTD_compressContinue_internal)-> 136 -> 88 > > (ZSTD_compressCCtx) -> 192 -> 64 > > (zstd_compress) -> 144 -> 96 > > (crypto_compress) -> 32 > > (zcomp_compress) -> 32 > > .... > > > > Signed-off-by: Maninder Singh <maninder1.s@xxxxxxxxxxx> > > Signed-off-by: Vaneet Narang <v.narang@xxxxxxxxxxx> > > > > You missed btrfs. This needs review, please - particularly the > kernel-wide static ZSTD_parameters in zstd_get_btrfs_parameters(). > > The base patch is here: > > http://lkml.kernel.org/r/1559552526-4317-2-git-send-email-maninder1.s@xxxxxxxxxxx > > --- a/fs/btrfs/zstd.c~zstd-pass-pointer-rathen-than-structure-to-functions-fix > +++ a/fs/btrfs/zstd.c > @@ -27,15 +27,17 @@ > /* 307s to avoid pathologically clashing with transaction commit */ > #define ZSTD_BTRFS_RECLAIM_JIFFIES (307 * HZ) > > -static ZSTD_parameters zstd_get_btrfs_parameters(unsigned int level, > +static ZSTD_parameters *zstd_get_btrfs_parameters(unsigned int level, > size_t src_len) > { > - ZSTD_parameters params = ZSTD_getParams(level, src_len, 0); > + static ZSTD_parameters params; > + > + params = ZSTD_getParams(level, src_len, 0); No thats' broken, the params can't be static as it depends on level and src_len. What happens if there are several requests in parallel with eg. different levels? Would be really great if the mailinglist is CCed when the code is changed in a non-trivial way.
