From b4c11c139717729b8257ee9382d4e5ed713d4dde Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 7 Dec 2014 00:44:00 +0100 Subject: libarchive: add capability to unpack to mem.buffer The performance and number of processes for a "depmod -a" with gzipped modules was abysmal. This patch adds a code path without fork, benefiting all users of xmalloc_open_zipped_read_close. "modinfo radeon.ko.gz", a single-file reader, got 30% faster. "depmod -a", which used to fork over 800 times, got 20% faster. Heavily based on a patch by Lauri Kasanen function old new delta setup_transformer_on_fd - 159 +159 transformer_write - 122 +122 fork_transformer - 112 +112 xmalloc_open_zipped_read_close 63 118 +55 read_bunzip 1866 1896 +30 xtransformer_write - 19 +19 unzip_main 2449 2462 +13 bbunpack 755 766 +11 unpack_lzma_stream 2717 2723 +6 unpack_xz_stream 2393 2397 +4 unpack_Z_stream 1173 1175 +2 inflate_unzip 111 105 -6 check_signature16 70 63 -7 unpack_bz2_stream 359 349 -10 unpack_unxz 12 - -12 unpack_unlzma 12 - -12 unpack_uncompress 12 - -12 unpack_gunzip 12 - -12 unpack_bunzip2 12 - -12 open_transformer 106 92 -14 inflate_unzip_internal 1945 1916 -29 unpack_gz_stream 693 655 -38 open_zipped 89 47 -42 setup_unzip_on_fd 142 53 -89 ------------------------------------------------------------------------------ (add/remove: 4/5 grow/shrink: 7/8 up/down: 533/-295) Total: 238 bytes Signed-off-by: Denys Vlasenko --- archival/unzip.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'archival/unzip.c') diff --git a/archival/unzip.c b/archival/unzip.c index c622bde..38a07e2 100644 --- a/archival/unzip.c +++ b/archival/unzip.c @@ -283,7 +283,9 @@ static void unzip_extract(zip_header_t *zip_header, int dst_fd) transformer_state_t xstate; init_transformer_state(&xstate); xstate.bytes_in = zip_header->formatted.cmpsize; - if (inflate_unzip(&xstate, zip_fd, dst_fd) < 0) + xstate.src_fd = zip_fd; + xstate.dst_fd = dst_fd; + if (inflate_unzip(&xstate) < 0) bb_error_msg_and_die("inflate error"); /* Validate decompression - crc */ if (zip_header->formatted.crc32 != (xstate.crc32 ^ 0xffffffffL)) { -- cgit v1.1