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libarchive: add capability to unpack to mem.buffer

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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 <curaga@operamail.com>

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 <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko
2014-12-07 00:44:00 +01:00
parent e7800f351a
commit b4c11c1397
14 changed files with 243 additions and 127 deletions
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30
archival/libarchive/decompress_gunzip.c
View File

@@ -971,7 +971,7 @@ static int inflate_get_next_window(STATE_PARAM_ONLY)
/* Called from unpack_gz_stream() and inflate_unzip() */
static IF_DESKTOP(long long) int
inflate_unzip_internal(STATE_PARAM int in, int out)
inflate_unzip_internal(STATE_PARAM transformer_state_t *xstate)
{
IF_DESKTOP(long long) int n = 0;
ssize_t nwrote;
@@ -980,7 +980,7 @@ inflate_unzip_internal(STATE_PARAM int in, int out)
gunzip_window = xmalloc(GUNZIP_WSIZE);
gunzip_outbuf_count = 0;
gunzip_bytes_out = 0;
gunzip_src_fd = in;
gunzip_src_fd = xstate->src_fd;
/* (re) initialize state */
method = -1;
@@ -1002,9 +1002,8 @@ inflate_unzip_internal(STATE_PARAM int in, int out)
while (1) {
int r = inflate_get_next_window(PASS_STATE_ONLY);
nwrote = full_write(out, gunzip_window, gunzip_outbuf_count);
if (nwrote != (ssize_t)gunzip_outbuf_count) {
bb_perror_msg("write");
nwrote = transformer_write(xstate, gunzip_window, gunzip_outbuf_count);
if (nwrote == (ssize_t)-1) {
n = -1;
goto ret;
}
@@ -1034,7 +1033,7 @@ inflate_unzip_internal(STATE_PARAM int in, int out)
/* For unzip */
IF_DESKTOP(long long) int FAST_FUNC
inflate_unzip(transformer_state_t *xstate, int in, int out)
inflate_unzip(transformer_state_t *xstate)
{
IF_DESKTOP(long long) int n;
DECLARE_STATE;
@@ -1045,7 +1044,7 @@ inflate_unzip(transformer_state_t *xstate, int in, int out)
// bytebuffer_max = 0x8000;
bytebuffer_offset = 4;
bytebuffer = xmalloc(bytebuffer_max);
n = inflate_unzip_internal(PASS_STATE in, out);
n = inflate_unzip_internal(PASS_STATE xstate);
free(bytebuffer);
xstate->crc32 = gunzip_crc;
@@ -1169,8 +1168,7 @@ static int check_header_gzip(STATE_PARAM transformer_state_t *xstate)
}
}
if (xstate)
xstate->mtime = SWAP_LE32(header.formatted.mtime);
xstate->mtime = SWAP_LE32(header.formatted.mtime);
/* Read the header checksum */
if (header.formatted.flags & 0x02) {
@@ -1182,27 +1180,27 @@ static int check_header_gzip(STATE_PARAM transformer_state_t *xstate)
}
IF_DESKTOP(long long) int FAST_FUNC
unpack_gz_stream(transformer_state_t *xstate, int src_fd, int dst_fd)
unpack_gz_stream(transformer_state_t *xstate)
{
uint32_t v32;
IF_DESKTOP(long long) int total, n;
DECLARE_STATE;
#if !ENABLE_FEATURE_SEAMLESS_Z
if (check_signature16(xstate, src_fd, GZIP_MAGIC))
if (check_signature16(xstate, GZIP_MAGIC))
return -1;
#else
if (xstate && xstate->check_signature) {
if (xstate->check_signature) {
uint16_t magic2;
if (full_read(src_fd, &magic2, 2) != 2) {
if (full_read(xstate->src_fd, &magic2, 2) != 2) {
bad_magic:
bb_error_msg("invalid magic");
return -1;
}
if (magic2 == COMPRESS_MAGIC) {
xstate->check_signature = 0;
return unpack_Z_stream(xstate, src_fd, dst_fd);
return unpack_Z_stream(xstate);
}
if (magic2 != GZIP_MAGIC)
goto bad_magic;
@@ -1215,7 +1213,7 @@ unpack_gz_stream(transformer_state_t *xstate, int src_fd, int dst_fd)
to_read = -1;
// bytebuffer_max = 0x8000;
bytebuffer = xmalloc(bytebuffer_max);
gunzip_src_fd = src_fd;
gunzip_src_fd = xstate->src_fd;
again:
if (!check_header_gzip(PASS_STATE xstate)) {
@@ -1224,7 +1222,7 @@ unpack_gz_stream(transformer_state_t *xstate, int src_fd, int dst_fd)
goto ret;
}
n = inflate_unzip_internal(PASS_STATE src_fd, dst_fd);
n = inflate_unzip_internal(PASS_STATE xstate);
if (n < 0) {
total = -1;
goto ret;