[PATCH] Remove preemptive allocations.
From: Pierre Habouzit <hidden>
Date: 2016-06-15 22:43:34
Subsystem:
the rest · Maintainer:
Linus Torvalds
Careful profiling shows that we spend more time guessing what pattern allocation will have, whereas we can delay it only at the point where add_rfc2047 will be used and don't allocate huge memory area for the many cases where it's not. Signed-off-by: Pierre Habouzit <redacted> --- commit.c | 35 +++++------------------------------ 1 files changed, 5 insertions(+), 30 deletions(-)
diff --git a/commit.c b/commit.c
index 13af933..85889f9 100644
--- a/commit.c
+++ b/commit.c@@ -501,6 +501,7 @@ static void add_rfc2047(struct strbuf *sb, const char *line, int len, return; needquote: + strbuf_grow(sb, len * 3 + strlen(encoding) + 100); strbuf_addf(sb, "=?%s?q?", encoding); for (i = last = 0; i < len; i++) { unsigned ch = line[i] & 0xFF;
@@ -520,14 +521,6 @@ needquote: strbuf_addstr(sb, "?="); } -static unsigned long bound_rfc2047(unsigned long len, const char *encoding) -{ - /* upper bound of q encoded string of length 'len' */ - unsigned long elen = strlen(encoding); - - return len * 3 + elen + 100; -} - static void add_user_info(const char *what, enum cmit_fmt fmt, struct strbuf *sb, const char *line, enum date_mode dmode, const char *encoding)
@@ -560,8 +553,7 @@ static void add_user_info(const char *what, enum cmit_fmt fmt, struct strbuf *sb add_rfc2047(sb, line, display_name_length, encoding); strbuf_add(sb, name_tail, namelen - display_name_length); strbuf_addch(sb, '\n'); - } - else { + } else { strbuf_addf(sb, "%s: %.*s%.*s\n", what, (fmt == CMIT_FMT_FULLER) ? 4 : 0, filler, namelen, line);
@@ -955,19 +947,12 @@ static void pp_header(enum cmit_fmt fmt, * FULLER shows both authors and dates. */ if (!memcmp(line, "author ", 7)) { - unsigned long len = linelen; - if (fmt == CMIT_FMT_EMAIL) - len = bound_rfc2047(linelen, encoding); - strbuf_grow(sb, len + 80); + strbuf_grow(sb, linelen + 80); add_user_info("Author", fmt, sb, line + 7, dmode, encoding); } - if (!memcmp(line, "committer ", 10) && (fmt == CMIT_FMT_FULL || fmt == CMIT_FMT_FULLER)) { - unsigned long len = linelen; - if (fmt == CMIT_FMT_EMAIL) - len = bound_rfc2047(linelen, encoding); - strbuf_grow(sb, len + 80); + strbuf_grow(sb, linelen + 80); add_user_info("Commit", fmt, sb, line + 10, dmode, encoding); } }
@@ -982,7 +967,6 @@ static void pp_title_line(enum cmit_fmt fmt, int plain_non_ascii) { struct strbuf title; - unsigned long len; strbuf_init(&title, 80);
@@ -1004,16 +988,7 @@ static void pp_title_line(enum cmit_fmt fmt, strbuf_add(&title, line, linelen); } - /* Enough slop for the MIME header and rfc2047 */ - len = bound_rfc2047(title.len, encoding) + 1000; - if (subject) - len += strlen(subject); - if (after_subject) - len += strlen(after_subject); - if (encoding) - len += strlen(encoding); - - strbuf_grow(sb, title.len + len); + strbuf_grow(sb, title.len + 1024); if (subject) { strbuf_addstr(sb, subject); add_rfc2047(sb, title.buf, title.len, encoding);
--
1.5.3.1