update $GIT_INDEX_FILE when there are racily clean entries
Traditional "opportunistic index update" done by read-only "diff" and "status" was about updating cached lstat(2) information in the index for the next round. We missed another obvious optimization opportunity: when there are racily clean entries that will cease to be racily clean by updating $GIT_INDEX_FILE. Detect that case and write $GIT_INDEX_FILE out to give it a newer timestamp. Noticed by Lasse Makholm by stracing "git status" in a fresh checkout and counting the number of open(2) calls. Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano committed
Mar 21, 2011 at 10:18 UTC
483fbe2b7cb89ddcf700a677735d21aa176bc5a6
1 file changed
+14
-1
read-cache.c
+14
-1
@@ -1545,12 +1545,25 @@ static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce)
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return result;
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}
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+static int has_racy_timestamp(struct index_state *istate)
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+{
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+ int entries = istate->cache_nr;
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+ int i;
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+
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+ for (i = 0; i < entries; i++) {
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+ struct cache_entry *ce = istate->cache[i];
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+ if (is_racy_timestamp(istate, ce))
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+ return 1;
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+ }
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+ return 0;
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+}
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+
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/*
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* Opportunisticly update the index but do not complain if we can't
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*/
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void update_index_if_able(struct index_state *istate, struct lock_file *lockfile)
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{
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- if (istate->cache_changed &&
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+ if ((istate->cache_changed || has_racy_timestamp(istate)) &&
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!write_index(istate, lockfile->fd))
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commit_locked_index(lockfile);
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else