fsmonitor: store fsmonitor bitmap before splitting index

ba1b9cac ("fsmonitor: delay updating state until after split index
is merged", 2017-10-27) resolved the problem of the fsmonitor data
being applied to the non-base index when reading; however, a similar
problem exists when writing the index.  Specifically, writing of the
fsmonitor extension happens only after the work to split the index
has been applied -- as such, the information in the index is only
for the non-"base" index, and thus the extension information
contains only partial data.

When saving, compute the ewah bitmap before the index is split, and
store it in the fsmonitor_dirty field, mirroring the behavior that
occurred during reading.  fsmonitor_dirty is kept from being leaked by
being freed when the extension data is written -- which always happens
precisely once, no matter the split index configuration.

Signed-off-by: Alex Vandiver <alexmv@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Alex Vandiver 2017-11-09 11:58:10 -08:00 committed by Junio C Hamano
parent 6f1dc21d98
commit 3bd28eb299
4 changed files with 36 additions and 9 deletions

View File

@ -54,12 +54,19 @@ int read_fsmonitor_extension(struct index_state *istate, const void *data,
return 0;
}
void fill_fsmonitor_bitmap(struct index_state *istate)
{
int i;
istate->fsmonitor_dirty = ewah_new();
for (i = 0; i < istate->cache_nr; i++)
if (!(istate->cache[i]->ce_flags & CE_FSMONITOR_VALID))
ewah_set(istate->fsmonitor_dirty, i);
}
void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate)
{
uint32_t hdr_version;
uint64_t tm;
struct ewah_bitmap *bitmap;
int i;
uint32_t ewah_start;
uint32_t ewah_size = 0;
int fixup = 0;
@ -73,12 +80,9 @@ void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate)
strbuf_add(sb, &ewah_size, sizeof(uint32_t)); /* we'll fix this up later */
ewah_start = sb->len;
bitmap = ewah_new();
for (i = 0; i < istate->cache_nr; i++)
if (!(istate->cache[i]->ce_flags & CE_FSMONITOR_VALID))
ewah_set(bitmap, i);
ewah_serialize_strbuf(bitmap, sb);
ewah_free(bitmap);
ewah_serialize_strbuf(istate->fsmonitor_dirty, sb);
ewah_free(istate->fsmonitor_dirty);
istate->fsmonitor_dirty = NULL;
/* fix up size field */
put_be32(&ewah_size, sb->len - ewah_start);

View File

@ -10,7 +10,14 @@ extern struct trace_key trace_fsmonitor;
extern int read_fsmonitor_extension(struct index_state *istate, const void *data, unsigned long sz);
/*
* Write the CE_FSMONITOR_VALID state into the fsmonitor index extension.
* Fill the fsmonitor_dirty ewah bits with their state from the index,
* before it is split during writing.
*/
extern void fill_fsmonitor_bitmap(struct index_state *istate);
/*
* Write the CE_FSMONITOR_VALID state into the fsmonitor index
* extension. Reads from the fsmonitor_dirty ewah in the index.
*/
extern void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate);

View File

@ -2525,6 +2525,9 @@ int write_locked_index(struct index_state *istate, struct lock_file *lock,
int new_shared_index, ret;
struct split_index *si = istate->split_index;
if (istate->fsmonitor_last_update)
fill_fsmonitor_bitmap(istate);
if (!si || alternate_index_output ||
(istate->cache_changed & ~EXTMASK)) {
if (si)

View File

@ -301,4 +301,17 @@ do
done
done
# test that splitting the index dosn't interfere
test_expect_success 'splitting the index results in the same state' '
write_integration_script &&
dirty_repo &&
git update-index --fsmonitor &&
git ls-files -f >expect &&
test-dump-fsmonitor >&2 && echo &&
git update-index --fsmonitor --split-index &&
test-dump-fsmonitor >&2 && echo &&
git ls-files -f >actual &&
test_cmp expect actual
'
test_done