Rename the packing_data lock to obd_lock and upgrade it to a recursive
mutex to make it suitable for current read_lock usages. Additionally
remove the superfluous #ifndef NO_PTHREADS guard around mutex
initialization in prepare_packing_data as the mutex functions
themselves are already protected.
Signed-off-by: Patrick Hogg <phogg@xxxxxxxxxxxx>
Thanks-to: Junio C Hamano <gitster@xxxxxxxxx>
---
builtin/pack-objects.c | 24 ++++++++++--------------
pack-objects.c | 5 +----
pack-objects.h | 21 ++++++++-------------
3 files changed, 19 insertions(+), 31 deletions(-)
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 506061b4c..cfef48217 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -1953,10 +1953,6 @@ static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
return 0;
}
-/* Protect access to object database */
-#define read_lock() packing_data_read_lock(&to_pack)
-#define read_unlock() packing_data_read_unlock(&to_pack)
-
/* Protect delta_cache_size */
static pthread_mutex_t cache_mutex;
#define cache_lock() pthread_mutex_lock(&cache_mutex)
@@ -1992,11 +1988,11 @@ unsigned long oe_get_size_slow(struct packing_data *pack,
unsigned long used, avail, size;
if (e->type_ != OBJ_OFS_DELTA && e->type_ != OBJ_REF_DELTA) {
- read_lock();
+ packing_data_lock(&to_pack);
if (oid_object_info(the_repository, &e->idx.oid, &size) < 0)
die(_("unable to get size of %s"),
oid_to_hex(&e->idx.oid));
- read_unlock();
+ packing_data_unlock(&to_pack);
return size;
}
@@ -2004,7 +2000,7 @@ unsigned long oe_get_size_slow(struct packing_data *pack,
if (!p)
BUG("when e->type is a delta, it must belong to a pack");
- read_lock();
+ packing_data_lock(&to_pack);
w_curs = NULL;
buf = use_pack(p, &w_curs, e->in_pack_offset, &avail);
used = unpack_object_header_buffer(buf, avail, &type, &size);
@@ -2013,7 +2009,7 @@ unsigned long oe_get_size_slow(struct packing_data *pack,
oid_to_hex(&e->idx.oid));
unuse_pack(&w_curs);
- read_unlock();
+ packing_data_unlock(&to_pack);
return size;
}
@@ -2075,9 +2071,9 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
/* Load data if not already done */
if (!trg->data) {
- read_lock();
+ packing_data_lock(&to_pack);
trg->data = read_object_file(&trg_entry->idx.oid, &type, &sz);
- read_unlock();
+ packing_data_unlock(&to_pack);
if (!trg->data)
die(_("object %s cannot be read"),
oid_to_hex(&trg_entry->idx.oid));
@@ -2088,9 +2084,9 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
*mem_usage += sz;
}
if (!src->data) {
- read_lock();
+ packing_data_lock(&to_pack);
src->data = read_object_file(&src_entry->idx.oid, &type, &sz);
- read_unlock();
+ packing_data_unlock(&to_pack);
if (!src->data) {
if (src_entry->preferred_base) {
static int warned = 0;
@@ -2336,9 +2332,9 @@ static void find_deltas(struct object_entry **list, unsigned *list_size,
static void try_to_free_from_threads(size_t size)
{
- read_lock();
+ packing_data_lock(&to_pack);
release_pack_memory(size);
- read_unlock();
+ packing_data_unlock(&to_pack);
}
static try_to_free_t old_try_to_free_routine;
diff --git a/pack-objects.c b/pack-objects.c
index 3554c43ac..a1dc5eb72 100644
--- a/pack-objects.c
+++ b/pack-objects.c
@@ -148,10 +148,7 @@ void prepare_packing_data(struct packing_data *pdata)
1U << OE_SIZE_BITS);
pdata->oe_delta_size_limit = git_env_ulong("GIT_TEST_OE_DELTA_SIZE",
1UL << OE_DELTA_SIZE_BITS);
-#ifndef NO_PTHREADS
- pthread_mutex_init(&pdata->lock, NULL);
- init_recursive_mutex(&pdata->read_lock);
-#endif
+ init_recursive_mutex(&pdata->odb_lock);
}
struct object_entry *packlist_alloc(struct packing_data *pdata,
diff --git a/pack-objects.h b/pack-objects.h
index 0a038e3bc..1667cbad8 100644
--- a/pack-objects.h
+++ b/pack-objects.h
@@ -145,8 +145,11 @@ struct packing_data {
struct packed_git **in_pack_by_idx;
struct packed_git **in_pack;
- pthread_mutex_t lock;
- pthread_mutex_t read_lock;
+ /*
+ * During packing with multiple threads, protect the in-core
+ * object database from concurrent accesses.
+ */
+ pthread_mutex_t odb_lock;
/*
* This list contains entries for bases which we know the other side
@@ -166,22 +169,14 @@ struct packing_data {
void prepare_packing_data(struct packing_data *pdata);
+/* Protect access to object database */
static inline void packing_data_lock(struct packing_data *pdata)
{
- pthread_mutex_lock(&pdata->lock);
+ pthread_mutex_lock(&pdata->odb_lock);
}
static inline void packing_data_unlock(struct packing_data *pdata)
{
- pthread_mutex_unlock(&pdata->lock);
-}
-
-static inline void packing_data_read_lock(struct packing_data *pdata)
-{
- pthread_mutex_lock(&pdata->read_lock);
-}
-static inline void packing_data_read_unlock(struct packing_data *pdata)
-{
- pthread_mutex_unlock(&pdata->read_lock);
+ pthread_mutex_unlock(&pdata->odb_lock);
}
struct object_entry *packlist_alloc(struct packing_data *pdata,
--
2.20.1.windows.1
