pack-objects: merge read_lock and lock in packing_data struct

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@novamoon.net>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Patrick Hogg
2019-01-24 19:22:05 -05:00
committed by Junio C Hamano
parent 459307b139
commit edb673cf10
3 changed files with 19 additions and 31 deletions

View File

@ -1953,10 +1953,6 @@ static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
return 0; 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 */ /* Protect delta_cache_size */
static pthread_mutex_t cache_mutex; static pthread_mutex_t cache_mutex;
#define cache_lock() pthread_mutex_lock(&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; unsigned long used, avail, size;
if (e->type_ != OBJ_OFS_DELTA && e->type_ != OBJ_REF_DELTA) { 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) if (oid_object_info(the_repository, &e->idx.oid, &size) < 0)
die(_("unable to get size of %s"), die(_("unable to get size of %s"),
oid_to_hex(&e->idx.oid)); oid_to_hex(&e->idx.oid));
read_unlock(); packing_data_unlock(&to_pack);
return size; return size;
} }
@ -2004,7 +2000,7 @@ unsigned long oe_get_size_slow(struct packing_data *pack,
if (!p) if (!p)
BUG("when e->type is a delta, it must belong to a pack"); BUG("when e->type is a delta, it must belong to a pack");
read_lock(); packing_data_lock(&to_pack);
w_curs = NULL; w_curs = NULL;
buf = use_pack(p, &w_curs, e->in_pack_offset, &avail); buf = use_pack(p, &w_curs, e->in_pack_offset, &avail);
used = unpack_object_header_buffer(buf, avail, &type, &size); 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)); oid_to_hex(&e->idx.oid));
unuse_pack(&w_curs); unuse_pack(&w_curs);
read_unlock(); packing_data_unlock(&to_pack);
return size; return size;
} }
@ -2075,9 +2071,9 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
/* Load data if not already done */ /* Load data if not already done */
if (!trg->data) { if (!trg->data) {
read_lock(); packing_data_lock(&to_pack);
trg->data = read_object_file(&trg_entry->idx.oid, &type, &sz); trg->data = read_object_file(&trg_entry->idx.oid, &type, &sz);
read_unlock(); packing_data_unlock(&to_pack);
if (!trg->data) if (!trg->data)
die(_("object %s cannot be read"), die(_("object %s cannot be read"),
oid_to_hex(&trg_entry->idx.oid)); oid_to_hex(&trg_entry->idx.oid));
@ -2088,9 +2084,9 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
*mem_usage += sz; *mem_usage += sz;
} }
if (!src->data) { if (!src->data) {
read_lock(); packing_data_lock(&to_pack);
src->data = read_object_file(&src_entry->idx.oid, &type, &sz); src->data = read_object_file(&src_entry->idx.oid, &type, &sz);
read_unlock(); packing_data_unlock(&to_pack);
if (!src->data) { if (!src->data) {
if (src_entry->preferred_base) { if (src_entry->preferred_base) {
static int warned = 0; 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) static void try_to_free_from_threads(size_t size)
{ {
read_lock(); packing_data_lock(&to_pack);
release_pack_memory(size); release_pack_memory(size);
read_unlock(); packing_data_unlock(&to_pack);
} }
static try_to_free_t old_try_to_free_routine; static try_to_free_t old_try_to_free_routine;

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@ -148,10 +148,7 @@ void prepare_packing_data(struct packing_data *pdata)
1U << OE_SIZE_BITS); 1U << OE_SIZE_BITS);
pdata->oe_delta_size_limit = git_env_ulong("GIT_TEST_OE_DELTA_SIZE", pdata->oe_delta_size_limit = git_env_ulong("GIT_TEST_OE_DELTA_SIZE",
1UL << OE_DELTA_SIZE_BITS); 1UL << OE_DELTA_SIZE_BITS);
#ifndef NO_PTHREADS init_recursive_mutex(&pdata->odb_lock);
pthread_mutex_init(&pdata->lock, NULL);
init_recursive_mutex(&pdata->read_lock);
#endif
} }
struct object_entry *packlist_alloc(struct packing_data *pdata, struct object_entry *packlist_alloc(struct packing_data *pdata,

View File

@ -145,8 +145,11 @@ struct packing_data {
struct packed_git **in_pack_by_idx; struct packed_git **in_pack_by_idx;
struct packed_git **in_pack; 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 * 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); void prepare_packing_data(struct packing_data *pdata);
/* Protect access to object database */
static inline void packing_data_lock(struct packing_data *pdata) 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) static inline void packing_data_unlock(struct packing_data *pdata)
{ {
pthread_mutex_unlock(&pdata->lock); pthread_mutex_unlock(&pdata->odb_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);
} }
struct object_entry *packlist_alloc(struct packing_data *pdata, struct object_entry *packlist_alloc(struct packing_data *pdata,