diff options
| -rw-r--r-- | src/backend/utils/activity/pgstat.c | 5 | ||||
| -rw-r--r-- | src/backend/utils/activity/pgstat_shmem.c | 10 | ||||
| -rw-r--r-- | src/include/utils/pgstat_internal.h | 17 |
3 files changed, 19 insertions, 13 deletions
diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index f8e91484e36..73c2ced3f4e 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -932,7 +932,7 @@ pgstat_clear_snapshot(void) void * pgstat_fetch_entry(PgStat_Kind kind, Oid dboid, uint64 objid) { - PgStat_HashKey key; + PgStat_HashKey key = {0}; PgStat_EntryRef *entry_ref; void *stats_data; const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind); @@ -943,9 +943,6 @@ pgstat_fetch_entry(PgStat_Kind kind, Oid dboid, uint64 objid) pgstat_prep_snapshot(); - /* clear padding */ - memset(&key, 0, sizeof(struct PgStat_HashKey)); - key.kind = kind; key.dboid = dboid; key.objid = objid; diff --git a/src/backend/utils/activity/pgstat_shmem.c b/src/backend/utils/activity/pgstat_shmem.c index 9dc3212f7dd..ca36fd247f6 100644 --- a/src/backend/utils/activity/pgstat_shmem.c +++ b/src/backend/utils/activity/pgstat_shmem.c @@ -456,14 +456,11 @@ PgStat_EntryRef * pgstat_get_entry_ref(PgStat_Kind kind, Oid dboid, uint64 objid, bool create, bool *created_entry) { - PgStat_HashKey key; + PgStat_HashKey key = {0}; PgStatShared_HashEntry *shhashent; PgStatShared_Common *shheader = NULL; PgStat_EntryRef *entry_ref; - /* clear padding */ - memset(&key, 0, sizeof(struct PgStat_HashKey)); - key.kind = kind; key.dboid = dboid; key.objid = objid; @@ -988,13 +985,10 @@ pgstat_drop_database_and_contents(Oid dboid) bool pgstat_drop_entry(PgStat_Kind kind, Oid dboid, uint64 objid) { - PgStat_HashKey key; + PgStat_HashKey key = {0}; PgStatShared_HashEntry *shent; bool freed = true; - /* clear padding */ - memset(&key, 0, sizeof(struct PgStat_HashKey)); - key.kind = kind; key.dboid = dboid; key.objid = objid; diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h index 6cf00008f63..bf75ebcef31 100644 --- a/src/include/utils/pgstat_internal.h +++ b/src/include/utils/pgstat_internal.h @@ -48,7 +48,13 @@ * PgStatShared_Common as the first element. */ -/* struct for shared statistics hash entry key. */ +/* + * Struct for shared statistics hash entry key. + * + * NB: We assume that this struct contains no padding. Also, 8 bytes + * allocated for the object ID are good enough to ensure the uniqueness + * of the hash key, hence the addition of new fields is not recommended. + */ typedef struct PgStat_HashKey { PgStat_Kind kind; /* statistics entry kind */ @@ -58,6 +64,15 @@ typedef struct PgStat_HashKey } PgStat_HashKey; /* + * PgStat_HashKey should not have any padding. Checking that the structure + * size matches with the sum of each field is a check simple enough to + * enforce this policy. + */ +StaticAssertDecl((sizeof(PgStat_Kind) + sizeof(uint64) + sizeof(Oid)) == + sizeof(PgStat_HashKey), + "PgStat_HashKey should have no padding"); + +/* * Shared statistics hash entry. Doesn't itself contain any stats, but points * to them (with ->body). That allows the stats entries themselves to be of * variable size. |