diff options
Diffstat (limited to 'contrib/pgrowlocks/pgrowlocks.c')
| -rw-r--r-- | contrib/pgrowlocks/pgrowlocks.c | 178 |
1 files changed, 126 insertions, 52 deletions
diff --git a/contrib/pgrowlocks/pgrowlocks.c b/contrib/pgrowlocks/pgrowlocks.c index 20beed2a300..43ada57352d 100644 --- a/contrib/pgrowlocks/pgrowlocks.c +++ b/contrib/pgrowlocks/pgrowlocks.c @@ -59,6 +59,13 @@ typedef struct int ncolumns; } MyData; +#define Atnum_tid 0 +#define Atnum_xmax 1 +#define Atnum_ismulti 2 +#define Atnum_xids 3 +#define Atnum_modes 4 +#define Atnum_pids 5 + Datum pgrowlocks(PG_FUNCTION_ARGS) { @@ -117,79 +124,146 @@ pgrowlocks(PG_FUNCTION_ARGS) /* scan the relation */ while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL) { + HTSU_Result htsu; + TransactionId xmax; + uint16 infomask; + /* must hold a buffer lock to call HeapTupleSatisfiesUpdate */ LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE); - if (HeapTupleSatisfiesUpdate(tuple->t_data, - GetCurrentCommandId(false), - scan->rs_cbuf) == HeapTupleBeingUpdated) + htsu = HeapTupleSatisfiesUpdate(tuple->t_data, + GetCurrentCommandId(false), + scan->rs_cbuf); + xmax = HeapTupleHeaderGetRawXmax(tuple->t_data); + infomask = tuple->t_data->t_infomask; + + /* + * a tuple is locked if HTSU returns BeingUpdated, and if it returns + * MayBeUpdated but the Xmax is valid and pointing at us. + */ + if (htsu == HeapTupleBeingUpdated || + (htsu == HeapTupleMayBeUpdated && + !(infomask & HEAP_XMAX_INVALID) && + !(infomask & HEAP_XMAX_IS_MULTI) && + (xmax == GetCurrentTransactionIdIfAny()))) { - char **values; - int i; values = (char **) palloc(mydata->ncolumns * sizeof(char *)); - i = 0; - values[i++] = (char *) DirectFunctionCall1(tidout, PointerGetDatum(&tuple->t_self)); + values[Atnum_tid] = (char *) DirectFunctionCall1(tidout, + PointerGetDatum(&tuple->t_self)); - if (tuple->t_data->t_infomask & HEAP_XMAX_SHARED_LOCK) - values[i++] = pstrdup("Shared"); - else - values[i++] = pstrdup("Exclusive"); - values[i] = palloc(NCHARS * sizeof(char)); - snprintf(values[i++], NCHARS, "%d", HeapTupleHeaderGetXmax(tuple->t_data)); - if (tuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI) + values[Atnum_xmax] = palloc(NCHARS * sizeof(char)); + snprintf(values[Atnum_xmax], NCHARS, "%d", xmax); + if (infomask & HEAP_XMAX_IS_MULTI) { - TransactionId *xids; - int nxids; - int j; - int isValidXid = 0; /* any valid xid ever exists? */ - - values[i++] = pstrdup("true"); - nxids = GetMultiXactIdMembers(HeapTupleHeaderGetXmax(tuple->t_data), &xids); - if (nxids == -1) + MultiXactMember *members; + int nmembers; + bool first = true; + bool allow_old; + + values[Atnum_ismulti] = pstrdup("true"); + + allow_old = !(infomask & HEAP_LOCK_MASK) && + (infomask & HEAP_XMAX_LOCK_ONLY); + nmembers = GetMultiXactIdMembers(xmax, &members, allow_old); + if (nmembers == -1) { - elog(ERROR, "GetMultiXactIdMembers returns error"); + values[Atnum_xids] = "{0}"; + values[Atnum_modes] = "{transient upgrade status}"; + values[Atnum_pids] = "{0}"; } + else + { + int j; - values[i] = palloc(NCHARS * nxids); - values[i + 1] = palloc(NCHARS * nxids); - strcpy(values[i], "{"); - strcpy(values[i + 1], "{"); + values[Atnum_xids] = palloc(NCHARS * nmembers); + values[Atnum_modes] = palloc(NCHARS * nmembers); + values[Atnum_pids] = palloc(NCHARS * nmembers); - for (j = 0; j < nxids; j++) - { - char buf[NCHARS]; + strcpy(values[Atnum_xids], "{"); + strcpy(values[Atnum_modes], "{"); + strcpy(values[Atnum_pids], "{"); - if (TransactionIdIsInProgress(xids[j])) + for (j = 0; j < nmembers; j++) { - if (isValidXid) + char buf[NCHARS]; + + if (!first) { - strcat(values[i], ","); - strcat(values[i + 1], ","); + strcat(values[Atnum_xids], ","); + strcat(values[Atnum_modes], ","); + strcat(values[Atnum_pids], ","); } - snprintf(buf, NCHARS, "%d", xids[j]); - strcat(values[i], buf); - snprintf(buf, NCHARS, "%d", BackendXidGetPid(xids[j])); - strcat(values[i + 1], buf); + snprintf(buf, NCHARS, "%d", members[j].xid); + strcat(values[Atnum_xids], buf); + switch (members[j].status) + { + case MultiXactStatusUpdate: + snprintf(buf, NCHARS, "Update"); + break; + case MultiXactStatusNoKeyUpdate: + snprintf(buf, NCHARS, "No Key Update"); + break; + case MultiXactStatusForUpdate: + snprintf(buf, NCHARS, "For Update"); + break; + case MultiXactStatusForNoKeyUpdate: + snprintf(buf, NCHARS, "For No Key Update"); + break; + case MultiXactStatusForShare: + snprintf(buf, NCHARS, "Share"); + break; + case MultiXactStatusForKeyShare: + snprintf(buf, NCHARS, "Key Share"); + break; + } + strcat(values[Atnum_modes], buf); + snprintf(buf, NCHARS, "%d", + BackendXidGetPid(members[j].xid)); + strcat(values[Atnum_pids], buf); - isValidXid = 1; + first = false; } - } - strcat(values[i], "}"); - strcat(values[i + 1], "}"); - i++; + strcat(values[Atnum_xids], "}"); + strcat(values[Atnum_modes], "}"); + strcat(values[Atnum_pids], "}"); + } } else { - values[i++] = pstrdup("false"); - values[i] = palloc(NCHARS * sizeof(char)); - snprintf(values[i++], NCHARS, "{%d}", HeapTupleHeaderGetXmax(tuple->t_data)); + values[Atnum_ismulti] = pstrdup("false"); + + values[Atnum_xids] = palloc(NCHARS * sizeof(char)); + snprintf(values[Atnum_xids], NCHARS, "{%d}", xmax); + + values[Atnum_modes] = palloc(NCHARS); + if (infomask & HEAP_XMAX_LOCK_ONLY) + { + if (HEAP_XMAX_IS_SHR_LOCKED(infomask)) + snprintf(values[Atnum_modes], NCHARS, "{For Share}"); + else if (HEAP_XMAX_IS_KEYSHR_LOCKED(infomask)) + snprintf(values[Atnum_modes], NCHARS, "{For Key Share}"); + else if (HEAP_XMAX_IS_EXCL_LOCKED(infomask)) + snprintf(values[Atnum_modes], NCHARS, "{For Update}"); + else + /* neither keyshare nor exclusive bit it set */ + snprintf(values[Atnum_modes], NCHARS, + "{transient upgrade status}"); + } + else + { + if (tuple->t_data->t_infomask2 & HEAP_KEYS_UPDATED) + snprintf(values[Atnum_modes], NCHARS, "{Key Update}"); + else + snprintf(values[Atnum_modes], NCHARS, "{Update}"); + } - values[i] = palloc(NCHARS * sizeof(char)); - snprintf(values[i++], NCHARS, "{%d}", BackendXidGetPid(HeapTupleHeaderGetXmax(tuple->t_data))); + values[Atnum_pids] = palloc(NCHARS * sizeof(char)); + snprintf(values[Atnum_pids], NCHARS, "{%d}", + BackendXidGetPid(xmax)); } LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK); @@ -200,10 +274,10 @@ pgrowlocks(PG_FUNCTION_ARGS) /* make the tuple into a datum */ result = HeapTupleGetDatum(tuple); - /* Clean up */ - for (i = 0; i < mydata->ncolumns; i++) - pfree(values[i]); - pfree(values); + /* + * no need to pfree what we allocated; it's on a short-lived memory + * context anyway + */ SRF_RETURN_NEXT(funcctx, result); } |