readwritesplit.c:routeQuery if target is master but it is found out when get_dcb returns that master DCB has changed, routeQuery fails and logs to trace that master changed.

This commit is contained in:
VilhoRaatikka
2014-10-20 10:40:32 +03:00
parent 319dd4b3e6
commit ebd92c8741

View File

@ -849,7 +849,7 @@ static void* newSession(
free(client_rses); free(client_rses);
client_rses = NULL; client_rses = NULL;
goto return_rses; goto return_rses;
} }
/** Copy backend pointers to router session. */ /** Copy backend pointers to router session. */
client_rses->rses_master_ref = master_ref; client_rses->rses_master_ref = master_ref;
/* assert with master_host */ /* assert with master_host */
@ -1065,9 +1065,12 @@ static bool get_dcb(
/** get root master from available servers */ /** get root master from available servers */
master_bref = get_root_master_bref(rses); master_bref = get_root_master_bref(rses);
#if defined(SS_DEBUG) #if defined(SS_DEBUG)
master_host = get_root_master(backend_ref, rses->rses_nbackends); master_host = get_root_master(backend_ref, rses->rses_nbackends);
ss_dassert(master_bref->bref_backend == master_host); if (master_bref->bref_backend != master_host)
{
LOGIF(LT, (skygw_log_write(LOGFILE_TRACE,
"Master has changed.")));
}
#endif #endif
if (name != NULL) /*< Choose backend by name from a hint */ if (name != NULL) /*< Choose backend by name from a hint */
{ {
@ -1714,6 +1717,7 @@ static int routeQuery(
querybuf = gwbuf_make_contiguous(querybuf); querybuf = gwbuf_make_contiguous(querybuf);
} }
/** Read stored master DCB pointer */
master_dcb = router_cli_ses->rses_master_ref->bref_dcb; master_dcb = router_cli_ses->rses_master_ref->bref_dcb;
CHK_DCB(master_dcb); CHK_DCB(master_dcb);
@ -2000,30 +2004,43 @@ static int routeQuery(
if (!succp && TARGET_IS_MASTER(route_target)) if (!succp && TARGET_IS_MASTER(route_target))
{ {
if (master_dcb == NULL) DCB* curr_master_dcb;
succp = get_dcb(&curr_master_dcb,
router_cli_ses,
BE_MASTER,
NULL,
MAX_RLAG_UNDEFINED);
if (succp && (master_dcb == NULL || master_dcb == curr_master_dcb))
{ {
succp = get_dcb(&master_dcb, atomic_add(&inst->stats.n_master, 1);
router_cli_ses, target_dcb = master_dcb;
BE_MASTER, }
NULL, else
MAX_RLAG_UNDEFINED); {
if (!succp) if (succp && master_dcb != curr_master_dcb)
{ {
LOGIF(LT, (skygw_log_write(LOGFILE_TRACE, LOGIF(LT, (skygw_log_write(LOGFILE_TRACE,
"Was supposed to " "Was supposed to "
"route to master " "route to master "
"but couldn't find " "but master has "
"master in a " "changed.")));
"suitable state "
"failed.")));
} }
else
{
LOGIF(LT, (skygw_log_write(LOGFILE_TRACE,
"Was supposed to "
"route to master "
"but couldn't find "
"master in a "
"suitable state "
"failed.")));
}
succp = false;
ret = 0;
} }
else
{
succp = true;
}
atomic_add(&inst->stats.n_master, 1);
target_dcb = master_dcb;
} }
if (succp) /*< Have DCB of the target backend */ if (succp) /*< Have DCB of the target backend */
@ -2595,7 +2612,7 @@ static bool select_connect_backend_servers(
} }
/* get the root Master */ /* get the root Master */
master_host = get_root_master(backend_ref, router_nservers); master_host = get_root_master(backend_ref, router_nservers);
/** Master is already chosen and connected. This is slave failure case */ /** Master is already chosen and connected. This is slave failure case */
if (*p_master_ref != NULL && if (*p_master_ref != NULL &&
@ -2610,11 +2627,16 @@ static bool select_connect_backend_servers(
master_found = true; master_found = true;
master_connected = true; master_connected = true;
/* assert with master_host */
/**
* Ensure that *p_master_ref and master_host point to same backend
* and it has a master role.
*/
ss_dassert(master_host && ss_dassert(master_host &&
((*p_master_ref)->bref_backend->backend_server == ((*p_master_ref)->bref_backend->backend_server ==
master_host->backend_server) && master_host->backend_server) &&
SERVER_MASTER); (master_host->backend_server->status &
(SERVER_MASTER|SERVER_MAINT)) == SERVER_MASTER);
} }
/** New session or master failure case */ /** New session or master failure case */
else else