hcq/MaxScale
hcq/MaxScale
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Work around debug assertions in binlogrouter

Browse Source 
The binlogrouter uses buffers across worker threads which is no longer OK
in 2.3. The correct solution would be to store data in something other
than a GWBUF (e.g. std::vector) and protect the sharing with a mutex. The
current solution simply works around the assertions by using macros
instead of functions.
This commit is contained in:
Markus Mäkelä 2018-10-04 11:12:03 +03:00
parent e73ecae677
commit 661bdd5b82
No known key found for this signature in database
GPG Key ID: 72D48FCE664F7B19
1 changed files with 25 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
server/modules/routing/binlogrouter/blr_slave.cc
View File

@ -753,8 +753,6 @@ static int blr_slave_query(ROUTER_INSTANCE* router, ROUTER_SLAVE* slave, GWBUF*
*/
static int blr_slave_replay(ROUTER_INSTANCE* router, ROUTER_SLAVE* slave, GWBUF* master)
{
GWBUF* clone;
if (router->master_state == BLRM_UNCONFIGURED)
{
return blr_slave_send_ok(router, slave);
@ -765,8 +763,32 @@ static int blr_slave_replay(ROUTER_INSTANCE* router, ROUTER_SLAVE* slave, GWBUF*
return 0;
}
if ((clone = gwbuf_clone(master)) != NULL)
/**
* Note: The following manipulation of the buffers bypasses the thread-local checks that are present
* to prevent cross-thread usage of buffers. As the binlogrouter doesn't care about that, we have to
* avoid the checks in order to prevent debug assertions. This is definitely not something that should
* be done and a better solution would be to just store the data inside a vector and protect access with
* a lock.
*/
size_t len = 0;
for (GWBUF* b = master; b; b = b->next)
{
len += GWBUF_LENGTH(b);
}
GWBUF* clone = gwbuf_alloc(len);
if (clone)
{
uint8_t* data = GWBUF_DATA(clone);
for (GWBUF* b = master; b; b = b->next)
{
memcpy(data, GWBUF_DATA(b), GWBUF_LENGTH(b));
data += GWBUF_LENGTH(b);
}
return MXS_SESSION_ROUTE_REPLY(slave->dcb->session, clone);
}
else