Atomically collect callbacks to be broken

Collect callbacks to be broken in one go, otherwise a file server may
lock out a client while new callbacks tickle in.

With revised multi_Rx, responses get handled early, taking away an argument for
issuing callbacks in small chunks -> crank up chunk size.

Change-Id: I6822256715d1388aa1a44049315813ea08009105
Reviewed-on: http://gerrit.openafs.org/3909
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
This commit is contained in:
Rainer Toebbicke 2010-12-06 15:39:25 +01:00 committed by Jeffrey Altman
parent 2386f5741d
commit 843d705ca6
2 changed files with 27 additions and 16 deletions

View File

@ -799,8 +799,8 @@ BreakCallBack(struct host *xhost, AFSFid * fid, int flag)
{
struct FileEntry *fe;
struct CallBack *cb, *nextcb;
struct cbstruct cba[MAX_CB_HOSTS];
int ncbas;
struct cbstruct cbaDef[MAX_CB_HOSTS], *cba = cbaDef;
unsigned int ncbas, cbaAlloc = MAX_CB_HOSTS;
struct AFSCBFids tf;
int hostindex;
char hoststr[16];
@ -825,8 +825,7 @@ BreakCallBack(struct host *xhost, AFSFid * fid, int flag)
tf.AFSCBFids_len = 1;
tf.AFSCBFids_val = fid;
for (; cb;) {
for (ncbas = 0; cb && ncbas < MAX_CB_HOSTS; cb = nextcb) {
for (ncbas = 0; cb ; cb = nextcb) {
nextcb = itocb(cb->cnext);
if ((cb->hhead != hostindex || flag)
&& (cb->status == CB_BULK || cb->status == CB_NORMAL
@ -843,6 +842,21 @@ BreakCallBack(struct host *xhost, AFSFid * fid, int flag)
} else {
if (!(thishost->hostFlags & HOSTDELETED)) {
h_Hold_r(thishost);
if (ncbas == cbaAlloc) { /* Need more space */
int curLen = cbaAlloc*sizeof(cba[0]);
struct cbstruct *cbaOld = (cba == cbaDef) ? NULL : cba;
/* There are logical contraints elsewhere that the number of hosts
(i.e. h_HTSPERBLOCK*h_MAXHOSTTABLES) remains in the realm of a signed "int".
cbaAlloc is defined unsigned int hence doubling below cannot overflow
*/
cbaAlloc = cbaAlloc<<1; /* double */
cba = realloc(cbaOld, cbaAlloc * sizeof(cba[0]));
if (cbaOld == NULL) { /* realloc wouldn't have copied from cbaDef */
memcpy(cba, cbaDef, curLen);
}
}
cba[ncbas].hp = thishost;
cba[ncbas].thead = cb->thead;
ncbas++;
@ -856,20 +870,16 @@ BreakCallBack(struct host *xhost, AFSFid * fid, int flag)
}
if (ncbas) {
MultiBreakCallBack_r(cba, ncbas, &tf, xhost);
struct cbstruct *cba2;
int num;
/* we need to to all these initializations again because MultiBreakCallBack may block */
fe = FindFE(fid);
if (!fe) {
goto done;
}
cb = itocb(fe->firstcb);
if (!cb || ((fe->ncbs == 1) && (cb->hhead == hostindex) && !flag)) {
/* the most common case is what follows the || */
goto done;
for (cba2 = cba, num = ncbas; ncbas > 0; cba2 += num, ncbas -= num) {
num = (ncbas > MAX_CB_HOSTS) ? MAX_CB_HOSTS : ncbas;
MultiBreakCallBack_r(cba2, num, &tf, xhost);
}
}
}
if (cba != cbaDef) free(cba);
done:
H_UNLOCK;

View File

@ -19,7 +19,8 @@
* thereby swamping the file server. As a result, something like
* 10 or 15 might be a better bet.
*/
#define MAX_CB_HOSTS 10
/* With revised multi_Rx, responses get handled as early as they tickle in, so try big */
#define MAX_CB_HOSTS 1024
/* max time to break a callback, otherwise client is dead or net is hosed */
#define MAXCBT 25