Tags: patch
Hi,
The attached patch from Wes Chow <[EMAIL PROTECTED]> fixes the various
places where afs_cacheBlocks having a large value will overflow an int32
and cause the multiplication to be incorrect. Instead of basically doing:
(95*afs_cacheBlocks) / 100
all over the place, we instead do
95 * (afs_cacheBlocks/100)
Obviously, this will cause a loss of precision; however, the worst it
could possibly be is 99k (if using a value like 80000099 in your
cacheinfo). This should be an acceptable loss, I would imagine.
The patch also fixes one place where afs_cacheFiles does basically the
same thing (in afs.h). It is included in the patch for completeness; if
you disagree w/ it, I can understand. I'm not sure of any real world
scenarios where that would overflow (it's -5*afs_cacheFiles, and
afs_cacheFiles default in debian only goes as high as 80000 aiui). It
also causes a loss of precision.
The patch is attached.
diff -r -u openafs.orig/openafs-1.4.0/src/afs/afs_dcache.c openafs.new/openafs-1.4.0/src/afs/afs_dcache.c
--- openafs.orig/openafs-1.4.0/src/afs/afs_dcache.c 2005-08-04 16:45:14.000000000 -0400
+++ openafs.new/openafs-1.4.0/src/afs/afs_dcache.c 2006-03-30 15:54:14.308241504 -0500
@@ -231,8 +231,8 @@
osi_GetuTime(&CTD_stats.CTD_afterSleep);
afs_TruncateDaemonRunning = 1;
while (1) {
- cb_lowat = ((CM_DCACHESPACEFREEPCT - CM_DCACHEEXTRAPCT)
- * afs_cacheBlocks) / 100;
+ cb_lowat = (CM_DCACHESPACEFREEPCT - CM_DCACHEEXTRAPCT)
+ * (afs_cacheBlocks / 100);
MObtainWriteLock(&afs_xdcache, 266);
if (afs_CacheTooFull) {
int space_needed, slots_needed;
@@ -777,7 +777,7 @@
if (afs_WaitForCacheDrain) {
if (afs_blocksUsed <=
- (CM_CACHESIZEDRAINEDPCT * afs_cacheBlocks) / 100) {
+ CM_CACHESIZEDRAINEDPCT * (afs_cacheBlocks / 100)) {
afs_WaitForCacheDrain = 0;
afs_osi_Wakeup(&afs_WaitForCacheDrain);
}
@@ -810,7 +810,7 @@
if (afs_WaitForCacheDrain) {
if ((afs_blocksUsed - afs_blocksDiscarded) <=
- (CM_CACHESIZEDRAINEDPCT * afs_cacheBlocks) / 100) {
+ CM_CACHESIZEDRAINEDPCT * (afs_cacheBlocks / 100)) {
afs_WaitForCacheDrain = 0;
afs_osi_Wakeup(&afs_WaitForCacheDrain);
}
@@ -860,7 +860,7 @@
if (afs_WaitForCacheDrain) {
if ((afs_blocksUsed - afs_blocksDiscarded) <=
- (CM_CACHESIZEDRAINEDPCT * afs_cacheBlocks) / 100) {
+ CM_CACHESIZEDRAINEDPCT * (afs_cacheBlocks / 100)) {
afs_WaitForCacheDrain = 0;
afs_osi_Wakeup(&afs_WaitForCacheDrain);
}
@@ -943,7 +943,7 @@
while (afs_blocksDiscarded
&& (afs_blocksUsed >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100)) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100))) {
afs_FreeDiscardedDCache();
}
return 0;
@@ -1967,7 +1967,7 @@
/* Sleep here when cache needs to be drained. */
if (setLocks && !slowPass
&& (afs_blocksUsed >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100)) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100))) {
/* Make sure truncate daemon is running */
afs_MaybeWakeupTruncateDaemon();
ObtainWriteLock(&tdc->tlock, 614);
@@ -1976,7 +1976,7 @@
ReleaseWriteLock(&tdc->lock);
ReleaseReadLock(&avc->lock);
while ((afs_blocksUsed - afs_blocksDiscarded) >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
afs_WaitForCacheDrain = 1;
afs_osi_Sleep(&afs_WaitForCacheDrain);
}
diff -r -u openafs.orig/openafs-1.4.0/src/afs/afs.h openafs.new/openafs-1.4.0/src/afs/afs.h
--- openafs.orig/openafs-1.4.0/src/afs/afs.h 2005-07-11 15:29:55.000000000 -0400
+++ openafs.new/openafs-1.4.0/src/afs/afs.h 2006-03-30 15:54:14.309241352 -0500
@@ -1114,9 +1114,9 @@
#define afs_CacheIsTooFull() \
(afs_blocksUsed - afs_blocksDiscarded > \
- (CM_DCACHECOUNTFREEPCT*afs_cacheBlocks)/100 || \
+ CM_DCACHECOUNTFREEPCT*(afs_cacheBlocks/100) || \
afs_freeDCCount - afs_discardDCCount < \
- ((100-CM_DCACHECOUNTFREEPCT)*afs_cacheFiles)/100)
+ (100-CM_DCACHECOUNTFREEPCT)*(afs_cacheFiles/100))
/* Handy max length of a numeric string. */
#define CVBS 12 /* max afs_int32 is 2^32 ~ 4*10^9, +1 for NULL, +luck */
diff -r -u openafs.orig/openafs-1.4.0/src/afs/SOLARIS/osi_vnodeops.c openafs.new/openafs-1.4.0/src/afs/SOLARIS/osi_vnodeops.c
--- openafs.orig/openafs-1.4.0/src/afs/SOLARIS/osi_vnodeops.c 2005-10-12 02:06:47.000000000 -0400
+++ openafs.new/openafs-1.4.0/src/afs/SOLARIS/osi_vnodeops.c 2006-03-30 15:54:14.311241048 -0500
@@ -762,9 +762,9 @@
*/
afs_MaybeWakeupTruncateDaemon();
while ((arw == UIO_WRITE)
- && (afs_blocksUsed > (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100)) {
+ && (afs_blocksUsed > CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100))) {
if (afs_blocksUsed - afs_blocksDiscarded >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
afs_WaitForCacheDrain = 1;
afs_osi_Sleep(&afs_WaitForCacheDrain);
}
diff -r -u openafs.orig/openafs-1.4.0/src/afs/VNOPS/afs_vnop_write.c openafs.new/openafs-1.4.0/src/afs/VNOPS/afs_vnop_write.c
--- openafs.orig/openafs-1.4.0/src/afs/VNOPS/afs_vnop_write.c 2005-10-02 22:55:33.000000000 -0400
+++ openafs.new/openafs-1.4.0/src/afs/VNOPS/afs_vnop_write.c 2006-03-30 15:54:14.312240896 -0500
@@ -198,7 +198,7 @@
if (tdc)
ObtainWriteLock(&tdc->lock, 653);
} else if (afs_blocksUsed >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
tdc = afs_FindDCache(avc, filePos);
if (tdc) {
ObtainWriteLock(&tdc->lock, 654);
@@ -212,10 +212,10 @@
if (!tdc) {
afs_MaybeWakeupTruncateDaemon();
while (afs_blocksUsed >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
ReleaseWriteLock(&avc->lock);
if (afs_blocksUsed - afs_blocksDiscarded >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
afs_WaitForCacheDrain = 1;
afs_osi_Sleep(&afs_WaitForCacheDrain);
}
@@ -442,7 +442,7 @@
if (tdc)
ObtainWriteLock(&tdc->lock, 657);
} else if (afs_blocksUsed >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
tdc = afs_FindDCache(avc, filePos);
if (tdc) {
ObtainWriteLock(&tdc->lock, 658);
@@ -456,10 +456,10 @@
if (!tdc) {
afs_MaybeWakeupTruncateDaemon();
while (afs_blocksUsed >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
ReleaseWriteLock(&avc->lock);
if (afs_blocksUsed - afs_blocksDiscarded >
- (CM_WAITFORDRAINPCT * afs_cacheBlocks) / 100) {
+ CM_WAITFORDRAINPCT * (afs_cacheBlocks / 100)) {
afs_WaitForCacheDrain = 1;
afs_osi_Sleep(&afs_WaitForCacheDrain);
}
