glusterfs.git/xlators/cluster/ec, branch v3.9rc0

cluster/ec: Use locks for opendir

2016-08-25T13:48:33+00:00

Problem:
In some cases we see that readdir keeps winding to the brick that doesn't have
any blocked locks i.e. first brick. This is leading to the client assuming that
there are no blocking locks on the inode so it won't give away the lock. Other
clients end up blocked on the lock as if the command hung.

Fix:
Proper way to fix this issue is to use infra present in
http://review.gluster.org/14736 This is a stop gap fix where we start taking
inodelks in opendir which goes to all the bricks, this will detect if there is
any contention.

BUG: 1346719
Change-Id: I91109107a26f6535b945ac476338e9f21dc31eb9
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/15309
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Ashish Pandey

cluster/ec: Do multi-threaded self-heal

2016-08-24T22:24:22+00:00

BUG: 1368451
Change-Id: I5d6b91d714ad6906dc478a401e614115c89a8fbb
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/15083
Smoke: Gluster Build System 
Reviewed-by: Ashish Pandey 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

cluster/afr: Prevent split-brain when bricks are brought off and on in cyclic order

2016-08-22T09:38:36+00:00

When the bricks are brought offline and then online in cyclic
order while writes are in progress on a file, thanks to inode
refresh in write txns, AFR will mostly fail the write attempt
when the only good copy is offline. However, there is still a
remote possibility that the file will run into split-brain if
the brick that has the lone good copy goes offline *after* the
inode refresh but *before* the write txn completes (I call it
in-flight split-brain in the patch for ease of reference),
requiring intervention from admin to resolve the split-brain
before the IO can resume normally on the file. To get around this,
the patch does the following things:
i) retains the dirty xattrs on the file
ii) avoids marking the last of the good copies as bad (or accused)
    in case it is the one to go down during the course of a write.
iii) fails that particular write with the appropriate errno.

This way, we still have one good copy left despite the split-brain situation
which when it is back online, will be chosen as source to do the heal.

Change-Id: I9ca634b026ac830b172bac076437cc3bf1ae7d8a
BUG: 1363721
Signed-off-by: Krutika Dhananjay 
Reviewed-on: http://review.gluster.org/15080
Tested-by: Pranith Kumar Karampuri 
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Ravishankar N 
Reviewed-by: Oleksandr Natalenko 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Pranith Kumar Karampuri

libglusterfs: move alloca0 definition to common-utils

2016-08-12T08:53:23+00:00

...and remove their definitons from EC and AFR.
Also `s/alloca+memset0/alloca0` wherever it is used.

Change-Id: I3b71e596d12a7d8900f5d761af6b98305c8874d5
BUG: 1366226
Signed-off-by: Ravishankar N 
Reviewed-on: http://review.gluster.org/15147
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Pranith Kumar Karampuri 
CentOS-regression: Gluster Build System

cluster/ec: Handle absence of keys in some callback dict

2016-07-26T06:07:03+00:00

Problem: This issue arises when we do a rolling update
from 3.7.5 to 3.7.9.
For 4+2 volume running 3.7.5, if we update 2 nodes
and after heal completion  kill 2 older nodes, this
problem can be seen. After update and killing of
bricks, 2 nodes will return inodelk count key in dict
while other 2 nodes will not have inodelk count in dict.
This is also true for get-link-count.
During dictionary match , ec_dict_compare, this will
lead to mismatch of answers and the file operation
on mount point will fail with IO error.

Solution:
Don't match inode, entry and link count keys while
comparing two dictionaries. However, while combining the
data in ec_dict_combine, go through all the dictionaries
and select the maximum values received in different dicts
for these keys.

Change-Id: I33546e3619fe8f909286ee48fb0df2009cd3d22f
BUG: 1347686
Signed-off-by: Ashish Pandey 
Reviewed-on: http://review.gluster.org/14761
Reviewed-by: Xavier Hernandez 
Smoke: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System

core: add a basis function to reduce verbose code

2016-07-18T11:59:05+00:00

Change-Id: Icebe1b865edb317685e93f3ef11d98fd9b2c2e9a
BUG: 1357226
Signed-off-by: Zhou Zhengping 
Reviewed-on: http://review.gluster.org/14936
Reviewed-by: Niels de Vos 
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System

cluster/ec: Unlock stale locks when inodelk/entrylk/lk fails

2016-06-14T10:48:54+00:00

Thanks to Rafi for hinting a while back that this kind of
problem he saw once. I didn't think the theory was valid.
Could have caught it earlier if I had tested his theory.

Change-Id: Iac6ffcdba2950aa6f8cf94f8994adeed6e6a9c9b
BUG: 1344836
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/14703
Reviewed-by: Xavier Hernandez 
Smoke: Gluster Build System 
Tested-by: mohammed rafi  kc 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

cluster/ec: Fix race in timer cancellation

2016-06-14T01:03:18+00:00

A race in timer cancellation for delayed unlock could cause a crash
if the cancelling thread fails to cancel the timer because it has
already been fired but not executed, and the callback is scheduled
out of the CPU, delaying it until the thread has released important
resources needed by the callback.

This patch improves the handling of this case to make it robust.

Change-Id: I5c8a8c6610c5136f71b938aa78b5878ba05238d4
BUG: 1345855
Signed-off-by: Xavier Hernandez 
Reviewed-on: http://review.gluster.org/14712
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri

cluster/ec: Fix invalid __fd_unref() call

2016-06-13T12:14:38+00:00

__fd_unref() doesn't do any cleanup, so it cannot be called to release
fd references, specially if it's the last reference.

The code has been changed to avoid a call to this function.

In the previous version we always tried to keep the newest fd in the
ec_lock_t structure. However this is not necessary. We'll always keep
one reference to an open file on the same inode. It's irrelevant if
the reference is new or old.

The function __fd_unref() has also been removed from fd.h to avoid being
used in the future since it's useless as it's defined now.

Change-Id: Ia728777fc8e464758d5ea4d3bf020f0603919039
BUG: 1344396
Signed-off-by: Xavier Hernandez 
Reviewed-on: http://review.gluster.org/14683
NetBSD-regression: NetBSD Build System 
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Ashish Pandey 
Reviewed-by: Jeff Darcy

cluster/ec: Pass xdata to dht in case of error

2016-06-10T09:14:37+00:00

Problem: In case of mkdir failure, dht expects
error information so that it can act accordingly.
Aftre adding bricks and re balance, layout gets
changed. Fop "mkdir" with old layout returns EIO.
EC gets this error in xdata but does not pass it
back to dht. In this case dht will not be able to
take corrective action.

Solution: Return xdata back to dht

Change-Id: I24def8038e6880607689b7b046dc6428f564c6ab
BUG: 1344277
Signed-off-by: Ashish Pandey 
Reviewed-on: http://review.gluster.org/14679
Reviewed-by: Pranith Kumar Karampuri 
Reviewed-by: Xavier Hernandez 
Tested-by: Atin Mukherjee 
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System