Currently its passed in dht_blocking_inode(entry)lk, which would be a
global value for all the locks passed in the argument. This would
be a limitation for cases where we want to ignore failures on only few
locks and fail for others.

Change-Id: I02cfbcaafb593ad8140c0e5af725c866b630fb6b
BUG: 1543279
Signed-off-by: Raghavendra G <rgowdapp@redhat.com>

For more details on this issue see
https://github.com/gluster/glusterfs/issues/308

Solution:
This is a restrictive solution where a file will not be migrated
if a client writes to it during the migration. This does not
check if the writes from the rebalance and the client actually
do overlap.

If dht_writev_cbk finds that the file is being migrated (PHASE1)
it will set an xattr on the destination file indicating the file
was updated by a non-rebalance client.
Rebalance checks if any other client has written to the dst file
and aborts the file migration if it finds the xattr.

updates gluster/glusterfs#308

Change-Id: I73aec28bc9dbb8da57c7425ec88c6b6af0fbc9dd
Signed-off-by: Susant Palai <spalai@redhat.com>
Signed-off-by: Raghavendra G <rgowdapp@redhat.com>
Signed-off-by: N Balachandran <nbalacha@redhat.com>

Fixed an issue in dht_populate_inode_for_dentry where a layout is
set in the inode without checking if it is already set. This overwrites
the value each time without freeing the already existing layout.

Change-Id: I651bf539a0b82b4ddc4c355890c16a8e91f5f1fd
BUG: 1541264
Signed-off-by: N Balachandran <nbalacha@redhat.com>

Variable search_unhashed is of type boolean, change it to integer type.
This fixes the warning increment of a boolean expression.

BUG: 1531987

Change-Id: Ibf153f6a9ad704da38bff346b6a21a71323ed9bb
Signed-off-by: Varsha Rao <varao@redhat.com>

The dht_(f)xattrop implementation did not implement
migration phase1/phase2 checks which could cause issues
with rebalance on sharded volumes.
This does not solve the issue where fops may reach the target
out of order.

Change-Id: I2416fc35115e60659e35b4b717fd51f20746586c
BUG: 1471031
Signed-off-by: N Balachandran <nbalacha@redhat.com>

Problem: In glusterfs code base we call mutex_lock/unlock to take
         reference/dereference for a object.Sometime it could be
         reason for lock contention also.

Solution: There is no need to use mutex to increase/decrease ref
          counter, instead of using mutex use gcc builtin ATOMIC
          operation.

Test:   I have not observed yet how much performance gain after apply
        this patch specific to glusterfs but i have tested same
        with below small program(mutex and atomic both) and
        get good difference.

static int numOuterLoops;
static void *
threadFunc(void *arg)
{
    int j;

    for (j = 0; j < numOuterLoops; j++) {
            __atomic_add_fetch (&glob, 1,__ATOMIC_ACQ_REL);
    }
    return NULL;
}

int
main(int argc, char *argv[])
{
    int opt, s, j;
    int numThreads;
    pthread_t *thread;
    int verbose;
    int64_t n = 0;

    if (argc < 2 ) {
     printf(" Please provide 2 args Num of threads && Outer Loop\n");
     exit (-1);
    }
    numThreads = atoi(argv[1]);
    numOuterLoops = atoi (argv[2]);

    if (1) {
        printf("\tthreads: %d; outer loops: %d;\n",
                numThreads, numOuterLoops);
    }

    thread = calloc(numThreads, sizeof(pthread_t));
    if (thread == NULL) {
        printf ("calloc error so exit\n");
        exit (-1);
    }

    __atomic_store (&glob, &n, __ATOMIC_RELEASE);
    for (j = 0; j < numThreads; j++) {
        s = pthread_create(&thread[j], NULL, threadFunc, NULL);
        if (s != 0) {
            printf ("pthread_create failed so exit\n");
            exit (-1);
        }
    }

    for (j = 0; j < numThreads; j++) {
        s = pthread_join(thread[j], NULL);
        if (s != 0) {
            printf ("pthread_join failed so exit\n");
            exit (-1);
        }
    }
    printf("glob value is %ld\n",__atomic_load_n (&glob,__ATOMIC_RELAXED));

    exit(0);
}

   time ./thr_count 800 800000
   threads: 800; outer loops: 800000;
   glob value is 640000000

real	1m10.288s
user	0m57.269s
sys	3m31.565s

time ./thr_count_atomic 800 800000
     threads: 800; outer loops: 800000;
glob value is 640000000

real	0m20.313s
user	1m20.558s
sys	0m0.028

Change-Id: Ie5030a52ea264875e002e108dd4b207b15ab7cc7
Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>

BUG: 1520974
Change-Id: I19ea40c888e88a7a4ac271168ed1820c2075be93
Signed-off-by: ShyamsundarR <srangana@redhat.com>

Problem: tierd was stopped only after detach commit
This makes the detach take a longer time. The detach
demotes the files to the cold brick and if the promotion
frequency is hit, then the tierd starts to promote files to
hot tier again.

Fix: stop tierd after detach start so the files get
demoted faster.

Note: the is_tier_enabled was not maintained properly.
That has been fixed too. some code clean up has been done.

Signed-off-by: hari gowtham <hgowtham@redhat.com>

Change-Id: I532f7410cea04fbb960105483810ea3560ca149b
BUG: 1446381

Problem: Sometime test case ./tests/bugs/bug-1371806_1.t is failing on
         centos due to race condition between fresh lookup and setxattr fop.

Solution: In selfheal code path we do save mds on inode_ctx, it was not
          serialize with lookup unwind. Due to this behavior after lookup
          unwind if mds is not saved on inode_ctx and if any subsequent
          setxattr fop call it has failed with ENOENT because
          no mds has found on inode ctx.To resolve it save mds on
          inode ctx has been serialize with lookup unwind.

BUG: 1498966
Change-Id: I8d4bb40a6cbf0cec35d181ec0095cc7142b02e29
Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>

..
the brick file system does not support fallocate.

Change-Id: Id76cda2d8bb3b223b779e5e7a34f17c8bfa6283c
BUG: 1488103
Signed-off-by: Susant Palai <spalai@redhat.com>