High load due to many processes blocked in mvfs filesystem

Issue

• Many blocked task messages reported in the system log:

INFO: task cc1plus:23314 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
cc1plus       D 0000000000000000     0 23314  23305 0x00000000
 ffff8811b9d0bab8 0000000000000086 0000000000000000 ffff880028256768
 ffff880028256798 ffff880028256768 ffff88007bcd3538 0000000000009faf
 ffff8811f7093098 ffff8811b9d0bfd8 000000000000fb88 ffff8811f7093098
Call Trace:
 [<ffffffff8150ea05>] schedule_timeout+0x215/0x2e0
 [<ffffffff810522fd>] ? check_preempt_curr+0x6d/0x90
 [<ffffffff8106317e>] ? try_to_wake_up+0x24e/0x3e0
 [<ffffffff8150f922>] __down+0x72/0xb0
 [<ffffffff8109ca61>] down+0x41/0x50
 [<ffffffffa06ec093>] mfs_afphold+0x29/0xc4 [mvfs]
 [<ffffffffa06e02a7>] mvfs_enter_fs+0xc4/0x104 [mvfs]
 [<ffffffffa0708ebd>] mvfs_get_thread_ptr+0x19/0x1b [mvfs]
 [<ffffffffa0714c54>] mdki_linux_init_call_data+0x1e/0x26 [mvfs]
 [<ffffffffa070c6ec>] vnode_iop_permission+0x24/0x5d [mvfs]
 [<ffffffff8119061d>] __link_path_walk+0xad/0x1030
 [<ffffffff8119182a>] path_walk+0x6a/0xe0
 [<ffffffff811919fb>] do_path_lookup+0x5b/0xa0
 [<ffffffff81182540>] ? get_empty_filp+0xa0/0x180
 [<ffffffff8119293b>] do_filp_open+0xfb/0xdd0
 [<ffffffff8104757c>] ? __do_page_fault+0x1ec/0x480
 [<ffffffff810e6dd5>] ? call_rcu_sched+0x15/0x20
 [<ffffffff811a1b60>] ? mntput_no_expire+0x30/0x110
 [<ffffffff8119f5e2>] ? alloc_fd+0x92/0x160
 [<ffffffff8117df59>] do_sys_open+0x69/0x140
 [<ffffffff8100c535>] ? math_state_restore+0x45/0x60
 [<ffffffff8117e070>] sys_open+0x20/0x30
 [<ffffffff8100b072>] system_call_fastpath+0x16/0x1b