Lustre devel - Aug 2007 - [Bug 11270] eliminate client locks in face of contention

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https://bugzilla.lustre.org/show_bug.cgi?id=11270



acc-sm test fails (sanityN, test #12) after applying lockless patch to the 
current b1_6 branch:

<5> Lustre: 7616:0:(debug.c:436:libcfs_debug_mark_buffer()) DEBUG MARKER: 
start dir: /mnt/lustre/lockdir=50008 file: /mnt/lustre/lockdir/lockfile=50007
<5> LustreError: 7362:0:(ldlm_lockd.c:1269:ldlm_handle_cp_callback())
change
resource!
<5> LustreError: 7362:0:(ldlm_lock.c:771:ldlm_granted_list_add_lock()) 
ASSERTION(list_empty(&lock->l_res_link)) failed
<5> LustreError: 7362:0:(tracefile.c:433:libcfs_assertion_failed()) LBUG
<5> Lustre: 7362:0:(linux-debug.c:168:libcfs_debug_dumpstack()) showing
stack
for process 7362
<5> ldlm_cb_05    R running     0  7362      1          7363  7361 (L-TLB)
<5> 00000000 de05ff8a cdce6a2c 0017ce28 00000e74 cdce6a2c ce556656
00000000
<5>        00000000 0000003b d1da499c c4cf8000 00000708 cdce6a2c 46d2d5fc 
00094e79
<5>        dbcaa03c 00000000 c16f39b8 d3fbffec de1b41ce dbcaa03c c16f39b8 
ffffffff
<5> Call Trace:
<5>  [<c0107324>] show_stack+0x80/0x96
<5>  [<c011d650>] show_task+0x13e/0x22d
<5>  [<de052ea7>] lbug_with_loc+0x7b/0xc7 [libcfs]
<5>  [<de05c533>] trace_assertion_failed+0x0/0x9b [libcfs]
<5>  [<de14681d>] ldlm_granted_list_add_lock+0x65c/0x6b3 [ptlrpc]
<5>  [<de1468f5>] ldlm_grant_lock_with_skiplist+0x81/0x23d [ptlrpc]
<5>  [<de146b2a>] ldlm_grant_lock+0x79/0x27a [ptlrpc]
<5>  [<de17d1d7>] ldlm_handle_cp_callback+0x1e1/0xa0f [ptlrpc]
<5>  [<de17fb3d>] ldlm_callback_handler+0x1650/0x2e26 [ptlrpc]
<5>  [<de1b1d9a>] ptlrpc_server_handle_request+0x8fb/0x1c11 [ptlrpc]
<5>  [<de1b41ce>] ptlrpc_main+0x6f1/0xea3 [ptlrpc]
<5>  [<c0105299>] kernel_thread_helper+0x5/0xb