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* FS-Cache: Don't use spin_is_locked() in assertionsDavid Howells2013-06-191-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Under certain circumstances, spin_is_locked() is hardwired to 0 - even when the code would normally be in a locked section where it should return 1. This means it cannot be used for an assertion that checks that a spinlock is locked. Remove such usages from FS-Cache. The following oops might otherwise be observed: FS-Cache: Assertion failed BUG: failure at fs/fscache/operation.c:270/fscache_start_operations()! Kernel panic - not syncing: BUG! CPU: 0 PID: 10 Comm: kworker/u2:1 Not tainted 3.10.0-rc1-00133-ge7ebb75 #2 Workqueue: fscache_operation fscache_op_work_func [fscache] 7f091c48 603c8947 7f090000 7f9b1361 7f25f080 00000001 7f26d440 7f091c90 60299eb8 7f091d90 602951c5 7f26d440 3000000008 7f091da0 7f091cc0 7f091cd0 00000007 00000007 00000006 7f091ae0 00000010 0000010e 7f9af330 7f091ae0 Call Trace: 7f091c88: [<60299eb8>] dump_stack+0x17/0x19 7f091c98: [<602951c5>] panic+0xf4/0x1e9 7f091d38: [<6002b10e>] set_signals+0x1e/0x40 7f091d58: [<6005b89e>] __wake_up+0x4e/0x70 7f091d98: [<7f9aa003>] fscache_start_operations+0x43/0x50 [fscache] 7f091da8: [<7f9aa1e3>] fscache_op_complete+0x1d3/0x220 [fscache] 7f091db8: [<60082985>] unlock_page+0x55/0x60 7f091de8: [<7fb25bb0>] cachefiles_read_copier+0x250/0x330 [cachefiles] 7f091e58: [<7f9ab03c>] fscache_op_work_func+0xac/0x120 [fscache] 7f091e88: [<6004d5b0>] process_one_work+0x250/0x3a0 7f091ef8: [<6004edc7>] worker_thread+0x177/0x2a0 7f091f38: [<6004ec50>] worker_thread+0x0/0x2a0 7f091f58: [<60054418>] kthread+0xd8/0xe0 7f091f68: [<6005bb27>] finish_task_switch.isra.64+0x37/0xa0 7f091fd8: [<600185cf>] new_thread_handler+0x8f/0xb0 Reported-by: Milosz Tanski <milosz@adfin.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-and-tested-By: Milosz Tanski <milosz@adfin.com>
* FS-Cache: The retrieval remaining-pages counter needs to be atomic_tDavid Howells2013-06-192-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct fscache_retrieval contains a count of the number of pages that still need some processing (n_pages). This is decremented as the pages are processed. However, this needs to be atomic as fscache_retrieval_complete() (I think) just occasionally may be called from cachefiles_read_backing_file() and cachefiles_read_copier() simultaneously. This happens when an fscache_read_or_alloc_pages() request containing a lot of pages (say a couple of hundred) is being processed. The read on each backing page is dispatched individually because we need to insert a monitor into the waitqueue to catch when the read completes. However, under low-memory conditions, we might be forced to wait in the allocator - and this gives the I/O on the backing page a chance to complete first. When the I/O completes, fscache_enqueue_retrieval() chucks the retrieval onto the workqueue without waiting for the operation to finish the initial I/O dispatch (we want to release any pages we can as soon as we can), thus both can end up running simultaneously and potentially attempting to partially complete the retrieval simultaneously (ENOMEM may occur, backing pages may already be in the page cache). This was demonstrated by parallelling the non-atomic counter with an atomic counter and printing both of them when the assertion fails. At this point, the atomic counter has reached zero, but the non-atomic counter has not. To fix this, make the counter an atomic_t. This results in the following bug appearing FS-Cache: Assertion failed 3 == 5 is false ------------[ cut here ]------------ kernel BUG at fs/fscache/operation.c:421! or FS-Cache: Assertion failed 3 == 5 is false ------------[ cut here ]------------ kernel BUG at fs/fscache/operation.c:414! With a backtrace like the following: RIP: 0010:[<ffffffffa0211b1d>] fscache_put_operation+0x1ad/0x240 [fscache] Call Trace: [<ffffffffa0213185>] fscache_retrieval_work+0x55/0x270 [fscache] [<ffffffffa0213130>] ? fscache_retrieval_work+0x0/0x270 [fscache] [<ffffffff81090b10>] worker_thread+0x170/0x2a0 [<ffffffff81096d10>] ? autoremove_wake_function+0x0/0x40 [<ffffffff810909a0>] ? worker_thread+0x0/0x2a0 [<ffffffff81096966>] kthread+0x96/0xa0 [<ffffffff8100c0ca>] child_rip+0xa/0x20 [<ffffffff810968d0>] ? kthread+0x0/0xa0 [<ffffffff8100c0c0>] ? child_rip+0x0/0x20 Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-and-tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* cachefiles: remove unused macro list_to_page()Haicheng Li2013-06-191-2/+0
| | | | | | | Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* FS-Cache: Simplify cookie retention for fscache_objects, fixing oopsDavid Howells2013-06-1912-257/+230
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Simplify the way fscache cache objects retain their cookie. The way I implemented the cookie storage handling made synchronisation a pain (ie. the object state machine can't rely on the cookie actually still being there). Instead of the the object being detached from the cookie and the cookie being freed in __fscache_relinquish_cookie(), we defer both operations: (*) The detachment of the object from the list in the cookie now takes place in fscache_drop_object() and is thus governed by the object state machine (fscache_detach_from_cookie() has been removed). (*) The release of the cookie is now in fscache_object_destroy() - which is called by the cache backend just before it frees the object. This means that the fscache_cookie struct is now available to the cache all the way through from ->alloc_object() to ->drop_object() and ->put_object() - meaning that it's no longer necessary to take object->lock to guarantee access. However, __fscache_relinquish_cookie() doesn't wait for the object to go all the way through to destruction before letting the netfs proceed. That would massively slow down the netfs. Since __fscache_relinquish_cookie() leaves the cookie around, in must therefore break all attachments to the netfs - which includes ->def, ->netfs_data and any outstanding page read/writes. To handle this, struct fscache_cookie now has an n_active counter: (1) This starts off initialised to 1. (2) Any time the cache needs to get at the netfs data, it calls fscache_use_cookie() to increment it - if it is not zero. If it was zero, then access is not permitted. (3) When the cache has finished with the data, it calls fscache_unuse_cookie() to decrement it. This does a wake-up on it if it reaches 0. (4) __fscache_relinquish_cookie() decrements n_active and then waits for it to reach 0. The initialisation to 1 in step (1) ensures that we only get wake ups when we're trying to get rid of the cookie. This leaves __fscache_relinquish_cookie() a lot simpler. *** This fixes a problem in the current code whereby if fscache_invalidate() is followed sufficiently quickly by fscache_relinquish_cookie() then it is possible for __fscache_relinquish_cookie() to have detached the cookie from the object and cleared the pointer before a thread is dispatched to process the invalidation state in the object state machine. Since the pending write clearance was deferred to the invalidation state to make it asynchronous, we need to either wait in relinquishment for the stores tree to be cleared in the invalidation state or we need to handle the clearance in relinquishment. Further, if the relinquishment code does clear the tree, then the invalidation state need to make the clearance contingent on still having the cookie to hand (since that's where the tree is rooted) and we have to prevent the cookie from disappearing for the duration. This can lead to an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000000c ... RIP: 0010:[<ffffffff8151023e>] _spin_lock+0xe/0x30 ... CR2: 000000000000000c ... ... Process kslowd002 (...) .... Call Trace: [<ffffffffa01c3278>] fscache_invalidate_writes+0x38/0xd0 [fscache] [<ffffffff810096f0>] ? __switch_to+0xd0/0x320 [<ffffffff8105e759>] ? find_busiest_queue+0x69/0x150 [<ffffffff8110ddd4>] ? slow_work_enqueue+0x104/0x180 [<ffffffffa01c1303>] fscache_object_slow_work_execute+0x5e3/0x9d0 [fscache] [<ffffffff81096b67>] ? bit_waitqueue+0x17/0xd0 [<ffffffff8110e233>] slow_work_execute+0x233/0x310 [<ffffffff8110e515>] slow_work_thread+0x205/0x360 [<ffffffff81096ca0>] ? autoremove_wake_function+0x0/0x40 [<ffffffff8110e310>] ? slow_work_thread+0x0/0x360 [<ffffffff81096936>] kthread+0x96/0xa0 [<ffffffff8100c0ca>] child_rip+0xa/0x20 [<ffffffff810968a0>] ? kthread+0x0/0xa0 [<ffffffff8100c0c0>] ? child_rip+0x0/0x20 The parameter to fscache_invalidate_writes() was object->cookie which is NULL. Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* FS-Cache: Fix object state machine to have separate work and wait statesDavid Howells2013-06-1910-577/+605
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix object state machine to have separate work and wait states as that makes it easier to envision. There are now three kinds of state: (1) Work state. This is an execution state. No event processing is performed by a work state. The function attached to a work state returns a pointer indicating the next state to which the OSM should transition. Returning NO_TRANSIT repeats the current state, but goes back to the scheduler first. (2) Wait state. This is an event processing state. No execution is performed by a wait state. Wait states are just tables of "if event X occurs, clear it and transition to state Y". The dispatcher returns to the scheduler if none of the events in which the wait state has an interest are currently pending. (3) Out-of-band state. This is a special work state. Transitions to normal states can be overridden when an unexpected event occurs (eg. I/O error). Instead the dispatcher disables and clears the OOB event and transits to the specified work state. This then acts as an ordinary work state, though object->state points to the overridden destination. Returning NO_TRANSIT resumes the overridden transition. In addition, the states have names in their definitions, so there's no need for tables of state names. Further, the EV_REQUEUE event is no longer necessary as that is automatic for work states. Since the states are now separate structs rather than values in an enum, it's not possible to use comparisons other than (non-)equality between them, so use some object->flags to indicate what phase an object is in. The EV_RELEASE, EV_RETIRE and EV_WITHDRAW events have been squished into one (EV_KILL). An object flag now carries the information about retirement. Similarly, the RELEASING, RECYCLING and WITHDRAWING states have been merged into an KILL_OBJECT state and additional states have been added for handling waiting dependent objects (JUMPSTART_DEPS and KILL_DEPENDENTS). A state has also been added for synchronising with parent object initialisation (WAIT_FOR_PARENT) and another for initiating look up (PARENT_READY). Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* FS-Cache: Wrap checks on object stateDavid Howells2013-06-196-21/+40
| | | | | | | | | | | | Wrap checks on object state (mostly outside of fs/fscache/object.c) with inline functions so that the mechanism can be replaced. Some of the state checks within object.c are left as-is as they will be replaced. Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* FS-Cache: Uninline fscache_object_init()David Howells2013-06-192-38/+40
| | | | | | | | | Uninline fscache_object_init() so as not to expose some of the FS-Cache internals to the cache backend. Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* FS-Cache: Don't sleep in page release if __GFP_FS is not setDavid Howells2013-06-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't sleep in __fscache_maybe_release_page() if __GFP_FS is not set. This goes some way towards mitigating fscache deadlocking against ext4 by way of the allocator, eg: INFO: task flush-8:0:24427 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. flush-8:0 D ffff88003e2b9fd8 0 24427 2 0x00000000 ffff88003e2b9138 0000000000000046 ffff880012e3a040 ffff88003e2b9fd8 0000000000011c80 ffff88003e2b9fd8 ffffffff81a10400 ffff880012e3a040 0000000000000002 ffff880012e3a040 ffff88003e2b9098 ffffffff8106dcf5 Call Trace: [<ffffffff8106dcf5>] ? __lock_is_held+0x31/0x53 [<ffffffff81219b61>] ? radix_tree_lookup_element+0xf4/0x12a [<ffffffff81454bed>] schedule+0x60/0x62 [<ffffffffa01d349c>] __fscache_wait_on_page_write+0x8b/0xa5 [fscache] [<ffffffff810498a8>] ? __init_waitqueue_head+0x4d/0x4d [<ffffffffa01d393a>] __fscache_maybe_release_page+0x30c/0x324 [fscache] [<ffffffffa01d369a>] ? __fscache_maybe_release_page+0x6c/0x324 [fscache] [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170 [<ffffffffa01fd7b2>] nfs_fscache_release_page+0x68/0x94 [nfs] [<ffffffffa01ef73e>] nfs_release_page+0x7e/0x86 [nfs] [<ffffffff810aa553>] try_to_release_page+0x32/0x3b [<ffffffff810b6c70>] shrink_page_list+0x535/0x71a [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170 [<ffffffff810b7352>] shrink_inactive_list+0x20a/0x2dd [<ffffffff81071a13>] ? mark_held_locks+0xbe/0xea [<ffffffff810b7a65>] shrink_lruvec+0x34c/0x3eb [<ffffffff810b7bd3>] do_try_to_free_pages+0xcf/0x355 [<ffffffff810b7fc8>] try_to_free_pages+0x9a/0xa1 [<ffffffff810b08d2>] __alloc_pages_nodemask+0x494/0x6f7 [<ffffffff810d9a07>] kmem_getpages+0x58/0x155 [<ffffffff810dc002>] fallback_alloc+0x120/0x1f3 [<ffffffff8106db23>] ? trace_hardirqs_off+0xd/0xf [<ffffffff810dbed3>] ____cache_alloc_node+0x177/0x186 [<ffffffff81162a6c>] ? ext4_init_io_end+0x1c/0x37 [<ffffffff810dc403>] kmem_cache_alloc+0xf1/0x176 [<ffffffff810b17ac>] ? test_set_page_writeback+0x101/0x113 [<ffffffff81162a6c>] ext4_init_io_end+0x1c/0x37 [<ffffffff81162ce4>] ext4_bio_write_page+0x20f/0x3af [<ffffffff8115cc02>] mpage_da_submit_io+0x26e/0x2f6 [<ffffffff811088e5>] ? __find_get_block_slow+0x38/0x133 [<ffffffff81161348>] mpage_da_map_and_submit+0x3a7/0x3bd [<ffffffff81161a60>] ext4_da_writepages+0x30d/0x426 [<ffffffff810b3359>] do_writepages+0x1c/0x2a [<ffffffff81102f4d>] __writeback_single_inode+0x3e/0xe5 [<ffffffff81103995>] writeback_sb_inodes+0x1bd/0x2f4 [<ffffffff81103b3b>] __writeback_inodes_wb+0x6f/0xb4 [<ffffffff81103c81>] wb_writeback+0x101/0x195 [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170 [<ffffffff811043aa>] ? wb_do_writeback+0xaa/0x173 [<ffffffff8110434a>] wb_do_writeback+0x4a/0x173 [<ffffffff81071bbc>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81038554>] ? del_timer+0x4b/0x5b [<ffffffff811044e0>] bdi_writeback_thread+0x6d/0x147 [<ffffffff81104473>] ? wb_do_writeback+0x173/0x173 [<ffffffff81048fbc>] kthread+0xd0/0xd8 [<ffffffff81455eb2>] ? _raw_spin_unlock_irq+0x29/0x3e [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55 [<ffffffff81456aac>] ret_from_fork+0x7c/0xb0 [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55 2 locks held by flush-8:0/24427: #0: (&type->s_umount_key#41){.+.+..}, at: [<ffffffff810e3b73>] grab_super_passive+0x4c/0x76 #1: (jbd2_handle){+.+...}, at: [<ffffffff81190d81>] start_this_handle+0x475/0x4ea The problem here is that another thread, which is attempting to write the to-be-stored NFS page to the on-ext4 cache file is waiting for the journal lock, eg: INFO: task kworker/u:2:24437 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u:2 D ffff880039589768 0 24437 2 0x00000000 ffff8800395896d8 0000000000000046 ffff8800283bf040 ffff880039589fd8 0000000000011c80 ffff880039589fd8 ffff880039f0b040 ffff8800283bf040 0000000000000006 ffff8800283bf6b8 ffff880039589658 ffffffff81071a13 Call Trace: [<ffffffff81071a13>] ? mark_held_locks+0xbe/0xea [<ffffffff81455e73>] ? _raw_spin_unlock_irqrestore+0x3a/0x50 [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170 [<ffffffff81071bbc>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81454bed>] schedule+0x60/0x62 [<ffffffff81190c23>] start_this_handle+0x317/0x4ea [<ffffffff810498a8>] ? __init_waitqueue_head+0x4d/0x4d [<ffffffff81190fcc>] jbd2__journal_start+0xb3/0x12e [<ffffffff81176606>] __ext4_journal_start_sb+0xb2/0xc6 [<ffffffff8115f137>] ext4_da_write_begin+0x109/0x233 [<ffffffff810a964d>] generic_file_buffered_write+0x11a/0x264 [<ffffffff811032cf>] ? __mark_inode_dirty+0x2d/0x1ee [<ffffffff810ab1ab>] __generic_file_aio_write+0x2a5/0x2d5 [<ffffffff810ab24a>] generic_file_aio_write+0x6f/0xd0 [<ffffffff81159a2c>] ext4_file_write+0x38c/0x3c4 [<ffffffff810e0915>] do_sync_write+0x91/0xd1 [<ffffffffa00a17f0>] cachefiles_write_page+0x26f/0x310 [cachefiles] [<ffffffffa01d470b>] fscache_write_op+0x21e/0x37a [fscache] [<ffffffff81455eb2>] ? _raw_spin_unlock_irq+0x29/0x3e [<ffffffffa01d2479>] fscache_op_work_func+0x78/0xd7 [fscache] [<ffffffff8104455a>] process_one_work+0x232/0x3a8 [<ffffffff810444ff>] ? process_one_work+0x1d7/0x3a8 [<ffffffff81044ee0>] worker_thread+0x214/0x303 [<ffffffff81044ccc>] ? manage_workers+0x245/0x245 [<ffffffff81048fbc>] kthread+0xd0/0xd8 [<ffffffff81455eb2>] ? _raw_spin_unlock_irq+0x29/0x3e [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55 [<ffffffff81456aac>] ret_from_fork+0x7c/0xb0 [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55 4 locks held by kworker/u:2/24437: #0: (fscache_operation){.+.+.+}, at: [<ffffffff810444ff>] process_one_work+0x1d7/0x3a8 #1: ((&op->work)){+.+.+.}, at: [<ffffffff810444ff>] process_one_work+0x1d7/0x3a8 #2: (sb_writers#14){.+.+.+}, at: [<ffffffff810ab22c>] generic_file_aio_write+0x51/0xd0 #3: (&sb->s_type->i_mutex_key#19){+.+.+.}, at: [<ffffffff810ab236>] generic_file_aio_write+0x5b/0x fscache already tries to cancel pending stores, but it can't cancel a write for which I/O is already in progress. An alternative would be to accept writing garbage to the cache under extreme circumstances and to kill the afflicted cache object if we have to do this. However, we really need to know how strapped the allocator is before deciding to do that. Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* CacheFiles: name i_mutex lock class explicitlyJ. Bruce Fields2013-06-191-1/+1
| | | | | | | | | | | | | Just some cleanup. (And note the caller of this function may, for example, call vfs_unlink on a child, so the "1" (I_MUTEX_PARENT) really was what was intended here.) Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* fs/fscache: remove spin_lock() from the condition in while()Sebastian Andrzej Siewior2013-06-191-6/+10
| | | | | | | | | | | | The spinlock() within the condition in while() will cause a compile error if it is not a function. This is not a problem on mainline but it does not look pretty and there is no reason to do it that way. That patch writes it a little differently and avoids the double condition. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* Add wait_on_atomic_t() and wake_up_atomic_t()David Howells2013-05-152-0/+112
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add wait_on_atomic_t() and wake_up_atomic_t() to indicate became-zero events on atomic_t types. This uses the bit-wake waitqueue table. The key is set to a value outside of the number of bits in a long so that wait_on_bit() won't be woken up accidentally. What I'm using this for is: in a following patch I add a counter to struct fscache_cookie to count the number of outstanding operations that need access to netfs data. The way this works is: (1) When a cookie is allocated, the counter is initialised to 1. (2) When an operation wants to access netfs data, it calls atomic_inc_unless() to increment the counter before it does so. If it was 0, then the counter isn't incremented, the operation isn't permitted to access the netfs data (which might by this point no longer exist) and the operation aborts in some appropriate manner. (3) When an operation finishes with the netfs data, it decrements the counter and if it reaches 0, calls wake_up_atomic_t() on it - the assumption being that it was the last blocker. (4) When a cookie is released, the counter is decremented and the releaser uses wait_on_atomic_t() to wait for the counter to become 0 - which should indicate no one is using the netfs data any longer. The netfs data can then be destroyed. There are some alternatives that I have thought of and that have been suggested by Tejun Heo: (A) Using wait_on_bit() to wait on a bit in the counter. This doesn't work because if that bit happens to be 0 then the wait won't happen - even if the counter is non-zero. (B) Using wait_on_bit() to wait on a flag elsewhere which is cleared when the counter reaches 0. Such a flag would be redundant and would add complexity. (C) Adding a waitqueue to fscache_cookie - this would expand that struct by several words for an event that happens just once in each cookie's lifetime. Further, cookies are generally per-file so there are likely to be a lot of them. (D) Similar to (C), but add a pointer to a waitqueue in the cookie instead of a waitqueue. This would add single word per cookie and so would be less of an expansion - but still an expansion. (E) Adding a static waitqueue to the fscache module. Generally this would be fine, but under certain circumstances many cookies will all get added at the same time (eg. NFS umount, cache withdrawal) thereby presenting scaling issues. Note that the wait may be significant as disk I/O may be in progress. So, I think reusing the wait_on_bit() waitqueue set is reasonable. I don't make much use of the waitqueue I need on a per-cookie basis, but sometimes I have a huge flood of the cookies to deal with. I also don't want to add a whole new set of global waitqueue tables specifically for the dec-to-0 event if I can reuse the bit tables. Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Milosz Tanski <milosz@adfin.com> Acked-by: Jeff Layton <jlayton@redhat.com>
* Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds2013-05-1410-146/+119
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 update from Ted Ts'o: "Fixed regressions (two stability regressions and a performance regression) introduced during the 3.10-rc1 merge window. Also included is a bug fix relating to allocating blocks after resizing an ext3 file system when using the ext4 file system driver" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: jbd,jbd2: fix oops in jbd2_journal_put_journal_head() ext4: revert "ext4: use io_end for multiple bios" ext4: limit group search loop for non-extent files ext4: fix fio regression
| * jbd,jbd2: fix oops in jbd2_journal_put_journal_head()Jan Kara2013-05-131-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ae4647fb (jbd2: reduce journal_head size) introduced a regression where we occasionally hit panic in jbd2_journal_put_journal_head() because of wrong b_jcount. The bug is caused by gcc making 64-bit access to 32-bit bitfield and thus clobbering b_jcount. At least for now, those 8 bytes saved in struct journal_head are not worth the trouble with gcc bitfield handling so revert that part of the patch. Reported-by: EUNBONG SONG <eunb.song@samsung.com> Reported-by: Tony Luck <tony.luck@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * ext4: revert "ext4: use io_end for multiple bios"Theodore Ts'o2013-05-113-129/+85
| | | | | | | | | | | | | | | | | | | | | | This reverts commit 4eec708d263f0ee10861d69251708a225b64cac7. Multiple users have reported crashes which is apparently caused by this commit. Thanks to Dmitry Monakhov for bisecting it. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Dmitry Monakhov <dmonakhov@openvz.org> Cc: Jan Kara <jack@suse.cz>
| * ext4: limit group search loop for non-extent filesLachlan McIlroy2013-05-051-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the case where we are allocating for a non-extent file, we must limit the groups we allocate from to those below 2^32 blocks, and ext4_mb_regular_allocator() attempts to do this initially by putting a cap on ngroups for the subsequent search loop. However, the initial target group comes in from the allocation context (ac), and it may already be beyond the artificially limited ngroups. In this case, the limit if (group == ngroups) group = 0; at the top of the loop is never true, and the loop will run away. Catch this case inside the loop and reset the search to start at group 0. [sandeen@redhat.com: add commit msg & comments] Signed-off-by: Lachlan McIlroy <lmcilroy@redhat.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
| * ext4: fix fio regressionYan, Zheng2013-05-035-14/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We (Linux Kernel Performance project) found a regression introduced by commit: f7fec032aa ext4: track all extent status in extent status tree The commit causes about 20% performance decrease in fio random write test. Profiler shows that rb_next() uses a lot of CPU time. The call stack is: rb_next ext4_es_find_delayed_extent ext4_map_blocks _ext4_get_block ext4_get_block_write __blockdev_direct_IO ext4_direct_IO generic_file_direct_write __generic_file_aio_write ext4_file_write aio_rw_vect_retry aio_run_iocb do_io_submit sys_io_submit system_call_fastpath io_submit td_io_getevents io_u_queued_complete thread_main main __libc_start_main The cause is that ext4_es_find_delayed_extent() doesn't have an upper bound, it keeps searching until a delayed extent is found. When there are a lots of non-delayed entries in the extent state tree, ext4_es_find_delayed_extent() may uses a lot of CPU time. Reported-by: LKP project <lkp@linux.intel.com> Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Cc: "Theodore Ts'o" <tytso@mit.edu>
* | Merge branch 'for-3.10-fixes' of ↵Linus Torvalds2013-05-141-0/+9
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue fix from Tejun Heo: "A fix for a workqueue_congested() regression that broke fscache" * 'for-3.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: workqueue_congested() shouldn't translate WORK_CPU_UNBOUND into node number
| * | workqueue: workqueue_congested() shouldn't translate WORK_CPU_UNBOUND into ↵Tejun Heo2013-05-101-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | node number df2d5ae499 ("workqueue: map an unbound workqueues to multiple per-node pool_workqueues") made unbound workqueues to map to multiple per-node pool_workqueues and accordingly updated workqueue_contested() so that, for unbound workqueues, it maps the specified @cpu to the NUMA node number to obtain the matching pool_workqueue to query the congested state. Before this change, workqueue_congested() ignored @cpu for unbound workqueues as there was only one pool_workqueue and some users (fscache) called it with WORK_CPU_UNBOUND. After the commit, this causes the following oops as WORK_CPU_UNBOUND gets translated to garbage by cpu_to_node(). BUG: unable to handle kernel paging request at ffff8803598d98b8 IP: [<ffffffff81043b7e>] unbound_pwq_by_node+0xa1/0xfa PGD 2421067 PUD 0 Oops: 0000 [#1] SMP CPU: 1 PID: 2689 Comm: cat Tainted: GF 3.9.0-fsdevel+ #4 task: ffff88003d801040 ti: ffff880025806000 task.ti: ffff880025806000 RIP: 0010:[<ffffffff81043b7e>] [<ffffffff81043b7e>] unbound_pwq_by_node+0xa1/0xfa RSP: 0018:ffff880025807ad8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff8800388a2400 RCX: 0000000000000003 RDX: ffff880025807fd8 RSI: ffffffff81a31420 RDI: ffff88003d8016e0 RBP: ffff880025807ae8 R08: ffff88003d801730 R09: ffffffffa00b4898 R10: ffffffff81044217 R11: ffff88003d801040 R12: 0000000064206e97 R13: ffff880036059d98 R14: ffff880038cc8080 R15: ffff880038cc82d0 FS: 00007f21afd9c740(0000) GS:ffff88003d100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff8803598d98b8 CR3: 000000003df49000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff8800388a2400 0000000000000002 ffff880025807b18 ffffffff810442ce ffffffff81044217 ffff880000000002 ffff8800371b4080 ffff88003d112ec0 ffff880025807b38 ffffffffa00810b0 ffff880036059d88 ffff880036059be8 Call Trace: [<ffffffff810442ce>] workqueue_congested+0xb7/0x12c [<ffffffffa00810b0>] fscache_enqueue_object+0xb2/0xe8 [fscache] [<ffffffffa007facd>] __fscache_acquire_cookie+0x3b9/0x56c [fscache] [<ffffffffa00ad8fe>] nfs_fscache_set_inode_cookie+0xee/0x132 [nfs] [<ffffffffa009e112>] do_open+0x9/0xd [nfs] [<ffffffff810e804a>] do_dentry_open+0x175/0x24b [<ffffffff810e8298>] finish_open+0x41/0x51 Fix it by using smp_processor_id() if @cpu is WORK_CPU_UNBOUND. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: David Howells <dhowells@redhat.com> Tested-and-Acked-by: David Howells <dhowells@redhat.com>
* | | Merge branch 'merge' of ↵Linus Torvalds2013-05-1445-206/+763
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc fixes from Benjamin Herrenschmidt: "This is mostly bug fixes (some of them regressions, some of them I deemed worth merging now) along with some patches from Li Zhong hooking up the new context tracking stuff (for the new full NO_HZ)" * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits) powerpc: Set show_unhandled_signals to 1 by default powerpc/perf: Fix setting of "to" addresses for BHRB powerpc/pmu: Fix order of interpreting BHRB target entries powerpc/perf: Move BHRB code into CONFIG_PPC64 region powerpc: select HAVE_CONTEXT_TRACKING for pSeries powerpc: Use the new schedule_user API on userspace preemption powerpc: Exit user context on notify resume powerpc: Exception hooks for context tracking subsystem powerpc: Syscall hooks for context tracking subsystem powerpc/booke64: Fix kernel hangs at kernel_dbg_exc powerpc: Fix irq_set_affinity() return values powerpc: Provide __bswapdi2 powerpc/powernv: Fix starting of secondary CPUs on OPALv2 and v3 powerpc/powernv: Detect OPAL v3 API version powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning again powerpc: Make CONFIG_RTAS_PROC depend on CONFIG_PROC_FS powerpc: Bring all threads online prior to migration/hibernation powerpc/rtas_flash: Fix validate_flash buffer overflow issue powerpc/kexec: Fix kexec when using VMX optimised memcpy powerpc: Fix build errors STRICT_MM_TYPECHECKS ...
| * | | powerpc: Set show_unhandled_signals to 1 by defaultBenjamin Herrenschmidt2013-05-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Just like other architectures Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/perf: Fix setting of "to" addresses for BHRBMichael Neuling2013-05-141-1/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we only set the "to" address in the branch stack when the CPU explicitly gives us a value. Unfortunately it only does this for XL form branches (eg blr, bctr, bctar) and not I and B form branches (eg b, bc). Fortunately if we read the instruction from memory we can extract the offset of a branch and calculate the target address. This adds a function power_pmu_bhrb_to() to calculate the target/to address of the corresponding I and B form branches. It handles branches in both user and kernel spaces. It also plumbs this into the perf brhb reading code. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/pmu: Fix order of interpreting BHRB target entriesMichael Neuling2013-05-141-43/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current Branch History Rolling Buffer (BHRB) code misinterprets the order of entries in the hardware buffer. It assumes that a branch target address will be read _after_ its corresponding branch. In reality the branch target comes before (lower mfbhrb entry) it's corresponding branch. This is a rewrite of the code to take this into account. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/perf: Move BHRB code into CONFIG_PPC64 regionMichael Neuling2013-05-141-121/+127
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new Branch History Rolling buffer (BHRB) code is only useful on 64bit processors, so move it into the #ifdef CONFIG_PPC64 region. This avoids code bloat on 32bit systems. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: select HAVE_CONTEXT_TRACKING for pSeriesLi Zhong2013-05-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Start context tracking support from pSeries. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Use the new schedule_user API on userspace preemptionLi Zhong2013-05-142-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch corresponds to [PATCH] x86: Use the new schedule_user API on userspace preemption commit 0430499ce9d78691f3985962021b16bf8f8a8048 Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Exit user context on notify resumeLi Zhong2013-05-141-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows RCU usage in do_notify_resume, e.g. signal handling. It corresponds to [PATCH] x86: Exit RCU extended QS on notify resume commit edf55fda35c7dc7f2d9241c3abaddaf759b457c6 Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Exception hooks for context tracking subsystemLi Zhong2013-05-143-45/+112
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the exception hooks for context tracking subsystem, including data access, program check, single step, instruction breakpoint, machine check, alignment, fp unavailable, altivec assist, unknown exception, whose handlers might use RCU. This patch corresponds to [PATCH] x86: Exception hooks for userspace RCU extended QS commit 6ba3c97a38803883c2eee489505796cb0a727122 But after the exception handling moved to generic code, and some changes in following two commits: 56dd9470d7c8734f055da2a6bac553caf4a468eb context_tracking: Move exception handling to generic code 6c1e0256fad84a843d915414e4b5973b7443d48d context_tracking: Restore correct previous context state on exception exit it is able for exception hooks to use the generic code above instead of a redundant arch implementation. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Syscall hooks for context tracking subsystemLi Zhong2013-05-142-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the syscall slow path hooks for context tracking subsystem, corresponding to [PATCH] x86: Syscall hooks for userspace RCU extended QS commit bf5a3c13b939813d28ce26c01425054c740d6731 TIF_MEMDIE is moved to the second 16-bits (with value 17), as it seems there is no asm code using it. TIF_NOHZ is added to _TIF_SYCALL_T_OR_A, so it is better for it to be in the same 16 bits with others in the group, so in the asm code, andi. with this group could work. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/booke64: Fix kernel hangs at kernel_dbg_excScott Wood2013-05-142-4/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MSR_DE is not cleared on entry to the kernel, and we don't clear it explicitly outside of debug code. If we have MSR_DE set in prime_debug_regs(), and the new thread has events enabled in DBCR0 (e.g. ICMP is set in thread->dbsr0, even though it was cleared in the real DBCR0 when the thread got scheduled out), we'll end up taking a debug exception in the kernel when DBCR0 is loaded. DSRR0 will not point to an exception vector, and the kernel ends up hanging at kernel_dbg_exc. Fix this by always clearing MSR_DE when we load new debug state. Another observed source of kernel_dbg_exc hangs is with the branch taken event. If this event is active, but we take a non-debug trap (e.g. a TLB miss or an asynchronous interrupt) before the next branch. We end up taking a branch-taken debug exception on the initial branch instruction of the exception vector, but because the debug exception is DBSR_BT rather than DBSR_IC we branch to kernel_dbg_exc before even checking the DSRR0 address. Fix this by checking for DBSR_BT as well as DBSR_IC, which is what 32-bit does and what the comments suggest was intended in the 64-bit code as well. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Fix irq_set_affinity() return valuesAlexander Gordeev2013-05-144-4/+4
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Provide __bswapdi2David Woodhouse2013-05-143-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some versions of GCC apparently expect this to be provided by libgcc. Updates from Mikey to fix 32 bit version and adding "r" to registers. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/powernv: Fix starting of secondary CPUs on OPALv2 and v3Benjamin Herrenschmidt2013-05-141-6/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current code fails to handle kexec on OPALv2. This fixes it and adds code to improve the situation on OPALv3 where we can query the CPU status from the firmware and decide what to do based on that. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/powernv: Detect OPAL v3 API versionBenjamin Herrenschmidt2013-05-144-4/+13
| | | | | | | | | | | | | | | | | | | | | | | | Future firmwares will support that new version Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning againLi Zhong2013-05-143-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Saw this warning again, and this time from the ret_from_fork path. It seems we could clear the back chain earlier in copy_thread(), which could cover both path, and also fix potential lockdep usage in schedule_tail(), or exception occurred before we clear the back chain. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Make CONFIG_RTAS_PROC depend on CONFIG_PROC_FSMichael Ellerman2013-05-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are getting build errors with CONFIG_PROC_FS=n: arch/powerpc/kernel/rtas_flash.c In function 'rtas_flash_init': 745:33: error: unused variable 'f' [-Werror=unused-variable] But rtas_flash.c should not be built when CONFIG_PROC_FS=n, beacause all it does is provide a /proc interface to the RTAS flash routines. CONFIG_RTAS_FLASH already depends on CONFIG_RTAS_PROC, to indicate that it depends on the RTAS proc support, but CONFIG_RTAS_PROC does not depend on CONFIG_PROC_FS. So fix that. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Bring all threads online prior to migration/hibernationRobert Jennings2013-05-143-0/+137
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch brings online all threads which are present but not online prior to migration/hibernation. After migration/hibernation those threads are taken back offline. During migration/hibernation all online CPUs must call H_JOIN, this is required by the hypervisor. Without this patch, threads that are offline (H_CEDE'd) will not be woken to make the H_JOIN call and the OS will be deadlocked (all threads either JOIN'd or CEDE'd). Cc: <stable@kernel.org> Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/rtas_flash: Fix validate_flash buffer overflow issueVasant Hegde2013-05-141-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ibm,validate-flash-image RTAS call output buffer contains 150 - 200 bytes of data on latest system. Presently we have output buffer size as 64 bytes and we use sprintf to copy data from RTAS buffer to local buffer. This causes kernel oops (see below call trace). This patch increases local buffer size to 256 and also uses snprintf instead of sprintf to copy data from RTAS buffer. Kernel call trace : ------------------- Oops: Kernel access of bad area, sig: 11 [#1] SMP NR_CPUS=1024 NUMA pSeries Modules linked in: nfs fscache lockd auth_rpcgss nfs_acl sunrpc fuse loop dm_mod ipv6 ipv6_lib usb_storage ehea(X) sr_mod qlge ses cdrom enclosure st be2net sg ext3 jbd mbcache usbhid hid ohci_hcd ehci_hcd usbcore qla2xxx usb_common sd_mod crc_t10dif scsi_dh_hp_sw scsi_dh_rdac scsi_dh_alua scsi_dh_emc scsi_dh lpfc scsi_transport_fc scsi_tgt ipr(X) libata scsi_mod Supported: Yes NIP: 4520323031333130 LR: 4520323031333130 CTR: 0000000000000000 REGS: c0000001b91779b0 TRAP: 0400 Tainted: G X (3.0.13-0.27-ppc64) MSR: 8000000040009032 <EE,ME,IR,DR> CR: 44022488 XER: 20000018 TASK = c0000001bca1aba0[4736] 'cat' THREAD: c0000001b9174000 CPU: 36 GPR00: 4520323031333130 c0000001b9177c30 c000000000f87c98 000000000000009b GPR04: c0000001b9177c4a 000000000000000b 3520323031333130 2032303133313031 GPR08: 3133313031350a4d 000000000000009b 0000000000000000 c0000000003664a4 GPR12: 0000000022022448 c000000003ee6c00 0000000000000002 00000000100e8a90 GPR16: 00000000100cb9d8 0000000010093370 000000001001d310 0000000000000000 GPR20: 0000000000008000 00000000100fae60 000000000000005e 0000000000000000 GPR24: 0000000010129350 46573738302e3030 2046573738302e30 300a4d4720323031 GPR28: 333130313520554e 4b4e4f574e0a4d47 2032303133313031 3520323031333130 NIP [4520323031333130] 0x4520323031333130 LR [4520323031333130] 0x4520323031333130 Call Trace: [c0000001b9177c30] [4520323031333130] 0x4520323031333130 (unreliable) Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/kexec: Fix kexec when using VMX optimised memcpyAnton Blanchard2013-05-141-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b3f271e86e5a (powerpc: POWER7 optimised memcpy using VMX and enhanced prefetch) uses VMX when it is safe to do so (ie not in interrupt). It also looks at the task struct to decide if we have to save the current tasks' VMX state. kexec calls memcpy() at a point where the task struct may have been overwritten by the new kexec segments. If it has been overwritten then when memcpy -> enable_altivec looks up current->thread.regs->msr we get a cryptic oops or lockup. I also notice we aren't initialising thread_info->cpu, which means smp_processor_id is broken. Fix that too. Signed-off-by: Anton Blanchard <anton@samba.org> Cc: <stable@vger.kernel.org> # 3.6+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Fix build errors STRICT_MM_TYPECHECKSAneesh Kumar K.V2013-05-143-5/+5
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/mm: Use the correct mask value when looking at pgtable addressAneesh Kumar K.V2013-05-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Our pgtable are 2*sizeof(pte_t)*PTRS_PER_PTE which is PTE_FRAG_SIZE. Instead of depending on frag size, mask with PMD_MASKED_BITS. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: hard_irq_disable(): Call trace_hardirqs_off after disablingScott Wood2013-05-101-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | lockdep.c has this: /* * So we're supposed to get called after you mask local IRQs, * but for some reason the hardware doesn't quite think you did * a proper job. */ if (DEBUG_LOCKS_WARN_ON(!irqs_disabled())) return; Since irqs_disabled() is based on soft_enabled(), that (not just the hard EE bit) needs to be 0 before we call trace_hardirqs_off. Signed-off-by: Scott Wood <scottwood@freescale.com>
| * | | powerpc/powernv: Improve kexec reliabilityBenjamin Herrenschmidt2013-05-107-0/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We add a machine_shutdown hook that frees the OPAL interrupts (so they get masked at the source and don't fire while kexec'ing) and which triggers an IODA reset on all the PCIe host bridges which will have the effect of blocking all DMAs and subsequent PCIs interrupts. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc/powernv: Properly drop characters if console is closedBenjamin Herrenschmidt2013-05-081-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the firmware returns an error such as "closed" (or hardware error), we should drop characters. Currently we only do that when a firmware compatible with OPAL v2 APIs is detected, in the code that calls opal_console_write_buffer_space(), which didn't exist with OPAL v1 (or didn't work). However, when enabling early debug consoles, the flag indicating that v2 is supported isn't set yet, causing us, in case of errors or closed console, to spin forever. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | powerpc: Add an in memory udbg consoleAlistair Popple2013-05-085-0/+134
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a new udbg early debug console which utilises statically defined input and output buffers stored within the kernel BSS. It is primarily designed to assist with bring up of new hardware which may not have a working console but which has a method of reading/writing kernel memory. This version incorporates comments made by Ben H (thanks!). Changes from v1: - Add memory barriers. - Ensure updating of read/write positions is atomic. Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | | | Merge tag 'fixes-for-3.10-rc2-tag' of ↵Linus Torvalds2013-05-131-19/+14
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen Pull Xen/arm fixes from Stefano Stabellini: "This contains a couple of Xen on ARM initialization fixes and a patch to improve error handling" * tag 'fixes-for-3.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen: xen/arm: rename xen_secondary_init and run it on every online cpu xen/arm: do not handle VCPUOP_register_vcpu_info failures xen/arm: initialize pm functions later
| * | | | xen/arm: rename xen_secondary_init and run it on every online cpuStefano Stabellini2013-05-131-11/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename xen_secondary_init to xen_percpu_init. Run xen_percpu_init on the each online cpu, reuse the current on_each_cpu call. Merge xen_percpu_enable_events into xen_percpu_init. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
| * | | | xen/arm: do not handle VCPUOP_register_vcpu_info failuresStefano Stabellini2013-05-131-7/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We expect VCPUOP_register_vcpu_info to succeed, do not try to handle failures. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com>
| * | | | xen/arm: initialize pm functions laterStefano Stabellini2013-05-131-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we are running in dom0, we have to wait for the arch specific code to complete the initialization in order for us to successfully reset the power_off and pm_restart functions. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
* | | | | Merge branch 'parisc-for-3.10' of ↵Linus Torvalds2013-05-137-101/+194
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux Pull parisc update from Helge Deller: "The second round of parisc updates for 3.10 includes build fixes and enhancements to utilize irq stacks, fixes SMP races when updating PTE and TLB entries by proper locking and makes the search for the correct cross compiler more robust on Debian and Gentoo." * 'parisc-for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc: make default cross compiler search more robust (v3) parisc: fix SMP races when updating PTE and TLB entries in entry.S parisc: implement irq stacks - part 2 (v2)
| * | | | | parisc: make default cross compiler search more robust (v3)Helge Deller2013-05-131-12/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | People/distros vary how they prefix the toolchain name for 64bit builds. Rather than enforce one convention over another, add a for loop which does a search for all the general prefixes. For 64bit builds, we now search for (in order): hppa64-unknown-linux-gnu hppa64-linux-gnu hppa64-linux For 32bit builds, we look for: hppa-unknown-linux-gnu hppa-linux-gnu hppa-linux hppa2.0-unknown-linux-gnu hppa2.0-linux-gnu hppa2.0-linux hppa1.1-unknown-linux-gnu hppa1.1-linux-gnu hppa1.1-linux This patch was initiated by Mike Frysinger, with feedback from Jeroen Roovers, John David Anglin and Helge Deller. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Jeroen Roovers <jer@gentoo.org> Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de>
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