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2019-09-13padata: remove cpu_index from the parallel_queueDaniel Jordan
With the removal of the ENODATA case from padata_get_next, the cpu_index field is no longer useful, so it can go away. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-13padata: unbind parallel jobs from specific CPUsDaniel Jordan
Padata binds the parallel part of a job to a single CPU and round-robins over all CPUs in the system for each successive job. Though the serial parts rely on per-CPU queues for correct ordering, they're not necessary for parallel work, and it improves performance to run the job locally on NUMA machines and let the scheduler pick the CPU within a node on a busy system. So, make the parallel workqueue unbound. Update the parallel workqueue's cpumask when the instance's parallel cpumask changes. Now that parallel jobs no longer run on max_active=1 workqueues, two or more parallel works that hash to the same CPU may run simultaneously, finish out of order, and so be serialized out of order. Prevent this by keeping the works sorted on the reorder list by sequence number and checking that in the reordering logic. padata_get_next becomes padata_find_next so it can be reused for the end of padata_reorder, where it's used to avoid uselessly queueing work when the next job by sequence number isn't finished yet but a later job that hashed to the same CPU has. The ENODATA case in padata_find_next no longer makes sense because parallel jobs aren't bound to specific CPUs. The EINPROGRESS case takes care of the scenario where a parallel job is potentially running on the same CPU as padata_find_next, and with only one error code left, just use NULL instead. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Tejun Heo <tj@kernel.org> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-13padata: use separate workqueues for parallel and serial workDaniel Jordan
padata currently uses one per-CPU workqueue per instance for all work. Prepare for running parallel jobs on an unbound workqueue by introducing dedicated workqueues for parallel and serial work. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-13padata, pcrypt: take CPU hotplug lock internally in padata_alloc_possibleDaniel Jordan
With pcrypt's cpumask no longer used, take the CPU hotplug lock inside padata_alloc_possible. Useful later in the series for avoiding nested acquisition of the CPU hotplug lock in padata when padata_alloc_possible is allocating an unbound workqueue. Without this patch, this nested acquisition would happen later in the series: pcrypt_init_padata get_online_cpus alloc_padata_possible alloc_padata alloc_workqueue(WQ_UNBOUND) // later in the series alloc_and_link_pwqs apply_wqattrs_lock get_online_cpus // recursive rwsem acquisition Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-13padata: make padata_do_parallel find alternate callback CPUDaniel Jordan
padata_do_parallel currently returns -EINVAL if the callback CPU isn't in the callback cpumask. pcrypt tries to prevent this situation by keeping its own callback cpumask in sync with padata's and checks that the callback CPU it passes to padata is valid. Make padata handle this instead. padata_do_parallel now takes a pointer to the callback CPU and updates it for the caller if an alternate CPU is used. Overall behavior in terms of which callback CPUs are chosen stays the same. Prepares for removal of the padata cpumask notifier in pcrypt, which will fix a lockdep complaint about nested acquisition of the CPU hotplug lock later in the series. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-13padata: allocate workqueue internallyDaniel Jordan
Move workqueue allocation inside of padata to prepare for further changes to how padata uses workqueues. Guarantees the workqueue is created with max_active=1, which padata relies on to work correctly. No functional change. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: linux-crypto@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-09padata: initialize pd->cpu with effective cpumaskDaniel Jordan
Exercising CPU hotplug on a 5.2 kernel with recent padata fixes from cryptodev-2.6.git in an 8-CPU kvm guest... # modprobe tcrypt alg="pcrypt(rfc4106(gcm(aes)))" type=3 # echo 0 > /sys/devices/system/cpu/cpu1/online # echo c > /sys/kernel/pcrypt/pencrypt/parallel_cpumask # modprobe tcrypt mode=215 ...caused the following crash: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 2 PID: 134 Comm: kworker/2:2 Not tainted 5.2.0-padata-base+ #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-<snip> Workqueue: pencrypt padata_parallel_worker RIP: 0010:padata_reorder+0xcb/0x180 ... Call Trace: padata_do_serial+0x57/0x60 pcrypt_aead_enc+0x3a/0x50 [pcrypt] padata_parallel_worker+0x9b/0xe0 process_one_work+0x1b5/0x3f0 worker_thread+0x4a/0x3c0 ... In padata_alloc_pd, pd->cpu is set using the user-supplied cpumask instead of the effective cpumask, and in this case cpumask_first picked an offline CPU. The offline CPU's reorder->list.next is NULL in padata_reorder because the list wasn't initialized in padata_init_pqueues, which only operates on CPUs in the effective mask. Fix by using the effective mask in padata_alloc_pd. Fixes: 6fc4dbcf0276 ("padata: Replace delayed timer with immediate workqueue in padata_reorder") Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-07-27padata: purge get_cpu and reorder_via_wq from padata_do_serialDaniel Jordan
With the removal of the padata timer, padata_do_serial no longer needs special CPU handling, so remove it. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-07-27padata: Replace delayed timer with immediate workqueue in padata_reorderHerbert Xu
The function padata_reorder will use a timer when it cannot progress while completed jobs are outstanding (pd->reorder_objects > 0). This is suboptimal as if we do end up using the timer then it would have introduced a gratuitous delay of one second. In fact we can easily distinguish between whether completed jobs are outstanding and whether we can make progress. All we have to do is look at the next pqueue list. This patch does that by replacing pd->processed with pd->cpu so that the next pqueue is more accessible. A work queue is used instead of the original try_again to avoid hogging the CPU. Note that we don't bother removing the work queue in padata_flush_queues because the whole premise is broken. You cannot flush async crypto requests so it makes no sense to even try. A subsequent patch will fix it by replacing it with a ref counting scheme. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-07-18padata: use smp_mb in padata_reorder to avoid orphaned padata jobsDaniel Jordan
Testing padata with the tcrypt module on a 5.2 kernel... # modprobe tcrypt alg="pcrypt(rfc4106(gcm(aes)))" type=3 # modprobe tcrypt mode=211 sec=1 ...produces this splat: INFO: task modprobe:10075 blocked for more than 120 seconds. Not tainted 5.2.0-base+ #16 modprobe D 0 10075 10064 0x80004080 Call Trace: ? __schedule+0x4dd/0x610 ? ring_buffer_unlock_commit+0x23/0x100 schedule+0x6c/0x90 schedule_timeout+0x3b/0x320 ? trace_buffer_unlock_commit_regs+0x4f/0x1f0 wait_for_common+0x160/0x1a0 ? wake_up_q+0x80/0x80 { crypto_wait_req } # entries in braces added by hand { do_one_aead_op } { test_aead_jiffies } test_aead_speed.constprop.17+0x681/0xf30 [tcrypt] do_test+0x4053/0x6a2b [tcrypt] ? 0xffffffffa00f4000 tcrypt_mod_init+0x50/0x1000 [tcrypt] ... The second modprobe command never finishes because in padata_reorder, CPU0's load of reorder_objects is executed before the unlocking store in spin_unlock_bh(pd->lock), causing CPU0 to miss CPU1's increment: CPU0 CPU1 padata_reorder padata_do_serial LOAD reorder_objects // 0 INC reorder_objects // 1 padata_reorder TRYLOCK pd->lock // failed UNLOCK pd->lock CPU0 deletes the timer before returning from padata_reorder and since no other job is submitted to padata, modprobe waits indefinitely. Add a pair of full barriers to guarantee proper ordering: CPU0 CPU1 padata_reorder padata_do_serial UNLOCK pd->lock smp_mb() LOAD reorder_objects INC reorder_objects smp_mb__after_atomic() padata_reorder TRYLOCK pd->lock smp_mb__after_atomic is needed so the read part of the trylock operation comes after the INC, as Andrea points out. Thanks also to Andrea for help with writing a litmus test. Fixes: 16295bec6398 ("padata: Generic parallelization/serialization interface") Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: <stable@vger.kernel.org> Cc: Andrea Parri <andrea.parri@amarulasolutions.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: linux-arch@vger.kernel.org Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-25padata: Replace padata_attr_type default_attrs field with groupsKimberly Brown
The kobj_type default_attrs field is being replaced by the default_groups field. Replace padata_attr_type's default_attrs field with default_groups and use the ATTRIBUTE_GROUPS macro to create padata_default_groups. This patch was tested by loading the pcrypt module and verifying that the sysfs files for the attributes in the default groups were created. Signed-off-by: Kimberly Brown <kimbrownkd@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-16padata: clean an indentation issue, remove extraneous spaceColin Ian King
Trivial fix to clean up an indentation issue Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-05padata: add SPDX identifierCheah Kok Cheong
Add SPDX license identifier according to the type of license text found in the file. Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Cheah Kok Cheong <thrust73@gmail.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-21treewide: setup_timer() -> timer_setup()Kees Cook
This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
2017-10-07padata: ensure padata_do_serial() runs on the correct CPUMathias Krause
If the algorithm we're parallelizing is asynchronous we might change CPUs between padata_do_parallel() and padata_do_serial(). However, we don't expect this to happen as we need to enqueue the padata object into the per-cpu reorder queue we took it from, i.e. the same-cpu's parallel queue. Ensure we're not switching CPUs for a given padata object by tracking the CPU within the padata object. If the serial callback gets called on the wrong CPU, defer invoking padata_reorder() via a kernel worker on the CPU we're expected to run on. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-10-07padata: ensure the reorder timer callback runs on the correct CPUMathias Krause
The reorder timer function runs on the CPU where the timer interrupt was handled which is not necessarily one of the CPUs of the 'pcpu' CPU mask set. Ensure the padata_reorder() callback runs on the correct CPU, which is one in the 'pcpu' CPU mask set and, preferrably, the next expected one. Do so by comparing the current CPU with the expected target CPU. If they match, call padata_reorder() right away. If they differ, schedule a work item on the target CPU that does the padata_reorder() call for us. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-10-07padata: set cpu_index of unused CPUs to -1Mathias Krause
The parallel queue per-cpu data structure gets initialized only for CPUs in the 'pcpu' CPU mask set. This is not sufficient as the reorder timer may run on a different CPU and might wrongly decide it's the target CPU for the next reorder item as per-cpu memory gets memset(0) and we might be waiting for the first CPU in cpumask.pcpu, i.e. cpu_index 0. Make the '__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index' compare in padata_get_next() fail in this case by initializing the cpu_index member of all per-cpu parallel queues. Use -1 for unused ones. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-05-26padata: Avoid nested calls to cpus_read_lock() in pcrypt_init_padata()Sebastian Andrzej Siewior
pcrypt_init_padata() cpus_read_lock() padata_alloc_possible() padata_alloc() cpus_read_lock() The nested call to cpus_read_lock() works with the current implementation, but prevents the conversion to a percpu rwsem. The other caller of padata_alloc_possible() is pcrypt_init_padata() which calls from a cpus_read_lock() protected region as well. Remove the cpus_read_lock() call in padata_alloc() and document the calling convention. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-crypto@vger.kernel.org Link: http://lkml.kernel.org/r/20170524081547.571278910@linutronix.de
2017-05-26padata: Make padata_alloc() staticThomas Gleixner
No users outside of padata.c Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-crypto@vger.kernel.org Link: http://lkml.kernel.org/r/20170524081547.491457256@linutronix.de
2017-04-21padata: get_next is never NULLJason A. Donenfeld
Per Dan's static checker warning, the code that returns NULL was removed in 2010, so this patch updates the comments and fixes the code assumptions. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-04-10padata: free correct variableJason A. Donenfeld
The author meant to free the variable that was just allocated, instead of the one that failed to be allocated, but made a simple typo. This patch rectifies that. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-03-24padata: avoid race in reorderingJason A. Donenfeld
Under extremely heavy uses of padata, crashes occur, and with list debugging turned on, this happens instead: [87487.298728] WARNING: CPU: 1 PID: 882 at lib/list_debug.c:33 __list_add+0xae/0x130 [87487.301868] list_add corruption. prev->next should be next (ffffb17abfc043d0), but was ffff8dba70872c80. (prev=ffff8dba70872b00). [87487.339011] [<ffffffff9a53d075>] dump_stack+0x68/0xa3 [87487.342198] [<ffffffff99e119a1>] ? console_unlock+0x281/0x6d0 [87487.345364] [<ffffffff99d6b91f>] __warn+0xff/0x140 [87487.348513] [<ffffffff99d6b9aa>] warn_slowpath_fmt+0x4a/0x50 [87487.351659] [<ffffffff9a58b5de>] __list_add+0xae/0x130 [87487.354772] [<ffffffff9add5094>] ? _raw_spin_lock+0x64/0x70 [87487.357915] [<ffffffff99eefd66>] padata_reorder+0x1e6/0x420 [87487.361084] [<ffffffff99ef0055>] padata_do_serial+0xa5/0x120 padata_reorder calls list_add_tail with the list to which its adding locked, which seems correct: spin_lock(&squeue->serial.lock); list_add_tail(&padata->list, &squeue->serial.list); spin_unlock(&squeue->serial.lock); This therefore leaves only place where such inconsistency could occur: if padata->list is added at the same time on two different threads. This pdata pointer comes from the function call to padata_get_next(pd), which has in it the following block: next_queue = per_cpu_ptr(pd->pqueue, cpu); padata = NULL; reorder = &next_queue->reorder; if (!list_empty(&reorder->list)) { padata = list_entry(reorder->list.next, struct padata_priv, list); spin_lock(&reorder->lock); list_del_init(&padata->list); atomic_dec(&pd->reorder_objects); spin_unlock(&reorder->lock); pd->processed++; goto out; } out: return padata; I strongly suspect that the problem here is that two threads can race on reorder list. Even though the deletion is locked, call to list_entry is not locked, which means it's feasible that two threads pick up the same padata object and subsequently call list_add_tail on them at the same time. The fix is thus be hoist that lock outside of that block. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-10-25padata: Remove unused but set variablesTobias Klauser
Remove the unused but set variable pinst in padata_parallel_worker to fix the following warning when building with 'W=1': kernel/padata.c: In function ‘padata_parallel_worker’: kernel/padata.c:68:26: warning: variable ‘pinst’ set but not used [-Wunused-but-set-variable] Also remove the now unused variable pd which is only used to set pinst. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-09-19padata: Convert to hotplug state machineSebastian Andrzej Siewior
Install the callbacks via the state machine. CPU-hotplug multinstance support is used with the nocalls() version. Maybe parts of padata_alloc() could be moved into the online callback so that we could invoke ->startup callback for instance and drop get_online_cpus(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-crypto@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160906170457.32393-14-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-05-19kernel/padata.c: hide unused functionsArnd Bergmann
A recent cleanup removed some exported functions that were not used anywhere, which in turn exposed the fact that some other functions in the same file are only used in some configurations. We now get a warning about them when CONFIG_HOTPLUG_CPU is disabled: kernel/padata.c:670:12: error: '__padata_remove_cpu' defined but not used [-Werror=unused-function] static int __padata_remove_cpu(struct padata_instance *pinst, int cpu) ^~~~~~~~~~~~~~~~~~~ kernel/padata.c:650:12: error: '__padata_add_cpu' defined but not used [-Werror=unused-function] static int __padata_add_cpu(struct padata_instance *pinst, int cpu) This rearranges the code so the __padata_remove_cpu/__padata_add_cpu functions are within the #ifdef that protects the code that calls them. [akpm@linux-foundation.org: coding-style fixes] Fixes: 4ba6d78c671e ("kernel/padata.c: removed unused code") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Richard Cochran <rcochran@linutronix.de> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-19kernel/padata.c: removed unused codeRichard Cochran
By accident I stumbled across code that has never been used. This driver has EXPORT_SYMBOL functions, and the only user of the code is pcrypt.c, but this only uses a subset of the exported symbols. According to 'git log -G', the functions, padata_set_cpumasks, padata_add_cpu, and padata_remove_cpu have never been used since they were first introduced. This patch removes the unused code. On one 64 bit build, with CRYPTO_PCRYPT built in, the text is more than 4k smaller. kbuild_hp> size $KBUILD_OUTPUT/vmlinux text data bss dec hex filename 10566658 4678360 1122304 16367322 f9beda vmlinux 10561984 4678360 1122304 16362648 f9ac98 vmlinux On another config, 32 bit, the saving is about 0.5k bytes. kbuild_hp-x86> size $KBUILD_OUTPUT/vmlinux 6012005 2409513 2785280 11206798 ab008e vmlinux 6011491 2409513 2785280 11206284 aafe8c vmlinux Signed-off-by: Richard Cochran <rcochran@linutronix.de> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13padata: use %*pb[l] to print bitmaps including cpumasks and nodemasksTejun Heo
printk and friends can now format bitmaps using '%*pb[l]'. cpumask and nodemask also provide cpumask_pr_args() and nodemask_pr_args() respectively which can be used to generate the two printf arguments necessary to format the specified cpu/nodemask. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-12-05padata: Fix wrong usage of rcu_dereference()Mathias Krause
A kernel with enabled lockdep complains about the wrong usage of rcu_dereference() under a rcu_read_lock_bh() protected region. =============================== [ INFO: suspicious RCU usage. ] 3.13.0-rc1+ #126 Not tainted ------------------------------- linux/kernel/padata.c:115 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 1 lock held by cryptomgr_test/153: #0: (rcu_read_lock_bh){.+....}, at: [<ffffffff8115c235>] padata_do_parallel+0x5/0x270 Fix that by using rcu_dereference_bh() instead. Signed-off-by: Mathias Krause <minipli@googlemail.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-10-30padata: make the sequence counter an atomic_tMathias Krause
Using a spinlock to atomically increase a counter sounds wrong -- we've atomic_t for this! Also move 'seq_nr' to a different cache line than 'lock' to reduce cache line trashing. This has the nice side effect of decreasing the size of struct parallel_data from 192 to 128 bytes for a x86-64 build, e.g. occupying only two instead of three cache lines. Those changes results in a 5% performance increase on an IPsec test run using pcrypt. Btw. the seq_lock spinlock was never explicitly initialized -- one more reason to get rid of it. Signed-off-by: Mathias Krause <mathias.krause@secunet.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-08-29padata - Register hotcpu notifier after initializationRichard Weinberger
padata_cpu_callback() takes pinst->lock, to avoid taking an uninitialized lock, register the notifier after it's initialization. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-08-29padata - share code between CPU_ONLINE and CPU_DOWN_FAILED, same to ↵Chen Gang
CPU_DOWN_PREPARE and CPU_UP_CANCELED Share code between CPU_ONLINE and CPU_DOWN_FAILED, same to CPU_DOWN_PREPARE and CPU_UP_CANCELED. It will fix 2 bugs: "not check the return value of __padata_remove_cpu() and __padata_add_cpu()". "need add 'break' between CPU_UP_CANCELED and CPU_DOWN_FAILED". Signed-off-by: Chen Gang <gang.chen@asianux.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-12-06padata: use __this_cpu_read per-cpu helperShan Wei
For bottom halves off, __this_cpu_read is better. Signed-off-by: Shan Wei <davidshan@tencent.com> Reviewed-by: Christoph Lameter <cl@linux.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-29padata: Fix cpu hotplugSteffen Klassert
We don't remove the cpu that went offline from our cpumasks on cpu hotplug. This got lost somewhere along the line, so restore it. This fixes a hang of the padata instance on cpu hotplug. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-29padata: Use the online cpumask as the defaultSteffen Klassert
We use the active cpumask to determine the superset of cpus to use for parallelization. However, the active cpumask is for internal usage of the scheduler and therefore not the appropriate cpumask for these purposes. So use the online cpumask instead. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-29padata: Add a reference to the api documentationSteffen Klassert
Add a reference to the padata api documentation at Documentation/padata.txt Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-14padata: Fix race on sequence number wrapSteffen Klassert
When padata_do_parallel() is called from multiple cpus for the same padata instance, we can get object reordering on sequence number wrap because testing for sequence number wrap and reseting the sequence number must happen atomically but is implemented with two atomic operations. This patch fixes this by converting the sequence number from atomic_t to an unsigned int and protect the access with a spin_lock. As a side effect, we get rid of the sequence number wrap handling because the seqence number wraps back to null now without the need to do anything. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-14padata: Fix race in the serialization pathSteffen Klassert
When a padata object is queued to the serialization queue, another cpu might process and free the padata object. So don't dereference it after queueing to the serialization queue. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-10-31kernel: Map most files to use export.h instead of module.hPaul Gortmaker
The changed files were only including linux/module.h for the EXPORT_SYMBOL infrastructure, and nothing else. Revector them onto the isolated export header for faster compile times. Nothing to see here but a whole lot of instances of: -#include <linux/module.h> +#include <linux/export.h> This commit is only changing the kernel dir; next targets will probably be mm, fs, the arch dirs, etc. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2010-08-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (39 commits) random: Reorder struct entropy_store to remove padding on 64bits padata: update API documentation padata: Remove padata_get_cpumask crypto: pcrypt - Update pcrypt cpumask according to the padata cpumask notifier crypto: pcrypt - Rename pcrypt_instance padata: Pass the padata cpumasks to the cpumask_change_notifier chain padata: Rearrange set_cpumask functions padata: Rename padata_alloc functions crypto: pcrypt - Dont calulate a callback cpu on empty callback cpumask padata: Check for valid cpumasks padata: Allocate cpumask dependend recources in any case padata: Fix cpu index counting crypto: geode_aes - Convert pci_table entries to PCI_VDEVICE (if PCI_ANY_ID is used) pcrypt: Added sysfs interface to pcrypt padata: Added sysfs primitives to padata subsystem padata: Make two separate cpumasks padata: update documentation padata: simplify serialization mechanism padata: make padata_do_parallel to return zero on success padata: Handle empty padata cpumasks ...
2010-07-31padata: Remove padata_get_cpumaskSteffen Klassert
A function that copies the padata cpumasks to a user buffer is a bit error prone. The cpumask can change any time so we can't be sure to have the right cpumask when using this function. A user who is interested in the padata cpumasks should register to the padata cpumask notifier chain instead. Users of padata_get_cpumask are already updated, so we can remove it. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-31padata: Pass the padata cpumasks to the cpumask_change_notifier chainSteffen Klassert
We pass a pointer to the new padata cpumasks to the cpumask_change_notifier chain. So users can access the cpumasks without the need of an extra padata_get_cpumask function. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-31padata: Rearrange set_cpumask functionsSteffen Klassert
padata_set_cpumask needs to be protected by a lock. We make __padata_set_cpumasks unlocked and static. So this function can be used by the exported and locked padata_set_cpumask and padata_set_cpumasks functions. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-31padata: Rename padata_alloc functionsSteffen Klassert
We rename padata_alloc to padata_alloc_possible because this function allocates a padata_instance and uses the cpu_possible mask for parallel and serial workers. Also we rename __padata_alloc to padata_alloc to avoid to export underlined functions. Underlined functions are considered to be private to padata. Users are updated accordingly. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-26padata: Check for valid cpumasksSteffen Klassert
Now that we allow to change the cpumasks from userspace, we have to check for valid cpumasks in padata_do_parallel. This patch adds the necessary check. This fixes a division by zero crash if the parallel cpumask contains no active cpu. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-26padata: Allocate cpumask dependend recources in any caseSteffen Klassert
The cpumask separation work assumes the cpumask dependend recources present regardless of valid or invalid cpumasks. With this patch we allocate the cpumask dependend recources in any case. This fixes two NULL pointer dereference crashes in padata_replace and in padata_get_cpumask. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-26padata: Fix cpu index countingSteffen Klassert
The counting of the cpu index got lost with a recent commit. This patch restores it. This fixes a hang of the parallel worker threads on cpu hotplug. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-19padata: Added sysfs primitives to padata subsystemDan Kruchinin
Added sysfs primitives to padata subsystem. Now API user may embedded kobject each padata instance contains into any sysfs hierarchy. For now padata sysfs interface provides only two objects: serial_cpumask [RW] - cpumask for serial workers parallel_cpumask [RW] - cpumask for parallel workers Signed-off-by: Dan Kruchinin <dkruchinin@acm.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-19padata: Make two separate cpumasksDan Kruchinin
The aim of this patch is to make two separate cpumasks for padata parallel and serial workers respectively. It allows user to make more thin and sophisticated configurations of padata framework. For example user may bind parallel and serial workers to non-intersecting CPU groups to gain better performance. Also each padata instance has notifiers chain for its cpumasks now. If either parallel or serial or both masks were changed all interested subsystems will get notification about that. It's especially useful if padata user uses algorithm for callback CPU selection according to serial cpumask. Signed-off-by: Dan Kruchinin <dkruchinin@acm.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14padata: simplify serialization mechanismSteffen Klassert
We count the number of processed objects on a percpu basis, so we need to go through all the percpu reorder queues to calculate the sequence number of the next object that needs serialization. This patch changes this to count the number of processed objects global. So we can calculate the sequence number and the percpu reorder queue of the next object that needs serialization without searching through the percpu reorder queues. This avoids some accesses to memory of foreign cpus. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>