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2020-06-03padata: add basic support for multithreaded jobsDaniel Jordan1-3/+149
Sometimes the kernel doesn't take full advantage of system memory bandwidth, leading to a single CPU spending excessive time in initialization paths where the data scales with memory size. Multithreading naturally addresses this problem. Extend padata, a framework that handles many parallel yet singlethreaded jobs, to also handle multithreaded jobs by adding support for splitting up the work evenly, specifying a minimum amount of work that's appropriate for one helper thread to do, load balancing between helpers, and coordinating them. This is inspired by work from Pavel Tatashin and Steve Sistare. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Josh Triplett <josh@joshtriplett.org> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Robert Elliott <elliott@hpe.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/20200527173608.2885243-5-daniel.m.jordan@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03padata: allocate work structures for parallel jobs from a poolDaniel Jordan1-41/+77
padata allocates per-CPU, per-instance work structs for parallel jobs. A do_parallel call assigns a job to a sequence number and hashes the number to a CPU, where the job will eventually run using the corresponding work. This approach fit with how padata used to bind a job to each CPU round-robin, makes less sense after commit bfde23ce200e6 ("padata: unbind parallel jobs from specific CPUs") because a work isn't bound to a particular CPU anymore, and isn't needed at all for multithreaded jobs because they don't have sequence numbers. Replace the per-CPU works with a preallocated pool, which allows sharing them between existing padata users and the upcoming multithreaded user. The pool will also facilitate setting NUMA-aware concurrency limits with later users. The pool is sized according to the number of possible CPUs. With this limit, MAX_OBJ_NUM no longer makes sense, so remove it. If the global pool is exhausted, a parallel job is run in the current task instead to throttle a system trying to do too much in parallel. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Josh Triplett <josh@joshtriplett.org> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Robert Elliott <elliott@hpe.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/20200527173608.2885243-4-daniel.m.jordan@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03padata: initialize earlierDaniel Jordan1-9/+8
padata will soon initialize the system's struct pages in parallel, so it needs to be ready by page_alloc_init_late(). The error return from padata_driver_init() triggers an initcall warning, so add a warning to padata_init() to avoid silent failure. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Josh Triplett <josh@joshtriplett.org> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Robert Elliott <elliott@hpe.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/20200527173608.2885243-3-daniel.m.jordan@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03padata: remove exit routineDaniel Jordan1-6/+0
Patch series "padata: parallelize deferred page init", v3. Deferred struct page init is a bottleneck in kernel boot--the biggest for us and probably others. Optimizing it maximizes availability for large-memory systems and allows spinning up short-lived VMs as needed without having to leave them running. It also benefits bare metal machines hosting VMs that are sensitive to downtime. In projects such as VMM Fast Restart[1], where guest state is preserved across kexec reboot, it helps prevent application and network timeouts in the guests. So, multithread deferred init to take full advantage of system memory bandwidth. Extend padata, a framework that handles many parallel singlethreaded jobs, to handle multithreaded jobs as well by adding support for splitting up the work evenly, specifying a minimum amount of work that's appropriate for one helper thread to do, load balancing between helpers, and coordinating them. More documentation in patches 4 and 8. This series is the first step in a project to address other memory proportional bottlenecks in the kernel such as pmem struct page init, vfio page pinning, hugetlb fallocate, and munmap. Deferred page init doesn't require concurrency limits, resource control, or priority adjustments like these other users will because it happens during boot when the system is otherwise idle and waiting for page init to finish. This has been run on a variety of x86 systems and speeds up kernel boot by 4% to 49%, saving up to 1.6 out of 4 seconds. Patch 6 has more numbers. This patch (of 8): padata_driver_exit() is unnecessary because padata isn't built as a module and doesn't exit. padata's init routine will soon allocate memory, so getting rid of the exit function now avoids pointless code to free it. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Josh Triplett <josh@joshtriplett.org> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Robert Elliott <elliott@hpe.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/20200527173608.2885243-1-daniel.m.jordan@oracle.com Link: http://lkml.kernel.org/r/20200527173608.2885243-2-daniel.m.jordan@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-30padata: add separate cpuhp node for CPUHP_PADATA_DEADDaniel Jordan1-6/+8
Removing the pcrypt module triggers this: general protection fault, probably for non-canonical address 0xdead000000000122 CPU: 5 PID: 264 Comm: modprobe Not tainted 5.6.0+ #2 Hardware name: QEMU Standard PC RIP: 0010:__cpuhp_state_remove_instance+0xcc/0x120 Call Trace: padata_sysfs_release+0x74/0xce kobject_put+0x81/0xd0 padata_free+0x12/0x20 pcrypt_exit+0x43/0x8ee [pcrypt] padata instances wrongly use the same hlist node for the online and dead states, so __padata_free()'s second cpuhp remove call chokes on the node that the first poisoned. cpuhp multi-instance callbacks only walk forward in cpuhp_step->list and the same node is linked in both the online and dead lists, so the list corruption that results from padata_alloc() adding the node to a second list without removing it from the first doesn't cause problems as long as no instances are freed. Avoid the issue by giving each state its own node. Fixes: 894c9ef9780c ("padata: validate cpumask without removed CPU during offline") 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 Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-03-06crypto: pcrypt - simplify error handling in pcrypt_create_aead()Eric Biggers1-3/+4
Simplify the error handling in pcrypt_create_aead() by taking advantage of crypto_grab_aead() now handling an ERR_PTR() name and by taking advantage of crypto_drop_aead() now accepting (as a no-op) a spawn that hasn't been grabbed yet. This required also making padata_free_shell() accept a NULL argument. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-02-22padata: fix uninitialized return value in padata_replace()Daniel Jordan1-1/+1
According to Geert's report[0], kernel/padata.c: warning: 'err' may be used uninitialized in this function [-Wuninitialized]: => 539:2 Warning is seen only with older compilers on certain archs. The runtime effect is potentially returning garbage down the stack when padata's cpumasks are modified before any pcrypt requests have run. Simplest fix is to initialize err to the success value. [0] http://lkml.kernel.org/r/20200210135506.11536-1-geert@linux-m68k.org Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Fixes: bbefa1dd6a6d ("crypto: pcrypt - Avoid deadlock by using per-instance padata queues") 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>
2019-12-11padata: update documentationDaniel Jordan1-13/+22
Remove references to unused functions, standardize language, update to reflect new functionality, migrate to rst format, and fix all kernel-doc warnings. Fixes: 815613da6a67 ("kernel/padata.c: removed unused code") Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: linux-crypto@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11padata: remove reorder_objectsDaniel Jordan1-3/+0
reorder_objects is unused since the rework of padata's flushing, so remove it. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Eric Biggers <ebiggers@kernel.org> 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>
2019-12-11padata: remove cpumask change notifierDaniel Jordan1-51/+1
Since commit 63d3578892dc ("crypto: pcrypt - remove padata cpumask notifier") this feature is unused, so get rid of it. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Steffen Klassert <steffen.klassert@secunet.com> 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>
2019-12-11padata: always acquire cpu_hotplug_lock before pinst->lockDaniel Jordan1-2/+2
lockdep complains when padata's paths to update cpumasks via CPU hotplug and sysfs are both taken: # echo 0 > /sys/devices/system/cpu/cpu1/online # echo ff > /sys/kernel/pcrypt/pencrypt/parallel_cpumask ====================================================== WARNING: possible circular locking dependency detected 5.4.0-rc8-padata-cpuhp-v3+ #1 Not tainted ------------------------------------------------------ bash/205 is trying to acquire lock: ffffffff8286bcd0 (cpu_hotplug_lock.rw_sem){++++}, at: padata_set_cpumask+0x2b/0x120 but task is already holding lock: ffff8880001abfa0 (&pinst->lock){+.+.}, at: padata_set_cpumask+0x26/0x120 which lock already depends on the new lock. padata doesn't take cpu_hotplug_lock and pinst->lock in a consistent order. Which should be first? CPU hotplug calls into padata with cpu_hotplug_lock already held, so it should have priority. Fixes: 6751fb3c0e0c ("padata: Use get_online_cpus/put_online_cpus") Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Eric Biggers <ebiggers@kernel.org> 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>
2019-12-11padata: validate cpumask without removed CPU during offlineDaniel Jordan1-12/+18
Configuring an instance's parallel mask without any online CPUs... echo 2 > /sys/kernel/pcrypt/pencrypt/parallel_cpumask echo 0 > /sys/devices/system/cpu/cpu1/online ...makes tcrypt mode=215 crash like this: divide error: 0000 [#1] SMP PTI CPU: 4 PID: 283 Comm: modprobe Not tainted 5.4.0-rc8-padata-doc-v2+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191013_105130-anatol 04/01/2014 RIP: 0010:padata_do_parallel+0x114/0x300 Call Trace: pcrypt_aead_encrypt+0xc0/0xd0 [pcrypt] crypto_aead_encrypt+0x1f/0x30 do_mult_aead_op+0x4e/0xdf [tcrypt] test_mb_aead_speed.constprop.0.cold+0x226/0x564 [tcrypt] do_test+0x28c2/0x4d49 [tcrypt] tcrypt_mod_init+0x55/0x1000 [tcrypt] ... cpumask_weight() in padata_cpu_hash() returns 0 because the mask has no CPUs. The problem is __padata_remove_cpu() checks for valid masks too early and so doesn't mark the instance PADATA_INVALID as expected, which would have made padata_do_parallel() return error before doing the division. Fix by introducing a second padata CPU hotplug state before CPUHP_BRINGUP_CPU so that __padata_remove_cpu() sees the online mask without @cpu. No need for the second argument to padata_replace() since @cpu is now already missing from the online mask. Fixes: 33e54450683c ("padata: Handle empty padata cpumasks") Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11crypto: pcrypt - Avoid deadlock by using per-instance padata queuesHerbert Xu1-71/+165
If the pcrypt template is used multiple times in an algorithm, then a deadlock occurs because all pcrypt instances share the same padata_instance, which completes requests in the order submitted. That is, the inner pcrypt request waits for the outer pcrypt request while the outer request is already waiting for the inner. This patch fixes this by allocating a set of queues for each pcrypt instance instead of using two global queues. In order to maintain the existing user-space interface, the pinst structure remains global so any sysfs modifications will apply to every pcrypt instance. Note that when an update occurs we have to allocate memory for every pcrypt instance. Should one of the allocations fail we will abort the update without rolling back changes already made. The new per-instance data structure is called padata_shell and is essentially a wrapper around parallel_data. Reproducer: #include <linux/if_alg.h> #include <sys/socket.h> #include <unistd.h> int main() { struct sockaddr_alg addr = { .salg_type = "aead", .salg_name = "pcrypt(pcrypt(rfc4106-gcm-aesni))" }; int algfd, reqfd; char buf[32] = { 0 }; algfd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(algfd, (void *)&addr, sizeof(addr)); setsockopt(algfd, SOL_ALG, ALG_SET_KEY, buf, 20); reqfd = accept(algfd, 0, 0); write(reqfd, buf, 32); read(reqfd, buf, 16); } Reported-by: syzbot+56c7151cad94eec37c521f0e47d2eee53f9361c4@syzkaller.appspotmail.com Fixes: 5068c7a883d1 ("crypto: pcrypt - Add pcrypt crypto parallelization wrapper") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11padata: Remove unused padata_remove_cpuHerbert Xu1-35/+0
The function padata_remove_cpu was supposed to have been removed along with padata_add_cpu but somehow it remained behind. Let's kill it now as it doesn't even have a prototype anymore. Fixes: 815613da6a67 ("kernel/padata.c: removed unused code") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11padata: Remove broken queue flushingHerbert Xu1-31/+12
The function padata_flush_queues is fundamentally broken because it cannot force padata users to complete the request that is underway. IOW padata has to passively wait for the completion of any outstanding work. As it stands flushing is used in two places. Its use in padata_stop is simply unnecessary because nothing depends on the queues to be flushed afterwards. The other use in padata_replace is more substantial as we depend on it to free the old pd structure. This patch instead uses the pd->refcnt to dynamically free the pd structure once all requests are complete. Fixes: 2b73b07ab8a4 ("padata: Flush the padata queues actively") Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-13padata: remove cpu_index from the parallel_queueDaniel Jordan1-11/+2
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 Jordan1-53/+65
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 Jordan1-10/+18
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 Jordan1-8/+9
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 Jordan1-7/+20
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 Jordan1-9/+15
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 Jordan1-1/+1
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 Jordan1-20/+3
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 Xu1-79/+18
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 Jordan1-0/+12
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 Brown1-1/+2
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 King1-1/+1
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 Cheong1-0/+1
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 Cook1-3/+3
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 Krause1-1/+19
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 Krause1-1/+42
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 Krause1-1/+7
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 Siewior1-5/+6
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 Gleixner1-16/+16
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. Donenfeld1-9/+4
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. Donenfeld1-1/+1
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. Donenfeld1-2/+3
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 Klauser1-4/+0
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 Siewior1-38/+50
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 Bergmann1-37/+37
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 Cochran1-64/+0
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 Heo1-8/+3
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 Krause1-1/+1
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 Krause1-5/+4
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 Weinberger1-6/+6
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 Gang1-16/+4
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 Wei1-3/+2
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 Klassert1-0/+3
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 Klassert1-4/+4
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 Klassert1-0/+2
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>