summaryrefslogtreecommitdiffstats
path: root/arch/sparc/kernel/smp_64.c
Commit message (Collapse)AuthorAgeFilesLines
* sparc64: remove mm_cpumask clearing to fix kthread_use_mm raceNicholas Piggin2020-11-101-51/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit bafb056ce27940c9994ea905336aa8f27b4f7275 ] The de facto (and apparently uncommented) standard for using an mm had, thanks to this code in sparc if nothing else, been that you must have a reference on mm_users *and that reference must have been obtained with mmget()*, i.e., from a thread with a reference to mm_users that had used the mm. The introduction of mmget_not_zero() in commit d2005e3f41d4 ("userfaultfd: don't pin the user memory in userfaultfd_file_create()") allowed mm_count holders to aoperate on user mappings asynchronously from the actual threads using the mm, but they were not to load those mappings into their TLB (i.e., walking vmas and page tables is okay, kthread_use_mm() is not). io_uring 2b188cc1bb857 ("Add io_uring IO interface") added code which does a kthread_use_mm() from a mmget_not_zero() refcount. The problem with this is code which previously assumed mm == current->mm and mm->mm_users == 1 implies the mm will remain single-threaded at least until this thread creates another mm_users reference, has now broken. arch/sparc/kernel/smp_64.c: if (atomic_read(&mm->mm_users) == 1) { cpumask_copy(mm_cpumask(mm), cpumask_of(cpu)); goto local_flush_and_out; } vs fs/io_uring.c if (unlikely(!(ctx->flags & IORING_SETUP_SQPOLL) || !mmget_not_zero(ctx->sqo_mm))) return -EFAULT; kthread_use_mm(ctx->sqo_mm); mmget_not_zero() could come in right after the mm_users == 1 test, then kthread_use_mm() which sets its CPU in the mm_cpumask. That update could be lost if cpumask_copy() occurs afterward. I propose we fix this by allowing mmget_not_zero() to be a first-class reference, and not have this obscure undocumented and unchecked restriction. The basic fix for sparc64 is to remove its mm_cpumask clearing code. The optimisation could be effectively restored by sending IPIs to mm_cpumask members and having them remove themselves from mm_cpumask. This is more tricky so I leave it as an exercise for someone with a sparc64 SMP. powerpc has a (currently similarly broken) example. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200914045219.3736466-4-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
* sparc64: Migrate hvcons irq to panicked cpuVijay Kumar2017-10-211-1/+5
| | | | | | | | | | | | | [ Upstream commit 7dd4fcf5b70694dc961eb6b954673e4fc9730dbd ] On panic, all other CPUs are stopped except the one which had hit panic. To keep console alive, we need to migrate hvcons irq to panicked CPU. Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sparc64: Measure receiver forward progress to avoid send mondo timeoutJane Chu2017-08-111-70/+115
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 9d53caec84c7c5700e7c1ed744ea584fff55f9ac ] A large sun4v SPARC system may have moments of intensive xcall activities, usually caused by unmapping many pages on many CPUs concurrently. This can flood receivers with CPU mondo interrupts for an extended period, causing some unlucky senders to hit send-mondo timeout. This problem gets worse as cpu count increases because sometimes mappings must be invalidated on all CPUs, and sometimes all CPUs may gang up on a single CPU. But a busy system is not a broken system. In the above scenario, as long as the receiver is making forward progress processing mondo interrupts, the sender should continue to retry. This patch implements the receiver's forward progress meter by introducing a per cpu counter 'cpu_mondo_counter[cpu]' where 'cpu' is in the range of 0..NR_CPUS. The receiver increments its counter as soon as it receives a mondo and the sender tracks the receiver's counter. If the receiver has stopped making forward progress when the retry limit is reached, the sender declares send-mondo-timeout and panic; otherwise, the receiver is allowed to keep making forward progress. In addition, it's been observed that PCIe hotplug events generate Correctable Errors that are handled by hypervisor and then OS. Hypervisor 'borrows' a guest cpu strand briefly to provide the service. If the cpu strand is simultaneously the only cpu targeted by a mondo, it may not be available for the mondo in 20msec, causing SUN4V mondo timeout. It appears that 1 second is the agreed wait time between hypervisor and guest OS, this patch makes the adjustment. Orabug: 25476541 Orabug: 26417466 Signed-off-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Steve Sistare <steven.sistare@oracle.com> Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com> Reviewed-by: Rob Gardner <rob.gardner@oracle.com> Reviewed-by: Thomas Tai <thomas.tai@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sparc64: delete old wrap codePavel Tatashin2017-06-141-31/+0
| | | | | | | | | | | | | | [ Upstream commit 0197e41ce70511dc3b71f7fefa1a676e2b5cd60b ] The old method that is using xcall and softint to get new context id is deleted, as it is replaced by a method of using per_cpu_secondary_mm without xcall to perform the context wrap. Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sparc64: Setup a scheduling domain for highest level cache.Atish Patra2016-10-241-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | Individual scheduler domain should consist different hierarchy consisting of cores sharing similar property. Currently, no scheduler domain is defined separately for the cores that shares the last level cache. As a result, the scheduler fails to take advantage of cache locality while migrating tasks during load balancing. Here are the cpu masks currently present for sparc that are/can be used in scheduler domain construction. cpu_core_map : set based on the cores that shares l1 cache. core_core_sib_map : is set based on the socket id. The prior SPARC notion of socket was defined as highest level of shared cache. However, the MD record on T7 platforms now describes the CPUs that share the physical socket and this is no longer tied to shared cache. That's why a separate cpu mask needs to be created that truly represent highest level of shared cache for all platforms. Signed-off-by: Atish Patra <atish.patra@oracle.com> Reviewed-by: Chris Hyser <chris.hyser@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Fix cpu_possible_mask if nr_cpus is setAtish Patra2016-09-281-0/+14
| | | | | | | | | | | | | | | | | | If kernel boot parameter nr_cpus is set, it should define the number of CPUs that can ever be available in the system i.e. cpu_possible_mask. setup_nr_cpu_ids() overrides the nr_cpu_ids based on the cpu_possible_mask during kernel initialization. If cpu_possible_mask is not set based on the nr_cpus value, earlier part of the kernel would be initialized using nr_cpus value leading to a kernel crash. Set cpu_possible_mask based on nr_cpus value. Thus setup_nr_cpu_ids() becomes redundant and does not corrupt nr_cpu_ids value. Signed-off-by: Atish Patra <atish.patra@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Vijay Kumar <vijay.ac.kumar@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* arch/hotplug: Call into idle with a proper stateThomas Gleixner2016-03-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Let the non boot cpus call into idle with the corresponding hotplug state, so the hotplug core can handle the further bringup. That's a first step to convert the boot side of the hotplugged cpus to do all the synchronization with the other side through the state machine. For now it'll only start the hotplug thread and kick the full bringup of the cpu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Rik van Riel <riel@redhat.com> Cc: Rafael Wysocki <rafael.j.wysocki@intel.com> Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* sparc64: Setup sysfs to mark LDOM sockets, cores and threads correctlychris hyser2015-04-221-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5f4826a362405748bbf73957027b77993e61e1af Author: chris hyser <chris.hyser@oracle.com> Date: Tue Apr 21 10:31:38 2015 -0400 sparc64: Setup sysfs to mark LDOM sockets, cores and threads correctly The current sparc kernel has no representation for sockets though tools like lscpu can pull this from sysfs. This patch walks the machine description cache and socket hierarchy and marks sockets as well as cores and threads such that a representative sysfs is created by drivers/base/topology.c. Before this patch: $ lscpu Architecture: sparc64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Big Endian CPU(s): 1024 On-line CPU(s) list: 0-1023 Thread(s) per core: 8 Core(s) per socket: 1 <--- wrong Socket(s): 128 <--- wrong NUMA node(s): 4 NUMA node0 CPU(s): 0-255 NUMA node1 CPU(s): 256-511 NUMA node2 CPU(s): 512-767 NUMA node3 CPU(s): 768-1023 After this patch: $ lscpu Architecture: sparc64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Big Endian CPU(s): 1024 On-line CPU(s) list: 0-1023 Thread(s) per core: 8 Core(s) per socket: 32 Socket(s): 4 NUMA node(s): 4 NUMA node0 CPU(s): 0-255 NUMA node1 CPU(s): 256-511 NUMA node2 CPU(s): 512-767 NUMA node3 CPU(s): 768-1023 Most of this patch was done by Chris with updates by David. Signed-off-by: Chris Hyser <chris.hyser@oracle.com> Signed-off-by: David Ahern <david.ahern@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: fatal trap should stop all cpusDave Kleikamp2015-03-011-3/+24
| | | | | | | | | | "echo c > /proc/sysrq-trigger" does not result in a system crash. There are two problems. One is that the trap handler ignores the global variable, panic_on_oops. The other is that smp_send_stop() is a no-op which leaves the other cpus running normally when one cpu panics. Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Do irq_{enter,exit}() around generic_smp_call_function*().David S. Miller2014-11-071-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Otherwise rcu_irq_{enter,exit}() do not happen and we get dumps like: ==================== [ 188.275021] =============================== [ 188.309351] [ INFO: suspicious RCU usage. ] [ 188.343737] 3.18.0-rc3-00068-g20f3963-dirty #54 Not tainted [ 188.394786] ------------------------------- [ 188.429170] include/linux/rcupdate.h:883 rcu_read_lock() used illegally while idle! [ 188.505235] other info that might help us debug this: [ 188.554230] RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 [ 188.637587] RCU used illegally from extended quiescent state! [ 188.690684] 3 locks held by swapper/7/0: [ 188.721932] #0: (&x->wait#11){......}, at: [<0000000000495de8>] complete+0x8/0x60 [ 188.797994] #1: (&p->pi_lock){-.-.-.}, at: [<000000000048510c>] try_to_wake_up+0xc/0x400 [ 188.881343] #2: (rcu_read_lock){......}, at: [<000000000048a910>] select_task_rq_fair+0x90/0xb40 [ 188.973043]stack backtrace: [ 188.993879] CPU: 7 PID: 0 Comm: swapper/7 Not tainted 3.18.0-rc3-00068-g20f3963-dirty #54 [ 189.076187] Call Trace: [ 189.089719] [0000000000499360] lockdep_rcu_suspicious+0xe0/0x100 [ 189.147035] [000000000048a99c] select_task_rq_fair+0x11c/0xb40 [ 189.202253] [00000000004852d8] try_to_wake_up+0x1d8/0x400 [ 189.252258] [000000000048554c] default_wake_function+0xc/0x20 [ 189.306435] [0000000000495554] __wake_up_common+0x34/0x80 [ 189.356448] [00000000004955b4] __wake_up_locked+0x14/0x40 [ 189.406456] [0000000000495e08] complete+0x28/0x60 [ 189.448142] [0000000000636e28] blk_end_sync_rq+0x8/0x20 [ 189.496057] [0000000000639898] __blk_mq_end_request+0x18/0x60 [ 189.550249] [00000000006ee014] scsi_end_request+0x94/0x180 [ 189.601286] [00000000006ee334] scsi_io_completion+0x1d4/0x600 [ 189.655463] [00000000006e51c4] scsi_finish_command+0xc4/0xe0 [ 189.708598] [00000000006ed958] scsi_softirq_done+0x118/0x140 [ 189.761735] [00000000006398ec] __blk_mq_complete_request_remote+0xc/0x20 [ 189.827383] [00000000004c75d0] generic_smp_call_function_single_interrupt+0x150/0x1c0 [ 189.906581] [000000000043e514] smp_call_function_single_client+0x14/0x40 ==================== Based almost entirely upon a patch by Paul E. McKenney. Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'locking-arch-for-linus' of ↵Linus Torvalds2014-10-131-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull arch atomic cleanups from Ingo Molnar: "This is a series kept separate from the main locking tree, which cleans up and improves various details in the atomics type handling: - Remove the unused atomic_or_long() method - Consolidate and compress atomic ops implementations between architectures, to reduce linecount and to make it easier to add new ops. - Rewrite generic atomic support to only require cmpxchg() from an architecture - generate all other methods from that" * 'locking-arch-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read() locking, mips: Fix atomics locking, sparc64: Fix atomics locking,arch: Rewrite generic atomic support locking,arch,xtensa: Fold atomic_ops locking,arch,sparc: Fold atomic_ops locking,arch,sh: Fold atomic_ops locking,arch,powerpc: Fold atomic_ops locking,arch,parisc: Fold atomic_ops locking,arch,mn10300: Fold atomic_ops locking,arch,mips: Fold atomic_ops locking,arch,metag: Fold atomic_ops locking,arch,m68k: Fold atomic_ops locking,arch,m32r: Fold atomic_ops locking,arch,ia64: Fold atomic_ops locking,arch,hexagon: Fold atomic_ops locking,arch,cris: Fold atomic_ops locking,arch,avr32: Fold atomic_ops locking,arch,arm64: Fold atomic_ops locking,arch,arm: Fold atomic_ops ...
| * locking,arch,sparc: Fold atomic_opsPeter Zijlstra2014-08-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many of the atomic op implementations are the same except for one instruction; fold the lot into a few CPP macros and reduce LoC. This also prepares for easy addition of new ops. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Kirill Tkhai <tkhai@yandex.ru> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/20140508135852.825281379@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sparc64: Switch to 4-level page tables.David S. Miller2014-10-051-0/+7
| | | | | | | | | | | | | | | | | | | | This has become necessary with chips that support more than 43-bits of physical addressing. Based almost entirely upon a patch by Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
* | sparc64: Fix pcr_ops initialization and usage bugs.David S. Miller2014-08-111-1/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | Christopher reports that perf_event_print_debug() can crash in uniprocessor builds. The crash is due to pcr_ops being NULL. This happens because pcr_arch_init() is only invoked by smp_cpus_done() which only executes in SMP builds. init_hw_perf_events() is closely intertwined with pcr_ops being setup properly, therefore: 1) Call pcr_arch_init() early on from init_hw_perf_events(), instead of from smp_cpus_done(). 2) Do not hook up a PMU type if pcr_ops is NULL after pcr_arch_init(). 3) Move init_hw_perf_events to a later initcall so that it we will be sure to invoke pcr_arch_init() after all cpus are brought up. Finally, guard the one naked sequence of pcr_ops dereferences in __global_pmu_self() with an appropriate NULL check. Reported-by: Christopher Alexander Tobias Schulze <cat.schulze@alice-dsl.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-nextLinus Torvalds2014-06-191-13/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull sparc fixes from David Miller: "Sparc sparse fixes from Sam Ravnborg" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next: (67 commits) sparc64: fix sparse warnings in int_64.c sparc64: fix sparse warning in ftrace.c sparc64: fix sparse warning in kprobes.c sparc64: fix sparse warning in kgdb_64.c sparc64: fix sparse warnings in compat_audit.c sparc64: fix sparse warnings in init_64.c sparc64: fix sparse warnings in aes_glue.c sparc: fix sparse warnings in smp_32.c + smp_64.c sparc64: fix sparse warnings in perf_event.c sparc64: fix sparse warnings in kprobes.c sparc64: fix sparse warning in tsb.c sparc64: clean up compat_sigset_t.seta handling sparc64: fix sparse "Should it be static?" warnings in signal32.c sparc64: fix sparse warnings in sys_sparc32.c sparc64: fix sparse warning in pci.c sparc64: fix sparse warnings in smp_64.c sparc64: fix sparse warning in prom_64.c sparc64: fix sparse warning in btext.c sparc64: fix sparse warnings in sys_sparc_64.c + unaligned_64.c sparc64: fix sparse warning in process_64.c ... Conflicts: arch/sparc/include/asm/pgtable_64.h
| * sparc64: fix sparse warnings in init_64.cSam Ravnborg2014-05-181-5/+1
| | | | | | | | | | | | | | | | | | | | | | Fix following warnings: init_64.c:191:10: warning: symbol 'dcpage_flushes' was not declared. Should it be static? init_64.c:193:10: warning: symbol 'dcpage_flushes_xcall' was not declared. Should it be static? Add extern declaration to asm/setup.h and drop local declaration in smp_64.h Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * sparc: fix sparse warnings in smp_32.c + smp_64.cSam Ravnborg2014-05-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Fix following warnings: smp_32.c:177:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static? smp_64.c:1202:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static? smp_64.c:989:6: warning: symbol 'kgdb_roundup_cpus' was not declared. Should it be static? Add prototype to include/linux/profile.h of setup_profiling_timer Add missing include to smp_64.c Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * sparc64: fix sparse warnings in smp_64.cSam Ravnborg2014-05-181-8/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix following warnings: smp_64.c:88:6: warning: symbol 'smp_callin' was not declared. Should it be static? smp_64.c:133:6: warning: symbol 'cpu_panic' was not declared. Should it be static? smp_64.c:187:6: warning: symbol 'smp_synchronize_tick_client' was not declared. Should it be static? smp_64.c:821:18: warning: symbol 'smp_call_function_client' was not declared. Should it be static? smp_64.c:827:18: warning: symbol 'smp_call_function_single_client' was not declared. Should it be static? smp_64.c:964:18: warning: symbol 'smp_new_mmu_context_version_client' was not declared. Should it be static? smp_64.c:1149:6: warning: symbol 'smp_capture' was not declared. Should it be static? smp_64.c:1171:6: warning: symbol 'smp_release' was not declared. Should it be static? smp_64.c:1190:18: warning: symbol 'smp_penguin_jailcell' was not declared. Should it be static? smp_64.c:1410:18: warning: symbol 'smp_receive_signal_client' was not declared. Should it be static? Add prototypes in kernel.h or asm/smp_64.h as appropriate. Delete duplicate function kimage_addr_to_ra(), and adapt parameter to const void * to match the broader use. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | sparc64: Make itc_sync_lock rawKirill Tkhai2014-05-021-3/+3
|/ | | | | | | | | | | One more place where we must not be able to be preempted or to be interrupted in RT. Always actually disable interrupts during synchronization cycle. Signed-off-by: Kirill Tkhai <tkhai@yandex.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64, sched: Remove unused sparc64_multi_coreBjorn Helgaas2014-03-111-2/+0
| | | | | | | | | | | | | | Remove sparc64_multi_core because it's not used any more. It was added by a2f9f6bbb30e ("Fix {mc,smt}_capable()"), and the last uses were removed by e637d96bf462 ("sched: Remove unused mc_capable() and smt_capable()"). Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/20140304210744.16893.75929.stgit@bhelgaas-glaptop.roam.corp.google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sparc64: smp_callin: Enable irqs after preemption is disabledKirill Tkhai2014-01-041-1/+2
| | | | | | | | Most of other architectures have below suggested order. So lets do the same to fit generic idle loop scheme better. Signed-off-by: Kirill Tkhai <tkhai@yandex.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Add self-IPI support for smp_send_reschedule()Kirill Tkhai2013-11-141-2/+7
| | | | | | | | | | | | | | | CONFIG_NO_HZ_FULL requires possibility of smp_send_reschedule() for the calling CPU. Currently, it is used in inc_nr_running() scheduler primitive only. Nobody calls smp_send_reschedule() from preemptible context (furthermore, it looks like it will be save if anybody use it another way in the future). But anyway I add WARN_ON() here just to return here if anything changes. Signed-off-by: Kirill Tkhai <tkhai@yandex.ru> CC: David Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc: delete __cpuinit/__CPUINIT usage from all usersPaul Gortmaker2013-07-141-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) are flagged as __cpuinit -- so if we remove the __cpuinit from arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the arch/sparc uses of the __cpuinit macros from C files and removes __CPUINIT from assembly files. Note that even though arch/sparc/kernel/trampoline_64.S has instances of ".previous" in it, they are all paired off against explicit ".section" directives, and not implicitly paired with __CPUINIT (unlike mips and arm were). [1] https://lkml.org/lkml/2013/5/20/589 Cc: "David S. Miller" <davem@davemloft.net> Cc: sparclinux@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds2013-04-301-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull SMP/hotplug changes from Ingo Molnar: "This is a pretty large, multi-arch series unifying and generalizing the various disjunct pieces of idle routines that architectures have historically copied from each other and have grown in random, wildly inconsistent and sometimes buggy directions: 101 files changed, 455 insertions(+), 1328 deletions(-) this went through a number of review and test iterations before it was committed, it was tested on various architectures, was exposed to linux-next for quite some time - nevertheless it might cause problems on architectures that don't read the mailing lists and don't regularly test linux-next. This cat herding excercise was motivated by the -rt kernel, and was brought to you by Thomas "the Whip" Gleixner." * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) idle: Remove GENERIC_IDLE_LOOP config switch um: Use generic idle loop ia64: Make sure interrupts enabled when we "safe_halt()" sparc: Use generic idle loop idle: Remove unused ARCH_HAS_DEFAULT_IDLE bfin: Fix typo in arch_cpu_idle() xtensa: Use generic idle loop x86: Use generic idle loop unicore: Use generic idle loop tile: Use generic idle loop tile: Enter idle with preemption disabled sh: Use generic idle loop score: Use generic idle loop s390: Use generic idle loop powerpc: Use generic idle loop parisc: Use generic idle loop openrisc: Use generic idle loop mn10300: Use generic idle loop mips: Use generic idle loop microblaze: Use generic idle loop ...
| * sparc: Use generic idle loopSam Ravnborg2013-04-131-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add generic cpu_idle support sparc32: - replace call to cpu_idle() with cpu_startup_entry() - add arch_cpu_idle() sparc64: - smp_callin() now include cpu_startup_entry() call so we can skip calling cpu_idle from assembler - add arch_cpu_idle() and arch_cpu_idle_dead() Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Reviewed-by: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Cc: torvalds@linux-foundation.org Cc: rusty@rustcorp.com.au Cc: paulmck@linux.vnet.ibm.com Cc: peterz@infradead.org Cc: magnus.damm@gmail.com Acked-by: David Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/20130411193850.GA2330@merkur.ravnborg.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | sparc64: Fix race in TLB batch processing.David S. Miller2013-04-191-4/+37
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As reported by Dave Kleikamp, when we emit cross calls to do batched TLB flush processing we have a race because we do not synchronize on the sibling cpus completing the cross call. So meanwhile the TLB batch can be reset (tb->tlb_nr set to zero, etc.) and either flushes are missed or flushes will flush the wrong addresses. Fix this by using generic infrastructure to synchonize on the completion of the cross call. This first required getting the flush_tlb_pending() call out from switch_to() which operates with locks held and interrupts disabled. The problem is that smp_call_function_many() cannot be invoked with IRQs disabled and this is explicitly checked for with WARN_ON_ONCE(). We get the batch processing outside of locked IRQ disabled sections by using some ideas from the powerpc port. Namely, we only batch inside of arch_{enter,leave}_lazy_mmu_mode() calls. If we're not in such a region, we flush TLBs synchronously. 1) Get rid of xcall_flush_tlb_pending and per-cpu type implementations. 2) Do TLB batch cross calls instead via: smp_call_function_many() tlb_pending_func() __flush_tlb_pending() 3) Batch only in lazy mmu sequences: a) Add 'active' member to struct tlb_batch b) Define __HAVE_ARCH_ENTER_LAZY_MMU_MODE c) Set 'active' in arch_enter_lazy_mmu_mode() d) Run batch and clear 'active' in arch_leave_lazy_mmu_mode() e) Check 'active' in tlb_batch_add_one() and do a synchronous flush if it's clear. 4) Add infrastructure for synchronous TLB page flushes. a) Implement __flush_tlb_page and per-cpu variants, patch as needed. b) Likewise for xcall_flush_tlb_page. c) Implement smp_flush_tlb_page() to invoke the cross-call. d) Wire up global_flush_tlb_page() to the right routine based upon CONFIG_SMP 5) It turns out that singleton batches are very common, 2 out of every 3 batch flushes have only a single entry in them. The batch flush waiting is very expensive, both because of the poll on sibling cpu completeion, as well as because passing the tlb batch pointer to the sibling cpus invokes a shared memory dereference. Therefore, in flush_tlb_pending(), if there is only one entry in the batch perform a completely asynchronous global_flush_tlb_page() instead. Reported-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
* SPARC: drivers: remove __dev* attributes.Greg Kroah-Hartman2013-01-031-2/+2
| | | | | | | | | | | | | | | CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitdata, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sparc64: Add global PMU register dumping via sysrq.David S. Miller2012-10-161-0/+11
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* SPARC: SMP: Remove call to ipi_call_lock_irq()/ipi_call_unlock_irq()Yong Zhang2012-06-051-6/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | ipi_call_lock/unlock() lock resp. unlock call_function.lock. This lock protects only the call_function data structure itself, but it's completely unrelated to cpu_online_mask. The mask to which the IPIs are sent is calculated before call_function.lock is taken in smp_call_function_many(), so the locking around set_cpu_online() is pointless and can be removed. Delay irq enable to after set_cpu_online(). [ tglx: Massaged changelog ] Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> Cc: ralf@linux-mips.org Cc: sshtylyov@mvista.com Cc: david.daney@cavium.com Cc: nikunj@linux.vnet.ibm.com Cc: paulmck@linux.vnet.ibm.com Cc: axboe@kernel.dk Cc: peterz@infradead.org Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/20120529082732.GA4250@zhy Acked-by: "David S. Miller" <davem@davemloft.net> Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* sparc: Use generic idle thread allocationThomas Gleixner2012-04-261-7/+3
| | | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Tested-by: David S. Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/20120420124558.055198736@linutronix.de
* smp: Add task_struct argument to __cpu_up()Thomas Gleixner2012-04-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Preparatory patch to make the idle thread allocation for secondary cpus generic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Howells <dhowells@redhat.com> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: David S. Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Richard Weinberger <richard@nod.at> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
* treewide: Fix typos in various parts of the kernel, and fix some comments.Justin P. Mattock2011-12-021-1/+1
| | | | | | | | | The below patch fixes some typos in various parts of the kernel, as well as fixes some comments. Please let me know if I missed anything, and I will try to get it changed and resent. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* sparc: move symbol exporters to use export.h not module.hPaul Gortmaker2011-10-311-1/+1
| | | | | | | | Many of the core sparc kernel files are not modules, but just including module.h for exporting symbols. Now these files can use the lighter footprint export.h for this role. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* atomic: use <linux/atomic.h>Arun Sharma2011-07-261-1/+1
| | | | | | | | | | | | | | This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge commit '317f394160e9beb97d19a84c39b7e5eb3d7815a8'David S. Miller2011-05-201-0/+1
|\ | | | | | | | | | | | | | | | | Conflicts: arch/sparc/kernel/smp_32.c With merge conflict help from Daniel Hellstrom. Signed-off-by: David S. Miller <davem@davemloft.net>
| * sched: Provide scheduler_ipi() callback in response to smp_send_reschedule()Peter Zijlstra2011-04-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For future rework of try_to_wake_up() we'd like to push part of that function onto the CPU the task is actually going to run on. In order to do so we need a generic callback from the existing scheduler IPI. This patch introduces such a generic callback: scheduler_ipi() and implements it as a NOP. BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions! Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Reviewed-by: Frank Rowand <frank.rowand@am.sony.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
* | sparc: convert old cpumask API into new oneKOSAKI Motohiro2011-05-161-29/+29
|/ | | | | | | | | | | | | | | | Adapt new API. Almost change is trivial, most important change are to remove following like =operator. cpumask_t cpu_mask = *mm_cpumask(mm); cpus_allowed = current->cpus_allowed; Because cpumask_var_t is =operator unsafe. These usage might prevent kernel core improvement. No functional change. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Fix build errors with gcc-4.6.0David S. Miller2011-03-161-7/+4
| | | | | | | | | | | Most of the warnings emitted (we fail arch/sparc file builds with -Werror) were legitimate but harmless, however one case (n2_pcr_write) was a genuine bug. Based almost entirely upon a patch by Sam Ravnborg. Reported-by: Dennis Gilmore <dennis@ausil.us> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Fix NMI startup bug which also breaks perf.David S. Miller2011-02-151-0/+2
| | | | | | | | | | | | | Doing NMI startup as an early initcall doesn't work because we need to have SMP started up by then. So we'd only NMI startup one cpu, which causes perf PMU grab to BUG because the nmi_active count isn't what it's supposed to be. This also points out that we don't have proper CPU up/down notifiers for the NMI code which will need to be fixed at some point. Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller2010-04-131-0/+1
|\ | | | | | | | | Conflicts: lib/Kconfig.debug
| * include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* | sparc64: Add function graph tracer support.David S. Miller2010-04-121-5/+6
|/ | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* of: unify phandle name in struct device_nodeGrant Likely2010-01-281-1/+1
| | | | | | | | | | | | | | | | | | | | | In struct device_node, the phandle is named 'linux_phandle' for PowerPC and MicroBlaze, and 'node' for SPARC. There is no good reason for the difference, it is just an artifact of the code diverging over a couple of years. This patch renames both to simply .phandle. Note: the .node also existed in PowerPC/MicroBlaze, but the only user seems to be arch/powerpc/platforms/powermac/pfunc_core.c. It doesn't look like the assignment between .linux_phandle and .node is significantly different enough to warrant the separate code paths unless ibm,phandle properties actually appear in Apple device trees. I think it is safe to eliminate the old .node property and use phandle everywhere. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* sparc64: implement page mapping percpu first chunk allocatorTejun Heo2009-09-291-9/+44
| | | | | | | | | | | | | | | | | | | Implement page mapping percpu first chunk allocator as a fallback to the embedding allocator. The next patch will make the embedding allocator check distances between units to determine whether it fits within the vmalloc area so that this fallback can be used on such cases. sparc64 currently has relatively small vmalloc area which makes it impossible to create any dynamic chunks on certain configurations leading to percpu allocation failures. This and the next patch should allow those configurations to keep working until proper solution is found. While at it, mark pcpu_cpu_distance() with __init. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net>
* sparc64: use embedding percpu first chunk allocatorTejun Heo2009-08-141-110/+18
| | | | | | | | | | | | | | | | sparc64 currently allocates a large page for each cpu and partially remap them into vmalloc area much like what lpage first chunk allocator did. As a 4M page is used for each cpu, this results in very large unit size and also adds TLB pressure due to the double mapping of pages in the first chunk. This patch converts sparc64 to use the embedding percpu first chunk allocator which now knows how to handle NUMA configurations. This simplifies the code a lot, doesn't incur any extra TLB pressure and results in better utilization of address space. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net>
* percpu: add pcpu_unit_offsets[]Tejun Heo2009-08-141-5/+7
| | | | | | | | | | | | | | | | | | | Currently units are mapped sequentially into address space. This patch adds pcpu_unit_offsets[] which allows units to be mapped to arbitrary offsets from the chunk base address. This is necessary to allow sparse embedding which might would need to allocate address ranges and memory areas which aren't aligned to unit size but allocation atom size (page or large page size). This also simplifies things a bit by removing the need to calculate offset from unit number. With this change, there's no need for the arch code to know pcpu_unit_size. Update pcpu_setup_first_chunk() and first chunk allocators to return regular 0 or -errno return code instead of unit size or -errno. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: David S. Miller <davem@davemloft.net>
* percpu: introduce pcpu_alloc_info and pcpu_group_infoTejun Heo2009-08-141-7/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Till now, non-linear cpu->unit map was expressed using an integer array which maps each cpu to a unit and used only by lpage allocator. Although how many units have been placed in a single contiguos area (group) is known while building unit_map, the information is lost when the result is recorded into the unit_map array. For lpage allocator, as all allocations are done by lpages and whether two adjacent lpages are in the same group or not is irrelevant, this didn't cause any problem. Non-linear cpu->unit mapping will be used for sparse embedding and this grouping information is necessary for that. This patch introduces pcpu_alloc_info which contains all the information necessary for initializing percpu allocator. pcpu_alloc_info contains array of pcpu_group_info which describes how units are grouped and mapped to cpus. pcpu_group_info also has base_offset field to specify its offset from the chunk's base address. pcpu_build_alloc_info() initializes this field as if all groups are allocated back-to-back as is currently done but this will be used to sparsely place groups. pcpu_alloc_info is a rather complex data structure which contains a flexible array which in turn points to nested cpu_map arrays. * pcpu_alloc_alloc_info() and pcpu_free_alloc_info() are provided to help dealing with pcpu_alloc_info. * pcpu_lpage_build_unit_map() is updated to build pcpu_alloc_info, generalized and renamed to pcpu_build_alloc_info(). @cpu_distance_fn may be NULL indicating that all cpus are of LOCAL_DISTANCE. * pcpul_lpage_dump_cfg() is updated to process pcpu_alloc_info, generalized and renamed to pcpu_dump_alloc_info(). It now also prints which group each alloc unit belongs to. * pcpu_setup_first_chunk() now takes pcpu_alloc_info instead of the separate parameters. All first chunk allocators are updated to use pcpu_build_alloc_info() to build alloc_info and call pcpu_setup_first_chunk() with it. This has the side effect of packing units for sparse possible cpus. ie. if cpus 0, 2 and 4 are possible, they'll be assigned unit 0, 1 and 2 instead of 0, 2 and 4. * x86 setup_pcpu_lpage() is updated to deal with alloc_info. * sparc64 setup_per_cpu_areas() is updated to build alloc_info. Although the changes made by this patch are pretty pervasive, it doesn't cause any behavior difference other than packing of sparse cpus. It mostly changes how information is passed among initialization functions and makes room for more flexibility. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net>
* Merge branch 'percpu-for-linus' into percpu-for-nextTejun Heo2009-08-141-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/sparc/kernel/smp_64.c arch/x86/kernel/cpu/perf_counter.c arch/x86/kernel/setup_percpu.c drivers/cpufreq/cpufreq_ondemand.c mm/percpu.c Conflicts in core and arch percpu codes are mostly from commit ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all the first chunk allocators into mm/percpu.c, the changes are moved from arch code to mm/percpu.c. Signed-off-by: Tejun Heo <tj@kernel.org>
| * percpu, sparc64: fix sparse possible cpu map handlingTejun Heo2009-08-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | percpu code has been assuming num_possible_cpus() == nr_cpu_ids which is incorrect if cpu_possible_map contains holes. This causes percpu code to access beyond allocated memories and vmalloc areas. On a sparc64 machine with cpus 0 and 2 (u60), this triggers the following warning or fails boot. WARNING: at /devel/tj/os/work/mm/vmalloc.c:106 vmap_page_range_noflush+0x1f0/0x240() Modules linked in: Call Trace: [00000000004b17d0] vmap_page_range_noflush+0x1f0/0x240 [00000000004b1840] map_vm_area+0x20/0x60 [00000000004b1950] __vmalloc_area_node+0xd0/0x160 [0000000000593434] deflate_init+0x14/0xe0 [0000000000583b94] __crypto_alloc_tfm+0xd4/0x1e0 [00000000005844f0] crypto_alloc_base+0x50/0xa0 [000000000058b898] alg_test_comp+0x18/0x80 [000000000058dad4] alg_test+0x54/0x180 [000000000058af00] cryptomgr_test+0x40/0x60 [0000000000473098] kthread+0x58/0x80 [000000000042b590] kernel_thread+0x30/0x60 [0000000000472fd0] kthreadd+0xf0/0x160 ---[ end trace 429b268a213317ba ]--- This patch fixes generic percpu functions and sparc64 setup_per_cpu_areas() so that they handle sparse cpu_possible_map properly. Please note that on x86, cpu_possible_map() doesn't contain holes and thus num_possible_cpus() == nr_cpu_ids and this patch doesn't cause any behavior difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@elte.hu>
* | percpu: allow non-linear / sparse cpu -> unit mappingTejun Heo2009-07-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently cpu and unit are always identity mapped. To allow more efficient large page support on NUMA and lazy allocation for possible but offline cpus, cpu -> unit mapping needs to be non-linear and/or sparse. This can be easily implemented by adding a cpu -> unit mapping array and using it whenever looking up the matching unit for a cpu. The only unusal conversion is in pcpu_chunk_addr_search(). The passed in address is unit0 based and unit0 might not be in use so it needs to be converted to address of an in-use unit. This is easily done by adding the unit offset for the current processor. [ Impact: allows non-linear/sparse cpu -> unit mapping, no visible change yet ] Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net>