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2013-11-12Merge tag 'devicetree-for-3.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull devicetree updates from Rob Herring: "DeviceTree updates for 3.13. This is a bit larger pull request than usual for this cycle with lots of clean-up. - Cross arch clean-up and consolidation of early DT scanning code. - Clean-up and removal of arch prom.h headers. Makes arch specific prom.h optional on all but Sparc. - Addition of interrupts-extended property for devices connected to multiple interrupt controllers. - Refactoring of DT interrupt parsing code in preparation for deferred probe of interrupts. - ARM cpu and cpu topology bindings documentation. - Various DT vendor binding documentation updates" * tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (82 commits) powerpc: add missing explicit OF includes for ppc dt/irq: add empty of_irq_count for !OF_IRQ dt: disable self-tests for !OF_IRQ of: irq: Fix interrupt-map entry matching MIPS: Netlogic: replace early_init_devtree() call of: Add Panasonic Corporation vendor prefix of: Add Chunghwa Picture Tubes Ltd. vendor prefix of: Add AU Optronics Corporation vendor prefix of/irq: Fix potential buffer overflow of/irq: Fix bug in interrupt parsing refactor. of: set dma_mask to point to coherent_dma_mask of: add vendor prefix for PHYTEC Messtechnik GmbH DT: sort vendor-prefixes.txt of: Add vendor prefix for Cadence of: Add empty for_each_available_child_of_node() macro definition arm/versatile: Fix versatile irq specifications. of/irq: create interrupts-extended property microblaze/pci: Drop PowerPC-ism from irq parsing of/irq: Create of_irq_parse_and_map_pci() to consolidate arch code. of/irq: Use irq_of_parse_and_map() ...
2013-11-12Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "The main changes in this cycle are: - (much) improved CONFIG_NUMA_BALANCING support from Mel Gorman, Rik van Riel, Peter Zijlstra et al. Yay! - optimize preemption counter handling: merge the NEED_RESCHED flag into the preempt_count variable, by Peter Zijlstra. - wait.h fixes and code reorganization from Peter Zijlstra - cfs_bandwidth fixes from Ben Segall - SMP load-balancer cleanups from Peter Zijstra - idle balancer improvements from Jason Low - other fixes and cleanups" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits) ftrace, sched: Add TRACE_FLAG_PREEMPT_RESCHED stop_machine: Fix race between stop_two_cpus() and stop_cpus() sched: Remove unnecessary iteration over sched domains to update nr_busy_cpus sched: Fix asymmetric scheduling for POWER7 sched: Move completion code from core.c to completion.c sched: Move wait code from core.c to wait.c sched: Move wait.c into kernel/sched/ sched/wait: Fix __wait_event_interruptible_lock_irq_timeout() sched: Avoid throttle_cfs_rq() racing with period_timer stopping sched: Guarantee new group-entities always have weight sched: Fix hrtimer_cancel()/rq->lock deadlock sched: Fix cfs_bandwidth misuse of hrtimer_expires_remaining sched: Fix race on toggling cfs_bandwidth_used sched: Remove extra put_online_cpus() inside sched_setaffinity() sched/rt: Fix task_tick_rt() comment sched/wait: Fix build breakage sched/wait: Introduce prepare_to_wait_event() sched/wait: Add ___wait_cond_timeout() to wait_event*_timeout() too sched: Remove get_online_cpus() usage sched: Fix race in migrate_swap_stop() ...
2013-11-07Merge remote-tracking branch 'grant/devicetree/next' into for-nextRob Herring
2013-11-07ARC: [plat-arcfpga] defconfig updateVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-07smp, ARC: kill SMP single function call interruptJiang Liu
Commit 9a46ad6d6df3b54 "smp: make smp_call_function_many() use logic similar to smp_call_function_single()" has unified the way to handle single and multiple cross-CPU function calls. Now only one interrupt is needed for architecture specific code to support generic SMP function call interfaces, so kill the redundant single function call interrupt. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-07ARC: [SMP] Disallow RTSCVineet Gupta
RTSC is strictly incore and must not be allowed in SMP configs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: [SMP] Fix build failures for large NR_CPUSVineet Gupta
ST.as only takes S9 (255) for offset. This was going out of range when accessing a task_struct field with 4k NR_CPUS (due to 128b of coumaks itself in there). Workaround by using an intermediate register to do the address scaling. There is some duplication of fix for ctx_sw.c and ctx_sw_asm.S however given that C version will go away soon I'm not bothering to factor out the common code. Reported-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: [SMP] enlarge possible NR_CPUSNoam Camus
Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: [SMP] TLB flushVineet Gupta
- Add mm_cpumask setting (aggregating only, unlike some other arches) used to restrict the TLB flush cross-calling - cross-calling versions of TLB flush routines (thanks to Noam) Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: [SMP] ASID allocationVineet Gupta
-Track a Per CPU ASID counter -mm-per-cpu ASID (multiple threads, or mm migrated around) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06arc: export symbol for pm_power_off in reset.cChen Gang
Need export symbol for it, or can not pass compiling, the related error with allmodconfig: MODPOST 2994 modules ERROR: "pm_power_off" [drivers/mfd/retu-mfd.ko] undefined! ERROR: "pm_power_off" [drivers/char/ipmi/ipmi_poweroff.ko] undefined! Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06arc: export symbol for save_stack_trace() in stacktrace.cChen Gang
Need export its symbol just like other architectures done, or can not pass compiling with allmodconfig, the related error: MODPOST 2994 modules ERROR: "save_stack_trace" [kernel/backtracetest.ko] undefined! ERROR: "save_stack_trace" [drivers/md/persistent-data/dm-persistent-data.ko] undefined! Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06arc: remove '__init' for get_hw_config_num_irq()Chen Gang
get_hw_config_num_irq() may be called by normal iss_model_init_smp() which is a function pointer for 'init_smp' which may be called by first_lines_of_secondary() which also need be normal too. The related warning (with allmodconfig): MODPOST vmlinux.o WARNING: vmlinux.o(.text+0x5814): Section mismatch in reference from the function iss_model_init_smp() to the function .init.text:get_hw_config_num_irq() The function iss_model_init_smp() references the function __init get_hw_config_num_irq(). This is often because iss_model_init_smp lacks a __init annotation or the annotation of get_hw_config_num_irq is wrong. Signed-off-by: Chen Gang <gang.chen@asianux.com>
2013-11-06arc: remove '__init' for first_lines_of_secondary()Chen Gang
first_lines_of_secondary() is a '__init' function, but it may be called by __cpu_up() by _cpu_up() by cpu_up() which is a normal export symbol function. So recommend to remove '__init'. The related warning (with allmodconfig): MODPOST vmlinux.o WARNING: vmlinux.o(.text+0x315c): Section mismatch in reference from the function __cpu_up() to the function .init.text:first_lines_of_secondary() The function __cpu_up() references the function __init first_lines_of_secondary(). This is often because __cpu_up lacks a __init annotation or the annotation of first_lines_of_secondary is wrong. Signed-off-by: Chen Gang <gang.chen@asianux.com>
2013-11-06arc: remove '__init' for setup_processor() and arc_init_IRQ()Chen Gang
They haven't '__init' in definition, but has '__init' in declaration. And normal function start_kernel_secondary() may call setup_processor() which will call arc_init_IRQ(). So need remove '__init' for both of them. The related warning (with allmodconfig): MODPOST vmlinux.o WARNING: vmlinux.o(.text+0x3084): Section mismatch in reference from the function start_kernel_secondary() to the function .init.text:setup_processor() The function start_kernel_secondary() references the function __init setup_processor(). This is often because start_kernel_secondary lacks a __init annotation or the annotation of setup_processor is wrong. Signed-off-by: Chen Gang <gang.chen@asianux.com>
2013-11-06arc: kgdb: add default implementation for kgdb_roundup_cpus()Chen Gang
arc supports kgdb, but need update -- add function kgdb_roundup_cpus(), or can not pass compiling. At present, add the simple generic one just like other architectures(e.g. tile, mips ...). The related error (with allmodconfig): kernel/built-in.o: In function `kgdb_cpu_enter': kernel/debug/debug_core.c:580: undefined reference to `kgdb_roundup_cpus' Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: Fix bogus gcc warning and micro-optimise TLB iteration loopVineet Gupta
------------------>8---------------------- arch/arc/mm/tlb.c: In function ‘do_tlb_overlap_fault’: arch/arc/mm/tlb.c:688:13: warning: array subscript is above array bounds [-Warray-bounds] (pd0[n] & PAGE_MASK)) { ^ ------------------>8---------------------- While at it, remove the usless last iteration of outer loop when reading a TLB SET for duplicate entries. Suggested-by: Mischa Jonker <mjonker@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: Add support for irqflags tracing and lockdepVineet Gupta
Lockdep required a small fix to stacktrace API which was incorrectly unwindign out of __switch_to for the current call frame. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: Reset the value of Interrupt Priority RegisterVineet Gupta
In case bootloader has changed the priority of one/more IRQ lines Reported-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: Reduce #ifdef'ery for unaligned access emulationVineet Gupta
Emulation not enabled is treated as if the fixup failed, so no need for special #ifdef checks. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: Change calling convention of do_page_fault()Vineet Gupta
switch the args (address, pt_regs) to match with all the other "C" exception handlers. This removes the awkwardness in EV_ProtV for page fault vs. unaligned access. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: cacheflush optim - PTAG can be loop invariant if V-P is constVineet Gupta
Line op needs vaddr (indexing) and paddr (tag match). For page sized flushes (V-P const), each line op will need a different index, but the tag bits wil remain constant, hence paddr can be setup once outside the loop. This improves select LMBench numbers for Aliasing dcache where we have more "preventive" cache flushing. Processor, Processes - times in microseconds - smaller is better ------------------------------------------------------------------------------ Host OS Mhz null null open slct sig sig fork exec sh call I/O stat clos TCP inst hndl proc proc proc --------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- 3.11-rc7- Linux 3.11.0- 80 4.66 8.88 69.7 112. 268. 8.60 28.0 3489 13.K 27.K # Non alias ARC700 3.11-rc7- Linux 3.11.0- 80 4.64 8.51 68.6 98.5 271. 8.58 28.1 4160 15.K 32.K # Aliasing 3.11-rc7- Linux 3.11.0- 80 4.64 8.51 69.8 99.4 270. 8.73 27.5 3880 15.K 31.K # PTAG loop Inv Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: cacheflush refactor #3: Unify the {d,i}cache flush leaf helpersVineet Gupta
With Line length being constant now, we can fold the 2 helpers into 1. This allows applying any optimizations (forthcoming) to single place. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: cacheflush refactor #2: I and D caches lines to have same sizeVineet Gupta
Having them be different seems an obscure configuration. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: cacheflush refactor #1: push aux reg ascertaining into leaf routineVineet Gupta
ARC dcache supports 3 ops - Inv, Flush, Flush-n-Inv. The programming model however provides 2 commands FLUSH, INV. INV will either discard or flush-n-discard (based on DT_CTRL bit) The leaf helper __dc_line_loop() used to take the AUX register (corresponding to the 2 commands). Now we push that to within the helper, paving way for code consolidations to follow. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: use __weak instead of __attribute__((weak))Vineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06ARC: Annotate some functions as staticVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06arc: Replace __get_cpu_var usesChristoph Lameter
__get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : #define __get_cpu_var(var) (*this_cpu_ptr(&(var))) __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calcualtions are avoided and less registers are used when code is generated. At the end of the patchset all uses of __get_cpu_var have been removed so the macro is removed too. The patchset includes passes over all arches as well. Once these operations are used throughout then specialized macros can be defined in non -x86 arches as well in order to optimize per cpu access by f.e. using a global register that may be set to the per cpu base. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, u); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(this_cpu_ptr(&x), y, sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to this_cpu_inc(y) Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Christoph Lameter <cl@linux.com>
2013-11-02ARC: Incorrect mm reference used in vmalloc fault handlerVineet Gupta
A vmalloc fault needs to sync up PGD/PTE entry from init_mm to current task's "active_mm". ARC vmalloc fault handler however was using mm. A vmalloc fault for non user task context (actually pre-userland, from init thread's open for /dev/console) caused the handler to deref NULL mm (for mm->pgd) The reasons it worked so far is amazing: 1. By default (!SMP), vmalloc fault handler uses a cached value of PGD. In SMP that MMU register is repurposed hence need for mm pointer deref. 2. In pre-3.12 SMP kernel, the problem triggering vmalloc didn't exist in pre-userland code path - it was introduced with commit 20bafb3d23d108bc "n_tty: Move buffers into n_tty_data" Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com> Cc: Noam Camus <noamc@ezchip.com> Cc: stable@vger.kernel.org #3.10 and 3.11 Cc: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-01Merge branch 'linus' into sched/coreIngo Molnar
Resolve cherry-picking conflicts: Conflicts: mm/huge_memory.c mm/memory.c mm/mprotect.c See this upstream merge commit for more details: 52469b4fcd4f Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-12ARC: Ignore ptrace SETREGSET request for synthetic register "stop_pc"Vineet Gupta
ARCompact TRAP_S insn used for breakpoints, commits before exception is taken (updating architectural PC). So ptregs->ret contains next-PC and not the breakpoint PC itself. This is different from other restartable exceptions such as TLB Miss where ptregs->ret has exact faulting PC. gdb needs to know exact-PC hence ARC ptrace GETREGSET provides for @stop_pc which returns ptregs->ret vs. EFA depending on the situation. However, writing stop_pc (SETREGSET request), which updates ptregs->ret doesn't makes sense stop_pc doesn't always correspond to that reg as described above. This was not an issue so far since user_regs->ret / user_regs->stop_pc had same value and both writing to ptregs->ret was OK, needless, but NOT broken, hence not observed. With gdb "jump", they diverge, and user_regs->ret updating ptregs is overwritten immediately with stop_pc, which this patch fixes. Reported-by: Anton Kolesov <akolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-10-09of: remove empty arch prom.h headersRob Herring
Now that prom.h is optional, all the empty prom.h headers can be removed. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Grant Likely <grant.likely@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com>
2013-10-09of: remove HAVE_ARCH_DEVTREE_FIXUPSRob Herring
HAVE_ARCH_DEVTREE_FIXUPS appears to always be needed except for sparc, but it is only used for /proc/device-teee and sparc does not enable /proc/device-tree. So this option is redundant. Remove the option and always enable it. This has the side effect of fixing /proc/device-tree on arches such as arm64 which failed to define this option. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Grant Likely <grant.likely@linaro.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: James Hogan <james.hogan@imgtec.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com>
2013-10-09arc: remove unnecessary prom.h includesRob Herring
Remove unnecessary prom.h includes in preparation to remove prom.h. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Grant Likely <grant.likely@linaro.org>
2013-10-09arc: use common of_flat_dt_match_machineRob Herring
Convert arc to use the common of_flat_dt_match_machine function. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2013-10-09of: remove early_init_dt_setup_initrd_archRob Herring
All arches do essentially the same thing now for early_init_dt_setup_initrd_arch, so it can now be removed. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Acked-by: Grant Likely <grant.likely@linaro.org>
2013-10-09arc: use early_init_dt_scanRob Herring
Convert arc to use new early_init_dt_scan function. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2013-10-09arc: use unflatten_and_copy_device_treeRob Herring
Use the common unflatten_and_copy_device_tree to copy the built-in FDT out of init section. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Grant Likely <grant.likely@linaro.org>
2013-10-09Merge tag 'v3.12-rc4' into sched/coreIngo Molnar
Merge Linux v3.12-rc4 to fix a conflict and also to refresh the tree before applying more scheduler patches. Conflicts: arch/avr32/include/asm/Kbuild Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-03ARC: Fix signal frame management for SA_SIGINFOChristian Ruppert
Previously, when a signal was registered with SA_SIGINFO, parameters 2 and 3 of the signal handler were written to registers r1 and r2 before the register set was saved. This led to corruption of these two registers after returning from the signal handler (the wrong values were restored). With this patch, registers are now saved before any parameters are passed, thus maintaining the processor state from before signal entry. Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-09-27ARC: Use clockevents_config_and_register over clockevents_register_deviceUwe Kleine-König
clockevents_config_and_register is more clever and correct than doing it by hand; so use it. [vgupta: fixed build failure due to missing ; in patch] Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-09-27ARC: Workaround spinlock livelock in SMP SystemC simulationVineet Gupta
Some ARC SMP systems lack native atomic R-M-W (LLOCK/SCOND) insns and can only use atomic EX insn (reg with mem) to build higher level R-M-W primitives. This includes a SystemC based SMP simulation model. So rwlocks need to use a protecting spinlock for atomic cmp-n-exchange operation to update reader(s)/writer count. The spinlock operation itself looks as follows: mov reg, 1 ; 1=locked, 0=unlocked retry: EX reg, [lock] ; load existing, store 1, atomically BREQ reg, 1, rety ; if already locked, retry In single-threaded simulation, SystemC alternates between the 2 cores with "N" insn each based scheduling. Additionally for insn with global side effect, such as EX writing to shared mem, a core switch is enforced too. Given that, 2 cores doing a repeated EX on same location, Linux often got into a livelock e.g. when both cores were fiddling with tasklist lock (gdbserver / hackbench) for read/write respectively as the sequence diagram below shows: core1 core2 -------- -------- 1. spin lock [EX r=0, w=1] - LOCKED 2. rwlock(Read) - LOCKED 3. spin unlock [ST 0] - UNLOCKED spin lock [EX r=0,w=1] - LOCKED -- resched core 1---- 5. spin lock [EX r=1] - ALREADY-LOCKED -- resched core 2---- 6. rwlock(Write) - READER-LOCKED 7. spin unlock [ST 0] 8. rwlock failed, retry again 9. spin lock [EX r=0, w=1] -- resched core 1---- 10 spinlock locked in #9, retry #5 11. spin lock [EX gets 1] -- resched core 2---- ... ... The fix was to unlock using the EX insn too (step 7), to trigger another SystemC scheduling pass which would let core1 proceed, eliding the livelock. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-09-27ARC: Fix 32-bit wrap around in access_ok()Vineet Gupta
Anton reported | LTP tests syscalls/process_vm_readv01 and process_vm_writev01 fail | similarly in one testcase test_iov_invalid -> lvec->iov_base. | Testcase expects errno EFAULT and return code -1, | but it gets return code 1 and ERRNO is 0 what means success. Essentially test case was passing a pointer of -1 which access_ok() was not catching. It was doing [@addr + @sz <= TASK_SIZE] which would pass for @addr == -1 Fixed that by rewriting as [@addr <= TASK_SIZE - @sz] Reported-by: Anton Kolesov <Anton.Kolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-09-27ARC: Handle zero-overhead-loop in unaligned access handlerMischa Jonker
If a load or store is the last instruction in a zero-overhead-loop, and it's misaligned, the loop would execute only once. This fixes that problem. Signed-off-by: Mischa Jonker <mjonker@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-09-25sched, arch: Create asm/preempt.hPeter Zijlstra
In order to prepare to per-arch implementations of preempt_count move the required bits into an asm-generic header and use this for all archs. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-h5j0c1r3e3fk015m30h8f1zx@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-13Remove GENERIC_HARDIRQ config optionMartin Schwidefsky
After the last architecture switched to generic hard irqs the config options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code for !CONFIG_GENERIC_HARDIRQS can be removed. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-09-12Merge branch 'akpm' (patches from Andrew Morton)Linus Torvalds
Merge more patches from Andrew Morton: "The rest of MM. Plus one misc cleanup" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (35 commits) mm/Kconfig: add MMU dependency for MIGRATION. kernel: replace strict_strto*() with kstrto*() mm, thp: count thp_fault_fallback anytime thp fault fails thp: consolidate code between handle_mm_fault() and do_huge_pmd_anonymous_page() thp: do_huge_pmd_anonymous_page() cleanup thp: move maybe_pmd_mkwrite() out of mk_huge_pmd() mm: cleanup add_to_page_cache_locked() thp: account anon transparent huge pages into NR_ANON_PAGES truncate: drop 'oldsize' truncate_pagecache() parameter mm: make lru_add_drain_all() selective memcg: document cgroup dirty/writeback memory statistics memcg: add per cgroup writeback pages accounting memcg: check for proper lock held in mem_cgroup_update_page_stat memcg: remove MEMCG_NR_FILE_MAPPED memcg: reduce function dereference memcg: avoid overflow caused by PAGE_ALIGN memcg: rename RESOURCE_MAX to RES_COUNTER_MAX memcg: correct RESOURCE_MAX to ULLONG_MAX mm: memcg: do not trap chargers with full callstack on OOM mm: memcg: rework and document OOM waiting and wakeup ...
2013-09-12arch: mm: pass userspace fault flag to generic fault handlerJohannes Weiner
Unlike global OOM handling, memory cgroup code will invoke the OOM killer in any OOM situation because it has no way of telling faults occuring in kernel context - which could be handled more gracefully - from user-triggered faults. Pass a flag that identifies faults originating in user space from the architecture-specific fault handlers to generic code so that memcg OOM handling can be improved. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12arch: mm: remove obsolete init OOM protectionJohannes Weiner
The memcg code can trap tasks in the context of the failing allocation until an OOM situation is resolved. They can hold all kinds of locks (fs, mm) at this point, which makes it prone to deadlocking. This series converts memcg OOM handling into a two step process that is started in the charge context, but any waiting is done after the fault stack is fully unwound. Patches 1-4 prepare architecture handlers to support the new memcg requirements, but in doing so they also remove old cruft and unify out-of-memory behavior across architectures. Patch 5 disables the memcg OOM handling for syscalls, readahead, kernel faults, because they can gracefully unwind the stack with -ENOMEM. OOM handling is restricted to user triggered faults that have no other option. Patch 6 reworks memcg's hierarchical OOM locking to make it a little more obvious wth is going on in there: reduce locked regions, rename locking functions, reorder and document. Patch 7 implements the two-part OOM handling such that tasks are never trapped with the full charge stack in an OOM situation. This patch: Back before smart OOM killing, when faulting tasks were killed directly on allocation failures, the arch-specific fault handlers needed special protection for the init process. Now that all fault handlers call into the generic OOM killer (see commit 609838cfed97: "mm: invoke oom-killer from remaining unconverted page fault handlers"), which already provides init protection, the arch-specific leftovers can be removed. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12ARC: SMP failed to boot due to missing IVT setupNoam Camus
Commit 05b016ecf5e7a "ARC: Setup Vector Table Base in early boot" moved the Interrupt vector Table setup out of arc_init_IRQ() which is called for all CPUs, to entry point of boot cpu only, breaking booting of others. Fix by adding the same to entry point of non-boot CPUs too. read_arc_build_cfg_regs() printing IVT Base Register didn't help the casue since it prints a synthetic value if zero which is totally bogus, so fix that to print the exact Register. [vgupta: Remove the now stale comment from header of arc_init_IRQ and also added the commentary for halt-on-reset] Cc: Gilad Ben-Yossef <gilad@benyossef.com> Cc: Cc: <stable@vger.kernel.org> #3.11 Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>