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* Merge tag 'arc-v3.16-rc1' of ↵Linus Torvalds2014-06-09
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc Pull ARC updates from Vineet Gupta: "Nothing too exciting here, just minor fixes/cleanup. Only noteworthy ones are: - Moving cache disabling to early boot - ARC UART enabled only if earlyprintk setup in cmdline" * tag 'arc-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARC: Disable caches in early boot if so configured ARC: [arcfpga] Early ARC UART to be only activated by cmdline ARC: [arcfpga] Get rid of legacy BVCI latency unit support ARC: remove duplicate header exports ARC: arc_local_timer_setup() need not pass own cpu id ARC: Fixed spelling errors within comments ARC: make start_thread() out-of-line ARC: fix mmuv2 warning ARC: [SMP] ISS SMP extension bitrot
| * ARC: Disable caches in early boot if so configuredVineet Gupta2014-06-03
| | | | | | | | | | Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: arc_local_timer_setup() need not pass own cpu idVineet Gupta2014-06-03
| | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: Fixed spelling errors within commentsTerence Eden2014-05-05
| | | | | | | | | | | | | | | | [vgupta: fixed changelong + added Randy's suggestion] Signed-off-by: Terence Eden <github.com@shkspr.mobi> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: make start_thread() out-of-lineVineet Gupta2014-05-05
| | | | | | | | | | | | Helps move out ISA specific bits from a arch exported header Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: [SMP] ISS SMP extension bitrotVineet Gupta2014-05-05
| | | | | | | | | | | | | | * Move extension specific code out of common SMP code * Don't enable it by default for SMP Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | arc: call find_vma with the mmap_sem heldDavidlohr Bueso2014-06-04
| | | | | | | | | | | | | | | | | | | | | | | | | | Performing vma lookups without taking the mm->mmap_sem is asking for trouble. While doing the search, the vma in question can be modified or even removed before returning to the caller. Take the lock (shared) in order to avoid races while iterating through the vmacache and/or rbtree. [akpm@linux-foundation.org: CSE current->active_mm, per Vineet] Signed-off-by: Davidlohr Bueso <davidlohr@hp.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'dt-bus-name' into for-nextRob Herring2014-05-13
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| * ARC: !PREEMPT: Ensure Return to kernel mode is IRQ safeVineet Gupta2014-04-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a very small race window where resume to kernel mode from a Exception Path (or pure kernel mode which is true for most of ARC exceptions anyways), was not disabling interrupts in restore_regs, clobbering the exception regs Anton found the culprit call flow (after many sleepless nights) | 1. we got a Trap from user land | 2. started to service it. | 3. While doing some stuff on user-land memory (I think it is padzero()), | we got a DataTlbMiss | 4. On return from it we are taking "resume_kernel_mode" path | 5. NEED_RESHED is not set, so we go to "return from exception" path in | restore regs. | 6. there seems to be IRQ happening Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: <stable@vger.kernel.org> #3.10, 3.12, 3.13, 3.14 Cc: Anton Kolesov <Anton.Kolesov@synopsys.com> Cc: Francois Bedard <Francois.Bedard@synopsys.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | of/fdt: update of_get_flat_dt_prop in prep for libfdtRob Herring2014-04-30
|/ | | | | | | | | | | Make of_get_flat_dt_prop arguments compatible with libfdt fdt_getprop call in preparation to convert FDT code to use libfdt. Make the return value const and the property length ptr type an int. Signed-off-by: Rob Herring <robh@kernel.org> Tested-by: Michal Simek <michal.simek@xilinx.com> Tested-by: Grant Likely <grant.likely@linaro.org> Tested-by: Stephen Chivers <schivers@csc.com>
* ARC: [SMP] General FixesVineet Gupta2014-04-05
| | | | | | | -Pass the expected arg to non-boot park'ing routine (It worked so far because existing SMP backends don't use the arg) -CONFIG_DEBUG_PREEMPT warning
* ARC: [clockevent] simplify timer ISRVineet Gupta2014-03-26
| | | | | | * Remove one liner IRQ ACK accessor, it was coming in the way of readability. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [clockevent] can't be SoC specificVineet Gupta2014-03-26
| | | | | | So no point keeping it weak Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: switch to generic ENTRY/END assembler annotationsVineet Gupta2014-03-26
| | | | | | | | With commit 9df62f054406 "arch: use ASM_NL instead of ';'" the generic macros can handle the arch specific newline quirk. Hence we can get rid of ARC asm macros and use the "C" style macros. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [cmdline] support External Device Trees from u-bootVineet Gupta2014-01-16
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [cmdline] uboot cmdline handling reworkVineet Gupta2014-01-16
| | | | | | | | | | * Moved cmdline copy from asm to "C" - allows for more robust checking of pointer validity etc. * Remove the Kconfig option to do so, base it on a runtime value passed by u-boot Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [SMP] optimize IPI send and receiveVineet Gupta2013-12-23
| | | | | | | | | | | * Don't send an IPI if receiver already has a pending IPI. Atomically piggyback the new msg with pending msg. * IPI receiver looping on xchg() not required References: https://lkml.org/lkml/2013/11/25/232 Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [SMP] simplify IPI codeVineet Gupta2013-12-23
| | | | | | * ipi_data is just a word, no need to keep it as struct * find_next_bit() not needed to loop thru a 32bit word, ffs suffices
* ARC: [SMP] cpu halt interface doesn't need "self" cpu-idVineet Gupta2013-12-23
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [SMP] IPI ACK interface doesn't need "self" cpu-idVineet Gupta2013-12-23
| | | | | | | | The interface is confusing, it feels like we are getting "sender" info, whereas it is the "receiver", which can very well be retrived by smp_processor_id(), if need be. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [SMP] cpumask not needed in IPI send pathVineet Gupta2013-12-23
| | | | | | | | | | | | | | | The current IPI sending callstack needlessly involves cpumask. arch_send_call_function_single_ipi(cpu) / smp_send_reschedule(cpu) ipi_send_msg(cpumask_of(cpu)) --> [cpu to cpumask] plat_smp_ops.ipi_send(callmap) for_each_cpu(callmap) --> [cpuask to cpu] do_plat_specific_ipi_PER_CPU Given that current backends are not capable of 1:N IPIs, lets simplify the interface for now, by keeping "a" cpu all along. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [perf] Fix a few thinkosVineet Gupta2013-11-28
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* Merge tag 'arc-v3.13-rc1-part2' of ↵Linus Torvalds2013-11-19
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc Pull second set of ARC changes from Vineet Gupta: - Support for Perf from Mischa - Enabling GPIO/Pinctrl drivers for Abilis TB10x platform - New defconfig for buildroot * tag 'arc-v3.13-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARC: [plat-arcfpga] Add defconfig without initramfs location ARC: perf: ARC 700 PMU doesn't support sampling events ARC: Add documentation on DT binding for ARC700 PMU ARC: Add perf support for ARC700 cores ARC: [TB10x] Updates for GPIO and pinctrl
| * ARC: perf: ARC 700 PMU doesn't support sampling eventsMischa Jonker2013-11-15
| | | | | | | | | | | | | | | | | | | | | | | | The ARC 700 does not have an interrupt associated with it, and as such it cannot trigger when a counter overflows. As the counters are 48 bit, it will usually take at least 100 days before a counter overflows, so for mere counting of events, there is no problem. Sampling is not supported though. Signed-off-by: Mischa Jonker <mjonker@synopsys.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: Add perf support for ARC700 coresMischa Jonker2013-11-11
| | | | | | | | | | | | | | | | | | This adds basic perf support for ARC700 cores. Most PERF_COUNT_HW* events are supported now. Signed-off-by: Mischa Jonker <mjonker@synopsys.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-11-15
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "Usual earth-shaking, news-breaking, rocket science pile from trivial.git" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits) doc: usb: Fix typo in Documentation/usb/gadget_configs.txt doc: add missing files to timers/00-INDEX timekeeping: Fix some trivial typos in comments mm: Fix some trivial typos in comments irq: Fix some trivial typos in comments NUMA: fix typos in Kconfig help text mm: update 00-INDEX doc: Documentation/DMA-attributes.txt fix typo DRM: comment: `halve' -> `half' Docs: Kconfig: `devlopers' -> `developers' doc: typo on word accounting in kprobes.c in mutliple architectures treewide: fix "usefull" typo treewide: fix "distingush" typo mm/Kconfig: Grammar s/an/a/ kexec: Typo s/the/then/ Documentation/kvm: Update cpuid documentation for steal time and pv eoi treewide: Fix common typo in "identify" __page_to_pfn: Fix typo in comment Correct some typos for word frequency clk: fixed-factor: Fix a trivial typo ...
| * | doc: typo on word accounting in kprobes.c in mutliple architecturesAnoop Thomas Mathew2013-10-14
| | | | | | | | | | | | | | | Signed-off-by: Anoop Thomas Mathew <atm@profoundis.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | Merge tag 'devicetree-for-3.13' of ↵Linus Torvalds2013-11-12
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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() ...
| * \ \ Merge remote-tracking branch 'grant/devicetree/next' into for-nextRob Herring2013-11-07
| |\ \ \ | | | |/ | | |/|
| * | | arc: remove unnecessary prom.h includesRob Herring2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | arc: use common of_flat_dt_match_machineRob Herring2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | arc: use early_init_dt_scanRob Herring2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | arc: use unflatten_and_copy_device_treeRob Herring2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | smp, ARC: kill SMP single function call interruptJiang Liu2013-11-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | ARC: [SMP] Disallow RTSCVineet Gupta2013-11-07
| | | | | | | | | | | | | | | | | | | | | | | | RTSC is strictly incore and must not be allowed in SMP configs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | | | ARC: [SMP] Fix build failures for large NR_CPUSVineet Gupta2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | ARC: [SMP] TLB flushVineet Gupta2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - 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>
* | | | arc: export symbol for pm_power_off in reset.cChen Gang2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | arc: export symbol for save_stack_trace() in stacktrace.cChen Gang2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | arc: remove '__init' for get_hw_config_num_irq()Chen Gang2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | arc: remove '__init' for first_lines_of_secondary()Chen Gang2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | arc: kgdb: add default implementation for kgdb_roundup_cpus()Chen Gang2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | ARC: Add support for irqflags tracing and lockdepVineet Gupta2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | ARC: Reset the value of Interrupt Priority RegisterVineet Gupta2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | ARC: Reduce #ifdef'ery for unaligned access emulationVineet Gupta2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | ARC: Change calling convention of do_page_fault()Vineet Gupta2013-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | ARC: use __weak instead of __attribute__((weak))Vineet Gupta2013-11-06
| | | | | | | | | | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | | | ARC: Annotate some functions as staticVineet Gupta2013-11-06
| | | | | | | | | | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | | | arc: Replace __get_cpu_var usesChristoph Lameter2013-11-06
| |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __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>
* | | ARC: Ignore ptrace SETREGSET request for synthetic register "stop_pc"Vineet Gupta2013-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
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