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* arc: SMP: CONFIG_ARC_IPI_DBG cleanupValentin Rothberg2016-02-241-5/+0
| | | | | | | | | Previous Commit ("ARC: SMP: No need for CONFIG_ARC_IPI_DBG") removed the Kconfig option ARC_IPI_DBG. Remove the last reference on this option. Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: SMP: No need for CONFIG_ARC_IPI_DBGVineet Gupta2016-02-243-19/+1
| | | | | | | | This was more relevant during SMP bringup. The warning for bogus msg better be visible always. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: Elide sending new cross core intr if receiver didn't ack prevVineet Gupta2016-02-241-17/+10
| | | | | | | | | | | | | | | | | ARConnect/MCIP IPI sending has a retry-wait loop in case caller had not seen a previous such interrupt. Turns out that it is not needed at all. Linux cross core calling allows coalescing multiple IPIs to same receiver - it is fine as long as there is one. This logic is built into upper layer already, at a higher level of abstraction. ipi_send_msg_one() sets the actual msg payload, but it only calls MCIP IPI sending if msg holder was empty (using atomic-set-new-and-get-old construct). Thus it is unlikely that the retry-wait looping was ever getting exercised at all. Cc: Chuck Jordan <cjordan@synopsys.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: SMP: Push IPI_IRQ into IPI providerVineet Gupta2016-02-242-1/+1
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [intc-compact] Remove IPI setup from ARCompact portVineet Gupta2016-02-242-4/+0
| | | | | | | | There is no real ARC700 based SMP SoC so remove IPI definition. EZChip's SMP ARC700 is going to use a different intc and IPI provider anyways. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: SMP: Emulate IPI to self using software triggered interruptVineet Gupta2016-02-243-5/+32
| | | | | | | | | | | | | | | | | | | | | | | | ARConnect/MCIP Inter-Core-Interrupt module can't send interrupt to local core. So use core intc capability to trigger software interrupt to self, using an unsued IRQ #21. This showed up as csd deadlock with LTP trace_sched on a dual core system. This test acts as scheduler fuzzer, triggering all sorts of schedulting activity. Trouble starts with IPI to self, which doesn't get delivered (effectively lost due to H/w capability), but the msg intended to be sent remain enqueued in per-cpu @ipi_data. All subsequent IPIs to this core from other cores get elided due to the IPI coalescing optimization in ipi_send_msg_one() where a pending msg implies an IPI already sent and assumes other core is yet to ack it. After the elided IPI, other core simply goes into csd_lock_wait() but never comes out as this core never sees the interrupt. Fixes STAR 9001008624 Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> [4.2] Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* arc: get rid of DEVTMPFS dependency on INITRAMFS_SOURCEAlexey Brodkin2016-02-2311-57/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Even though DEVTMPFS is required when our pre-built initramfs is used it is not the case in general. It is perfectly possible to use initramfs with device nodes already populated or there could be other usages, see discussion below for more detials: http://thread.gmane.org/gmane.comp.embedded.openwrt.devel/37819/focus=37821 This change removes mentioned dependency from arch/arc/Kconfig updating instead those defconfigs that are usually used with this kind of pre-build initramfs. And while at it all touched defconfigs were regenerated via savedefconfig and some options were removed: * USB is selected by other options implicitly * VGA_CONSOLE is disableb for ARC since 031e29b5877f31676739dc2f847d04c2c0732034 * EXT3_FS automatically selects EXT4_FS * MTDxxx and JFFS2_FS make no sense for AXS because AXS NAND controller is not upstreamed * NET_OSCI_LAN is not in upstream as well * ARCPGU_xxx options make no sense because ARC PGU is not yet in upstream and when it gets there all config options would be taken from devicetree Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: boot report CCMs (Closely Coupled Memories)Vineet Gupta2016-02-182-40/+70
| | | | | | | | | - ARCv2 uses a seperate BCR for {I,D}CCM base address: ARCompact encoded both base/size in same BCR - Size encoding in common BCR is different for ARCompact/ARCv2 Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: boot print Low Latency MemoryVineet Gupta2016-02-181-1/+2
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: Assume multiplier is always presentVineet Gupta2016-02-183-14/+0
| | | | | | | | It is unlikely that designs running Linux will not have multiplier. Further the current support is not complete as tool don't generate a multilib w/o multiplier. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* Merge tag 'arc-4.5-fixes' of ↵Linus Torvalds2016-02-1311-61/+119
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc Pull ARC fixes from Vineet Gupta: "I've been sitting on some of these fixes for a while. - Corner case of returning to delay slot from interrupt - Changing default interrupt prioiry level - Kconfig'ize support for super pages - Other minor fixes" * tag 'arc-4.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARC: mm: Introduce explicit super page size support ARCv2: intc: Allow interruption by lowest priority interrupt ARCv2: Check for LL-SC livelock only if LLSC is enabled ARC: shrink cpuinfo by not saving full timer BCR ARCv2: clocksource: Rename GRTC -> GFRC ... ARCv2: STAR 9000950267: Handle return from intr to Delay Slot #2
| * ARC: mm: Introduce explicit super page size supportVineet Gupta2016-02-122-19/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MMUv4 supports 2 concurrent page sizes: Normal and Super [4K to 16M] So far Linux supported a single super page size for a given Normal page, depending on the software page walking address split. e.g. we had 11:8:13 address split for 8K page, which meant super page was 2 ^(8+13) = 2M (given that THP size has to be PMD_SHIFT) Now we turn this around, by allowing multiple Super Pages in Kconfig (currently 2M and 16M only) and forcing page walker address split to PGDIR_SHIFT and PAGE_SHIFT For configs without Super page, things are same as before and PGDIR_SHIFT can be hacked to get non default address split The motivation for this change is a customer who needs 16M super page and a 8K Normal page combo. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARCv2: intc: Allow interruption by lowest priority interruptVineet Gupta2016-02-102-19/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ARC HS Cores support configurable multiple interrupt priorities of upto 16 levels. There is processor "interrupt preemption threshhold" in STATUS32.E[4:1] And several places need to set this up: 1. seed value as kernel is booting 2. seed value for user space programs 3. Arg to SLEEP instruction in idle task (what interrupt prio can wake) 4. Per-IRQ line prioirty (i.e. what is the priority of interrupt raised by a peripheral or timer or perf counter... Currently above sites use the highest priority 0. This can be potential problem when multiple priorities are supported. e.g. user space could only be interrupted by P0 interrupt, not others... So turn this over and instead make default interruption level to be the lowest priority possible 15. This should be fine even if there are fewer priority levels configured (say two: P0 HIGH, P1 LOW) This feature also effectively disables FIRQ feature if present in hardware config. With old code, a P0 interrupt would be FIRQ, needing special handling (ISR or Register Banks) which is NOT supported yet. Now it not be P0 (P15 or whatever is lowest prio) so FIRQ is not triggered. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARCv2: Check for LL-SC livelock only if LLSC is enabledVineet Gupta2016-01-291-0/+1
| | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: shrink cpuinfo by not saving full timer BCRVineet Gupta2016-01-292-9/+13
| | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARCv2: clocksource: Rename GRTC -> GFRC ...Vineet Gupta2016-01-295-13/+13
| | | | | | | | | | | | ... it is now called Global Free Running Counter Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARCv2: STAR 9000950267: Handle return from intr to Delay Slot #2Vineet Gupta2016-01-221-1/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Returning to delay slot, riding an interrupti, had one loose end. AUX_USER_SP used for restoring user mode SP upon RTIE was not being setup from orig task's saved value, causing task to use wrong SP, leading to ProtV errors. The reason being: - INTERRUPT_EPILOGUE returns to a kernel trampoline, thus not expected to restore it - EXCEPTION_EPILOGUE is not used at all Fix that by restoring AUX_USER_SP explicitly in the trampoline. This was broken in the original workaround, but the error scenarios got reduced considerably since v3.14 due to following: 1. The Linuxthreads.old based userspace at the time caused many more exceptions in delay slot than the current NPTL based one. Infact with current userspace the error doesn't happen at all. 2. Return from interrupt (delay slot or otherwise) doesn't get exercised much after commit 4de0e52867d8 ("Really Re-enable interrupts to avoid deadlocks") since IRQ_ACTIVE.active being clear means most returns are as if from pure kernel (even for active interrupts) Infact the issue only happened in an experimental branch where I was tinkering with reverted 4de0e52867d8 Cc: stable@kernel.org # v4.2+ Fixes: 4255b07f2c9c ("ARCv2: STAR 9000793984: Handle return from intr to Delay Slot") Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | dma-mapping: always provide the dma_map_ops based implementationChristoph Hellwig2016-01-212-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the generic implementation to <linux/dma-mapping.h> now that all architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now that everyone supports them. [valentinrothberg@gmail.com: remove leftovers in Kconfig] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Helge Deller <deller@gmx.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Steven Miao <realmz6@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | arc: convert to dma_map_opsChristoph Hellwig2016-01-213-230/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | [vgupta@synopsys.com: ARC: dma mapping fixes #2] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Carlos Palminha <CARLOS.PALMINHA@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Kconfig: remove HAVE_LATENCYTOP_SUPPORTWill Deacon2016-01-161-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As illustrated by commit a3afe70b83fd ("[S390] latencytop s390 support."), HAVE_LATENCYTOP_SUPPORT is defined by an architecture to advertise an implementation of save_stack_trace_tsk. However, as of 9212ddb5eada ("stacktrace: provide save_stack_trace_tsk() weak alias") a dummy implementation is provided if STACKTRACE=y. Given that LATENCYTOP already depends on STACKTRACE_SUPPORT and selects STACKTRACE, we can remove HAVE_LATENCYTOP_SUPPORT altogether. Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: James Hogan <james.hogan@imgtec.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Helge Deller <deller@gmx.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: differentiate page_mapped() from page_mapcount() for compound pagesKirill A. Shutemov2016-01-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's define page_mapped() to be true for compound pages if any sub-pages of the compound page is mapped (with PMD or PTE). On other hand page_mapcount() return mapcount for this particular small page. This will make cases like page_get_anon_vma() behave correctly once we allow huge pages to be mapped with PTE. Most users outside core-mm should use page_mapcount() instead of page_mapped(). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2016-01-151-2/+2
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull livepatching updates from Jiri Kosina: - RO/NX attribute fixes for patch module relocations from Josh Poimboeuf. As part of this effort, module.c has been cleaned up as well and livepatching is piggy-backing on this cleanup. Rusty is OK with this whole lot going through livepatching tree. - symbol disambiguation support from Chris J Arges. That series is also Reviewed-by: Miroslav Benes <mbenes@suse.cz> but this came in only after I've alredy pushed out. Didn't want to rebase because of that, hence I am mentioning it here. - symbol lookup fix from Miroslav Benes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: Cleanup module page permission changes module: keep percpu symbols in module's symtab module: clean up RO/NX handling. module: use a structure to encapsulate layout. gcov: use within_module() helper. module: Use the same logic for setting and unsetting RO/NX livepatch: function,sympos scheme in livepatch sysfs directory livepatch: add sympos as disambiguator field to klp_reloc livepatch: add old_sympos as disambiguator field to klp_func
| * module: use a structure to encapsulate layout.Rusty Russell2015-12-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Makes it easier to handle init vs core cleanly, though the change is fairly invasive across random architectures. It simplifies the rbtree code immediately, however, while keeping the core data together in the same cachline (now iff the rbtree code is enabled). Acked-by: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | ARC: dw2 unwind: Catch Dwarf SNAFUs earlyVineet Gupta2015-12-211-4/+8
| | | | | | | | | | | | | | Instead of seeing empty stack traces, let kernel fail early so dwarf issues can be fixed sooner Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: dw2 unwind: Don't bail for CIE.version != 1Vineet Gupta2015-12-211-6/+1
| | | | | | | | | | | | | | The rudimentary CIE.version == 3 handling is already present in code (for return address register specification) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | Revert "ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing"Vineet Gupta2015-12-211-9/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Blingly ignoring CIE.version != 1 was a bad idea. It still leaves "desirability" when running perf with callgraphing where libgcc symbols might show in hotspot. More importantly, basic CIE.version == 3 support already exists in code: | | retAddrReg = state.version <= 1 ? *ptr++ : get_uleb128(&ptr, end); | Next commit with simply add continue-not-bail for CIE.version != 1 This reverts commit 323f41f9e7d0cb5b1d1586aded6682855f1e646d.
* | ARC: Fix linking errors with CONFIG_MODULE + CONFIG_CC_OPTIMIZE_FOR_SIZEVineet Gupta2015-12-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At -Os, ARC gcc generates millicode thunk for function prologue/epilogue, which are served by libgcc. Modules historically are NOT linked with libgcc to avoid code bloat, reducing runtime relocation fixups etc. I even once tried doing that but got lost in makefile intricacies. This means modules at -Os don't get the millicode thunks, causing build failures below: | MODPOST 5 modules | ERROR: "__ld_r13_to_r18" [crypto/sha256_generic.ko] undefined! | ERROR: "__ld_r13_to_r18_ret" [crypto/sha256_generic.ko] undefined! | ERROR: "__st_r13_to_r18" [crypto/sha256_generic.ko] undefined! | ERROR: "__ld_r13_to_r17_ret" [crypto/sha256_generic.ko] undefined! | ERROR: "__st_r13_to_r17" [crypto/sha256_generic.ko] undefined! | ERROR: "__ld_r13_to_r16_ret" [crypto/sha256_generic.ko] undefined! | ERROR: "__st_r13_to_r16" [crypto/sha256_generic.ko] undefined! |.... |.... Workaround that by inhibiting millicode thunks for loadable modules Fixes STAR 9000641864: ("Linux built with optimizations for size emits errors for modules") Reported-by: Anton Kolesov <akolesov@synosys.com> Cc: Michal Marek <mmarek@suse.cz> Cc: linux-kernel@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: mm: fix building for MMU v2Alexey Brodkin2015-12-211-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ARC700 cores with MMU v2 don't have IC_PTAG AUX register and so we only define ARC_REG_IC_PTAG for MMU versions >= 3. But current implementation of cache_line_loop_vX() routines assumes availability of all of them (v2, v3 and v4) simultaneously. And given undefined ARC_REG_IC_PTAG if CONFIG_MMU_VER=2 we're seeing compilation problem: ---------------------------------->8------------------------------- CC arch/arc/mm/cache.o arch/arc/mm/cache.c: In function '__cache_line_loop_v3': arch/arc/mm/cache.c:270:13: error: 'ARC_REG_IC_PTAG' undeclared (first use in this function) aux_tag = ARC_REG_IC_PTAG; ^ arch/arc/mm/cache.c:270:13: note: each undeclared identifier is reported only once for each function it appears in scripts/Makefile.build:258: recipe for target 'arch/arc/mm/cache.o' failed ---------------------------------->8------------------------------- The simples fix is to have ARC_REG_IC_PTAG defined regardless MMU version being used. We don't use it in cache_line_loop_v2() anyways so who cares. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: mm: HIGHMEM: Fix section mismatch splatVineet Gupta2015-12-211-2/+2
| | | | | | | | | | | | | | | | | | | WARNING: vmlinux.o(.text+0xd6c2): Section mismatch in reference from the function alloc_kmap_pgtable() to the function | .init.text:__alloc_bootmem_low() The function alloc_kmap_pgtable() references the function __init __alloc_bootmem_low(). This is often because alloc_kmap_pgtable lacks a __init annotation or the annotation of __alloc_bootmem_low is wrong. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: smp: Rename platform hook @init_cpu_smp -> @init_per_cpuVineet Gupta2015-12-173-6/+6
| | | | | | | | | | | | Makes it similar to smp_ops which also has callback with same name Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: rename smp operation init_irq_cpu() to init_per_cpu()Noam Camus2015-12-174-7/+7
| | | | | | | | | | | | | | | | | | This will better reflect its description i.e. "any needed setup..." and not just do an "IPI request". Signed-off-by: Noam Camus <noamc@ezchip.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailingVineet Gupta2015-12-171-4/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ARC dwarf unwinder only supports CIE version == 1 The boot time dwarf sanitizer (part of binary lookup table constructor) would simply bail if it saw CIE version == 3, rendering unwinder with a NULL lookup table. It seems libgcc linked with kernel does have such entries. With fallback linear search removed, and a NULL binary lookup table, unwinder fails to generate any stack trace. So allow graceful ignoring of unsupported CIE entries. This problem was initially seen in Alexey's setup (and not mine) as he was using buildroot built toolchain (libgcc) which doesn't get built with CFLAGS_FOR_TARGET="-gdwarf-2 which is my default Fixes STAR 9000985048: "kernel unwinder broken with stock tools" Fixes: 2e22502c080f ARC: dw2 unwind: Remove falllback linear search thru FDE entries Reported-by Alexey Brodkin <abrodkin@synopsys.com> Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: dw2 unwind: Reinstante unwinding out of modulesVineet Gupta2015-12-173-19/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fix which removed linear searching of dwarf (because binary lookup data always exists) missed out on the fact that modules don't get the binary lookup tables info. This caused unwinding out of modules to stop working. So add binary lookup header setup (equivalent of eh_frame_hdr setup) to modules as well. While at it, confine the header setup to within unwinder code, reducing one API exposed out of unwinder code. Fixes: 2e22502c080f ARC: dw2 unwind: Remove falllback linear search thru FDE entries Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: [plat-sim] unbork non default CONFIG_LINUX_LINK_BASEVineet Gupta2015-12-173-2/+6
| | | | | | | | | | | | | | | | | | | | | | HIGHMEM support bumped the default memory size for nsim platform to 1G. Thus total memory ended at the very edge of start of peripherals address space. With linux link base shifted, memory started bleeding into peripheral space which caused early boot bad_page spew ! Fixes: 29e332261d2 ("ARC: mm: HIGHMEM: populate high memory from DT") Reported-by: Anton Kolesov <akolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: intc: Document arc_request_percpu_irq() betterVineet Gupta2015-12-121-0/+12
| | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARCv2: perf: Ensure perf intr gets enabled on all coresVineet Gupta2015-12-121-23/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This was the second perf intr issue perf sampling on multicore requires intr to be enabled on all cores. ARC perf probe code used helper arc_request_percpu_irq() which calls - request_percpu_irq() on core0 - enable_percpu_irq() on all all cores (including core0) genirq requires that request be made ahead of enable call. However if perf probe happened on non core0 (observed on a 3.18 kernel), enable would get called ahead of request, failing obviously and rendering perf intr disabled on all such cores [ 11.120000] 1 ARC perf : 8 counters (48 bits), 113 conditions, [overflow IRQ support] [ 11.130000] 1 -----> enable_percpu_irq() IRQ 20 failed [ 11.140000] 3 -----> enable_percpu_irq() IRQ 20 failed [ 11.140000] 2 -----> enable_percpu_irq() IRQ 20 failed [ 11.140000] 0 =====> request_percpu_irq() IRQ 20 [ 11.140000] 0 -----> enable_percpu_irq() IRQ 20 Fix this fragility, by calling request_percpu_irq() on whatever core calls probe (there is no requirement on which core calls this anyways) and then calling enable on each cores. Interestingly this started as invesigation of STAR 9000838902: "sporadically IRQs enabled on perf prob" which was about occassional boot spew as request_percpu_irq got called non-locally (from an IPI), and re-enabled interrupts in following path proc_mkdir -> spin_unlock_irq() which the irq work code didn't like. | ARC perf : 8 counters (48 bits), 113 conditions, [overflow IRQ support] | | BUG: failure at ../kernel/irq_work.c:135/irq_work_run_list()! | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.18.10-01127-g285efb8e66d1 #2 | | Stack Trace: | arc_unwind_core.constprop.1+0x94/0x104 | dump_stack+0x62/0x98 | irq_work_run_list+0xb0/0xb4 | irq_work_run+0x22/0x3c | do_IPI+0x74/0x9c | handle_irq_event_percpu+0x34/0x164 | handle_percpu_irq+0x58/0x78 | generic_handle_irq+0x1e/0x2c | arch_do_IRQ+0x3c/0x60 | ret_from_exception+0x0/0x8 Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: Alexey Brodkin <abrodkin@synopsys.com> Cc: <stable@vger.kernel.org> #4.2+ Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: intc: No need to clear IRQ_NOAUTOENVineet Gupta2015-12-121-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arc_request_percpu_irq() is called by all cores to request/enable percpu irq. It has some "prep" calls needed by genirq: - setup percpu devid - disable IRQ_NOAUTOEN However given that enable_percpu_irq() is called enayways, latter can be avoided. We are now left with irq_set_percpu_devid() quirk and that too for ARCompact builds only, since previous patch updated ARCv2 intc to do this in the "right" place, i.e. irq map function. By next release, this will ultimately be fixed for ARCompact as well. Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexey Brodkin <abrodkin@synopsys.com> Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARCv2: intc: Fix random perf irq disabling in SMP setupVineet Gupta2015-12-121-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As part of fixing another perf issue, observed that after a perf run, the interrupt got disabled on one/more cores. Turns out that despite requesting perf irq as percpu, the flow handler registered was not handle_percpu_irq() Given that on ARCv2 cores, IRQs < 24 are always private to cpu, we register the right handler at the very onset. Before Fix | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 0 0 0 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 522 8 51916 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 522 8 104368 ARCv2 core Intc 20 ARC perf counters After Fix | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 0 0 0 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 64198 62012 62697 67803 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 126014 122792 123301 133654 ARCv2 core Intc 20 ARC perf counters Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Alexey Brodkin <abrodkin@synopsys.com> Cc: stable@vger.kernel.org #4.2+ Cc: linux-kernel@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: [axs10x] cap ethernet phy to 100 Mbit/secAlexey Brodkin2015-12-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | Current ARC SDP boards cannot reliably handle 1Gbit Ethernet connections due to limitations in hardware. To make sure networking is stable on the board we're limiting phy to 100 Mbit. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: dw2 unwind: Remove falllback linear search thru FDE entriesVineet Gupta2015-11-231-33/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes STAR 9000953410: "perf callgraph profiling causing RCU stalls" | perf record -g -c 15000 -e cycles /sbin/hackbench | | INFO: rcu_preempt self-detected stall on CPU | 1: (1 GPs behind) idle=609/140000000000002/0 softirq=2914/2915 fqs=603 | Task dump for CPU 1: in-kernel dwarf unwinder has a fast binary lookup and a fallback linear search (which iterates thru each of ~11K entries) thus takes 2 orders of magnitude longer (~3 million cycles vs. 2000). Routines written in hand assembler lack dwarf info (as we don't support assembler CFI pseudo-ops yet) fail the unwinder binary lookup, hit linear search, failing nevertheless in the end. However the linear search is pointless as binary lookup tables are created from it in first place. It is impossible to have binary lookup fail while succeed the linear search. It is pure waste of cycles thus removed by this patch. This manifested as RCU stalls / NMI watchdog splat when running hackbench under perf with callgraph profiling. The triggering condition was perf counter overflowing in routine lacking dwarf info (like memset) leading to patheic 3 million cycle unwinder slow path and by the time it returned new interrupts were already pending (Timer, IPI) and taken rightaway. The original memset didn't make forward progress, system kept accruing more interrupts and more unwinder delayes in a vicious feedback loop, ultimately triggering the NMI diagnostic. Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: remove SYNC from __switch_to()Vineet Gupta2015-11-172-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SYNC in __switch_to() is a historic relic and not needed at all. - In UP context it is obviously useless, why would we want to stall the core for all updates to stack memory of t0 to complete before loading kernel mode callee registers from t1 stack's memory. - In SMP, there could be potential race in which outgoing task could be concurrently picked for running on a different core, thus writes to stack here need to be visible before the reads from stack on other core. Peter confirmed that generic schedular already has needed barriers (by way of rq lock) so there is no need for additional arch barrier. This came up when Noam was trying to replace this SYNC with EZChip specific hardware thread scheduling instruction for their platform support. Link: http://lkml.kernel.org/r/20151102092654.GM17308@twins.programming.kicks-ass.net Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Cc: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARCv2: Use the default irq priority for idle sleepVineet Gupta2015-11-161-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Although kernel doesn't support the multiple IRQ priority levels provided by HS38x core intc yet, ensure that the default prio value is used anyways by relevant code. SLEEP insn needs to be provided the IRQ priority level which can interrupt it. This needs to be the default level which maynot necessarily be 0 as assumed by current code. This change allows a kernel with ARCV2_IRQ_DEF_PRIO = 1 to boot fine. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: Abstract out ISA specific SLEEP argsVineet Gupta2015-11-163-5/+8
| | | | | | | | | | | | No semantical changes, prepares for ARCv2 specific change in next commit Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: comments updateVineet Gupta2015-11-161-2/+2
| | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* | ARC: switch to arc-linux- CROSS_COMPILE prefix across all configssujayraaj2015-11-169-9/+9
|/ | | | | | | | | | | | | | When building kernel with buildroot built toolchain, CROSS_COMPILE currently needs adjustment even if minor. This is because the defconfigs prefer "arc-linux-uclibc-" prefix from hand built (non buildroot) toolchain while buildroot provides "arc-buildroot-linux-uclibc-" To avoid this use the common "arc-linux-" prefix which is provided by buildroot and has also been in hand built tools for quite some time. Signed-off-by: sujayraaj <sujayraaj@gmail.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: updated changelog]
* Merge tag 'arc-4.4-rc1-part2' of ↵Linus Torvalds2015-11-147-55/+73
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc Pull ARC fixes from Vineet Gupta: "Found a couple of brown paper bag bugs with the prev pull request (including a SMP build breakage report from Guenter). Since these are urgent I also decided to send over a bunch of other pending fixes which could have otherwise waited an rc or two. Summary: - A bunch of brown paper bag bugs (MAINTAINERS list email, SMP build failure) - cpu_relax() now compiler barrier for UP as well - handling of userspace Bus Errors for ARCompact builds" * tag 'arc-4.4-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARC: Fix silly typo in MAINTAINERS file ARC: cpu_relax() to be compiler barrier even for UP ARC: use ASL assembler mnemonic ARC: [arcompact] Handle bus error from userspace as Interrupt not exception ARC: remove extraneous header include ARCv2: lib: memcpy: use local symbols
| * ARC: cpu_relax() to be compiler barrier even for UPVineet Gupta2015-11-141-4/+0
| | | | | | | | | | | | | | | | | | | | cpu_relax() on ARC has been barrier only for SMP (and no-op for UP). Per recent discussions, it is safer to make it a compiler barrier unconditionally. Link: http://lkml.kernel.org/r/53A7D3AA.9020100@synopsys.com Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: use ASL assembler mnemonicVineet Gupta2015-11-141-3/+3
| | | | | | | | | | | | | | | | | | ARCompact and ARCv2 only have ASL, while binutils used to support LSL as a alias mnemonic. Newer binutils (upstream) don't want to do that so replace it. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: [arcompact] Handle bus error from userspace as Interrupt not exceptionVineet Gupta2015-11-143-21/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bus errors from userspace on ARCompact based cores are handled by core as a high priority L2 interrupt but current code treated it as interrupt Handling an interrupt like exception is certainly not going to go unnoticed. (and it worked so far as we never saw a Bus error from userspace until IPPK guys tested a DDR controller with ECC error detection etc hence needed to explicitly trigger/handle such errors) - So move mem_service exception handler from common code into ARCv2 code. - In ARCompact code, define mem_service as L2 interrupt handler which just drops down to pure kernel mode and goes of to enqueue SIGBUS Reported-by: Nelson Pereira <npereira@synopsys.com> Tested-by: Ana Martins <amartins@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| * ARC: remove extraneous header includeVineet Gupta2015-11-141-1/+0
| | | | | | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>