summaryrefslogtreecommitdiff
path: root/arch/tile/include/asm
AgeCommit message (Collapse)Author
2014-02-13tile: remove compat_sys_lookup_dcookie declaration to fix compile errorHeiko Carstens
commit 5a5e75f4714a592f31e57f248b8f5c866f278b8d upstream. With commit d8d14bd09cdd ("fs/compat: fix lookup_dcookie() parameter handling") I changed the type of the len parameter of the lookup_dcookie() syscall. However I missed that there was still a stale declaration in arch/tile/.. which now causes a compile error on tile: In file included from fs/dcookies.c:28:0: include/linux/compat.h:425:17: error: conflicting types for 'compat_sys_lookup_dcookie' fs/dcookies.c:207:1: error: conflicting types for 'compat_sys_lookup_dcookie' Simply remove the declaration in the tile architecture, which is only a leftover from before the different compat lookup_dcookie() versions have been merged. The correct declaration is now in include/linux/compat.h The build error was reported by Fenguang's build bot. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-30tile: use a more conservative __my_cpu_offset in CONFIG_PREEMPTChris Metcalf
It turns out the kernel relies on barrier() to force a reload of the percpu offset value. Since we can't easily modify the definition of barrier() to include "tp" as an output register, we instead provide a definition of __my_cpu_offset as extended assembly that includes a fake stack read to hazard against barrier(), forcing gcc to know that it must reread "tp" and recompute anything based on "tp" after a barrier. This fixes observed hangs in the slub allocator when we are looping on a percpu cmpxchg_double. A similar fix for ARMv7 was made in June in change 509eb76ebf97. Cc: stable@vger.kernel.org Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-27tile: include: asm: use 'long long' instead of 'u64' for atomic64_t and its ↵Chen Gang
related functions atomic* value is signed value, and atomic* functions need also process signed value (parameter value, and return value), so use 'long long' instead of 'u64'. After replacement, it will also fix a bug for atomic64_add_negative(): "u64 is never less than 0". The modifications are: in vim, use "1,% s/\<u64\>/long long/g" command. remove redundant '__aligned(8)'. be sure of 80 (and macro '\') columns limitation after replacement. Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [re-instated const cast]
2013-09-13tile: remove HUGE_VMAP dead codeChris Metcalf
A config option to allow a variant vmap() using huge pages that was never upstreamed had some bits of code related to it scattered around the tile architecture; the config option was removed downstream and this commit cleans up the scattered evidence of it from the upstream as well. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds
Pull Tile arch updates from Chris Metcalf: "These changes bring in a bunch of new functionality that has been maintained internally at Tilera over the last year, plus other stray bits of work that I've taken into the tile tree from other folks. The changes include some PCI root complex work, interrupt-driven console support, support for performing fast-path unaligned data fixups by kernel-based JIT code generation, CONFIG_PREEMPT support, vDSO support for gettimeofday(), a serial driver for the tilegx on-chip UART, KGDB support, more optimized string routines, support for ftrace and kprobes, improved ASLR, and many bug fixes. We also remove support for the old TILE64 chip, which is no longer buildable" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: (85 commits) tile: refresh tile defconfig files tile: rework <asm/cmpxchg.h> tile PCI RC: make default consistent DMA mask 32-bit tile: add null check for kzalloc in tile/kernel/setup.c tile: make __write_once a synonym for __read_mostly tile: remove support for TILE64 tile: use asm-generic/bitops/builtin-*.h tile: eliminate no-op "noatomichash" boot argument tile: use standard tile_bundle_bits type in traps.c tile: simplify code referencing hypervisor API addresses tile: change <asm/system.h> to <asm/switch_to.h> in comments tile: mark pcibios_init() as __init tile: check for correct compiler earlier in asm-offsets.c tile: use standard 'generic-y' model for <asm/hw_irq.h> tile: use asm-generic version of <asm/local64.h> tile PCI RC: add comment about "PCI hole" problem tile: remove DEBUG_EXTRA_FLAGS kernel config option tile: add virt_to_kpte() API and clean up and document behavior tile: support FRAME_POINTER tile: support reporting Tilera hypervisor statistics ...
2013-09-06tile: rework <asm/cmpxchg.h>Chris Metcalf
The macrology in cmpxchg.h was designed to allow arbitrary pointer and integer values to be passed through the routines. To support cmpxchg() on 64-bit values on the 32-bit tilepro architecture, we used the idiom "(typeof(val))(typeof(val-val))". This way, in the "size 8" branch of the switch, when the underlying cmpxchg routine returns a 64-bit quantity, we cast it first to a typeof(val-val) quantity (i.e. size_t if "val" is a pointer) with no warnings about casting between pointers and integers of different sizes, then cast onwards to typeof(val), again with no warnings. If val is not a pointer type, the additional cast is a no-op. We can't replace the typeof(val-val) cast with (for example) unsigned long, since then if "val" is really a 64-bit type, we cast away the high bits. HOWEVER, this fails with current gcc (through 4.7 at least) if "val" is a pointer to an incomplete type. Unfortunately gcc isn't smart enough to realize that "val - val" will always be a size_t type even if it's an incomplete type pointer. Accordingly, I've reworked the way we handle the casting. We have given up the ability to use cmpxchg() on 64-bit values on tilepro, which is OK in the kernel since we should use cmpxchg64() explicitly on such values anyway. As a result, I can just use simple "unsigned long" casts internally. As I reworked it, I realized it would be cleaner to move the architecture-specific conditionals for cmpxchg and xchg out of the atomic.h headers and into cmpxchg, and then use the cmpxchg() and xchg() primitives directly in atomic.h and elsewhere. This allowed the cmpxchg.h header to stand on its own without relying on the implicit include of it that is performed by <asm/atomic.h>. It also allowed collapsing the atomic_xchg/atomic_cmpxchg routines from atomic_{32,64}.h into atomic.h. I improved the tests that guard the allowed size of the arguments to the routines to use a __compiletime_error() test. (By avoiding the use of BUILD_BUG, I could include cmpxchg.h into bitops.h as well and use the macros there, which is otherwise impossible due to include order dependency issues.) The tilepro _atomic_xxx internal methods were previously set up to take atomic_t and atomic64_t arguments, which isn't as convenient with the new model, so I modified them to take int or u64 arguments, which is consistent with how they used the arguments internally anyway, so provided some nice simplification there too. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile PCI RC: make default consistent DMA mask 32-bitChris Metcalf
This change sets the PCI devices' initial DMA capabilities conservatively and promotes them at the request of the driver, as opposed to assuming advanced DMA capabilities. The old design runs the risk of breaking drivers that assume default capabilities. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: make __write_once a synonym for __read_mostlyChris Metcalf
This was really only useful for TILE64 when we mapped the kernel data with small pages. Now we use a huge page and we really don't want to map different parts of the kernel data in different ways. We retain the __write_once name in case we want to bring it back to life at some point in the future. Note that this change uncovered a latent bug where the "smp_topology" variable happened to always be aligned mod 8 so we could store two "int" values at once, but when we eliminated __write_once it ended up only aligned mod 4. Fix with an explicit annotation. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: remove support for TILE64Chris Metcalf
This chip is no longer being actively developed for (it was superceded by the TILEPro64 in 2008), and in any case the existing compiler and toolchain in the community do not support it. It's unlikely that the kernel works with TILE64 at this point as the configuration has not been tested in years. The support is also awkward as it requires maintaining a significant number of ifdefs. So, just remove it altogether. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: use asm-generic/bitops/builtin-*.hAkinobu Mita
The definisions of __ffs(), __fls(), and ffs() for tile are almost same as asm-generic/bitops-*.h. The only difference is that it is defined as __always_inline or inline. So this switches to use those headers. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [moved #includes to end]
2013-09-03tile: use standard 'generic-y' model for <asm/hw_irq.h>Chris Metcalf
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: use asm-generic version of <asm/local64.h>Chris Metcalf
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile PCI RC: add comment about "PCI hole" problemChris Metcalf
Explain the rationale of not overlapping the 64-bit DMA window with the PA range. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: add virt_to_kpte() API and clean up and document behaviorChris Metcalf
We use virt_to_pte(NULL, va) a lot, which isn't very obvious. I added virt_to_kpte(va) as a more obvious wrapper function, that also validates the va as being a kernel adddress. And, I fixed the semantics of virt_to_pte() so that we handle the pud and pmd the same way, and we now document the fact that we handle the final pte level differently. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tilegx: support KGDBChris Metcalf
Enter kernel debugger at boot with: --hvd UART_1=1 --hvx kgdbwait --hvx kgdboc=ttyS1,115200 or at runtime with: echo ttyS1,115200 > /sys/module/kgdboc/parameters/kgdboc echo g > /proc/sysrq-trigger Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: parameterize VA and PA space more cleanlyChris Metcalf
The existing code relied on the hardware definition (<arch/chip.h>) to specify how much VA and PA space was available. It's convenient to allow customizing this for some configurations, so provide symbols MAX_PA_WIDTH and MAX_VA_WIDTH in <asm/page.h> that can be modified if desired. Additionally, move away from the MEM_XX_INTRPT nomenclature to define the start of various regions within the VA space. In fact the cleaner symbol is, for example, MEM_SV_START, to indicate the start of the area used for supervisor code; the actual address of the interrupt vectors is not as important, and can be changed if desired. As part of this change, convert from "intrpt1" nomenclature (which built in the old privilege-level 1 model) to a simple "intrpt". Also strip out some tilepro-specific code supporting modifying the PL the kernel could run at, since we don't actually support using different PLs in tilepro, only tilegx. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: don't assume user privilege is zeroChris Metcalf
Technically, user privilege is anything less than kernel privilege. We modify the existing user_mode() macro to have this semantic (and use it in a couple of places it wasn't being used before), and add an IS_KERNEL_EX1() macro to the assembly code as well. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: handle super huge pages in virt_to_pteChris Metcalf
This tile-specific API had a minor bug, in that if a super huge (>4GB) page mapped a particular address range, we wouldn't handle it correctly. As part of fixing that bug, I also cleaned up some of the pud and pmd accessors to make them more consistent. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tilegx: change how we find the kernel stackChris Metcalf
Previously, we used a special-purpose register (SPR_SYSTEM_SAVE_K_0) to hold the CPU number and the top of the current kernel stack by using the low bits to hold the CPU number, and using the high bits to hold the address of the page just above where we'd want the kernel stack to be. That way we could initialize a new SP when first entering the kernel by just masking the SPR value and subtracting a couple of words. However, it's actually more useful to be able to place an arbitrary kernel-top value in the SPR. This allows us to create a new stack context (e.g. for virtualization) with an arbitrary top-of-stack VA. To make this work, we now store the CPU number in the high bits, above the highest legal VA bit (42 bits in the current tilegx microarchitecture). The full 42 bits are thus available to store the top of stack value. Getting the current cpu (a relatively common operation) is still fast; it's now a shift rather than a mask. We make this change only for tilegx, since tilepro has too few SPR bits to do this, and we don't need this support on tilepro anyway. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: fix some -Wsign-compare warningsChris Metcalf
Normally the build doesn't include these warnings, but at one point I built with -Wsign-compare, and noticed a few things that are technically bugs. This change fixes those things. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: remove set/clear_fixmap APIsChris Metcalf
Nothing in the codebase was using them, and as written they took "unsigned long" as the physical address rather than "phys_addr_t", which is wrong on tilepro anyway. Rather than fixing stale APIs, just remove them; if there's ever demand for them on this platform, we can put them back. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: support ASLR fullyTony Lu
With this change, tile Linux now supports address-space layout randomization for shared objects, stack, heap and vdso. Acked-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Tony Lu <zlu@tilera.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: use proper .align directives on __ex_table sectionsChris Metcalf
This may fix a reported bug where an R_TILEGX_64 in a module was not pointing to an aligned address. Reported-by: Simon Marchi <simon.marchi@polymtl.ca> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: support kprobes on tilegxTony Lu
This change includes support for Kprobes, Jprobes and Return Probes. Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Tony Lu <zlu@tilera.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: support ftrace on tilegxTony Lu
This commit adds support for static ftrace, graph function support, and dynamic tracer support. Signed-off-by: Tony Lu <zlu@tilera.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: implement gettimeofday() via vDSOChris Metcalf
This change creates the framework for vDSO calls, makes the existing rt_sigreturn() mechanism use it, and adds a fast gettimeofday(). Now that we need to expose the vDSO address to userspace, we add AT_SYSINFO_EHDR to the set of aux entries provided to userspace. (You can disable any extra vDSO support by booting with vdso=0, but the rt_sigreturn vDSO page will still be provided.) Note that glibc has supported the tile vDSO since release 2.17. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: improve big-endian supportChris Metcalf
First, fix a bug in asm/unaligned.h; we need to just use the asm-generic unaligned.h so we properly choose endian-correct flavors. Second, keep the hv/hypervisor.h ABI fully "native" in the sense that we don't have __BIG_ENDIAN__ ifdefs there. Instead, we use macros in the head_NN.S assembly code to properly extract two 32-bit structure members from a 64-bit register holding the structure. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: support CONFIG_PREEMPTChris Metcalf
This change adds support for CONFIG_PREEMPT (full kernel preemption). In addition to the core support, this change includes a number of places where we fix up uses of smp_processor_id() and per-cpu variables. I also eliminate the PAGE_HOME_HERE and PAGE_HOME_UNKNOWN values for page homing, as it turns out they weren't being used. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: avoid recursive backtrace faultsChris Metcalf
This change adds support for avoiding recursive backtracer crashes; we haven't seen this in practice other than when things are seriously corrupt, but it may help avoid losing the root cause of a crash. Also, don't abort kernel backtracers for invalid userspace PC's. If we do, we lose the ability to backtrace through a userspace call to a bad address above PAGE_OFFSET, even though that it can be perfectly reasonable to continue the backtrace in such a case. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: fast-path unaligned memory access for tilegxChris Metcalf
This change enables unaligned userspace memory access via a kernel fast path on tilegx. The kernel tracks user PC/instruction pairs per-thread using a direct-mapped cache in userspace. The cache maps those PC/instruction pairs to JIT'ed instruction sequences that load or store using byte-wide load store intructions and then synthesize 2-, 4- or 8-byte load or store results. Once an instruction has been seen to generate an unaligned access once, subsequent hits on that instruction typically require overhead of only around 50 cycles if cache and TLB is hot. We support the prctl() PR_GET_UNALIGN / PR_SET_UNALIGN sys call to enable or disable unaligned fixups on a per-process basis. To do this we pull some of the tilepro unaligned support out of the single_step.c file; tilepro uses instruction disassembly for both single-step and unaligned access support. Since tilegx actually has hardware singlestep support, though, it's cleaner to keep the tilegx unaligned access code in a separate file. While we're at it, properly rename the tilepro-specific types, etc., to have tilepro suffixes instead of generic tile suffixes. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-12tile: various console improvementsChris Metcalf
This change improves and cleans up the tile console. - We enable HVC_IRQ support on tilegx, with the addition of a new Tilera hypervisor API for tilegx to allow a console IPI. If IPI support is not available we fall back to the previous polling mode. - We simplify the earlyprintk code to use CON_BOOT and eliminate some of the other supporting earlyprintk code. - A new tile_console_write() primitive is used to send output to the console and is factored out of the hvc_tile driver. This lets us support a "sim_console" boot argument to allow using simulator hooks to send output to the "console" as a slightly faster alternative to emulating the hardware more directly. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-06tile PCI RC: remove stale include of linux/numa.hChris Metcalf
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-06tile PCI RC: add dma_get_required_mask()Chris Metcalf
The standard kernel function dma_get_required_mask() uses the highest DRAM address to determine if 32-bit or 64-bit DMA addressing is needed. This only works on architectures that have direct mapping between the PA and the PCI address space, i.e. those that don't have I/O TLBs or have I/O TLB but choose to use direct mapping. Neither of these are true for tilegx. Whether to use 64-bit DMA should depend on the PCI device's capability only, not on the amount of DRAM installeds, so we now advertise a 64-bit DMA mask unconditionally. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-06tile PCI RC: eliminate pci_controller.mem_resources fieldChris Metcalf
The .mem_resources[] field in the pci_controller struct is now obsoleted by the .mem_space and .io_space fields. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-06tile PCI RC: restructure TRIO initializationChris Metcalf
The TRIO shim initialization is shared with other kernel drivers such as the endpoint and StreamIO drivers, so reorganize the initialization flow to ensure that the root complex driver properly initializes TRIO state regardless of what kind of TRIO driver will end up using the shim. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-06tile PCI RC: support I/O space accessChris Metcalf
To enable this functionality, configure CONFIG_TILE_PCI_IO. Without this flag, the kernel still assigns I/O address ranges to the devices, but no TRIO resource and mapping support is provided. We assign disjoint I/O address ranges to separate PCIe domains. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-06tile: support LSI MEGARAID SAS HBA hybrid dma_opsChris Metcalf
The LSI MEGARAID SAS HBA suffers from the problem where it can do 64-bit DMA to streaming buffers but not to consistent buffers. In other words, 64-bit DMA is used for disk data transfers and 32-bit DMA must be used for control message transfers. According to LSI, the firmware is not fully functional yet. This change implements a kind of hybrid dma_ops to support this. Note that on most other platforms, the 64-bit DMA addressing space is the same as the 32-bit DMA space and they overlap the physical memory space. No special arrangement is needed to support this kind of mixed DMA capability. On TILE-Gx, the 64-bit DMA space is completely separate from the 32-bit DMA space. Due to the use of the IOMMU, the 64-bit DMA space doesn't overlap the physical memory space. On the other hand, the 32-bit DMA space overlaps the physical memory space under 4GB. The separate address spaces make it necessary to have separate dma_ops. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-05tile PCI RC: cleanups for tilepro PCI RCChris Metcalf
- remove unneeded <linux/bootmem.h> include in pci.c - eliminate unused pci_controller.first_busno field - prefer msleep to mdelay - remove stale comment about pci_scan_bus_parented() Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-02tile: optimize strnlen using SIMD instructionsKen Steele
Using strlen as a model, add length checking to create strnlen. Signed-off-by: Ken Steele <ken@tilera.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-07-31tile: convert uses of "inv" to "finv"Chris Metcalf
The "inv" (invalidate) instruction is generally less safe than "finv" (flush and invalidate), as it will drop dirty data from the cache. It turns out we have almost no need for "inv" (other than for the older 32-bit architecture in some limited cases), so convert to "finv" where possible and delete the extra "inv" infrastructure. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-07-29tile / cpu topology: remove stale Macro arch_provides_topology_pointersHanjun Guo
Macro arch_provides_topology_pointers is pointless now, remove it. Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-17arch: tile: include: asm: add cmpxchg64() definitionChen Gang
Need add cmpxchg64(), or will cause compiling issue. Need define it as cmpxchg() only for 64-bit operation, since cmpxchg() can support 8 bytes. The related error (with allmodconfig): drivers/block/blockconsole.c: In function ‘bcon_advance_console_bytes’: drivers/block/blockconsole.c:164:2: error: implicit declaration of function ‘cmpxchg64’ [-Werror=implicit-function-declaration] Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-07-03tile: normalize global variables exported by vmlinux.ldsJiang Liu
Normalize global variables exported by vmlinux.lds to conform usage guidelines from include/asm-generic/sections.h. 1) Use _text to mark the start of the kernel image including the head text, and _stext to mark the start of the .text section. 2) Export mandatory global variables __init_begin and __init_end. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-02Merge branch 'sched-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull voluntary preemption fixes from Ingo Molnar: "This tree contains a speedup which is achieved through better might_sleep()/might_fault() preemption point annotations for uaccess functions, by Michael S Tsirkin: 1. The only reason uaccess routines might sleep is if they fault. Make this explicit for all architectures. 2. A voluntary preemption point in uaccess functions means compiler can't inline them efficiently, this breaks assumptions that they are very fast and small that e.g. net code seems to make. Remove this preemption point so behaviour matches with what callers assume. 3. Accesses (e.g through socket ops) to kernel memory with KERNEL_DS like net/sunrpc does will never sleep. Remove an unconditinal might_sleep() in the might_fault() inline in kernel.h (used when PROVE_LOCKING is not set). 4. Accesses with pagefault_disable() return EFAULT but won't cause caller to sleep. Check for that and thus avoid might_sleep() when PROVE_LOCKING is set. These changes offer a nice speedup for CONFIG_PREEMPT_VOLUNTARY=y kernels, here's a network bandwidth measurement between a virtual machine and the host: before: incoming: 7122.77 Mb/s outgoing: 8480.37 Mb/s after: incoming: 8619.24 Mb/s [ +21.0% ] outgoing: 9455.42 Mb/s [ +11.5% ] I kept these changes in a separate tree, separate from scheduler changes, because it's a mixed MM and scheduler topic" * 'sched-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: mm, sched: Allow uaccess in atomic with pagefault_disable() mm, sched: Drop voluntary schedule from might_fault() x86: uaccess s/might_sleep/might_fault/ tile: uaccess s/might_sleep/might_fault/ powerpc: uaccess s/might_sleep/might_fault/ mn10300: uaccess s/might_sleep/might_fault/ microblaze: uaccess s/might_sleep/might_fault/ m32r: uaccess s/might_sleep/might_fault/ frv: uaccess s/might_sleep/might_fault/ arm64: uaccess s/might_sleep/might_fault/ asm-generic: uaccess s/might_sleep/might_fault/
2013-07-02Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes: - load-calculation cleanups and improvements, by Alex Shi - various nohz related tidying up of statisics, by Frederic Weisbecker - factor out /proc functions to kernel/sched/proc.c, by Paul Gortmaker - simplify the RT policy scheduler, by Kirill Tkhai - various fixes and cleanups" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits) sched/debug: Remove CONFIG_FAIR_GROUP_SCHED mask sched/debug: Fix formatting of /proc/<PID>/sched sched: Fix typo in struct sched_avg member description sched/fair: Fix typo describing flags in enqueue_entity sched/debug: Add load-tracking statistics to task sched: Change get_rq_runnable_load() to static and inline sched/tg: Remove tg.load_weight sched/cfs_rq: Change atomic64_t removed_load to atomic_long_t sched/tg: Use 'unsigned long' for load variable in task group sched: Change cfs_rq load avg to unsigned long sched: Consider runnable load average in move_tasks() sched: Compute runnable load avg in cpu_load and cpu_avg_load_per_task sched: Update cpu load after task_tick sched: Fix sleep time double accounting in enqueue entity sched: Set an initial value of runnable avg for new forked task sched: Move a few runnable tg variables into CONFIG_SMP Revert "sched: Introduce temporary FAIR_GROUP_SCHED dependency for load-tracking" sched: Don't mix use of typedef ctl_table and struct ctl_table sched: Remove WARN_ON(!sd) from init_sched_groups_power() sched: Fix memory leakage in build_sched_groups() ...
2013-06-29consolidate io_remap_pfn_range definitionsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-19sched: Rename sched.c as sched/core.c in comments and DocumentationViresh Kumar
Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time back and the comments/Documentation never got updated. I figured it out when I was going through sched-domains.txt and so thought of fixing it globally. I haven't crossed check if the stuff that is referenced in sched/core.c by all these files is still present and hasn't changed as that wasn't the motive behind this patch. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-28tile: uaccess s/might_sleep/might_fault/Michael S. Tsirkin
The only reason uaccess routines might sleep is if they fault. Make this explicit. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1369577426-26721-8-git-send-email-mst@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds
Pull tile arch changes from Chris Metcalf: "These are some minor new feature work and other changes that didn't merit getting pushed up after the 3.9 merge window closed. There should be a lot more activity in the 3.11 merge window" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: arch/tile: Fix syscall return value passed to tracepoint tile: comment assumption about __insn_mtspr for <asm/irqflags.h> tile: ns2cycles should use __raw_get_cpu_var arch: remove KCORE_ELF again [tile] tile: remove two outdated Kconfig entries tile: support atomic64_dec_if_positive() tile: support TIF_SYSCALL_TRACEPOINT; select HAVE_SYSCALL_TRACEPOINTS tile: Add definition of NR_syscalls tile: move declaration of sys_call_table to <asm/syscall.h> arch/tile: Enable HAVE_ARCH_TRACEHOOK arch/tile: Call tracehook_report_syscall_{entry,exit} in syscall trace
2013-05-01Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKSStephen Boyd
The help text for this config is duplicated across the x86, parisc, and s390 Kconfig.debug files. Arnd Bergman noted that the help text was slightly misleading and should be fixed to state that enabling this option isn't a problem when using pre 4.4 gcc. To simplify the rewording, consolidate the text into lib/Kconfig.debug and modify it there to be more explicit about when you should say N to this config. Also, make the text a bit more generic by stating that this option enables compile time checks so we can cover architectures which emit warnings vs. ones which emit errors. The details of how an architecture decided to implement the checks isn't as important as the concept of compile time checking of copy_from_user() calls. While we're doing this, remove all the copy_from_user_overflow() code that's duplicated many times and place it into lib/ so that any architecture supporting this option can get the function for free. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Helge Deller <deller@gmx.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>