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2013-09-13tile: remove HUGE_VMAP dead codeChris Metcalf1-2/+0
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>
2013-09-12arch: mm: pass userspace fault flag to generic fault handlerJohannes Weiner1-2/+5
Unlike global OOM handling, memory cgroup code will invoke the OOM killer in any OOM situation because it has no way of telling faults occuring in kernel context - which could be handled more gracefully - from user-triggered faults. Pass a flag that identifies faults originating in user space from the architecture-specific fault handlers to generic code so that memcg OOM handling can be improved. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12arch: mm: remove obsolete init OOM protectionJohannes Weiner1-6/+0
The memcg code can trap tasks in the context of the failing allocation until an OOM situation is resolved. They can hold all kinds of locks (fs, mm) at this point, which makes it prone to deadlocking. This series converts memcg OOM handling into a two step process that is started in the charge context, but any waiting is done after the fault stack is fully unwound. Patches 1-4 prepare architecture handlers to support the new memcg requirements, but in doing so they also remove old cruft and unify out-of-memory behavior across architectures. Patch 5 disables the memcg OOM handling for syscalls, readahead, kernel faults, because they can gracefully unwind the stack with -ENOMEM. OOM handling is restricted to user triggered faults that have no other option. Patch 6 reworks memcg's hierarchical OOM locking to make it a little more obvious wth is going on in there: reduce locked regions, rename locking functions, reorder and document. Patch 7 implements the two-part OOM handling such that tasks are never trapped with the full charge stack in an OOM situation. This patch: Back before smart OOM killing, when faulting tasks were killed directly on allocation failures, the arch-specific fault handlers needed special protection for the init process. Now that all fault handlers call into the generic OOM killer (see commit 609838cfed97: "mm: invoke oom-killer from remaining unconverted page fault handlers"), which already provides init protection, the arch-specific leftovers can be removed. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-03tile: remove support for TILE64Chris Metcalf1-53/+17
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: don't assume user privilege is zeroChris Metcalf1-2/+2
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: support kprobes on tilegxTony Lu1-0/+12
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>
2013-08-13tile: remove calls to arch_flush_lazy_mmu_mode()Chris Metcalf1-3/+2
Since it's a no-op on tile anyway, there's no reason to be calling it in tile-specific code. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: fast-path unaligned memory access for tilegxChris Metcalf1-0/+41
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: fix tilegx vmalloc_sync_all BUG_ONChris Metcalf1-1/+2
As specified, the test wasn't correct, and in any case it should be a BUILD_BUG_ON. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-07-09mm: invoke oom-killer from remaining unconverted page fault handlersJohannes Weiner1-4/+4
A few remaining architectures directly kill the page faulting task in an out of memory situation. This is usually not a good idea since that task might not even use a significant amount of memory and so may not be the optimal victim to resolve the situation. Since 2.6.29's 1c0fe6e ("mm: invoke oom-killer from page fault") there is a hook that architecture page fault handlers are supposed to call to invoke the OOM killer and let it pick the right task to kill. Convert the remaining architectures over to this hook. To have the previous behavior of simply taking out the faulting task the vm.oom_kill_allocating_task sysctl can be set to 1. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Cc: James Hogan <james.hogan@imgtec.com> Cc: David Howells <dhowells@redhat.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-23arch/tile: eliminate pt_regs trampolines for syscallsChris Metcalf1-2/+3
Using the new current_pt_regs() model, we can remove some trampolines from assembly code and call directly to the C syscall implementations. rt_sigreturn() and clone() still need some assembly wrapping, but no longer are passed a pt_regs pointer. sigaltstack() and the tilepro-specific cmpxchg_badaddr() syscalls are now just straight C. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-10-09readahead: fault retry breaks mmap file read random detectionShaohua Li1-0/+1
.fault now can retry. The retry can break state machine of .fault. In filemap_fault, if page is miss, ra->mmap_miss is increased. In the second try, since the page is in page cache now, ra->mmap_miss is decreased. And these are done in one fault, so we can't detect random mmap file access. Add a new flag to indicate .fault is tried once. In the second try, skip ra->mmap_miss decreasing. The filemap_fault state machine is ok with it. I only tested x86, didn't test other archs, but looks the change for other archs is obvious, but who knows :) Signed-off-by: Shaohua Li <shaohua.li@fusionio.com> Cc: Rik van Riel <riel@redhat.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-25tile/mm/fault.c: Port OOM changes to handle_page_faultKautuk Consul1-5/+27
Commit d065bd810b6deb67d4897a14bfe21f8eb526ba99 (mm: retry page fault when blocking on disk transfer) and commit 37b23e0525d393d48a7d59f870b3bc061a30ccdb (x86,mm: make pagefault killable) The above commits introduced changes into the x86 pagefault handler for making the page fault handler retryable as well as killable. These changes reduce the mmap_sem hold time, which is crucial during OOM killer invocation. Port these changes to tile. Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com> [cmetcalf@tilera.com: initialize "flags" after "write" updated.] Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-05-25arch/tile: support multiple huge page sizes dynamicallyChris Metcalf1-1/+1
This change adds support for a new "super" bit in the PTE, using the new arch_make_huge_pte() method. The Tilera hypervisor sees the bit set at a given level of the page table and gangs together 4, 16, or 64 consecutive pages from that level of the hierarchy to create a larger TLB entry. One extra "super" page size can be specified at each of the three levels of the page table hierarchy on tilegx, using the "hugepagesz" argument on the boot command line. A new hypervisor API is added to allow Linux to tell the hypervisor how many PTEs to gang together at each level of the page table. To allow pre-allocating huge pages larger than the buddy allocator can handle, this change modifies the Tilera bootmem support to put all of memory on tilegx platforms into bootmem. As part of this change I eliminate the vestigial CONFIG_HIGHPTE support, which never worked anyway, and eliminate the hv_page_size() API in favor of the standard vma_kernel_pagesize() API. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-02arch/tile: don't enable irqs unconditionally in page fault handlerChris Metcalf1-2/+5
If we took a page fault while we had interrupts disabled, we shouldn't enable them in the page fault handler. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-02arch/tile: don't wait for migrating PTEs in an NMI handlerChris Metcalf1-3/+10
Doing so raises the possibility of self-deadlock if we are waiting for a backtrace for an oprofile or perf interrupt while we are in the middle of migrating our own stack page. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-02arch/tile: fix a couple of comments that needed updatingChris Metcalf1-1/+1
Not associated with any code changes, so I'm just lumping these comment changes into a commit by themselves. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-03-28Disintegrate asm/system.h for TileDavid Howells1-1/+0
Disintegrate asm/system.h for Tile. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com>
2011-12-11tile: Make tile use the new is_idle_task() APIPaul E. McKenney1-2/+2
Change from direct comparison of ->pid with zero to is_idle_task(). Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com>
2011-05-19arch/tile: support signal "exception-trace" hookChris Metcalf1-9/+15
This change adds support for /proc/sys/debug/exception-trace to tile. Like x86 and sparc, by default it is set to "1", generating a one-line printk whenever a user process crashes. By setting it to "2", we get a much more complete userspace diagnostic at crash time, including a user-space backtrace, register dump, and memory dump around the address of the crash. Some vestiges of the Tilera-internal version of this support are removed with this patch (the show_crashinfo variable and the arch_coredump_signal function). We retain a "crashinfo" boot parameter which allows you to set the boot-time value of exception-trace. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-05-02arch/tile: support TIF_NOTIFY_RESUMEChris Metcalf1-2/+4
This support is required for CONFIG_KEYS, NFSv4 kernel DNS, etc. The change is slightly more complex than the minimal thing, since I took advantage of having to go into the assembly code to just move a bunch of stuff into C code: specifically, the schedule(), do_async_page_fault(), do_signal(), and single_step_once() support, in addition to the TIF_NOTIFY_RESUME support. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-03-31Fix common misspellingsLucas De Marchi1-1/+1
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-10arch/tile: fix some comments and whitespaceChris Metcalf1-8/+0
This is a grab bag of changes with no actual change to generated code. This includes whitespace and comment typos, plus a couple of stale comments being removed. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-11-17BKL: remove extraneous #include <smp_lock.h>Arnd Bergmann1-1/+0
The big kernel lock has been removed from all these files at some point, leaving only the #include. Remove this too as a cleanup. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-15arch/tile: parameterize system PLs to support KVM portChris Metcalf1-3/+3
While not a port to KVM (yet), this change modifies the kernel to be able to build either at PL1 or at PL2 with a suitable config switch. Pushing up this change avoids handling branch merge issues going forward with the KVM work. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-10-14arch/tile: Use <asm-generic/syscalls.h>Chris Metcalf1-3/+3
With this change we now include <asm-generic/syscalls.h> into the "tile" version of the header. To take full advantage of the prototypes there, we also change our naming convention for "struct pt_regs *" syscalls so that, e.g., _sys_execve() is the "true" syscall entry, which sets the appropriate register to point to the pt_regs before calling sys_execve(). While doing this I realized I no longer needed the fork and vfork entry point stubs, since those functions aren't in the generic syscall ABI, so I removed them as well. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-08-13arch/tile: Various cleanups.Chris Metcalf1-0/+8
This change rolls up random cleanups not representing any actual bugs. - Remove a stale CONFIG_ value from the default tile_defconfig - Remove unused tns_atomic_xxx() family of methods from <asm/atomic.h> - Optimize get_order() using Tile's "clz" instruction - Fix a bad hypervisor upcall name (not currently used in Linux anyway) - Use __copy_in_user_inatomic() name for consistency, and export it - Export some additional hypervisor driver I/O upcalls and some homecache calls - Remove the obfuscating MEMCPY_TEST_WH64 support code - Other stray comment cleanups, #if 0 removal, etc. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-07-06arch/tile: Miscellaneous cleanup changes.Chris Metcalf1-51/+13
This commit is primarily changes caused by reviewing "sparse" and "checkpatch" output on our sources, so is somewhat noisy, since things like "printk() -> pr_err()" (or whatever) throughout the codebase tend to get tedious to read. Rather than trying to tease apart precisely which things changed due to which type of code review, this commit includes various cleanups in the code: - sparse: Add declarations in headers for globals. - sparse: Fix __user annotations. - sparse: Using gfp_t consistently instead of int. - sparse: removing functions not actually used. - checkpatch: Clean up printk() warnings by using pr_info(), etc.; also avoid partial-line printks except in bootup code. - checkpatch: Use exposed structs rather than typedefs. - checkpatch: Change some C99 comments to C89 comments. In addition, a couple of minor other changes are rolled in to this commit: - Add support for a "raise" instruction to cause SIGFPE, etc., to be raised. - Remove some compat code that is unnecessary when we fully eliminate some of the deprecated syscalls from the generic syscall ABI. - Update the tile_defconfig to reflect current config contents. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2010-06-04arch/tile: core support for Tilera 32-bit chips.Chris Metcalf1-0/+905
This change is the core kernel support for TILEPro and TILE64 chips. No driver support (except the console driver) is included yet. This includes the relevant Linux headers in asm/; the low-level low-level "Tile architecture" headers in arch/, which are shared with the hypervisor, etc., and are build-system agnostic; and the relevant hypervisor headers in hv/. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Reviewed-by: Paul Mundt <lethal@linux-sh.org>