aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/process.c
AgeCommit message (Collapse)Author
2013-12-02Merge branch 'linux-linaro-lsk' into linux-linaro-lsk-androidMark Brown
2013-11-29sched, idle: Fix the idle polling state logicPeter Zijlstra
commit ea8117478918a4734586d35ff530721b682425be upstream. Mike reported that commit 7d1a9417 ("x86: Use generic idle loop") regressed several workloads and caused excessive reschedule interrupts. The patch in question failed to notice that the x86 code had an inverted sense of the polling state versus the new generic code (x86: default polling, generic: default !polling). Fix the two prominent x86 mwait based idle drivers and introduce a few new generic polling helpers (fixing the wrong smp_mb__after_clear_bit usage). Also switch the idle routines to using tif_need_resched() which is an immediate TIF_NEED_RESCHED test as opposed to need_resched which will end up being slightly different. Reported-by: Mike Galbraith <bitbucket@online.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: lenb@kernel.org Cc: tglx@linutronix.de Link: http://lkml.kernel.org/n/tip-nc03imb0etuefmzybzj7sprf@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-01Move x86_64 idle notifiers to genericTodd Poynor
Move the x86_64 idle notifiers originally by Andi Kleen and Venkatesh Pallipadi to generic. Change-Id: Idf29cda15be151f494ff245933c12462643388d5 Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Todd Poynor <toddpoynor@google.com>
2013-06-11idle: Add the stack canary init to cpu_startup_entry()Thomas Gleixner
Moving x86 to the generic idle implementation (commit 7d1a9417 "x86: Use generic idle loop") wreckaged the stack protector. I stupidly missed that boot_init_stack_canary() must be inlined from a function which never returns, but I put that call into arch_cpu_idle_prepare() which of course returns. I pondered to play tricks with arch_cpu_idle_prepare() first, but then I noticed, that the other archs which have implemented the stackprotector (ARM and SH) do not initialize the canary for the non-boot cpus. So I decided to move the boot_init_stack_canary() call into cpu_startup_entry() ifdeffed with an CONFIG_X86 for now. This #ifdef is just a temporary measure as I don't want to inflict the boot_init_stack_canary() call on ARM and SH that late in the cycle. I'll queue a patch for 3.11 which removes the #ifdef if the ARM/SH maintainers have no objection. Reported-by: Wouter van Kesteren <woutershep@gmail.com> Cc: x86@kernel.org Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-07x86: Fix idle consolidation falloutThomas Gleixner
The core code expects the arch idle code to return with interrupts enabled. The conversion missed two x86 cases which fail to do that. Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de> Tested-by: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305021557030.3972@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-30dump_stack: unify debug information printed by show_regs()Tejun Heo
show_regs() is inherently arch-dependent but it does make sense to print generic debug information and some archs already do albeit in slightly different forms. This patch introduces a generic function to print debug information from show_regs() so that different archs print out the same information and it's much easier to modify what's printed. show_regs_print_info() prints out the same debug info as dump_stack() does plus task and thread_info pointers. * Archs which didn't print debug info now do. alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r, metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc, um, xtensa * Already prints debug info. Replaced with show_regs_print_info(). The printed information is superset of what used to be there. arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86 * s390 is special in that it used to print arch-specific information along with generic debug info. Heiko and Martin think that the arch-specific extra isn't worth keeping s390 specfic implementation. Converted to use the generic version. Note that now all archs print the debug info before actual register dumps. An example BUG() dump follows. kernel BUG at /work/os/work/kernel/workqueue.c:4841! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000 RIP: 0010:[<ffffffff8234a07e>] [<ffffffff8234a07e>] init_workqueues+0x4/0x6 RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246 RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001 RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650 0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760 Call Trace: [<ffffffff81000312>] do_one_initcall+0x122/0x170 [<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8 [<ffffffff81c47760>] ? rest_init+0x140/0x140 [<ffffffff81c4776e>] kernel_init+0xe/0xf0 [<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0 [<ffffffff81c47760>] ? rest_init+0x140/0x140 ... v2: Typo fix in x86-32. v3: CPU number dropped from show_regs_print_info() as dump_stack_print_info() has been updated to print it. s390 specific implementation dropped as requested by s390 maintainers. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [tile bits] Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid changes from Ingo Molnar: "The biggest change is x86 CPU bug handling refactoring and cleanups, by Borislav Petkov" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, CPU, AMD: Drop useless label x86, AMD: Correct {rd,wr}msr_amd_safe warnings x86: Fold-in trivial check_config function x86, cpu: Convert AMD Erratum 400 x86, cpu: Convert AMD Erratum 383 x86, cpu: Convert Cyrix coma bug detection x86, cpu: Convert FDIV bug detection x86, cpu: Convert F00F bug detection x86, cpu: Expand cpufeature facility to include cpu bugs
2013-04-08x86: Use generic idle loopThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Magnus Damm <magnus.damm@gmail.com> Link: http://lkml.kernel.org/r/20130321215235.486594473@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org
2013-04-02x86, cpu: Convert AMD Erratum 400Borislav Petkov
Convert AMD erratum 400 to the bug infrastructure. Then, retract all exports for modules since they're not needed now and make the AMD erratum checking machinery local to amd.c. Use forward declarations to avoid shuffling too much code around needlessly. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1363788448-31325-7-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2013-02-18Merge branch 'release' of ↵Rafael J. Wysocki
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (35 commits) PM idle: remove global declaration of pm_idle unicore32 idle: delete stray pm_idle comment openrisc idle: delete pm_idle mn10300 idle: delete pm_idle microblaze idle: delete pm_idle m32r idle: delete pm_idle, and other dead idle code ia64 idle: delete pm_idle cris idle: delete idle and pm_idle ARM64 idle: delete pm_idle ARM idle: delete pm_idle blackfin idle: delete pm_idle sparc idle: rename pm_idle to sparc_idle sh idle: rename global pm_idle to static sh_idle x86 idle: rename global pm_idle to static x86_idle APM idle: register apm_cpu_idle via cpuidle tools/power turbostat: display SMI count by default intel_idle: export both C1 and C1E cpuidle: remove vestage definition of cpuidle_state_usage.driver_data x86 idle: remove 32-bit-only "no-hlt" parameter, hlt_works_ok flag x86 idle: remove mwait_idle() and "idle=mwait" cmdline param ... Conflicts: arch/x86/kernel/process.c (with PM / tracing commit 43720bd) drivers/acpi/processor_idle.c (with ACPICA commit 4f84291)
2013-02-18Merge branch 'misc' into releaseLen Brown
Conflicts: arch/x86/kernel/process.c Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-17x86 idle: rename global pm_idle to static x86_idleLen Brown
(pm_idle)() is being removed from linux/pm.h because Linux does not have such a cross-architecture concept. x86 uses an idle function pointer in its architecture specific code as a backup to cpuidle. So we re-name x86 use of pm_idle to x86_idle, and make it static to x86. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org
2013-02-17APM idle: register apm_cpu_idle via cpuidleLen Brown
Update APM to register its local idle routine with cpuidle. This allows us to stop exporting pm_idle to modules on x86. The Kconfig sub-option, APM_CPU_IDLE, now depends on on CPU_IDLE. Compile-tested only. Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Jiri Kosina <jkosina@suse.cz>
2013-02-10x86 idle: remove 32-bit-only "no-hlt" parameter, hlt_works_ok flagLen Brown
Remove 32-bit x86 a cmdline param "no-hlt", and the cpuinfo_x86.hlt_works_ok that it sets. If a user wants to avoid HLT, then "idle=poll" is much more useful, as it avoids invocation of HLT in idle, while "no-hlt" failed to do so. Indeed, hlt_works_ok was consulted in only 3 places. First, in /proc/cpuinfo where "hlt_bug yes" would be printed if and only if the user booted the system with "no-hlt" -- as there was no other code to set that flag. Second, check_hlt() would not invoke halt() if "no-hlt" were on the cmdline. Third, it was consulted in stop_this_cpu(), which is invoked by native_machine_halt()/reboot_interrupt()/smp_stop_nmi_callback() -- all cases where the machine is being shutdown/reset. The flag was not consulted in the more frequently invoked play_dead()/hlt_play_dead() used in processor offline and suspend. Since Linux-3.0 there has been a run-time notice upon "no-hlt" invocations indicating that it would be removed in 2012. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org
2013-02-10x86 idle: remove mwait_idle() and "idle=mwait" cmdline paramLen Brown
mwait_idle() is a C1-only idle loop intended to be more efficient than HLT, starting on Pentium-4 HT-enabled processors. But mwait_idle() has been replaced by the more general mwait_idle_with_hints(), which handles both C1 and deeper C-states. ACPI processor_idle and intel_idle use only mwait_idle_with_hints(), and no longer use mwait_idle(). Here we simplify the x86 native idle code by removing mwait_idle(), and the "idle=mwait" bootparam used to invoke it. Since Linux 3.0 there has been a boot-time warning when "idle=mwait" was invoked saying it would be removed in 2012. This removal was also noted in the (now removed:-) feature-removal-schedule.txt. After this change, kernels configured with (CONFIG_ACPI=n && CONFIG_INTEL_IDLE=n) when run on hardware that supports MWAIT will simply use HLT. If MWAIT is desired on those systems, cpuidle and the cpuidle drivers above can be enabled. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org
2013-02-10xen idle: make xen-specific macro xen-specificLen Brown
This macro is only invoked by Xen, so make its definition specific to Xen. > set_pm_idle_to_default() < xen_set_default_idle() Signed-off-by: Len Brown <len.brown@intel.com> Cc: xen-devel@lists.xensource.com
2013-01-26PM / tracing: remove deprecated power trace APIPaul Gortmaker
The text in Documentation said it would be removed in 2.6.41; the text in the Kconfig said removal in the 3.1 release. Either way you look at it, we are well past both, so push it off a cliff. Note that the POWER_CSTATE and the POWER_PSTATE are part of the legacy tracing API. Remove all tracepoints which use these flags. As can be seen from context, most already have a trace entry via trace_cpu_idle anyways. Also, the cpufreq/cpufreq.c PSTATE one is actually unpaired, as compared to the CSTATE ones which all have a clear start/stop. As part of this, the trace_power_frequency also becomes orphaned, so it too is deleted. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-12-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull big execve/kernel_thread/fork unification series from Al Viro: "All architectures are converted to new model. Quite a bit of that stuff is actually shared with architecture trees; in such cases it's literally shared branch pulled by both, not a cherry-pick. A lot of ugliness and black magic is gone (-3KLoC total in this one): - kernel_thread()/kernel_execve()/sys_execve() redesign. We don't do syscalls from kernel anymore for either kernel_thread() or kernel_execve(): kernel_thread() is essentially clone(2) with callback run before we return to userland, the callbacks either never return or do successful do_execve() before returning. kernel_execve() is a wrapper for do_execve() - it doesn't need to do transition to user mode anymore. As a result kernel_thread() and kernel_execve() are arch-independent now - they live in kernel/fork.c and fs/exec.c resp. sys_execve() is also in fs/exec.c and it's completely architecture-independent. - daemonize() is gone, along with its parts in fs/*.c - struct pt_regs * is no longer passed to do_fork/copy_process/ copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump. - sys_fork()/sys_vfork()/sys_clone() unified; some architectures still need wrappers (ones with callee-saved registers not saved in pt_regs on syscall entry), but the main part of those suckers is in kernel/fork.c now." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits) do_coredump(): get rid of pt_regs argument print_fatal_signal(): get rid of pt_regs argument ptrace_signal(): get rid of unused arguments get rid of ptrace_signal_deliver() arguments new helper: signal_pt_regs() unify default ptrace_signal_deliver flagday: kill pt_regs argument of do_fork() death to idle_regs() don't pass regs to copy_process() flagday: don't pass regs to copy_thread() bfin: switch to generic vfork, get rid of pointless wrappers xtensa: switch to generic clone() openrisc: switch to use of generic fork and clone unicore32: switch to generic clone(2) score: switch to generic fork/vfork/clone c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone() take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h mn10300: switch to generic fork/vfork/clone h8300: switch to generic fork/vfork/clone tile: switch to generic clone() ... Conflicts: arch/microblaze/include/asm/Kbuild
2012-11-28x86, um: switch to generic fork/vfork/cloneAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-26x86: Remove dead hlt_use_halt codeDaniel Lezcano
The hlt_use_halt function returns always true and there is only one definition of it. The default_idle function can then get ride of the if ... statement and we can remove the else branch. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linaro-dev@lists.linaro.org Cc: patches@linaro.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1351181591-8710-1-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-10-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull generic execve() changes from Al Viro: "This introduces the generic kernel_thread() and kernel_execve() functions, and switches x86, arm, alpha, um and s390 over to them." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits) s390: convert to generic kernel_execve() s390: switch to generic kernel_thread() s390: fold kernel_thread_helper() into ret_from_fork() s390: fold execve_tail() into start_thread(), convert to generic sys_execve() um: switch to generic kernel_thread() x86, um/x86: switch to generic sys_execve and kernel_execve x86: split ret_from_fork alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve() alpha: switch to generic kernel_thread() alpha: switch to generic sys_execve() arm: get rid of execve wrapper, switch to generic execve() implementation arm: optimized current_pt_regs() arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve() arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk] generic sys_execve() generic kernel_execve() new helper: current_pt_regs() preparation for generic kernel_thread() um: kill thread->forking um: let signal_delivered() do SIGTRAP on singlestepping into handler ...
2012-09-30x86, um/x86: switch to generic sys_execve and kernel_execveAl Viro
32bit wrapper is lost on that; 64bit one is *not*, since we need to arrange for full pt_regs on stack when we call sys_execve() and we need to load callee-saved ones from there afterwards. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30x86: split ret_from_forkAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-20x86: get rid of TIF_IRET hackeryAl Viro
TIF_NOTIFY_RESUME will work in precisely the same way; all that is achieved by TIF_IRET is appearing that there's some work to be done, so we end up on the iret exit path. Just use NOTIFY_RESUME. And for execve() do that in 32bit start_thread(), not sys_execve() itself. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-18x86, fpu: decouple non-lazy/eager fpu restore from xsaveSuresh Siddha
Decouple non-lazy/eager fpu restore policy from the existence of the xsave feature. Introduce a synthetic CPUID flag to represent the eagerfpu policy. "eagerfpu=on" boot paramter will enable the policy. Requested-by: H. Peter Anvin <hpa@zytor.com> Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1347300665-6209-2-git-send-email-suresh.b.siddha@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-09-18x86, fpu: use non-lazy fpu restore for processors supporting xsaveSuresh Siddha
Fundamental model of the current Linux kernel is to lazily init and restore FPU instead of restoring the task state during context switch. This changes that fundamental lazy model to the non-lazy model for the processors supporting xsave feature. Reasons driving this model change are: i. Newer processors support optimized state save/restore using xsaveopt and xrstor by tracking the INIT state and MODIFIED state during context-switch. This is faster than modifying the cr0.TS bit which has serializing semantics. ii. Newer glibc versions use SSE for some of the optimized copy/clear routines. With certain workloads (like boot, kernel-compilation etc), application completes its work with in the first 5 task switches, thus taking upto 5 #DNA traps with the kernel not getting a chance to apply the above mentioned pre-load heuristic. iii. Some xstate features (like AMD's LWP feature) don't honor the cr0.TS bit and thus will not work correctly in the presence of lazy restore. Non-lazy state restore is needed for enabling such features. Some data on a two socket SNB system: * Saved 20K DNA exceptions during boot on a two socket SNB system. * Saved 50K DNA exceptions during kernel-compilation workload. * Improved throughput of the AVX based checksumming function inside the kernel by ~15% as xsave/xrstor is faster than the serializing clts/stts pair. Also now kernel_fpu_begin/end() relies on the patched alternative instructions. So move check_fpu() which uses the kernel_fpu_begin/end() after alternative_instructions(). Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1345842782-24175-7-git-send-email-suresh.b.siddha@intel.com Merge 32-bit boot fix from, Link: http://lkml.kernel.org/r/1347300665-6209-4-git-send-email-suresh.b.siddha@intel.com Cc: Jim Kukunas <james.t.kukunas@linux.intel.com> Cc: NeilBrown <neilb@suse.de> Cc: Avi Kivity <avi@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-09-18x86, fpu: Unify signal handling code paths for x86 and x86_64 kernelsSuresh Siddha
Currently for x86 and x86_32 binaries, fpstate in the user sigframe is copied to/from the fpstate in the task struct. And in the case of signal delivery for x86_64 binaries, if the fpstate is live in the CPU registers, then the live state is copied directly to the user sigframe. Otherwise fpstate in the task struct is copied to the user sigframe. During restore, fpstate in the user sigframe is restored directly to the live CPU registers. Historically, different code paths led to different bugs. For example, x86_64 code path was not preemption safe till recently. Also there is lot of code duplication for support of new features like xsave etc. Unify signal handling code paths for x86 and x86_64 kernels. New strategy is as follows: Signal delivery: Both for 32/64-bit frames, align the core math frame area to 64bytes as needed by xsave (this where the main fpu/extended state gets copied to and excludes the legacy compatibility fsave header for the 32-bit [f]xsave frames). If the state is live, copy the register state directly to the user frame. If not live, copy the state in the thread struct to the user frame. And for 32-bit [f]xsave frames, construct the fsave header separately before the actual [f]xsave area. Signal return: As the 32-bit frames with [f]xstate has an additional 'fsave' header, copy everything back from the user sigframe to the fpstate in the task structure and reconstruct the fxstate from the 'fsave' header (Also user passed pointers may not be correctly aligned for any attempt to directly restore any partial state). At the next fpstate usage, everything will be restored to the live CPU registers. For all the 64-bit frames and the 32-bit fsave frame, restore the state from the user sigframe directly to the live CPU registers. 64-bit signals always restored the math frame directly, so we can expect the math frame pointer to be correctly aligned. For 32-bit fsave frames, there are no alignment requirements, so we can restore the state directly. "lat_sig catch" microbenchmark numbers (for x86, x86_64, x86_32 binaries) are with in the noise range with this change. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1343171129-2747-4-git-send-email-suresh.b.siddha@intel.com [ Merged in compilation fix ] Link: http://lkml.kernel.org/r/1344544736.8326.17.camel@sbsiddha-desk.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-06-06x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>Joe Perches
Use a more current logging style: - Bare printks should have a KERN_<LEVEL> for consistency's sake - Add pr_fmt where appropriate - Neaten some macro definitions - Convert some Ok output to OK - Use "%s: ", __func__ in pr_fmt for summit - Convert some printks to pr_<level> Message output is not identical in all cases. Signed-off-by: Joe Perches <joe@perches.com> Cc: levinsasha928@gmail.com Link: http://lkml.kernel.org/r/1337655007.24226.10.camel@joe2Laptop [ merged two similar patches, tidied up the changelog ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-23Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull fpu state cleanups from Ingo Molnar: "This tree streamlines further aspects of FPU handling by eliminating the prepare_to_copy() complication and moving that logic to arch_dup_task_struct(). It also fixes the FPU dumps in threaded core dumps, removes and old (and now invalid) assumption plus micro-optimizes the exit path by avoiding an FPU save for dead tasks." Fixed up trivial add-add conflict in arch/sh/kernel/process.c that came in because we now do the FPU handling in arch_dup_task_struct() rather than the legacy (and now gone) prepare_to_copy(). * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, fpu: drop the fpu state during thread exit x86, xsave: remove thread_has_fpu() bug check in __sanitize_i387_state() coredump: ensure the fpu state is flushed for proper multi-threaded core dump fork: move the real prepare_to_copy() users to arch_dup_task_struct()
2012-05-23Merge branches 'x86-asm-for-linus', 'x86-cleanups-for-linus', ↵Linus Torvalds
'x86-cpu-for-linus', 'x86-debug-for-linus' and 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull initial trivial x86 stuff from Ingo Molnar. Various random cleanups and trivial fixes. * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86-64: Eliminate dead ia32 syscall handlers * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/pci-calgary_64.c: Remove obsoleted simple_strtoul() usage x86: Don't continue booting if we can't load the specified initrd x86: kernel/dumpstack.c simple_strtoul cleanup x86: kernel/check.c simple_strtoul cleanup debug: Add CONFIG_READABLE_ASM x86: spinlock.h: Remove REG_PTR_MODE * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cache_info: Fix setup of l2/l3 ids * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Avoid double stack traces with show_regs() * 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, microcode: microcode_core.c simple_strtoul cleanup
2012-05-22Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "The biggest change is the cleanup/simplification of the load-balancer: instead of the current practice of architectures twiddling scheduler internal data structures and providing the scheduler domains in colorfully inconsistent ways, we now have generic scheduler code in kernel/sched/core.c:sched_init_numa() that looks at the architecture's node_distance() parameters and (while not fully trusting it) deducts a NUMA topology from it. This inevitably changes balancing behavior - hopefully for the better. There are various smaller optimizations, cleanups and fixlets as well" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Taint kernel with TAINT_WARN after sleep-in-atomic bug sched: Remove stale power aware scheduling remnants and dysfunctional knobs sched/debug: Fix printing large integers on 32-bit platforms sched/fair: Improve the ->group_imb logic sched/nohz: Fix rq->cpu_load[] calculations sched/numa: Don't scale the imbalance sched/fair: Revert sched-domain iteration breakage sched/x86: Rewrite set_cpu_sibling_map() sched/numa: Fix the new NUMA topology bits sched/numa: Rewrite the CONFIG_NUMA sched domain support sched/fair: Propagate 'struct lb_env' usage into find_busiest_group sched/fair: Add some serialization to the sched_domain load-balance walk sched/fair: Let minimally loaded cpu balance the group sched: Change rq->nr_running to unsigned int x86/numa: Check for nonsensical topologies on real hw as well x86/numa: Hard partition cpu topology masks on node boundaries x86/numa: Allow specifying node_distance() for numa=fake x86/sched: Make mwait_usable() heed to "idle=" kernel parameters properly sched: Update documentation and comments sched_rt: Avoid unnecessary dequeue and enqueue of pushable tasks in set_cpus_allowed_rt()
2012-05-22Merge branch 'for-3.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu updates from Tejun Heo: "Contains Alex Shi's three patches to remove percpu_xxx() which overlap with this_cpu_xxx(). There shouldn't be any functional change." * 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: percpu: remove percpu_xxx() functions x86: replace percpu_xxx funcs with this_cpu_xxx net: replace percpu_xxx funcs with this_cpu_xxx or __this_cpu_xxx
2012-05-16x86, fpu: drop the fpu state during thread exitSuresh Siddha
There is no need to save any active fpu state to the task structure memory if the task is dead. Just drop the state instead. For example, this saved some 1770 xsave's during the system boot of a two socket Xeon system. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1336692811-30576-4-git-send-email-suresh.b.siddha@intel.com Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-16fork: move the real prepare_to_copy() users to arch_dup_task_struct()Suresh Siddha
Historical prepare_to_copy() is mostly a no-op, duplicated for majority of the architectures and the rest following the x86 model of flushing the extended register state like fpu there. Remove it and use the arch_dup_task_struct() instead. Suggested-by: Oleg Nesterov <oleg@redhat.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.com Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Chris Zankel <chris@zankel.net> Cc: Richard Henderson <rth@twiddle.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-14x86: replace percpu_xxx funcs with this_cpu_xxxAlex Shi
Since percpu_xxx() serial functions are duplicated with this_cpu_xxx(). Removing percpu_xxx() definition and replacing them by this_cpu_xxx() in code. There is no function change in this patch, just preparation for later percpu_xxx serial function removing. On x86 machine the this_cpu_xxx() serial functions are same as __this_cpu_xxx() without no unnecessary premmpt enable/disable. Thanks for Stephen Rothwell, he found and fixed a i386 build error in the patch. Also thanks for Andrew Morton, he kept updating the patchset in Linus' tree. Signed-off-by: Alex Shi <alex.shi@intel.com> Acked-by: Christoph Lameter <cl@gentwo.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-05-09x86: Avoid double stack traces with show_regs()Jan Beulich
What was called show_registers() so far already showed a stack trace for kernel faults, and kernel_stack_pointer() isn't even valid to be used for faults from user mode, hence it was pointless for show_regs() to call show_trace() after show_registers(). Simply rename show_registers() to show_regs() and eliminate the old definition. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/4FAA3D3902000078000826E1@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-08x86: Use common threadinfo allocatorThomas Gleixner
The only difference is the free_thread_info function, which frees xstate. Use the new arch_release_task_struct() function instead and switch over to the core allocator. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20120505150141.559556763@linutronix.de Cc: x86@kernel.org
2012-05-08x86: Use kick_all_cpus_sync()Thomas Gleixner
Use kick_all_cpus_sync() and remove cpu_idle_wait(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120507175652.190382227@linutronix.de Cc: x86@kernel.org
2012-05-07x86/sched: Make mwait_usable() heed to "idle=" kernel parameters properlySrivatsa S. Bhat
The checks that exist in mwait_usable() for "idle=" kernel parameters are insufficient. As a result, mwait_usable() can return 1 even if "idle=nomwait" or "idle=poll" or "idle=halt" parameters are passed. Of these cases, incorrect handling of idle=nomwait is a universal problem since mwait can get used for usual CPU idling. However the rest of the cases are problematic only during CPU Hotplug (offline) because, in the CPU offline path, the function mwait_play_dead() is called, which might result in mwait being used in the offline CPUs, if mwait_usable() happens to return 1. Fix these issues by checking for the boot time "idle=" kernel parameter properly in mwait_usable(). The first issue (usual cpu idling) is demonstrated below: Before applying the patch (dmesg snippet): [ 0.000000] Command line: [...] idle=nomwait [ 0.000000] Kernel command line: [...] idle=nomwait [ 0.000000] RCU dyntick-idle grace-period acceleration is enabled. [ 0.140606] using mwait in idle threads. <======= mwait being used [ 4.303986] cpuidle: using governor ladder [ 4.308232] cpuidle: using governor menu After applying the patch: [ 0.000000] Command line: [...] idle=nomwait [ 0.000000] Kernel command line: [...] idle=nomwait [ 0.000000] RCU dyntick-idle grace-period acceleration is enabled. [ 4.264100] cpuidle: using governor ladder [ 4.268342] cpuidle: using governor menu Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: venki@google.com Cc: suresh.b.siddha@intel.com Cc: Borislav Petkov <bp@amd64.org> Cc: lenb@kernel.org Cc: Rafael J. Wysocki <rjw@sisk.pl> Link: http://lkml.kernel.org/r/4F9E37B8.30001@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-05x86: Use generic init_taskThomas Gleixner
Same code. Use the generic version. The special Makefile treatment is pointless anyway as init_task.o contains only data which is handled by the linker script. So no point on being treated like head text. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20120503085035.739963562@linutronix.de Cc: x86@kernel.org
2012-03-30x86: Remove the ancient and deprecated disable_hlt() and enable_hlt() facilityLen Brown
The X86_32-only disable_hlt/enable_hlt mechanism was used by the 32-bit floppy driver. Its effect was to replace the use of the HLT instruction inside default_idle() with cpu_relax() - essentially it turned off the use of HLT. This workaround was commented in the code as: "disable hlt during certain critical i/o operations" "This halt magic was a workaround for ancient floppy DMA wreckage. It should be safe to remove." H. Peter Anvin additionally adds: "To the best of my knowledge, no-hlt only existed because of flaky power distributions on 386/486 systems which were sold to run DOS. Since DOS did no power management of any kind, including HLT, the power draw was fairly uniform; when exposed to the much hhigher noise levels you got when Linux used HLT caused some of these systems to fail. They were by far in the minority even back then." Alan Cox further says: "Also for the Cyrix 5510 which tended to go castors up if a HLT occurred during a DMA cycle and on a few other boxes HLT during DMA tended to go astray. Do we care ? I doubt it. The 5510 was pretty obscure, the 5520 fixed it, the 5530 is probably the oldest still in any kind of use." So, let's finally drop this. Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Josh Boyer <jwboyer@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Stephen Hemminger <shemminger@vyatta.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/n/tip-3rhk9bzf0x9rljkv488tloib@git.kernel.org [ If anyone cares then alternative instruction patching could be used to replace HLT with a one-byte NOP instruction. Much simpler. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-03-29Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 updates from Ingo Molnar. This touches some non-x86 files due to the sanitized INLINE_SPIN_UNLOCK config usage. Fixed up trivial conflicts due to just header include changes (removing headers due to cpu_idle() merge clashing with the <asm/system.h> split). * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/amd: Be more verbose about LVT offset assignments x86, tls: Off by one limit check x86/ioapic: Add io_apic_ops driver layer to allow interception x86/olpc: Add debugfs interface for EC commands x86: Merge the x86_32 and x86_64 cpu_idle() functions x86/kconfig: Remove CONFIG_TR=y from the defconfigs x86: Stop recursive fault in print_context_stack after stack overflow x86/io_apic: Move and reenable irq only when CONFIG_GENERIC_PENDING_IRQ=y x86/apic: Add separate apic_id_valid() functions for selected apic drivers locking/kconfig: Simplify INLINE_SPIN_UNLOCK usage x86/kconfig: Update defconfigs x86: Fix excessive MSR print out when show_msr is not specified
2012-03-28Disintegrate asm/system.h for X86David Howells
Disintegrate asm/system.h for X86. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> cc: x86@kernel.org
2012-03-26x86: Merge the x86_32 and x86_64 cpu_idle() functionsRichard Weinberger
Both functions are mostly identical. The differences are: - x86_32's cpu_idle() makes use of check_pgt_cache(), which is a nop on both x86_32 and x86_64. - x86_64's cpu_idle() uses enter/__exit_idle/(), on x86_32 these function are a nop. - In contrast to x86_32, x86_64 calls rcu_idle_enter/exit() in the innermost loop because idle notifications need RCU. Calling these function on x86_32 also in the innermost loop does not hurt. So we can merge both functions. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: paulmck@linux.vnet.ibm.com Cc: josh@joshtriplett.org Cc: tj@kernel.org Link: http://lkml.kernel.org/r/1332709204-22496-1-git-send-email-richard@nod.at Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-03-22Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/fpu changes from Ingo Molnar. * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: i387: Split up <asm/i387.h> into exported and internal interfaces i387: Uninline the generic FP helpers that we expose to kernel modules
2012-02-21i387: Split up <asm/i387.h> into exported and internal interfacesLinus Torvalds
While various modules include <asm/i387.h> to get access to things we actually *intend* for them to use, most of that header file was really pretty low-level internal stuff that we really don't want to expose to others. So split the header file into two: the small exported interfaces remain in <asm/i387.h>, while the internal definitions that are only used by core architecture code are now in <asm/fpu-internal.h>. The guiding principle for this was to expose functions that we export to modules, and leave them in <asm/i387.h>, while stuff that is used by task switching or was marked GPL-only is in <asm/fpu-internal.h>. The fpu-internal.h file could be further split up too, especially since arch/x86/kvm/ uses some of the remaining stuff for its module. But that kvm usage should probably be abstracted out a bit, and at least now the internal FPU accessor functions are much more contained. Even if it isn't perhaps as contained as it _could_ be. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202211340330.5354@i5.linux-foundation.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-02-13x86/tracing: Denote the power and cpuidle tracepoints as _rcuidle()Steven Rostedt
The power and cpuidle tracepoints are called within a rcu_idle_exit() section, and must be denoted with the _rcuidle() version of the tracepoint. Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-12-06x86: Fix rflags in FAKE_STACK_FRAMESeiichi Ikarashi
The x86_64 kernel pushes the fake kernel stack in arch/x86/kernel/entry_64.S:FAKE_STACK_FRAME, and rflags register in it does not conform to the specification. Although Intel's manual[1] says bit 1 of it shall be set to 1, this bit is cleared to 0 on pushing the fake stack. [1] Intel(R) 64 and IA-32 Architectures Software Developer's Manual Vol.1 3-21 Figure 3-8. EFLAGS Register If it is not on purpose, it is better to be fixed, because it can lead some tools misunderstanding the stack frame. For example, "crash" utility[2] actually detects it and warns you like below: RIP: ffffffff8005dfa2 RSP: ffff8104ce0c7f58 RFLAGS: 00000200 [...] bt: WARNING: possibly bogus exception frame Signed-off-by: Seiichi Ikarashi <s.ikarashi@jp.fujitsu.com> Tested-by: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-03xen/pm_idle: Make pm_idle be default_idle under Xen.Konrad Rzeszutek Wilk
The idea behind commit d91ee5863b71 ("cpuidle: replace xen access to x86 pm_idle and default_idle") was to have one call - disable_cpuidle() which would make pm_idle not be molested by other code. It disallows cpuidle_idle_call to be set to pm_idle (which is excellent). But in the select_idle_routine() and idle_setup(), the pm_idle can still be set to either: amd_e400_idle, mwait_idle or default_idle. This depends on some CPU flags (MWAIT) and in AMD case on the type of CPU. In case of mwait_idle we can hit some instances where the hypervisor (Amazon EC2 specifically) sets the MWAIT and we get: Brought up 2 CPUs invalid opcode: 0000 [#1] SMP Pid: 0, comm: swapper Not tainted 3.1.0-0.rc6.git0.3.fc16.x86_64 #1 RIP: e030:[<ffffffff81015d1d>] [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4 ... Call Trace: [<ffffffff8100e2ed>] cpu_idle+0xae/0xe8 [<ffffffff8149ee78>] cpu_bringup_and_idle+0xe/0x10 RIP [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4 RSP <ffff8801d28ddf10> In the case of amd_e400_idle we don't get so spectacular crashes, but we do end up making an MSR which is trapped in the hypervisor, and then follow it up with a yield hypercall. Meaning we end up going to hypervisor twice instead of just once. The previous behavior before v3.0 was that pm_idle was set to default_idle regardless of select_idle_routine/idle_setup. We want to do that, but only for one specific case: Xen. This patch does that. Fixes RH BZ #739499 and Ubuntu #881076 Reported-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-23x86, mm, trivial: Remove unnecessary get_order() in free_thread_info()Zhao Jin
Because THREAD_SIZE is defined as PAGE_SIZE << THREAD_ORDER on x86, the call of get_order(THREAD_SIZE) can be replaced with THREAD_ORDER. Signed-off-by: Zhao Jin <cronozhj@gmail.com> Link: http://lkml.kernel.org/r/4E4FB5A9.700@gmail.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>