summaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/process.c
Commit message (Collapse)AuthorAgeFilesLines
* [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/machRussell King2008-08-071-1/+1
| | | | | | This just leaves include/asm-arm/plat-* to deal with. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge branch 'linus' into timers/nohzIngo Molnar2008-07-181-3/+1
|\
| * [ARM] dyntick: Remove obsolete and unused ARM dyntick supportRussell King2008-05-121-3/+1
| | | | | | | | | | | | | | | | | | dyntick is superseded by the clocksource/clockevent infrastructure, using the NO_HZ configuration option. No one implements dyntick on ARM anymore, so it's pointless keeping it around. Remove dyntick support. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | nohz: prevent tick stop outside of the idle loopThomas Gleixner2008-07-181-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jack Ren and Eric Miao tracked down the following long standing problem in the NOHZ code: scheduler switch to idle task enable interrupts Window starts here ----> interrupt happens (does not set NEED_RESCHED) irq_exit() stops the tick ----> interrupt happens (does set NEED_RESCHED) return from schedule() cpu_idle(): preempt_disable(); Window ends here The interrupts can happen at any point inside the race window. The first interrupt stops the tick, the second one causes the scheduler to rerun and switch away from idle again and we end up with the tick disabled. The fact that it needs two interrupts where the first one does not set NEED_RESCHED and the second one does made the bug obscure and extremly hard to reproduce and analyse. Kudos to Jack and Eric. Solution: Limit the NOHZ functionality to the idle loop to make sure that we can not run into such a situation ever again. cpu_idle() { preempt_disable(); while(1) { tick_nohz_stop_sched_tick(1); <- tell NOHZ code that we are in the idle loop while (!need_resched()) halt(); tick_nohz_restart_sched_tick(); <- disables NOHZ mode preempt_enable_no_resched(); schedule(); preempt_disable(); } } In hindsight we should have done this forever, but ... /me grabs a large brown paperbag. Debugged-by: Jack Ren <jack.ren@marvell.com>, Debugged-by: eric miao <eric.y.miao@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* aout: remove unnecessary inclusions of {asm, linux}/a.out.hDavid Howells2008-02-081-1/+0
| | | | | | | | | | Remove now unnecessary inclusions of {asm,linux}/a.out.h. [akpm@linux-foundation.org: fix alpha build] Signed-off-by: David Howells <dhowells@redhat.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUTDavid Howells2008-02-081-29/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Suppress A.OUT library support if CONFIG_ARCH_SUPPORTS_AOUT is not set. Not all architectures support the A.OUT binfmt, so the ELF binfmt should not be permitted to go looking for A.OUT libraries to load in such a case. Not only that, but under such conditions A.OUT core dumps are not produced either. To make this work, this patch also does the following: (1) Makes the existence of the contents of linux/a.out.h contingent on CONFIG_ARCH_SUPPORTS_AOUT. (2) Renames dump_thread() to aout_dump_thread() as it's only called by A.OUT core dumping code. (3) Moves aout_dump_thread() into asm/a.out-core.h and makes it inline. This is then included only where needed. This means that this bit of arch code will be stored in the appropriate A.OUT binfmt module rather than the core kernel. (4) Drops A.OUT support for Blackfin (according to Mike Frysinger it's not needed) and FRV. This patch depends on the previous patch to move STACK_TOP[_MAX] out of asm/a.out.h and into asm/processor.h as they're required whether or not A.OUT format is available. [jdike@addtoit.com: uml: re-remove accidentally restored code] Signed-off-by: David Howells <dhowells@redhat.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Use helpers to obtain task pid in printks (arch code)Alexey Dobriyan2007-10-191-1/+1
| | | | | | | | | | | | | | | One of the easiest things to isolate is the pid printed in kernel log. There was a patch, that made this for arch-independent code, this one makes so for arch/xxx files. It took some time to cross-compile it, but hopefully these are all the printks in arch code. Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [ARM] 4453/1: Fully Decode ARM instruction set state in show_regs() tombstoneGeorge G. Davis2007-07-121-2/+6
| | | | | | | | | | | | The ARM show_regs() tombstone only partially decodes which ARM ISA was executing at the time a fault occurred displaying either "(T)" for the Thumb case or nothing at all for other cases. This patch therefore explicitly identifies which state the processor is in at the time of a fault: ARM, Thumb, Jazelle or JazelleEE. Signed-off-by: George G. Davis <gdavis@mvista.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] Update show_regs/oops register formatRussell King2007-06-181-28/+35
| | | | | | | | | | | | Add the kernel release and version information to the output of show_regs/oops. Add the CPU PSR register. Avoid using printk to output partial lines; always output a complete line. Re-combine the "Control" and "Table + DAC" lines after nommu separated them; we don't want to waste vertical screen space needlessly. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] 4258/2: Support for dynticks in idle loopKevin Hilman2007-04-211-0/+3
| | | | | | | | | | And, wrap timer_tick() and sysdev suspend/resume in !GENERIC_CLOCKEVENTS since clockevent layer takes care of these. Signed-off-by: Kevin Hilman <khilman@mvista.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] Remove needless linux/ptrace.h includesRussell King2007-04-211-1/+0
| | | | | | | | | Lots of places in arch/arm were needlessly including linux/ptrace.h, resumably because we used to pass a struct pt_regs to interrupt handlers. Now that we don't, all these ptrace.h includes are redundant. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] Move processor_modes[] to .../process.cRussell King2007-02-061-1/+7
| | | | | | | | | | | | | | bad_mode() currently prints the mode which caused the exception, and then causes an oops dump to be printed which again displays this information (since the CPSR in the struct pt_regs is correct.) This leads to processor_modes[] being shared between traps.c and process.c with a local declaration of it. We can clean this up by moving processor_modes[] to process.c and removing the duplication, resulting in processor_modes[] becoming static. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] 3911/2: Simplify alloc_thread_info on ARMPaul Gortmaker2006-11-301-61/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove ARM local cache of 4 struct thread_info. Can cause oops under certain circumstances. Russell indicated the original optimization was required on older kernels to avoid thread starvation on memory fragmentation, but may no longer be required. I've updated the patch to 19rc4 and ensured no <config.h> dain-bramage slipped in this time (sorry about that). Original description follows: I was given some test results which pointed to an Oops in alloc_thread_info (happened 2x), and after looking at the code, I see that ARM has its own local cache of 4 struct thread_info. There wasn't any clear (to me) synchronization between the alloc_thread_info and the free_thread_info. I looked over the other arch, and they all simply allocate them on an as needed basis, so I simplified the ARM to do the same, based on the other arch (e.g. PPC) and the folks doing the testing have indicated that this fixed the oops. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] nommu: manage the CP15 thingsHyok S. Choi2006-09-271-6/+16
| | | | | | | | | | | | | | | | | | | | | | | All the current CP15 access codes in ARM arch can be categorized and conditioned by the defines as follows: Related operation Safe condition a. any CP15 access !CPU_CP15 b. alignment trap CPU_CP15_MMU c. D-cache(C-bit) CPU_CP15 d. I-cache CPU_CP15 && !( CPU_ARM610 || CPU_ARM710 || CPU_ARM720 || CPU_ARM740 || CPU_XSCALE || CPU_XSC3 ) e. alternate vector CPU_CP15 && !CPU_ARM740 f. TTB CPU_CP15_MMU g. Domain CPU_CP15_MMU h. FSR/FAR CPU_CP15_MMU For example, alternate vector is supported if and only if "CPU_CP15 && !CPU_ARM740" is satisfied. Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds2006-07-021-6/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (44 commits) [ARM] 3541/2: workaround for PXA27x erratum E7 [ARM] nommu: provide a way for correct control register value selection [ARM] 3705/1: add supersection support to ioremap() [ARM] 3707/1: iwmmxt: use the generic thread notifier infrastructure [ARM] 3706/2: ep93xx: add cirrus logic edb9315a support [ARM] 3704/1: format IOP Kconfig with tabs, create more consistency [ARM] 3703/1: Add help description for ARCH_EP80219 [ARM] 3678/1: MMC: Make OMAP MMC work [ARM] 3677/1: OMAP: Update H2 defconfig [ARM] 3676/1: ARM: OMAP: Fix dmtimers and timer32k to compile on OMAP1 [ARM] Add section support to ioremap [ARM] Fix sa11x0 SDRAM selection [ARM] Set bit 4 on section mappings correctly depending on CPU [ARM] 3666/1: TRIZEPS4 [1/5] core ARM: OMAP: Multiplexing for 24xx GPMC wait pin monitoring ARM: OMAP: Fix SRAM to use MT_MEMORY instead of MT_DEVICE ARM: OMAP: Update dmtimers ARM: OMAP: Make clock variables static ARM: OMAP: Fix GPMC compilation when DEBUG is defined ARM: OMAP: Mux updates for external DMA and GPIO ...
| * [ARM] 3707/1: iwmmxt: use the generic thread notifier infrastructureLennert Buytenhek2006-07-011-6/+0
| | | | | | | | | | | | | | | | | | | | | | Patch from Lennert Buytenhek This patch makes the iWMMXt context switch hook use the generic thread notifier infrastructure that was recently merged in commit d6551e884cf66de072b81f8b6d23259462c40baf. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
|/ | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [ARM] Add thread_notify infrastructureRussell King2006-06-221-14/+10
| | | | | | | | | | | | | Some machine classes need to allow VFP support to be built into the kernel, but still allow the kernel to run even though VFP isn't present. Unfortunately, the kernel hard-codes VFP instructions into the thread switch, which prevents this being run-time selectable. Solve this by introducing a notifier which things such as VFP can hook into to be informed of events which affect the VFP subsystem (eg, creation and destruction of threads, switches between threads.) Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] 3593/1: Add reboot and shutdown handlers for Zaurus handheldsRichard Purdie2006-06-191-26/+35
| | | | | | | | | | | Patch from Richard Purdie Add functionality to allow machine specific reboot handlers on ARM. Add machine specific reboot and poweroff handlers for all PXA Zaurus models. Signed-off-by: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] arch/arm/kernel/process.c: Fix warningRussell King2006-05-161-1/+1
| | | | | | arch/arm/kernel/process.c:314: warning: assignment makes integer from pointer without a cast Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] Fix thread struct allocator for SMP caseRussell King2006-05-091-12/+25
| | | | | | | | The ARM thread struct allocator is racy on SMP systems. Fix it by turning it into a per-cpu based allocator. This also allows keeps the cache cache warm for thread structs and kernel stacks. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] unexport get_wchanAdrian Bunk2006-03-311-1/+0
| | | | | | | | The only user of get_wchan is the proc fs - and proc can't be built modular. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [ARM] 3363/1: [cleanup] process.c - fix warningsBen Dooks2006-03-151-1/+2
| | | | | | | | | | | | | | | Patch from Ben Dooks Fix the following warnings from sparse: arch/arm/kernel/process.c:86:6: warning: symbol 'default_idle' was not declared. Should it be static? arch/arm/kernel/process.c:378:5: warning: symbol 'dump_fpu' was not declared. Should it be static? Include <linux/elfcore.h> for dump_fpu() decleration, and make default_idle() static as it is not used outside the file. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] arm: task_stack_page()Al Viro2006-01-121-1/+1
| | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] arm: end_of_stack()Al Viro2006-01-121-1/+1
| | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] arm: task_pt_regs()Al Viro2006-01-121-3/+2
| | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] arm: task_thread_info()Al Viro2006-01-121-2/+2
| | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [ARM] Cleanup ARM includesRussell King2006-01-031-2/+1
| | | | | | | | | | | | | | | | arch/arm/kernel/entry-armv.S has contained a comment suggesting that asm/hardware.h and asm/arch/irqs.h should be moved into the asm/arch/entry-macro.S include. So move the includes to these two files as required. Add missing includes (asm/hardware.h, asm/io.h) to asm/arch/system.h includes which use those facilities, and remove asm/io.h from kernel/process.c. Remove other unnecessary includes from arch/arm/kernel, arch/arm/mm and arch/arm/mach-footbridge. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds2005-11-091-1/+1
|\
| * [ARM] 3100/1: simplify a pointer computationNicolas Pitre2005-11-091-1/+1
| | | | | | | | | | | | | | | | | | Patch from Nicolas Pitre Looks clearer this way. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | [PATCH] sched: resched and cpu_idle reworkNick Piggin2005-11-091-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce confusion, and make their semantics rigid. Improves efficiency of resched_task and some cpu_idle routines. * In resched_task: - TIF_NEED_RESCHED is only cleared with the task's runqueue lock held, and as we hold it during resched_task, then there is no need for an atomic test and set there. The only other time this should be set is when the task's quantum expires, in the timer interrupt - this is protected against because the rq lock is irq-safe. - If TIF_NEED_RESCHED is set, then we don't need to do anything. It won't get unset until the task get's schedule()d off. - If we are running on the same CPU as the task we resched, then set TIF_NEED_RESCHED and no further action is required. - If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set after TIF_NEED_RESCHED has been set, then we need to send an IPI. Using these rules, we are able to remove the test and set operation in resched_task, and make clear the previously vague semantics of POLLING_NRFLAG. * In idle routines: - Enter cpu_idle with preempt disabled. When the need_resched() condition becomes true, explicitly call schedule(). This makes things a bit clearer (IMO), but haven't updated all architectures yet. - Many do a test and clear of TIF_NEED_RESCHED for some reason. According to the resched_task rules, this isn't needed (and actually breaks the assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock held). So remove that. Generally one less locked memory op when switching to the idle thread. - Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner most polling idle loops. The above resched_task semantics allow it to be set until before the last time need_resched() is checked before going into a halt requiring interrupt wakeup. Many idle routines simply never enter such a halt, and so POLLING_NRFLAG can be always left set, completely eliminating resched IPIs when rescheduling the idle task. POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Con Kolivas <kernel@kolivas.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] sched: disable preempt in idle tasksNick Piggin2005-11-091-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Run idle threads with preempt disabled. Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()). How did it ever work before? Might fix the CPU hotplugging hang which Nigel Cunningham noted. We think the bug hits if the idle thread is preempted after checking need_resched() and before going to sleep, then the CPU offlined. After calling stop_machine_run, the CPU eventually returns from preemption and into the idle thread and goes to sleep. The CPU will continue executing previous idle and have no chance to call play_dead. By disabling preemption until we are ready to explicitly schedule, this bug is fixed and the idle threads generally become more robust. From: alexs <ashepard@u.washington.edu> PPC build fix From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp> MIPS build fix Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [ARM SMP] Add hotplug CPU infrastructureRussell King2005-11-021-0/+9
| | | | | | | This patch adds the infrastructure to support hotplug CPU on ARM platforms. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] Don't export machine_restart, machine_halt, or machine_power_off.Eric W. Biederman2005-07-261-4/+0
| | | | | | | | | | | | machine_restart, machine_halt and machine_power_off are machine specific hooks deep into the reboot logic, that modules have no business messing with. Usually code should be calling kernel_restart, kernel_halt, kernel_power_off, or emergency_restart. So don't export machine_restart, machine_halt, and machine_power_off so we can catch buggy users. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ARM: Add VST idle loop callRussell King2005-06-271-1/+4
| | | | | | | This call allows the dynamic tick support to reprogram the timer immediately before the CPU idles. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] ARM: Fix kernel stack offset calculationsRussell King2005-05-051-13/+12
| | | | | | | | | | | | Various places in the ARM kernel implicitly assumed that kernel stacks are always 8K due to hard coded constants. Replace these constants with definitions. Correct the allowable range of kernel stack pointer values within the allocation. Arrange for the entire kernel stack to be zeroed, not just the upper 4K if CONFIG_DEBUG_STACK_USAGE is set. Signed-off-by: Russell King <rmk@arm.linux.org.uk>
* [PATCH] ARM: showregsRussell King2005-04-171-4/+11
| | | | | | | | Fix show_regs() to provide a backtrace. Provide a new __show_regs() function which implements the common subset of show_regs() and die(). Add prototypes to asm-arm/system.h Signed-off-by: Russell King <rmk@arm.linux.org.uk>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+460
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
OpenPOWER on IntegriCloud