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* Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2015-09-011-15/+15
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm changes from Ingo Molnar: "The biggest changes in this cycle were: - Revamp, simplify (and in some cases fix) Time Stamp Counter (TSC) primitives. (Andy Lutomirski) - Add new, comprehensible entry and exit handlers written in C. (Andy Lutomirski) - vm86 mode cleanups and fixes. (Brian Gerst) - 32-bit compat code cleanups. (Brian Gerst) The amount of simplification in low level assembly code is already palpable: arch/x86/entry/entry_32.S | 130 +---- arch/x86/entry/entry_64.S | 197 ++----- but more simplifications are planned. There's also the usual laudry mix of low level changes - see the changelog for details" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (83 commits) x86/asm: Drop repeated macro of X86_EFLAGS_AC definition x86/asm/msr: Make wrmsrl() a function x86/asm/delay: Introduce an MWAITX-based delay with a configurable timer x86/asm: Add MONITORX/MWAITX instruction support x86/traps: Weaken context tracking entry assertions x86/asm/tsc: Add rdtscll() merge helper selftests/x86: Add syscall_nt selftest selftests/x86: Disable sigreturn_64 x86/vdso: Emit a GNU hash x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masks x86/entry/32: Migrate to C exit path x86/entry/32: Remove 32-bit syscall audit optimizations x86/vm86: Rename vm86->v86flags and v86mask x86/vm86: Rename vm86->vm86_info to user_vm86 x86/vm86: Clean up vm86.h includes x86/vm86: Move the vm86 IRQ definitions to vm86.h x86/vm86: Use the normal pt_regs area for vm86 x86/vm86: Eliminate 'struct kernel_vm86_struct' x86/vm86: Move fields from 'struct kernel_vm86_struct' to 'struct vm86' x86/vm86: Move vm86 fields out of 'thread_struct' ...
| * locking/spinlocks: Force inlining of spinlock opsDenys Vlasenko2015-07-211-15/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With both gcc 4.7.2 and 4.9.2, sometimes GCC mysteriously doesn't inline very small functions we expect to be inlined. See: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122 In particular, with this config: http://busybox.net/~vda/kernel_config there are more than a thousand copies of tiny spinlock-related functions: $ nm --size-sort vmlinux | grep -iF ' t ' | uniq -c | grep -v '^ *1 ' | sort -rn | grep ' spin' 473 000000000000000b t spin_unlock_irqrestore 292 000000000000000b t spin_unlock 215 000000000000000b t spin_lock 134 000000000000000b t spin_unlock_irq 130 000000000000000b t spin_unlock_bh 120 000000000000000b t spin_lock_irq 106 000000000000000b t spin_lock_bh Disassembly: ffffffff81004720 <spin_lock>: ffffffff81004720: 55 push %rbp ffffffff81004721: 48 89 e5 mov %rsp,%rbp ffffffff81004724: e8 f8 4e e2 02 callq <_raw_spin_lock> ffffffff81004729: 5d pop %rbp ffffffff8100472a: c3 retq This patch fixes this via s/inline/__always_inline/ in spinlock.h. This decreases vmlinux by about 40k: text data bss dec hex filename 82375570 22255544 20627456 125258570 7774b4a vmlinux.before 82335059 22255416 20627456 125217931 776ac8b vmlinux Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Rientjes <rientjes@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Graf <tgraf@suug.ch> Link: http://lkml.kernel.org/r/1436812263-15243-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | rcu,locking: Privatize smp_mb__after_unlock_lock()Paul E. McKenney2015-08-041-10/+0
|/ | | | | | | | | | | | RCU is the only thing that uses smp_mb__after_unlock_lock(), and is likely the only thing that ever will use it, so this commit makes this macro private to RCU. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>
* documentation: memory-barriers: Fix smp_mb__before_spinlock() semanticsWill Deacon2015-05-271-1/+1
| | | | | | | | | | | | | | | | | | | | Our current documentation claims that, when followed by an ACQUIRE, smp_mb__before_spinlock() orders prior loads against subsequent loads and stores, which isn't the intent. This commit therefore fixes the documentation to state that this sequence orders only prior stores against subsequent loads and stores. In addition, the original intent of smp_mb__before_spinlock() was to only order prior loads against subsequent stores, however, people have started using it as if it ordered prior loads against subsequent loads and stores. This commit therefore also updates smp_mb__before_spinlock()'s header comment to reflect this new reality. Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* spinlock: Add spin_lock_bh_nested()Thomas Graf2015-01-031-0/+8
| | | | | Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* locking/spinlocks: Always evaluate the second argument of spin_lock_nested()Bart Van Assche2014-08-131-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | Evaluating a macro argument only if certain configuration options have been selected is confusing and error-prone. Hence always evaluate the second argument of spin_lock_nested(). An intentional side effect of this patch is that it avoids that the following warning is reported for netif_addr_lock_nested() when building with CONFIG_DEBUG_LOCK_ALLOC=n and with W=1: include/linux/netdevice.h: In function 'netif_addr_lock_nested': include/linux/netdevice.h:2865:6: warning: variable 'subclass' set but not used [-Wunused-but-set-variable] int subclass = SINGLE_DEPTH_NESTING; ^ Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/53E4A7F8.1040700@acm.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking: Add an smp_mb__after_unlock_lock() for UNLOCK+BLOCK barrierPaul E. McKenney2013-12-161-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | The Linux kernel has traditionally required that an UNLOCK+LOCK pair act as a full memory barrier when either (1) that UNLOCK+LOCK pair was executed by the same CPU or task, or (2) the same lock variable was used for the UNLOCK and LOCK. It now seems likely that very few places in the kernel rely on this full-memory-barrier semantic, and with the advent of queued locks, providing this semantic either requires complex reasoning, or for some architectures, added overhead. This commit therefore adds a smp_mb__after_unlock_lock(), which may be placed after a LOCK primitive to restore the full-memory-barrier semantic. All definitions are currently no-ops, but will be upgraded for some architectures when queued locks arrive. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <linux-arch@vger.kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1386799151-2219-5-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched: fix the theoretical signal_wake_up() vs schedule() raceOleg Nesterov2013-08-131-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is only theoretical, but after try_to_wake_up(p) was changed to check p->state under p->pi_lock the code like __set_current_state(TASK_INTERRUPTIBLE); schedule(); can miss a signal. This is the special case of wait-for-condition, it relies on try_to_wake_up/schedule interaction and thus it does not need mb() between __set_current_state() and if(signal_pending). However, this __set_current_state() can move into the critical section protected by rq->lock, now that try_to_wake_up() takes another lock we need to ensure that it can't be reordered with "if (signal_pending(current))" check inside that section. The patch is actually one-liner, it simply adds smp_wmb() before spin_lock_irq(rq->lock). This is what try_to_wake_up() already does by the same reason. We turn this wmb() into the new helper, smp_mb__before_spinlock(), for better documentation and to allow the architectures to change the default implementation. While at it, kill smp_mb__after_lock(), it has no callers. Perhaps we can also add smp_mb__before/after_spinunlock() for prepare_to_wait(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'split-asm_system_h-for-linus-20120328' of ↵Linus Torvalds2012-03-281-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system Pull "Disintegrate and delete asm/system.h" from David Howells: "Here are a bunch of patches to disintegrate asm/system.h into a set of separate bits to relieve the problem of circular inclusion dependencies. I've built all the working defconfigs from all the arches that I can and made sure that they don't break. The reason for these patches is that I recently encountered a circular dependency problem that came about when I produced some patches to optimise get_order() by rewriting it to use ilog2(). This uses bitops - and on the SH arch asm/bitops.h drags in asm-generic/get_order.h by a circuituous route involving asm/system.h. The main difficulty seems to be asm/system.h. It holds a number of low level bits with no/few dependencies that are commonly used (eg. memory barriers) and a number of bits with more dependencies that aren't used in many places (eg. switch_to()). These patches break asm/system.h up into the following core pieces: (1) asm/barrier.h Move memory barriers here. This already done for MIPS and Alpha. (2) asm/switch_to.h Move switch_to() and related stuff here. (3) asm/exec.h Move arch_align_stack() here. Other process execution related bits could perhaps go here from asm/processor.h. (4) asm/cmpxchg.h Move xchg() and cmpxchg() here as they're full word atomic ops and frequently used by atomic_xchg() and atomic_cmpxchg(). (5) asm/bug.h Move die() and related bits. (6) asm/auxvec.h Move AT_VECTOR_SIZE_ARCH here. Other arch headers are created as needed on a per-arch basis." Fixed up some conflicts from other header file cleanups and moving code around that has happened in the meantime, so David's testing is somewhat weakened by that. We'll find out anything that got broken and fix it.. * tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits) Delete all instances of asm/system.h Remove all #inclusions of asm/system.h Add #includes needed to permit the removal of asm/system.h Move all declarations of free_initmem() to linux/mm.h Disintegrate asm/system.h for OpenRISC Split arch_align_stack() out from asm-generic/system.h Split the switch_to() wrapper out of asm-generic/system.h Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h Create asm-generic/barrier.h Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h Disintegrate asm/system.h for Xtensa Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt] Disintegrate asm/system.h for Tile Disintegrate asm/system.h for Sparc Disintegrate asm/system.h for SH Disintegrate asm/system.h for Score Disintegrate asm/system.h for S390 Disintegrate asm/system.h for PowerPC Disintegrate asm/system.h for PA-RISC Disintegrate asm/system.h for MN10300 ...
| * Remove all #inclusions of asm/system.hDavid Howells2012-03-281-1/+0
| | | | | | | | | | | | | | | | | | Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
| * Add #includes needed to permit the removal of asm/system.hDavid Howells2012-03-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | asm/system.h is a cause of circular dependency problems because it contains commonly used primitive stuff like barrier definitions and uncommonly used stuff like switch_to() that might require MMU definitions. asm/system.h has been disintegrated by this point on all arches into the following common segments: (1) asm/barrier.h Moved memory barrier definitions here. (2) asm/cmpxchg.h Moved xchg() and cmpxchg() here. #included in asm/atomic.h. (3) asm/bug.h Moved die() and similar here. (4) asm/exec.h Moved arch_align_stack() here. (5) asm/elf.h Moved AT_VECTOR_SIZE_ARCH here. (6) asm/switch_to.h Moved switch_to() here. Signed-off-by: David Howells <dhowells@redhat.com>
* | spinlock: macroize assert_spin_locked to avoid bug.h dependencyPaul Gortmaker2012-02-281-4/+1
|/ | | | | | | | | | | | In spinlock_api_smp.h we find a define for assert_raw_spin_locked [which uses BUG_ON]. Then assert_spin_locked (as an inline) uses it, meaning we need bug.h But rather than put linux/bug.h in such a highly used file like spinlock.h, we can just make the un-raw version also a macro. Then the required bug.h presence is limited just to those few files who are actually doing the assert testing. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> CC: Thomas Gleixner <tglx@linutronix.de>
* atomic: use <linux/atomic.h>Arun Sharma2011-07-261-1/+1
| | | | | | | | | | | | | | This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Fix common misspellingsLucas De Marchi2011-03-311-1/+1
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* Fix IRQ flag handling namingDavid Howells2010-10-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the IRQ flag handling naming. In linux/irqflags.h under one configuration, it maps: local_irq_enable() -> raw_local_irq_enable() local_irq_disable() -> raw_local_irq_disable() local_irq_save() -> raw_local_irq_save() ... and under the other configuration, it maps: raw_local_irq_enable() -> local_irq_enable() raw_local_irq_disable() -> local_irq_disable() raw_local_irq_save() -> local_irq_save() ... This is quite confusing. There should be one set of names expected of the arch, and this should be wrapped to give another set of names that are expected by users of this facility. Change this to have the arch provide: flags = arch_local_save_flags() flags = arch_local_irq_save() arch_local_irq_restore(flags) arch_local_irq_disable() arch_local_irq_enable() arch_irqs_disabled_flags(flags) arch_irqs_disabled() arch_safe_halt() Then linux/irqflags.h wraps these to provide: raw_local_save_flags(flags) raw_local_irq_save(flags) raw_local_irq_restore(flags) raw_local_irq_disable() raw_local_irq_enable() raw_irqs_disabled_flags(flags) raw_irqs_disabled() raw_safe_halt() with type checking on the flags 'arguments', and then wraps those to provide: local_save_flags(flags) local_irq_save(flags) local_irq_restore(flags) local_irq_disable() local_irq_enable() irqs_disabled_flags(flags) irqs_disabled() safe_halt() with tracing included if enabled. The arch functions can now all be inline functions rather than some of them having to be macros. Signed-off-by: David Howells <dhowells@redhat.com> [X86, FRV, MN10300] Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [Tile] Signed-off-by: Michal Simek <monstr@monstr.eu> [Microblaze] Tested-by: Catalin Marinas <catalin.marinas@arm.com> [ARM] Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [AVR] Acked-by: Tony Luck <tony.luck@intel.com> [IA-64] Acked-by: Hirokazu Takata <takata@linux-m32r.org> [M32R] Acked-by: Greg Ungerer <gerg@uclinux.org> [M68K/M68KNOMMU] Acked-by: Ralf Baechle <ralf@linux-mips.org> [MIPS] Acked-by: Kyle McMartin <kyle@mcmartin.ca> [PA-RISC] Acked-by: Paul Mackerras <paulus@samba.org> [PowerPC] Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [S390] Acked-by: Chen Liqin <liqin.chen@sunplusct.com> [Score] Acked-by: Matt Fleming <matt@console-pimps.org> [SH] Acked-by: David S. Miller <davem@davemloft.net> [Sparc] Acked-by: Chris Zankel <chris@zankel.net> [Xtensa] Reviewed-by: Richard Henderson <rth@twiddle.net> [Alpha] Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp> [H8300] Cc: starvik@axis.com [CRIS] Cc: jesper.nilsson@axis.com [CRIS] Cc: linux-cris-kernel@axis.com
* Merge branch 'for-35' of git://repo.or.cz/linux-kbuildLinus Torvalds2010-06-011-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-35' of git://repo.or.cz/linux-kbuild: (81 commits) kbuild: Revert part of e8d400a to resolve a conflict kbuild: Fix checking of scm-identifier variable gconfig: add support to show hidden options that have prompts menuconfig: add support to show hidden options which have prompts gconfig: remove show_debug option gconfig: remove dbg_print_ptype() and dbg_print_stype() kconfig: fix zconfdump() kconfig: some small fixes add random binaries to .gitignore kbuild: Include gen_initramfs_list.sh and the file list in the .d file kconfig: recalc symbol value before showing search results .gitignore: ignore *.lzo files headerdep: perlcritic warning scripts/Makefile.lib: Align the output of LZO kbuild: Generate modules.builtin in make modules_install Revert "kbuild: specify absolute paths for cscope" kbuild: Do not unnecessarily regenerate modules.builtin headers_install: use local file handles headers_check: fix perl warnings export_report: fix perl warnings ...
| * Rename .text.lock to .text..lock.Denys Vlasenko2010-03-031-1/+1
| | | | | | | | | | Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
* | locking: Make sparse work with inline spinlocks and rwlocksLuca Barbieri2010-03-131-5/+8
|/ | | | | | | | | | | | | Currently sparse does not work with inline spinlock and rwlock functions. The problem is that they do not use the __acquires/__releases out-of-line functions, but use inline functions with no sparse annotations. This patch adds the appropriate annotations to make it work properly. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* locking: Cleanup the name space completelyThomas Gleixner2009-12-141-17/+20
| | | | | | | | | | | | Make the name space hierarchy of locking functions consistent: raw_spin* -> _raw_spin* -> __raw_spin* No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
* locking: Further name space cleanupsThomas Gleixner2009-12-141-8/+8
| | | | | | | | | | | | | | | The name space hierarchy for the internal lock functions is now a bit backwards. raw_spin* functions map to _spin* which use __spin*, while we would like to have _raw_spin* and __raw_spin*. _raw_spin* is already used by lock debugging, so rename those funtions to do_raw_spin* to free up the _raw_spin* name space. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
* locking: Implement new raw_spinlockThomas Gleixner2009-12-141-64/+194
| | | | | | | | | | | | | | | | Now that the raw_spin name space is freed up, we can implement raw_spinlock and the related functions which are used to annotate the locks which are not converted to sleeping spinlocks in preempt-rt. A side effect is that only such locks can be used with the low level lock fsunctions which circumvent lockdep. For !rt spin_* functions are mapped to the raw_spin* implementations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
* locking: Convert raw_rwlock to arch_rwlockThomas Gleixner2009-12-141-2/+2
| | | | | | | | | | | | | | Not strictly necessary for -rt as -rt does not have non sleeping rwlocks, but it's odd to not have a consistent naming convention. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
* locking: Convert __raw_spin* functions to arch_spin*Thomas Gleixner2009-12-141-11/+11
| | | | | | | | | | Name space cleanup. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
* locking: Convert raw_spinlock to arch_spinlockThomas Gleixner2009-12-141-2/+2
| | | | | | | | | | | | | | | | | | | The raw_spin* namespace was taken by lockdep for the architecture specific implementations. raw_spin_* would be the ideal name space for the spinlocks which are not converted to sleeping locks in preempt-rt. Linus suggested to convert the raw_ to arch_ locks and cleanup the name space instead of using an artifical name like core_spin, atomic_spin or whatever No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
* locking: Split rwlock from spinlock headersThomas Gleixner2009-12-141-92/+8
| | | | | | | | | | | | Move the rwlock defines and inlines into separate header files. This makes the selection for -rt easier. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
* locking: Use __[SPIN|RW]_LOCK_UNLOCKED in [spin|rw]_lock_init()Thomas Gleixner2009-11-241-2/+2
| | | | | | | SPIN_LOCK_UNLOCKED and RW_LOCK_UNLOCKED are deprecated. Replace them with the __*_LOCK_UNLOCKED variants. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* locking: Remove unused prototypeThomas Gleixner2009-11-241-2/+0
| | | | | | | commit 910067d1(remove generic__raw_read_trylock()) removed the implementation but left the prototype around. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* locking: Simplify spinlock inliningHeiko Carstens2009-08-311-40/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For !DEBUG_SPINLOCK && !PREEMPT && SMP the spin_unlock() functions were always inlined by using special defines which would call the __raw* functions. The out-of-line variants for these functions would be generated anyway. Use the new per unlock/locking variant mechanism to force inlining of the unlock functions like before. This is not a functional change, we just get rid of one additional way to force inlining. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Horst Hartmann <horsth@linux.vnet.ibm.com> Cc: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: David Miller <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: <linux-arch@vger.kernel.org> LKML-Reference: <20090831124418.848735034@de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* locking: Move spinlock function bodies to header fileHeiko Carstens2009-08-311-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | Move spinlock function bodies to header file by creating a static inline version of each variant. Use the inline version on the out-of-line code. This shouldn't make any difference besides that the spinlock code can now be used to generate inlined spinlock code. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Horst Hartmann <horsth@linux.vnet.ibm.com> Cc: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: David Miller <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: <linux-arch@vger.kernel.org> LKML-Reference: <20090831124417.859022429@de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* memory barrier: adding smp_mb__after_lockJiri Olsa2009-07-091-0/+5
| | | | | | | | | | | | Adding smp_mb__after_lock define to be used as a smp_mb call after a lock. Making it nop for x86, since {read|write|spin}_lock() on x86 are full memory barriers. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Allow rwlocks to re-enable interruptsRobin Holt2009-04-021-0/+6
| | | | | | | | | | | | | | | | | Pass the original flags to rwlock arch-code, so that it can re-enable interrupts if implemented for that architecture. Initially, make __raw_read_lock_flags and __raw_write_lock_flags stubs which just do the same thing as non-flags variants. Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Robin Holt <holt@sgi.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <linux-arch@vger.kernel.org> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: spinlocks: define dummy __raw_spin_is_contendedKyle McMartin2009-02-091-0/+5
| | | | | | | | | | | | | Architectures other than mips and x86 are not using ticket spinlocks. Therefore, the contention on the lock is meaningless, since there is nobody known to be waiting on it (arguably /fairly/ unfair locks). Dummy it out to return 0 on other architectures. Signed-off-by: Kyle McMartin <kyle@redhat.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lockdep: spin_lock_nest_lock()Peter Zijlstra2008-08-111-0/+6
| | | | | | | | | | | | | Expose the new lock protection lock. This can be used to annotate places where we take multiple locks of the same class and avoid deadlocks by always taking another (top-level) lock first. NOTE: we're still bound to the MAX_LOCK_DEPTH (48) limit. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* locking: add typecheck on irqsave and friends for correct flagsSteven Rostedt2008-07-251-16/+56
| | | | | | | | | | | | | | | | There haave been several areas in the kernel where an int has been used for flags in local_irq_save() and friends instead of a long. This can cause some hard to debug problems on some architectures. This patch adds a typecheck inside the irqsave and restore functions to flag these cases. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: build fix] Signed-off-by: Steven Rostedt <srostedt@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locking: remove unused double_spin_lock()Oleg Nesterov2008-04-171-37/+0
| | | | | | | | | | | | | double_spin_lock() has no callers, and it can't be used without additional lockdep annotations, remove it. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Spell out behavior of atomic_dec_and_lock() in kerneldocJ. Bruce Fields2008-04-111-0/+3
| | | | | | | A little more detail here wouldn't hurt. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Remove fastcall from linux/includeHarvey Harrison2008-02-081-1/+1
| | | | | | | [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* spinlock: lockbreak cleanupNick Piggin2008-01-301-0/+6
| | | | | | | | | | | | | | | | | | | | The break_lock data structure and code for spinlocks is quite nasty. Not only does it double the size of a spinlock but it changes locking to a potentially less optimal trylock. Put all of that under CONFIG_GENERIC_LOCKBREAK, and introduce a __raw_spin_is_contended that uses the lock data itself to determine whether there are waiters on the lock, to be used if CONFIG_GENERIC_LOCKBREAK is not set. Rename need_lockbreak to spin_needbreak, make it use spin_is_contended to decouple it from the spinlock implementation, and make it typesafe (rwlocks do not have any need_lockbreak sites -- why do they even get bloated up with that break_lock then?). Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* introduce write_trylock_irqsave()Satyam Sharma2007-07-161-0/+7
| | | | | | | | | | | Introduce a write_trylock_irqsave() implementation. Similar in style to the implementation of spin_trylock_irqsave() in mainline. Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in> Cc: Sripathi Kodi <sripathik@in.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] timer/hrtimer: take per cpu locks in sane orderHeiko Carstens2007-03-051-0/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Doing something like this on a two cpu system # echo 0 > /sys/devices/system/cpu/cpu0/online # echo 1 > /sys/devices/system/cpu/cpu0/online # echo 0 > /sys/devices/system/cpu/cpu1/online will give me this: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.21-rc2-g562aa1d4-dirty #7 ------------------------------------------------------- bash/1282 is trying to acquire lock: (&cpu_base->lock_key){.+..}, at: [<000000000005f17e>] hrtimer_cpu_notify+0xc6/0x240 but task is already holding lock: (&cpu_base->lock_key#2){.+..}, at: [<000000000005f174>] hrtimer_cpu_notify+0xbc/0x240 which lock already depends on the new lock. This happens because we have the following code in kernel/hrtimer.c: migrate_hrtimers(int cpu) [...] old_base = &per_cpu(hrtimer_bases, cpu); new_base = &get_cpu_var(hrtimer_bases); [...] spin_lock(&new_base->lock); spin_lock(&old_base->lock); Which means the spinlocks are taken in an order which depends on which cpu gets shut down from which other cpu. Therefore lockdep complains that there might be an ABBA deadlock. Since migrate_hrtimers() gets only called on cpu hotplug it's safe to assume that it isn't executed concurrently on a The same problem exists in kernel/timer.c: migrate_timers(). As pointed out by Christian Borntraeger one possible solution to avoid the locking order complaints would be to make sure that the locks are always taken in the same order. E.g. by taking the lock of the cpu with the lower number first. To achieve this we introduce two new spinlock functions double_spin_lock and double_spin_unlock which lock or unlock two locks in a given order. Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: John Stultz <johnstul@us.ibm.com> Cc: Christian Borntraeger <cborntra@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] Fix sparse annotation of spin unlock macros in one casePavel Roskin2007-02-111-9/+24
| | | | | | | | | | | SMP systems without premption and spinlock debugging enabled use unlock macros that don't tell sparse that the lock is being released. Add sparse annotations in this case. Signed-off-by: Pavel Roskin <proski@gnu.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] add bottom_half.hAndrew Morton2006-12-071-0/+1
| | | | | | | | | | | | | | | | | | | | With CONFIG_SMP=n: drivers/input/ff-memless.c:384: warning: implicit declaration of function 'local_bh_disable' drivers/input/ff-memless.c:393: warning: implicit declaration of function 'local_bh_enable' Really linux/spinlock.h should include linux/interrupt.h. But interrupt.h includes sched.h which will need spinlock.h. So the patch breaks the _bh declarations out into a separate header and includes it in both interrupt.h and spinlock.h. Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Andi Kleen <ak@suse.de> Cc: <stable@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Revert "[PATCH] Enforce "unsigned long flags;" when spinlocking"Linus Torvalds2006-11-261-54/+15
| | | | | | | | | | | | | | | This reverts commit ee3ce191e8eaa4cc15c51a28b34143b36404c4f5, since it broke on at least ARM, MIPS and PA-RISC due to complicated header file dependencies. Conflicts in include/linux/spinlock.h (due to the "nested" variety fixes) fixed up by hand. Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@parisc-linux.org> Cc: Russell King <rmk+lkml@arm.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] lockdep: spin_lock_irqsave_nested()Arjan van de Ven2006-11-251-0/+18
| | | | | | | | | | | | | | | Introduce spin_lock_irqsave_nested(); implementation from: http://lkml.org/lkml/2006/6/1/122 Patch from: http://lkml.org/lkml/2006/9/13/258 [akpm@osdl.org: two compile fixes] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Jiri Kosina <jikos@jikos.cz> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Enforce "unsigned long flags;" when spinlockingAlexey Dobriyan2006-11-251-9/+44
| | | | | | | | | | | | | | | | | | | | | | | | Make it break or warn if you pass to spin_lock_irqsave() and friends something different from "unsigned long flags;". Suprisingly large amount of these was caught by recent commit c53421b18f205c5f97c604ae55c6a921f034b0f6 and others. Idea is largely from FRV typechecking. Suggestions from Andrew Morton. All stupid typos in first version fixed. Passes allmodconfig on i386, x86_64, alpha, arm as well as my usual config. Note #1: checking with sparse is still needed, because a driver can save and pass around flags or something. So far patch is very intrusive. Note #2: techically, we should break only if sizeof(flags) < sizeof(unsigned long), however, the more pain for getting suspicious code into kernel, the better. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Pass a lock expression to __cond_lock, like __acquire and __releaseJosh Triplett2006-09-291-5/+5
| | | | | | | | | | | Currently, __acquire and __release take a lock expression, but __cond_lock takes only a condition, not the lock acquired if the expression evaluates to true. Change __cond_lock to accept a lock expression, and change all the callers to pass in a lock expression. Signed-off-by: Josh Triplett <josh@freedesktop.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Replace _spin_trylock with spin_trylock in the IRQ variants to use ↵Josh Triplett2006-09-291-2/+2
| | | | | | | | | | | | | | __cond_lock spin_trylock_irq and spin_trylock_irqsave use _spin_trylock, which does not use the __cond_lock wrapper annotation and thus does not affect the lock context; change them to use spin_trylock instead, which does use __cond_lock. Signed-off-by: Josh Triplett <josh@freedesktop.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] lockdep: prove spinlock rwlock locking correctnessIngo Molnar2006-07-031-17/+46
| | | | | | | | | | Use the lock validator framework to prove spinlock and rwlock locking correctness. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Don't include linux/config.h from anywhere else in include/David Woodhouse2006-04-261-1/+0
| | | | Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* kbuild: set correct KBUILD_MODNAME when using well known kernel symbols as ↵Ustyugov Roman2005-12-261-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | module names This patch fixes a problem when we use well known kernel symbols as module names. For example, if module source name is current.c, idle_stack.c or etc., we have a bad KBUILD_MODNAME value. For example, KBUILD_MODNAME will be "get_current()" instead of "current", or "(init_thread_union.stack)" instead of "idle_task". The trick is to define a stringify macro on the commandline - named KBUILD_STR for namespace reasons - and then to stringify the module name. There are a few uses of KBUILD_MODNAME throughout the tree but the usage is for debug and will not be harmed by this change so left untouched for now. While at it KBUILD_BASENAME was changed too. Any spinlock usage in the unix module would have created wrong section names without it. Usage in spinlock.h fixed so it no longer stringify KBUILD_BASENAME. Original patch from Ustyogov Roman - all bugs introduced by me. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
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