linux/kernel/softirq.c, branch v3.19

rcu: Remove "cpu" argument to rcu_note_context_switch()

2014-11-04T03:20:34Z

The "cpu" argument to rcu_note_context_switch() is always the current CPU, so drop it. This in turn allows the "cpu" argument to rcu_preempt_note_context_switch() to be removed, which allows the sole use of "cpu" in both functions to be replaced with a this_cpu_ptr(). Again, the anticipated cross-CPU uses of these functions has been replaced by NO_HZ_FULL. Signed-off-by: Paul E. McKenney Reviewed-by: Pranith Kumar

Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

2014-10-15T05:48:18Z

Pull percpu consistent-ops changes from Tejun Heo: "Way back, before the current percpu allocator was implemented, static and dynamic percpu memory areas were allocated and handled separately and had their own accessors. The distinction has been gone for many years now; however, the now duplicate two sets of accessors remained with the pointer based ones - this_cpu_*() - evolving various other operations over time. During the process, we also accumulated other inconsistent operations. This pull request contains Christoph's patches to clean up the duplicate accessor situation. __get_cpu_var() uses are replaced with with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr(). Unfortunately, the former sometimes is tricky thanks to C being a bit messy with the distinction between lvalues and pointers, which led to a rather ugly solution for cpumask_var_t involving the introduction of this_cpu_cpumask_var_ptr(). This converts most of the uses but not all. Christoph will follow up with the remaining conversions in this merge window and hopefully remove the obsolete accessors" * 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits) irqchip: Properly fetch the per cpu offset percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write. percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t Revert "powerpc: Replace __get_cpu_var uses" percpu: Remove __this_cpu_ptr clocksource: Replace __this_cpu_ptr with raw_cpu_ptr sparc: Replace __get_cpu_var uses avr32: Replace __get_cpu_var with __this_cpu_write blackfin: Replace __get_cpu_var uses tile: Use this_cpu_ptr() for hardware counters tile: Replace __get_cpu_var uses powerpc: Replace __get_cpu_var uses alpha: Replace __get_cpu_var ia64: Replace __get_cpu_var uses s390: cio driver &__get_cpu_var replacements s390: Replace __get_cpu_var uses mips: Replace __get_cpu_var uses MIPS: Replace __get_cpu_var uses in FPU emulator. arm: Replace __this_cpu_ptr with raw_cpu_ptr ...

rcu: Per-CPU operation cleanups to rcu_*_qs() functions

2014-09-07T23:27:35Z

The rcu_bh_qs(), rcu_preempt_qs(), and rcu_sched_qs() functions use old-style per-CPU variable access and write to ->passed_quiesce even if it is already set. This commit therefore updates to use the new-style per-CPU variable access functions and avoids the spurious writes. This commit also eliminates the "cpu" argument to these functions because they are always invoked on the indicated CPU. Reported-by: Peter Zijlstra Signed-off-by: Paul E. McKenney

time: Replace __get_cpu_var uses

2014-08-26T17:45:44Z

Convert uses of __get_cpu_var for creating a address from a percpu offset to this_cpu_ptr. The two cases where get_cpu_var is used to actually access a percpu variable are changed to use this_cpu_read/raw_cpu_read. Reviewed-by: Thomas Gleixner Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo

Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu

2014-05-22T09:36:10Z

Pull RCU updates from Paul E. McKenney: " 1. Update RCU documentation. These were posted to LKML at https://lkml.org/lkml/2014/4/28/634. 2. Miscellaneous fixes. These were posted to LKML at https://lkml.org/lkml/2014/4/28/645. 3. Torture-test changes. These were posted to LKML at https://lkml.org/lkml/2014/4/28/667. 4. Variable-name renaming cleanup, sent separately due to conflicts. This was posted to LKML at https://lkml.org/lkml/2014/5/13/854. 5. Patch to suppress RCU stall warnings while sysrq requests are being processed. This patch is the RCU portions of the patch that Rik posted to LKML at https://lkml.org/lkml/2014/4/29/457. The reason for pushing this patch ahead instead of waiting until 3.17 is that the NMI-based stack traces are messing up sysrq output, and in some cases also messing up the system as well." Signed-off-by: Ingo Molnar

asmlinkage: Add explicit __visible to drivers/, lib/, kernel/*

2014-05-05T23:07:46Z

As requested by Linus add explicit __visible to the asmlinkage users. This marks functions visible to assembler. Tree sweep for rest of tree. Signed-off-by: Andi Kleen Link: http://lkml.kernel.org/r/1398984278-29319-4-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin

softirq: A single rcu_bh_qs() call per softirq set is enough

2014-04-29T15:45:40Z

Calling rcu_bh_qs() after every softirq action is not really needed. What RCU needs is at least one rcu_bh_qs() per softirq round to note a quiescent state was passed for rcu_bh. Note for Paul and myself : this could be inlined as a single instruction and avoid smp_processor_id() (sone this_cpu_write(rcu_bh_data.passed_quiesce, 1)) Signed-off-by: Eric Dumazet Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett

genirq: x86: Ensure that dynamic irq allocation does not conflict

2014-04-28T10:20:00Z

On x86 the allocation of irq descriptors may allocate interrupts which are in the range of the GSI interrupts. That's wrong as those interrupts are hardwired and we don't have the irq domain translation like PPC. So one of these interrupts can be hooked up later to one of the devices which are hard wired to it and the io_apic init code for that particular interrupt line happily reuses that descriptor with a completely different configuration so hell breaks lose. Inside x86 we allocate dynamic interrupts from above nr_gsi_irqs, except for a few usage sites which have not yet blown up in our face for whatever reason. But for drivers which need an irq range, like the GPIO drivers, we have no limit in place and we don't want to expose such a detail to a driver. To cure this introduce a function which an architecture can implement to impose a lower bound on the dynamic interrupt allocations. Implement it for x86 and set the lower bound to nr_gsi_irqs, which is the end of the hardwired interrupt space, so all dynamic allocations happen above. That not only allows the GPIO driver to work sanely, it also protects the bogus callsites of create_irq_nr() in hpet, uv, irq_remapping and htirq code. They need to be cleaned up as well, but that's a separate issue. Reported-by: Jin Yao Signed-off-by: Thomas Gleixner Tested-by: Mika Westerberg Cc: Mathias Nyman Cc: Linus Torvalds Cc: Grant Likely Cc: H. Peter Anvin Cc: Rafael J. Wysocki Cc: Andy Shevchenko Cc: Krogerus Heikki Cc: Linus Walleij Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1404241617360.28206@ionos.tec.linutronix.de Signed-off-by: Thomas Gleixner

softirq: Add linux/irq.h to make it compile again

2014-03-19T10:28:14Z

On Sparc and S390 the removal of irq.h from kernel_stat.h causes: kernel/softirq.c:774:9: error: 'NR_IRQS_LEGACY' undeclared Reported-by: Peter Zijlstra Signed-off-by: Thomas Gleixner

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2014-01-31T17:02:51Z

Pull timer/dynticks updates from Ingo Molnar: "This tree contains misc dynticks updates: a fix and three cleanups" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/nohz: Fix overflow error in scheduler_tick_max_deferment() nohz_full: fix code style issue of tick_nohz_full_stop_tick nohz: Get timekeeping max deferment outside jiffies_lock tick: Rename tick_check_idle() to tick_irq_enter()