/* * Uniprocessor-only support functions. The counterpart to kernel/smp.c */ #include #include #include #include #include int smp_call_function_single(int cpu, void (*func) (void *info), void *info, int wait) { unsigned long flags; WARN_ON(cpu != 0); local_irq_save(flags); func(info); local_irq_restore(flags); return 0; } EXPORT_SYMBOL(smp_call_function_single); int smp_call_function_single_async(int cpu, struct call_single_data *csd) { unsigned long flags; local_irq_save(flags); csd->func(csd->info); local_irq_restore(flags); return 0; } EXPORT_SYMBOL(smp_call_function_single_async); int on_each_cpu(smp_call_func_t func, void *info, int wait) { unsigned long flags; local_irq_save(flags); func(info); local_irq_restore(flags); return 0; } EXPORT_SYMBOL(on_each_cpu); /* * Note we still need to test the mask even for UP * because we actually can get an empty mask from * code that on SMP might call us without the local * CPU in the mask. */ void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func, void *info, bool wait) { unsigned long flags; if (cpumask_test_cpu(0, mask)) { local_irq_save(flags); func(info); local_irq_restore(flags); } } EXPORT_SYMBOL(on_each_cpu_mask); /* * Preemption is disabled here to make sure the cond_func is called under the * same condtions in UP and SMP. */ void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), smp_call_func_t func, void *info, bool wait, gfp_t gfp_flags) { unsigned long flags; preempt_disable(); if (cond_func(0, info)) { local_irq_save(flags); func(info); local_irq_restore(flags); } preempt_enable(); } EXPORT_SYMBOL(on_each_cpu_cond); int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys) { int ret; if (cpu != 0) return -ENXIO; if (phys) hypervisor_pin_vcpu(0); ret = func(par); if (phys) hypervisor_pin_vcpu(-1); return ret; } EXPORT_SYMBOL_GPL(smp_call_on_cpu); .cgi/linux/net-next.git/diff/net/core/netprio_cgroup.c?id=dd86e373e09fb16b83e8adf5c48c421a4ca76468'>diff
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authorThomas Gleixner <tglx@linutronix.de>2017-01-31 23:58:38 +0100
committerIngo Molnar <mingo@kernel.org>2017-02-01 08:37:27 +0100
commitdd86e373e09fb16b83e8adf5c48c421a4ca76468 (patch)
tree55703c2ea8584e303e342090614e0aab3509ab21 /net/core/netprio_cgroup.c
parent0b3589be9b98994ce3d5aeca52445d1f5627c4ba (diff)
perf/x86/intel/rapl: Make package handling more robust
The package management code in RAPL relies on package mapping being available before a CPU is started. This changed with: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") because the ACPI/BIOS information turned out to be unreliable, but that left RAPL in broken state. This was not noticed because on a regular boot all CPUs are online before RAPL is initialized. A possible fix would be to reintroduce the mess which allocates a package data structure in CPU prepare and when it turns out to already exist in starting throw it away later in the CPU online callback. But that's a horrible hack and not required at all because RAPL becomes functional for perf only in the CPU online callback. That's correct because user space is not yet informed about the CPU being onlined, so nothing caan rely on RAPL being available on that particular CPU. Move the allocation to the CPU online callback and simplify the hotplug handling. At this point the package mapping is established and correct. This also adds a missing check for available package data in the event_init() function. Reported-by: Yasuaki Ishimatsu <yasu.isimatu@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") Link: http://lkml.kernel.org/r/20170131230141.212593966@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/core/netprio_cgroup.c')