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@@ -42,61 +42,9 @@ ns2usecs(cycle_t nsec)
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return nsec;
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}
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-static const int time_sync_freq_max = 128;
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-static const cycle_t time_sync_thresh = 100000;
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-
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-static DEFINE_PER_CPU(cycle_t, time_offset);
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-static DEFINE_PER_CPU(cycle_t, prev_cpu_time);
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-static DEFINE_PER_CPU(int, time_sync_count);
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-static DEFINE_PER_CPU(int, time_sync_freq);
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-
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-/*
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- * Global lock which we take every now and then to synchronize
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- * the CPUs time. This method is not warp-safe, but it's good
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- * enough to synchronize slowly diverging time sources and thus
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- * it's good enough for tracing:
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- */
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-static DEFINE_SPINLOCK(time_sync_lock);
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-static cycle_t prev_global_time;
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-
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-static notrace cycle_t __ftrace_now_sync(cycles_t time, int cpu)
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-{
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- unsigned long flags;
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-
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- spin_lock_irqsave(&time_sync_lock, flags);
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-
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- /*
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- * Update the synchronization frequency:
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- */
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- if (per_cpu(time_sync_freq, cpu) < time_sync_freq_max)
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- per_cpu(time_sync_freq, cpu) *= 2;
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- per_cpu(time_sync_count, cpu) = per_cpu(time_sync_freq, cpu);
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-
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- if (time < prev_global_time) {
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- per_cpu(time_offset, cpu) += prev_global_time - time;
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- time = prev_global_time;
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- } else {
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- prev_global_time = time;
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- }
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-
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- spin_unlock_irqrestore(&time_sync_lock, flags);
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-
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- return time;
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-}
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-
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notrace cycle_t ftrace_now(int cpu)
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{
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- cycle_t prev_cpu_time, time, delta_time;
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-
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- prev_cpu_time = per_cpu(prev_cpu_time, cpu);
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- time = sched_clock() + per_cpu(time_offset, cpu);
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- delta_time = time-prev_cpu_time;
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-
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- if (unlikely(delta_time > time_sync_thresh ||
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- --per_cpu(time_sync_count, cpu) <= 0))
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- time = __ftrace_now_sync(time, cpu);
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-
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- return time;
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+ return cpu_clock(cpu);
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}
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static struct trace_array global_trace;
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