From 3de04f9cecf0d50e895f9fe0164ecbbbae997319 Mon Sep 17 00:00:00 2001 From: Drew Richardson Date: Thu, 1 Mar 2012 12:00:00 -0800 Subject: gator: Version 5.9 Signed-off-by: Drew Richardson --- driver/gator_hrtimer_perf.c | 113 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 113 insertions(+) create mode 100644 driver/gator_hrtimer_perf.c (limited to 'driver/gator_hrtimer_perf.c') diff --git a/driver/gator_hrtimer_perf.c b/driver/gator_hrtimer_perf.c new file mode 100644 index 0000000..7c0333f --- /dev/null +++ b/driver/gator_hrtimer_perf.c @@ -0,0 +1,113 @@ +/** + * Copyright (C) ARM Limited 2011-2012. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +// gator_hrtimer_gator.c is used if perf is not supported +// update, gator_hrtimer_gator.c always used until issues resolved with perf hrtimers +#if 0 + +// Note: perf Cortex support added in 2.6.35 and PERF_COUNT_SW_CPU_CLOCK/hrtimer broken on 2.6.35 and 2.6.36 +// not relevant as this code is not active until 3.0.0, but wanted to document the issue + +void (*callback)(void); +static int profiling_interval; +static DEFINE_PER_CPU(struct perf_event *, perf_hrtimer); +static DEFINE_PER_CPU(struct perf_event_attr *, perf_hrtimer_attr); + +static void gator_hrtimer_shutdown(void); + +#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 1, 0) +static void hrtimer_overflow_handler(struct perf_event *event, int unused, struct perf_sample_data *data, struct pt_regs *regs) +#else +static void hrtimer_overflow_handler(struct perf_event *event, struct perf_sample_data *data, struct pt_regs *regs) +#endif +{ + (*callback)(); +} + +static int gator_online_single_hrtimer(int cpu) +{ + if (per_cpu(perf_hrtimer, cpu) != 0 || per_cpu(perf_hrtimer_attr, cpu) == 0) + return 0; + +#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 1, 0) + per_cpu(perf_hrtimer, cpu) = perf_event_create_kernel_counter(per_cpu(perf_hrtimer_attr, cpu), cpu, 0, hrtimer_overflow_handler); +#else + per_cpu(perf_hrtimer, cpu) = perf_event_create_kernel_counter(per_cpu(perf_hrtimer_attr, cpu), cpu, 0, hrtimer_overflow_handler, 0); +#endif + if (IS_ERR(per_cpu(perf_hrtimer, cpu))) { + per_cpu(perf_hrtimer, cpu) = NULL; + return -1; + } + + if (per_cpu(perf_hrtimer, cpu)->state != PERF_EVENT_STATE_ACTIVE) { + perf_event_release_kernel(per_cpu(perf_hrtimer, cpu)); + per_cpu(perf_hrtimer, cpu) = NULL; + return -1; + } + + return 0; +} + +static void gator_hrtimer_online(int cpu) +{ + if (gator_online_single_hrtimer(cpu) < 0) { + pr_debug("gator: unable to online the hrtimer on cpu%d\n", cpu); + } +} + +static void gator_hrtimer_offline(int cpu) +{ + if (per_cpu(perf_hrtimer, cpu)) { + perf_event_release_kernel(per_cpu(perf_hrtimer, cpu)); + per_cpu(perf_hrtimer, cpu) = NULL; + } +} + +static int gator_hrtimer_init(int interval, void (*func)(void)) +{ + u32 size = sizeof(struct perf_event_attr); + int cpu; + + callback = func; + + // calculate profiling interval + profiling_interval = 1000000000 / interval; + + for_each_present_cpu(cpu) { + per_cpu(perf_hrtimer, cpu) = 0; + per_cpu(perf_hrtimer_attr, cpu) = kmalloc(size, GFP_KERNEL); + if (per_cpu(perf_hrtimer_attr, cpu) == 0) { + gator_hrtimer_shutdown(); + return -1; + } + + memset(per_cpu(perf_hrtimer_attr, cpu), 0, size); + per_cpu(perf_hrtimer_attr, cpu)->type = PERF_TYPE_SOFTWARE; + per_cpu(perf_hrtimer_attr, cpu)->size = size; + per_cpu(perf_hrtimer_attr, cpu)->config = PERF_COUNT_SW_CPU_CLOCK; + per_cpu(perf_hrtimer_attr, cpu)->sample_period = profiling_interval; + per_cpu(perf_hrtimer_attr, cpu)->pinned = 1; + } + + return 0; +} + +static void gator_hrtimer_shutdown(void) +{ + int cpu; + + for_each_present_cpu(cpu) { + if (per_cpu(perf_hrtimer_attr, cpu)) { + kfree(per_cpu(perf_hrtimer_attr, cpu)); + per_cpu(perf_hrtimer_attr, cpu) = NULL; + } + } +} + +#endif -- cgit v1.2.3