diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/tune.c | 1 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 29 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 1 |
3 files changed, 31 insertions, 0 deletions
diff --git a/kernel/sched/tune.c b/kernel/sched/tune.c index 68a24a044b0a..079b18802f17 100644 --- a/kernel/sched/tune.c +++ b/kernel/sched/tune.c @@ -725,6 +725,7 @@ schedtune_init_cgroups(void) for_each_possible_cpu(cpu) { bg = &per_cpu(cpu_boost_groups, cpu); memset(bg, 0, sizeof(struct boost_groups)); + raw_spin_lock_init(&bg->lock); } pr_info("schedtune: configured to support %d boost groups\n", diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 445601c580d6..ede4bf13d3e9 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -424,6 +424,35 @@ u64 ktime_get_raw_fast_ns(void) } EXPORT_SYMBOL_GPL(ktime_get_raw_fast_ns); +/** + * ktime_get_boot_fast_ns - NMI safe and fast access to boot clock. + * + * To keep it NMI safe since we're accessing from tracing, we're not using a + * separate timekeeper with updates to monotonic clock and boot offset + * protected with seqlocks. This has the following minor side effects: + * + * (1) Its possible that a timestamp be taken after the boot offset is updated + * but before the timekeeper is updated. If this happens, the new boot offset + * is added to the old timekeeping making the clock appear to update slightly + * earlier: + * CPU 0 CPU 1 + * timekeeping_inject_sleeptime64() + * __timekeeping_inject_sleeptime(tk, delta); + * timestamp(); + * timekeeping_update(tk, TK_CLEAR_NTP...); + * + * (2) On 32-bit systems, the 64-bit boot offset (tk->offs_boot) may be + * partially updated. Since the tk->offs_boot update is a rare event, this + * should be a rare occurrence which postprocessing should be able to handle. + */ +u64 notrace ktime_get_boot_fast_ns(void) +{ + struct timekeeper *tk = &tk_core.timekeeper; + + return (ktime_get_mono_fast_ns() + ktime_to_ns(tk->offs_boot)); +} +EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns); + /* Suspend-time cycles value for halted fast timekeeper. */ static cycle_t cycles_at_suspend; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index bff7d4c69274..293af3346c8c 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -890,6 +890,7 @@ static struct { { trace_clock, "perf", 1 }, { ktime_get_mono_fast_ns, "mono", 1 }, { ktime_get_raw_fast_ns, "mono_raw", 1 }, + { ktime_get_boot_fast_ns, "boot", 1 }, ARCH_TRACE_CLOCKS }; |