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| author | Joel Fernandes <joelagnelf@nvidia.com> | 2026-07-18 13:15:36 -0400 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2026-07-23 10:39:57 -0700 |
| commit | 34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch) | |
| tree | 7629759c1ec7148b95bc8ab3080df20a5ecd2273 /arch/arm/lib/delay.c | |
| download | linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip | |
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop. As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.
Add the missing accumulation so that the printed value reflects the
actual counts.
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'arch/arm/lib/delay.c')
| -rw-r--r-- | arch/arm/lib/delay.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/arm/lib/delay.c b/arch/arm/lib/delay.c new file mode 100644 index 000000000..b7fe84f68 --- /dev/null +++ b/arch/arm/lib/delay.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Delay loops based on the OpenRISC implementation. + * + * Copyright (C) 2012 ARM Limited + * + * Author: Will Deacon <will.deacon@arm.com> + */ + +#include <linux/clocksource.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/timex.h> + +/* + * Default to the loop-based delay implementation. + */ +struct arm_delay_ops arm_delay_ops __ro_after_init = { + .delay = __loop_delay, + .const_udelay = __loop_const_udelay, + .udelay = __loop_udelay, +}; + +static const struct delay_timer *delay_timer; +static bool delay_calibrated; +static u64 delay_res; + +int read_current_timer(unsigned long *timer_val) +{ + if (!delay_timer) + return -ENXIO; + + *timer_val = delay_timer->read_current_timer(); + return 0; +} +EXPORT_SYMBOL_GPL(read_current_timer); + +static inline u64 cyc_to_ns(u64 cyc, u32 mult, u32 shift) +{ + return (cyc * mult) >> shift; +} + +static void __timer_delay(unsigned long cycles) +{ + cycles_t start = get_cycles(); + + while ((get_cycles() - start) < cycles) + cpu_relax(); +} + +static void __timer_const_udelay(unsigned long xloops) +{ + unsigned long long loops = xloops; + loops *= arm_delay_ops.ticks_per_jiffy; + __timer_delay(loops >> UDELAY_SHIFT); +} + +static void __timer_udelay(unsigned long usecs) +{ + __timer_const_udelay(usecs * UDELAY_MULT); +} + +void __init register_current_timer_delay(const struct delay_timer *timer) +{ + u32 new_mult, new_shift; + u64 res; + + clocks_calc_mult_shift(&new_mult, &new_shift, timer->freq, + NSEC_PER_SEC, 3600); + res = cyc_to_ns(1ULL, new_mult, new_shift); + + if (res > 1000) { + pr_err("Ignoring delay timer %ps, which has insufficient resolution of %lluns\n", + timer, res); + return; + } + + if (!delay_calibrated && (!delay_res || (res < delay_res))) { + pr_info("Switching to timer-based delay loop, resolution %lluns\n", res); + delay_timer = timer; + lpj_fine = timer->freq / HZ; + delay_res = res; + + /* cpufreq may scale loops_per_jiffy, so keep a private copy */ + arm_delay_ops.ticks_per_jiffy = lpj_fine; + arm_delay_ops.delay = __timer_delay; + arm_delay_ops.const_udelay = __timer_const_udelay; + arm_delay_ops.udelay = __timer_udelay; + } else { + pr_info("Ignoring duplicate/late registration of read_current_timer delay\n"); + } +} + +unsigned long calibrate_delay_is_known(void) +{ + delay_calibrated = true; + return lpj_fine; +} + +void calibration_delay_done(void) +{ + delay_calibrated = true; +} |
