Messages in this thread Patch in this message |  | | From | Chanwoo Choi <> | Subject | [PATCH 2/2] PM / devfreq: Add devfreq_transitions debugfs file | Date | Tue, 7 Jan 2020 18:05:19 +0900 |
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Add new devfreq_transitions debugfs file to track the frequency transitions of all devfreq devices for the simple profiling as following: - /sys/kernel/debug/devfreq/devfreq_transitions
And the user can decide the storage size (CONFIG_NR_DEVFREQ_TRANSITIONS) in Kconfig in order to save the transition history.
[Detailed description of each field of 'devfreq_transitions' debugfs file] - time_ms : Change time of frequency transition. (unit: millisecond) - dev_name : Device name of h/w. - dev : Device name made by devfreq core. - parent_dev : If devfreq device uses the passive governor, show parent devfreq device name. - load_% : If devfreq device uses the simple_ondemand governor, load is used by governor whene deciding the new frequency. (unit: percentage) - old_freq_hz : Frequency before changing. (unit: hz) - new_freq_hz : Frequency after changed. (unit: hz)
[For example on Exynos5422-based Odroid-XU3 board] $ cat /sys/kernel/debug/devfreq/devfreq_transitions time_ms dev_name dev parent_dev load_% old_freq_hz new_freq_hz ---------- ------------------------------ ---------- ---------- ---------- ------------ ------------ 14600 soc:bus_noc devfreq2 devfreq1 0 100000000 67000000 14600 soc:bus_fsys_apb devfreq3 devfreq1 0 200000000 100000000 14600 soc:bus_fsys devfreq4 devfreq1 0 200000000 100000000 14600 soc:bus_fsys2 devfreq5 devfreq1 0 150000000 75000000 14602 soc:bus_mfc devfreq6 devfreq1 0 222000000 96000000 14602 soc:bus_gen devfreq7 devfreq1 0 267000000 89000000 14602 soc:bus_g2d devfreq9 devfreq1 0 300000000 84000000 14602 soc:bus_g2d_acp devfreq10 devfreq1 0 267000000 67000000 14602 soc:bus_jpeg devfreq11 devfreq1 0 300000000 75000000 14602 soc:bus_jpeg_apb devfreq12 devfreq1 0 167000000 84000000 14603 soc:bus_disp1_fimd devfreq13 devfreq1 0 200000000 120000000 14603 soc:bus_disp1 devfreq14 devfreq1 0 300000000 120000000 14606 soc:bus_gscl_scaler devfreq15 devfreq1 0 300000000 150000000 14606 soc:bus_mscl devfreq16 devfreq1 0 333000000 84000000 14608 soc:bus_wcore devfreq1 9 333000000 84000000 14783 10c20000.memory-controller devfreq0 35 825000000 633000000 15873 soc:bus_wcore devfreq1 41 84000000 400000000 15873 soc:bus_noc devfreq2 devfreq1 0 67000000 100000000 [snip]
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> --- drivers/devfreq/Kconfig | 13 +++ drivers/devfreq/devfreq.c | 126 +++++++++++++++++++++++++++++ drivers/devfreq/governor.h | 3 + drivers/devfreq/governor_passive.c | 2 + include/linux/devfreq.h | 1 + 5 files changed, 145 insertions(+)
diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig index 0b1df12e0f21..84936eec0ef9 100644 --- a/drivers/devfreq/Kconfig +++ b/drivers/devfreq/Kconfig @@ -74,6 +74,19 @@ config DEVFREQ_GOV_PASSIVE through sysfs entries. The passive governor recommends that devfreq device uses the OPP table to get the frequency/voltage. +comment "DEVFREQ Debugging" + +config NR_DEVFREQ_TRANSITIONS + int "Maximum storage size to save DEVFREQ Transitions (10-1000)" + depends on DEBUG_FS + range 10 1000 + default "100" + help + Show the frequency transitions of all devfreq devices via + '/sys/kernel/debug/devfreq/devfreq_transitions' for the simple + profiling. It needs to decide the storage size to save transition + history of all devfreq devices. + comment "DEVFREQ Drivers" config ARM_EXYNOS_BUS_DEVFREQ diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index c7f5e4e06420..7abaae06fa65 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -268,6 +268,57 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) } EXPORT_SYMBOL(devfreq_update_status); +/** + * devfreq_update_transitions() - Update frequency transitions for debugfs file + * @devfreq: the devfreq instance + * @old_freq: the previous frequency before changing the frequency + * @new_freq: the new frequency after frequency is changed + */ +struct devfreq_transitions { + struct devfreq *devfreq; + struct devfreq_freqs freqs; + unsigned long load; +} debugfs_transitions[CONFIG_NR_DEVFREQ_TRANSITIONS]; + +static spinlock_t devfreq_debugfs_lock; +static int debugfs_transitions_index; + +void devfreq_update_transitions(struct devfreq *devfreq, + unsigned long old_freq, unsigned long new_freq, + unsigned long busy_time, unsigned long total_time) +{ + unsigned long load; + int i; + + if (!devfreq_debugfs || !devfreq || (old_freq == new_freq)) + return; + + spin_lock_nested(&devfreq_debugfs_lock, SINGLE_DEPTH_NESTING); + + i = debugfs_transitions_index; + + /* + * Calculate the load and if load is larger than 100, + * initialize to 100 because the unit of load is percentage. + */ + load = (total_time == 0 ? 0 : (100 * busy_time) / total_time); + if (load > 100) + load = 100; + + debugfs_transitions[i].devfreq = devfreq; + debugfs_transitions[i].freqs.time = ktime_to_ms(ktime_get()); + debugfs_transitions[i].freqs.old = old_freq; + debugfs_transitions[i].freqs.new = new_freq; + debugfs_transitions[i].load = load; + + if (++i == CONFIG_NR_DEVFREQ_TRANSITIONS) + i = 0; + debugfs_transitions_index = i; + + spin_unlock(&devfreq_debugfs_lock); +} +EXPORT_SYMBOL(devfreq_update_transitions); + /** * find_devfreq_governor() - Find devfreq governor from name * @name: name of the governor @@ -401,6 +452,10 @@ static int set_target(struct devfreq *devfreq, return err; } + devfreq_update_transitions(devfreq, cur_freq, new_freq, + devfreq->last_status.busy_time, + devfreq->last_status.total_time); + freqs.new = new_freq; notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); @@ -1787,6 +1842,72 @@ static int devfreq_summary_show(struct seq_file *s, void *data) } DEFINE_SHOW_ATTRIBUTE(devfreq_summary); +/** + * devfreq_transitions_show() - Show the frequency transitions of the registered + * devfreq devices via 'devfreq_transitions' debugfs file. + */ +static int devfreq_transitions_show(struct seq_file *s, void *data) +{ + struct devfreq *devfreq = NULL; + struct devfreq *p_devfreq = NULL; + struct devfreq_freqs *freqs = NULL; + unsigned long load; + int i = debugfs_transitions_index; + int count; + + seq_printf(s, "%-10s %-30s %-10s %-10s %-6s %-12s %-12s\n", + "time_ms", + "dev_name", + "dev", + "parent_dev", + "load_%", + "old_freq_hz", + "new_freq_hz"); + seq_printf(s, "%-10s %-30s %-10s %-10s %-6s %-12s %-12s\n", + "----------", + "------------------------------", + "----------", + "----------", + "----------", + "------------", + "------------"); + + spin_lock(&devfreq_debugfs_lock); + for (count = 0; count < CONFIG_NR_DEVFREQ_TRANSITIONS; count++) { + devfreq = debugfs_transitions[i].devfreq; + freqs = &debugfs_transitions[i].freqs; + load = debugfs_transitions[i].load; + + i = (CONFIG_NR_DEVFREQ_TRANSITIONS == ++i) ? 0 : i; + if (!devfreq) + continue; + +#if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE) + if (!strncmp(devfreq->governor_name, + DEVFREQ_GOV_PASSIVE, DEVFREQ_NAME_LEN)) { + struct devfreq_passive_data *data = devfreq->data; + + if (data) + p_devfreq = data->parent; + } else { + p_devfreq = NULL; + } +#endif + seq_printf(s, "%-10lld %-30s %-10s %-10s %-6ld %-12ld %-12ld\n", + freqs->time, + dev_name(devfreq->dev.parent), + dev_name(&devfreq->dev), + p_devfreq ? dev_name(&p_devfreq->dev) : "", + load, + freqs->old, + freqs->new); + } + spin_unlock(&devfreq_debugfs_lock); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(devfreq_transitions); + static int __init devfreq_init(void) { devfreq_class = class_create(THIS_MODULE, "devfreq"); @@ -1808,9 +1929,14 @@ static int __init devfreq_init(void) devfreq_debugfs = NULL; pr_warn("%s: couldn't create debugfs dir\n", __FILE__); } else { + spin_lock_init(&devfreq_debugfs_lock); + debugfs_create_file("devfreq_summary", 0444, devfreq_debugfs, NULL, &devfreq_summary_fops); + debugfs_create_file("devfreq_transitions", 0444, + devfreq_debugfs, NULL, + &devfreq_transitions_fops); } return 0; diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h index dc7533ccc3db..01eecfdaf2d6 100644 --- a/drivers/devfreq/governor.h +++ b/drivers/devfreq/governor.h @@ -68,6 +68,9 @@ extern int devfreq_add_governor(struct devfreq_governor *governor); extern int devfreq_remove_governor(struct devfreq_governor *governor); extern int devfreq_update_status(struct devfreq *devfreq, unsigned long freq); +extern void devfreq_update_transitions(struct devfreq *devfreq, + unsigned long old_freq, unsigned long new_freq, + unsigned long busy_time, unsigned long total_time); static inline int devfreq_update_stats(struct devfreq *df) { diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c index be6eeab9c814..05fa654239f5 100644 --- a/drivers/devfreq/governor_passive.c +++ b/drivers/devfreq/governor_passive.c @@ -109,6 +109,8 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq) if (ret < 0) goto out; + devfreq_update_transitions(devfreq, devfreq->previous_freq, freq, 0, 0); + if (devfreq->profile->freq_table && (devfreq_update_status(devfreq, freq))) dev_err(&devfreq->dev, diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 49cdb2378030..933692e5d867 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -196,6 +196,7 @@ struct devfreq { }; struct devfreq_freqs { + s64 time; unsigned long old; unsigned long new; }; -- 2.17.1
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