diff options
Diffstat (limited to 'src/sleep/battery-capacity.c')
| -rw-r--r-- | src/sleep/battery-capacity.c | 384 |
1 files changed, 384 insertions, 0 deletions
diff --git a/src/sleep/battery-capacity.c b/src/sleep/battery-capacity.c new file mode 100644 index 0000000..62a0746 --- /dev/null +++ b/src/sleep/battery-capacity.c @@ -0,0 +1,384 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include "sd-device.h" + +#include "battery-capacity.h" +#include "battery-util.h" +#include "device-private.h" +#include "device-util.h" +#include "extract-word.h" +#include "fd-util.h" +#include "fileio.h" +#include "hexdecoct.h" +#include "id128-util.h" +#include "parse-util.h" +#include "siphash24.h" + +#define DISCHARGE_RATE_FILEPATH "/var/lib/systemd/sleep/battery_discharge_percentage_rate_per_hour" +#define BATTERY_DISCHARGE_RATE_HASH_KEY SD_ID128_MAKE(5f,9a,20,18,38,76,46,07,8d,36,58,0b,bb,c4,e0,63) + +static void *CAPACITY_TO_PTR(int capacity) { + assert(capacity >= 0); + assert(capacity <= 100); + return INT_TO_PTR(capacity + 1); +} + +static int PTR_TO_CAPACITY(void *p) { + int capacity = PTR_TO_INT(p) - 1; + assert(capacity >= 0); + assert(capacity <= 100); + return capacity; +} + +static int siphash24_compress_device_sysattr( + sd_device *dev, + const char *attr, + struct siphash *state) { + + const char *x; + int r; + + assert(dev); + assert(attr); + assert(state); + + r = sd_device_get_sysattr_value(dev, attr, &x); + if (r < 0) + return log_device_debug_errno(dev, r, "Failed to read '%s' attribute: %m", attr); + + if (!isempty(x)) + siphash24_compress_string(x, state); + + return 0; +} + +static int siphash24_compress_id128( + int (*getter)(sd_id128_t *ret), + const char *name, + struct siphash *state) { + + sd_id128_t id; + int r; + + assert(getter); + assert(name); + assert(state); + + r = getter(&id); + if (r < 0) + return log_debug_errno(r, "Failed to get %s ID: %m", name); + + siphash24_compress(&id, sizeof(sd_id128_t), state); + return 0; +} + +/* Read system and battery identifier from specific location and generate hash of it */ +static uint64_t system_battery_identifier_hash(sd_device *dev) { + struct siphash state; + + assert(dev); + + siphash24_init(&state, BATTERY_DISCHARGE_RATE_HASH_KEY.bytes); + + (void) siphash24_compress_device_sysattr(dev, "manufacturer", &state); + (void) siphash24_compress_device_sysattr(dev, "model_name", &state); + (void) siphash24_compress_device_sysattr(dev, "serial_number", &state); + (void) siphash24_compress_id128(sd_id128_get_machine, "machine", &state); + (void) siphash24_compress_id128(id128_get_product, "product", &state); + + return siphash24_finalize(&state); +} + +/* Return success if battery percentage discharge rate per hour is in the range 1–199 */ +static bool battery_discharge_rate_is_valid(int battery_discharge_rate) { + return battery_discharge_rate > 0 && battery_discharge_rate < 200; +} + +/* Battery percentage discharge rate per hour is read from specific file. It is stored along with system + * and battery identifier hash to maintain the integrity of discharge rate value */ +static int get_battery_discharge_rate(sd_device *dev, int *ret) { + _cleanup_fclose_ FILE *f = NULL; + uint64_t current_hash_id; + const char *p; + int r; + + assert(dev); + assert(ret); + + f = fopen(DISCHARGE_RATE_FILEPATH, "re"); + if (!f) + return log_debug_errno(errno, "Failed to read discharge rate from " DISCHARGE_RATE_FILEPATH ": %m"); + + current_hash_id = system_battery_identifier_hash(dev); + + for (;;) { + _cleanup_free_ char *stored_hash_id = NULL, *stored_discharge_rate = NULL, *line = NULL; + uint64_t hash_id; + int discharge_rate; + + r = read_line(f, LONG_LINE_MAX, &line); + if (r < 0) + return log_debug_errno(r, "Failed to read discharge rate from " DISCHARGE_RATE_FILEPATH ": %m"); + if (r == 0) + break; + + p = line; + r = extract_many_words(&p, NULL, 0, &stored_hash_id, &stored_discharge_rate, NULL); + if (r < 0) + return log_debug_errno(r, "Failed to parse hash_id and discharge_rate read from " DISCHARGE_RATE_FILEPATH ": %m"); + if (r != 2) + return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Invalid number of items fetched from " DISCHARGE_RATE_FILEPATH); + + r = safe_atou64(stored_hash_id, &hash_id); + if (r < 0) + return log_debug_errno(r, "Failed to parse hash ID read from " DISCHARGE_RATE_FILEPATH " location: %m"); + + if (current_hash_id != hash_id) + /* matching device not found, move to next line */ + continue; + + r = safe_atoi(stored_discharge_rate, &discharge_rate); + if (r < 0) + return log_device_debug_errno(dev, r, "Failed to parse discharge rate read from " DISCHARGE_RATE_FILEPATH ": %m"); + + if (!battery_discharge_rate_is_valid(discharge_rate)) + return log_device_debug_errno(dev, SYNTHETIC_ERRNO(ERANGE), "Invalid battery discharge percentage rate per hour: %m"); + + *ret = discharge_rate; + return 0; /* matching device found, exit iteration */ + } + + return -ENOENT; +} + +/* Write battery percentage discharge rate per hour along with system and battery identifier hash to file */ +static int put_battery_discharge_rate(int estimated_battery_discharge_rate, uint64_t system_hash_id, bool trunc) { + int r; + + if (!battery_discharge_rate_is_valid(estimated_battery_discharge_rate)) + return log_debug_errno(SYNTHETIC_ERRNO(ERANGE), + "Invalid battery discharge rate %d%% per hour: %m", + estimated_battery_discharge_rate); + + r = write_string_filef( + DISCHARGE_RATE_FILEPATH, + WRITE_STRING_FILE_CREATE | WRITE_STRING_FILE_MKDIR_0755 | (trunc ? WRITE_STRING_FILE_TRUNCATE : 0), + "%"PRIu64" %d", + system_hash_id, + estimated_battery_discharge_rate); + if (r < 0) + return log_debug_errno(r, "Failed to update %s: %m", DISCHARGE_RATE_FILEPATH); + + log_debug("Estimated discharge rate %d%% per hour successfully saved to %s", estimated_battery_discharge_rate, DISCHARGE_RATE_FILEPATH); + + return 0; +} + +/* Store current capacity of each battery before suspension and timestamp */ +int fetch_batteries_capacity_by_name(Hashmap **ret) { + _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; + _cleanup_hashmap_free_ Hashmap *batteries_capacity_by_name = NULL; + int r; + + assert(ret); + + batteries_capacity_by_name = hashmap_new(&string_hash_ops_free); + if (!batteries_capacity_by_name) + return log_oom_debug(); + + r = battery_enumerator_new(&e); + if (r < 0) + return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); + + FOREACH_DEVICE(e, dev) { + _cleanup_free_ char *battery_name_copy = NULL; + const char *battery_name; + int battery_capacity; + + battery_capacity = r = battery_read_capacity_percentage(dev); + if (r < 0) + continue; + + r = sd_device_get_property_value(dev, "POWER_SUPPLY_NAME", &battery_name); + if (r < 0) { + log_device_debug_errno(dev, r, "Failed to get POWER_SUPPLY_NAME property, ignoring: %m"); + continue; + } + + battery_name_copy = strdup(battery_name); + if (!battery_name_copy) + return log_oom_debug(); + + r = hashmap_put(batteries_capacity_by_name, battery_name_copy, CAPACITY_TO_PTR(battery_capacity)); + if (r < 0) + return log_device_debug_errno(dev, r, "Failed to store battery capacity: %m"); + + TAKE_PTR(battery_name_copy); + } + + *ret = TAKE_PTR(batteries_capacity_by_name); + + return 0; +} + +int get_capacity_by_name(Hashmap *capacities_by_name, const char *name) { + void *p; + + assert(capacities_by_name); + assert(name); + + p = hashmap_get(capacities_by_name, name); + if (!p) + return -ENOENT; + + return PTR_TO_CAPACITY(p); +} + +/* Estimate battery discharge rate using stored previous and current capacity over timestamp difference */ +int estimate_battery_discharge_rate_per_hour( + Hashmap *last_capacity, + Hashmap *current_capacity, + usec_t before_timestamp, + usec_t after_timestamp) { + + _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; + bool trunc = true; + int r; + + assert(last_capacity); + assert(current_capacity); + assert(before_timestamp < after_timestamp); + + r = battery_enumerator_new(&e); + if (r < 0) + return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); + + FOREACH_DEVICE(e, dev) { + int battery_last_capacity, battery_current_capacity, battery_discharge_rate; + const char *battery_name; + uint64_t system_hash_id; + + r = sd_device_get_property_value(dev, "POWER_SUPPLY_NAME", &battery_name); + if (r < 0) { + log_device_debug_errno(dev, r, "Failed to read battery name, ignoring: %m"); + continue; + } + + battery_last_capacity = get_capacity_by_name(last_capacity, battery_name); + if (battery_last_capacity < 0) + continue; + + battery_current_capacity = get_capacity_by_name(current_capacity, battery_name); + if (battery_current_capacity < 0) + continue; + + if (battery_current_capacity >= battery_last_capacity) { + log_device_debug(dev, "Battery was not discharged during suspension"); + continue; + } + + system_hash_id = system_battery_identifier_hash(dev); + + log_device_debug(dev, + "%d%% was discharged in %s. Estimating discharge rate...", + battery_last_capacity - battery_current_capacity, + FORMAT_TIMESPAN(after_timestamp - before_timestamp, USEC_PER_SEC)); + + battery_discharge_rate = (battery_last_capacity - battery_current_capacity) * USEC_PER_HOUR / (after_timestamp - before_timestamp); + r = put_battery_discharge_rate(battery_discharge_rate, system_hash_id, trunc); + if (r < 0) + log_device_warning_errno(dev, r, "Failed to update battery discharge rate, ignoring: %m"); + else + trunc = false; + } + + return 0; +} + +/* Calculate the suspend interval for each battery and then return their sum */ +int get_total_suspend_interval(Hashmap *last_capacity, usec_t *ret) { + _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; + usec_t total_suspend_interval = 0; + int r; + + assert(last_capacity); + assert(ret); + + r = battery_enumerator_new(&e); + if (r < 0) + return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); + + FOREACH_DEVICE(e, dev) { + int battery_last_capacity, previous_discharge_rate = 0; + const char *battery_name; + usec_t suspend_interval; + + r = sd_device_get_property_value(dev, "POWER_SUPPLY_NAME", &battery_name); + if (r < 0) { + log_device_debug_errno(dev, r, "Failed to read battery name, ignoring: %m"); + continue; + } + + battery_last_capacity = get_capacity_by_name(last_capacity, battery_name); + if (battery_last_capacity <= 0) + continue; + + r = get_battery_discharge_rate(dev, &previous_discharge_rate); + if (r < 0) { + log_device_debug_errno(dev, r, "Failed to get discharge rate, ignoring: %m"); + continue; + } + + if (previous_discharge_rate == 0) + continue; + + if (battery_last_capacity * 2 <= previous_discharge_rate) { + log_device_debug(dev, "Current battery capacity percentage too low compared to discharge rate"); + continue; + } + suspend_interval = battery_last_capacity * USEC_PER_HOUR / previous_discharge_rate; + + total_suspend_interval = usec_add(total_suspend_interval, suspend_interval); + } + /* Previous discharge rate is stored in per hour basis converted to usec. + * Subtract 30 minutes from the result to keep a buffer of 30 minutes before battery gets critical */ + total_suspend_interval = usec_sub_unsigned(total_suspend_interval, 30 * USEC_PER_MINUTE); + if (total_suspend_interval == 0) + return -ENOENT; + + *ret = total_suspend_interval; + + return 0; +} + +/* Return true if all batteries have acpi_btp support */ +int battery_trip_point_alarm_exists(void) { + _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; + bool has_battery = false; + int r; + + r = battery_enumerator_new(&e); + if (r < 0) + return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); + + FOREACH_DEVICE(e, dev) { + const char *alarm_attr; + int has_alarm; + + has_battery = true; + + r = sd_device_get_sysattr_value(dev, "alarm", &alarm_attr); + if (r < 0) + return log_device_debug_errno(dev, r, "Failed to read battery alarm attribute: %m"); + + r = safe_atoi(alarm_attr, &has_alarm); + if (r < 0) + return log_device_debug_errno(dev, r, + "Failed to parse battery alarm attribute '%s': %m", + alarm_attr); + if (has_alarm <= 0) + return false; + } + + return has_battery; +} |