diff --git a/Documentation/scheduler/sched-pelt.c b/Documentation/scheduler/sched-pelt.c index e4219139386a..cd3e1fe7a98a 100644 --- a/Documentation/scheduler/sched-pelt.c +++ b/Documentation/scheduler/sched-pelt.c @@ -10,21 +10,21 @@ #include #include -#define HALFLIFE 32 +#define HALFLIFE { 32, 16, 8 } #define SHIFT 32 double y; -void calc_runnable_avg_yN_inv(void) +void calc_runnable_avg_yN_inv(const int halflife) { int i; unsigned int x; printf("static const u32 runnable_avg_yN_inv[] = {"); - for (i = 0; i < HALFLIFE; i++) { + for (i = 0; i < halflife; i++) { x = ((1UL<<32)-1)*pow(y, i); - if (i % 6 == 0) printf("\n\t"); + if (i % 4 == 0) printf("\n\t"); printf("0x%8x, ", x); } printf("\n};\n\n"); @@ -32,12 +32,12 @@ void calc_runnable_avg_yN_inv(void) int sum = 1024; -void calc_runnable_avg_yN_sum(void) +void calc_runnable_avg_yN_sum(const int halflife) { int i; printf("static const u32 runnable_avg_yN_sum[] = {\n\t 0,"); - for (i = 1; i <= HALFLIFE; i++) { + for (i = 1; i <= halflife; i++) { if (i == 1) sum *= y; else @@ -55,7 +55,7 @@ int n = -1; /* first period */ long max = 1024; -void calc_converged_max(void) +void calc_converged_max(const int halflife) { long last = 0, y_inv = ((1UL<<32)-1)*y; @@ -73,17 +73,17 @@ void calc_converged_max(void) last = max; } n--; - printf("#define LOAD_AVG_PERIOD %d\n", HALFLIFE); + printf("#define LOAD_AVG_PERIOD %d\n", halflife); printf("#define LOAD_AVG_MAX %ld\n", max); -// printf("#define LOAD_AVG_MAX_N %d\n\n", n); + printf("#define LOAD_AVG_MAX_N %d\n\n", n); } -void calc_accumulated_sum_32(void) +void calc_accumulated_sum_32(const int halflife) { int i, x = sum; printf("static const u32 __accumulated_sum_N32[] = {\n\t 0,"); - for (i = 1; i <= n/HALFLIFE+1; i++) { + for (i = 1; i <= n/halflife+1; i++) { if (i > 1) x = x/2 + sum; @@ -97,12 +97,22 @@ void calc_accumulated_sum_32(void) void main(void) { + int hl_value[] = HALFLIFE; + int hl_count = sizeof(hl_value) / sizeof(int); + int hl_idx, halflife; + printf("/* Generated by Documentation/scheduler/sched-pelt; do not modify. */\n\n"); - y = pow(0.5, 1/(double)HALFLIFE); + for (hl_idx = 0; hl_idx < hl_count; ++hl_idx) { + halflife = hl_value[hl_idx]; + + y = pow(0.5, 1/(double)halflife); - calc_runnable_avg_yN_inv(); -// calc_runnable_avg_yN_sum(); - calc_converged_max(); -// calc_accumulated_sum_32(); + printf("#if CONFIG_PELT_UTIL_HALFLIFE_%d\n", halflife); + calc_runnable_avg_yN_inv(halflife); + calc_runnable_avg_yN_sum(halflife); + calc_converged_max(halflife); + calc_accumulated_sum_32(halflife); + printf("#endif\n\n"); + } } diff --git a/init/Kconfig b/init/Kconfig index a900301d2bc9..7ff9d2ab3b8d 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -610,6 +610,41 @@ config HAVE_UNSTABLE_SCHED_CLOCK config GENERIC_SCHED_CLOCK bool +menu "FAIR Scheuler tunables" + +choice + prompt "Utilization's PELT half-Life" + default PELT_UTIL_HALFLIFE_32 + help + Allows choosing one of the possible values for the PELT half-life to + be used for the update of the utilization of tasks and CPUs. + The half-life is the amount of [ms] required by the PELT signal to + build up to 50% utilization. The higher the half-life the longer it + takes for a task to be represented as a big one. + + If not sure, use the default of 32 ms. + +config PELT_UTIL_HALFLIFE_32 + bool "32 ms, default for server" + +config PELT_UTIL_HALFLIFE_16 + bool "16 ms, suggested for interactive workloads" + help + Use 16ms as PELT half-life value. This will increase the ramp-up and + decay of utlization and load twice as fast as for the default + configuration using 32ms. + +config PELT_UTIL_HALFLIFE_8 + bool "8 ms, very fast" + help + Use 8ms as PELT half-life value. This will increase the ramp-up and + decay of utlization and load four time as fast as for the default + configuration using 32ms. + +endchoice + +endmenu # FAIR Scheduler tunables" + # # For architectures that want to enable the support for NUMA-affine scheduler # balancing logic: diff --git a/kernel/sched/sched-pelt.h b/kernel/sched/sched-pelt.h index a26473674fb7..ac7d489be8ce 100644 --- a/kernel/sched/sched-pelt.h +++ b/kernel/sched/sched-pelt.h @@ -1,14 +1,62 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* Generated by Documentation/scheduler/sched-pelt; do not modify. */ + +#ifdef CONFIG_PELT_UTIL_HALFLIFE_32 static const u32 runnable_avg_yN_inv[] = { - 0xffffffff, 0xfa83b2da, 0xf5257d14, 0xefe4b99a, 0xeac0c6e6, 0xe5b906e6, - 0xe0ccdeeb, 0xdbfbb796, 0xd744fcc9, 0xd2a81d91, 0xce248c14, 0xc9b9bd85, - 0xc5672a10, 0xc12c4cc9, 0xbd08a39e, 0xb8fbaf46, 0xb504f333, 0xb123f581, - 0xad583ee9, 0xa9a15ab4, 0xa5fed6a9, 0xa2704302, 0x9ef5325f, 0x9b8d39b9, - 0x9837f050, 0x94f4efa8, 0x91c3d373, 0x8ea4398a, 0x8b95c1e3, 0x88980e80, - 0x85aac367, 0x82cd8698, + 0xffffffff,0xfa83b2da,0xf5257d14,0xefe4b99a, + 0xeac0c6e6,0xe5b906e6,0xe0ccdeeb,0xdbfbb796, + 0xd744fcc9,0xd2a81d91,0xce248c14,0xc9b9bd85, + 0xc5672a10,0xc12c4cc9,0xbd08a39e,0xb8fbaf46, + 0xb504f333,0xb123f581,0xad583ee9,0xa9a15ab4, + 0xa5fed6a9,0xa2704302,0x9ef5325f,0x9b8d39b9, + 0x9837f050,0x94f4efa8,0x91c3d373,0x8ea4398a, + 0x8b95c1e3,0x88980e80,0x85aac367,0x82cd8698, +}; + +static const u32 runnable_avg_yN_sum[] = { + 0, 1002, 1982, 2941, 3880, 4798, 5697, 6576, 7437, 8279, 9103, + 9909,10698,11470,12226,12966,13690,14398,15091,15769,16433,17082, + 17718,18340,18949,19545,20128,20698,21256,21802,22336,22859,23371, }; #define LOAD_AVG_PERIOD 32 #define LOAD_AVG_MAX 47742 +#define LOAD_AVG_MAX_N 345 + +#endif + +#ifdef CONFIG_PELT_UTIL_HALFLIFE_16 +static const u32 runnable_avg_yN_inv[] = { + 0xffffffff,0xf5257d14,0xeac0c6e6,0xe0ccdeeb, + 0xd744fcc9,0xce248c14,0xc5672a10,0xbd08a39e, + 0xb504f333,0xad583ee9,0xa5fed6a9,0x9ef5325f, + 0x9837f050,0x91c3d373,0x8b95c1e3,0x85aac367, +}; + +static const u32 runnable_avg_yN_sum[] = { + 0,22380,22411,22441,22470,22497,22523,22548,22572,22595,22617, + 22638,22658,22677,22696,22714,22731, +}; + +#define LOAD_AVG_PERIOD 16 +#define LOAD_AVG_MAX 24152 +#define LOAD_AVG_MAX_N 517 + +#endif + +#ifdef CONFIG_PELT_UTIL_HALFLIFE_8 +static const u32 runnable_avg_yN_inv[] = { + 0xffffffff,0xeac0c6e6,0xd744fcc9,0xc5672a10, + 0xb504f333,0xa5fed6a9,0x9837f050,0x8b95c1e3, +}; + +static const u32 runnable_avg_yN_sum[] = { + 0,20844,20053,19327,18661,18051,17491,16978,16507, +}; + +#define LOAD_AVG_PERIOD 8 +#define LOAD_AVG_MAX 12337 +#define LOAD_AVG_MAX_N 603 + +#endif