From 1f81c5efc020314b2db30d77efe228b7e117750d Mon Sep 17 00:00:00 2001 From: Len Brown Date: Thu, 19 Mar 2020 18:26:05 -0400 Subject: [PATCH] tools/power turbostat: Fix missing SYS_LPI counter on some Chromebooks Some Chromebook BIOS' do not export an ACPI LPIT, which is how Linux finds the residency counter for CPU and SYSTEM low power states, that is exports in /sys/devices/system/cpu/cpuidle/*residency_us When these sysfs attributes are missing, check the debugfs attrubte from the pmc_core driver, which accesses the same counter value. Signed-off-by: Len Brown --- tools/power/x86/turbostat/turbostat.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index 761146c4f9bc..3ecbf709a48c 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -304,6 +304,10 @@ int *irqs_per_cpu; /* indexed by cpu_num */ void setup_all_buffers(void); +char *sys_lpi_file; +char *sys_lpi_file_sysfs = "/sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us"; +char *sys_lpi_file_debugfs = "/sys/kernel/debug/pmc_core/slp_s0_residency_usec"; + int cpu_is_not_present(int cpu) { return !CPU_ISSET_S(cpu, cpu_present_setsize, cpu_present_set); @@ -2916,8 +2920,6 @@ int snapshot_gfx_mhz(void) * * record snapshot of * /sys/devices/system/cpu/cpuidle/low_power_idle_cpu_residency_us - * - * return 1 if config change requires a restart, else return 0 */ int snapshot_cpu_lpi_us(void) { @@ -2941,17 +2943,14 @@ int snapshot_cpu_lpi_us(void) /* * snapshot_sys_lpi() * - * record snapshot of - * /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us - * - * return 1 if config change requires a restart, else return 0 + * record snapshot of sys_lpi_file */ int snapshot_sys_lpi_us(void) { FILE *fp; int retval; - fp = fopen_or_die("/sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us", "r"); + fp = fopen_or_die(sys_lpi_file, "r"); retval = fscanf(fp, "%lld", &cpuidle_cur_sys_lpi_us); if (retval != 1) { @@ -4946,10 +4945,16 @@ void process_cpuid() else BIC_NOT_PRESENT(BIC_CPU_LPI); - if (!access("/sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us", R_OK)) + if (!access(sys_lpi_file_sysfs, R_OK)) { + sys_lpi_file = sys_lpi_file_sysfs; BIC_PRESENT(BIC_SYS_LPI); - else + } else if (!access(sys_lpi_file_debugfs, R_OK)) { + sys_lpi_file = sys_lpi_file_debugfs; + BIC_PRESENT(BIC_SYS_LPI); + } else { + sys_lpi_file_sysfs = NULL; BIC_NOT_PRESENT(BIC_SYS_LPI); + } if (!quiet) decode_misc_feature_control();