From 62663ea8220366472fe20462831f2d69d7987439 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Tue, 3 Feb 2009 17:46:46 +0100 Subject: ACPI: cpufreq: Remove deprecated /proc/acpi/processor/../performance proc entries They were long enough set deprecated... Update Documentation/cpu-freq/users-guide.txt: The deprecated files listed there seen not to exist for some time anymore already. Signed-off-by: Thomas Renninger Signed-off-by: Len Brown --- Documentation/cpu-freq/user-guide.txt | 16 ---------------- 1 file changed, 16 deletions(-) (limited to 'Documentation/cpu-freq/user-guide.txt') diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt index e3443ddcfb89..917918f84fc7 100644 --- a/Documentation/cpu-freq/user-guide.txt +++ b/Documentation/cpu-freq/user-guide.txt @@ -195,19 +195,3 @@ scaling_setspeed. By "echoing" a new frequency into this you can change the speed of the CPU, but only within the limits of scaling_min_freq and scaling_max_freq. - - -3.2 Deprecated Interfaces -------------------------- - -Depending on your kernel configuration, you might find the following -cpufreq-related files: -/proc/cpufreq -/proc/sys/cpu/*/speed -/proc/sys/cpu/*/speed-min -/proc/sys/cpu/*/speed-max - -These are files for deprecated interfaces to cpufreq, which offer far -less functionality. Because of this, these interfaces aren't described -here. - -- cgit v1.2.3 From ed12978453a3845c947695e7ad32bb3ede444813 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Wed, 4 Feb 2009 01:17:41 +0100 Subject: [CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency It's not only useful for the ondemand and conservative governors, but also for userspace daemons to know about the HW transition latency of the CPU. It is especially useful for userspace to know about this value when the ondemand or conservative governors are run. The sampling rate control value depends on it and for userspace being able to set sane tuning values there it has to know about the transition latency. Signed-off-by: Thomas Renninger Signed-off-by: Dave Jones --- Documentation/cpu-freq/user-guide.txt | 12 ++++++++++++ drivers/cpufreq/cpufreq.c | 3 +++ 2 files changed, 15 insertions(+) (limited to 'Documentation/cpu-freq/user-guide.txt') diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt index 917918f84fc7..75f41193f3e1 100644 --- a/Documentation/cpu-freq/user-guide.txt +++ b/Documentation/cpu-freq/user-guide.txt @@ -152,6 +152,18 @@ cpuinfo_min_freq : this file shows the minimum operating frequency the processor can run at(in kHz) cpuinfo_max_freq : this file shows the maximum operating frequency the processor can run at(in kHz) +cpuinfo_transition_latency The time it takes on this CPU to + switch between two frequencies in nano + seconds. If unknown or known to be + that high that the driver does not + work with the ondemand governor, -1 + (CPUFREQ_ETERNAL) will be returned. + Using this information can be useful + to choose an appropriate polling + frequency for a kernel governor or + userspace daemon. Make sure to not + switch the frequency too often + resulting in performance loss. scaling_driver : this file shows what cpufreq driver is used to set the frequency on this CPU diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 1867dac35aff..6fe466efb0b5 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -452,6 +452,7 @@ static ssize_t show_##file_name \ show_one(cpuinfo_min_freq, cpuinfo.min_freq); show_one(cpuinfo_max_freq, cpuinfo.max_freq); +show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); show_one(scaling_min_freq, min); show_one(scaling_max_freq, max); show_one(scaling_cur_freq, cur); @@ -659,6 +660,7 @@ __ATTR(_name, 0644, show_##_name, store_##_name) define_one_ro0400(cpuinfo_cur_freq); define_one_ro(cpuinfo_min_freq); define_one_ro(cpuinfo_max_freq); +define_one_ro(cpuinfo_transition_latency); define_one_ro(scaling_available_governors); define_one_ro(scaling_driver); define_one_ro(scaling_cur_freq); @@ -672,6 +674,7 @@ define_one_rw(scaling_setspeed); static struct attribute *default_attrs[] = { &cpuinfo_min_freq.attr, &cpuinfo_max_freq.attr, + &cpuinfo_transition_latency.attr, &scaling_min_freq.attr, &scaling_max_freq.attr, &affected_cpus.attr, -- cgit v1.2.3