aboutsummaryrefslogtreecommitdiff
path: root/drivers/cpufreq/cpufreq_conservative.c
AgeCommit message (Collapse)Author
2006-03-26[PATCH] cpufreq_conservative: alternative initialise approachAlexander Clouter
Venki, author of cpufreq_ondemand, came up with a neater way to remove the initialiser code from the main loop of my code and out to the point when the governor is actually initialised. Not only does it look but it also feels cleaner, plus its simpler to understand. It also saves a bunch of pointless conditional statements in the main loop. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2006-03-26[PATCH] cpufreq_conservative: make for_each_cpu() safeAlexander Clouter
All these changes should make cpufreq_conservative safe in regards to the x86 for_each_cpu cpumask.h changes and whatnot. Whilst making it safe a number of pointless for loops related to the cpu mask's were removed. I was never comfortable with all those for loops, especially as the iteration is over the same data again and again for each CPU you had in a single poll, an O(n^2) outcome to frequency scaling. The approach I use is to assume by default no CPU's exist and it sets the requested_freq to zero as a kind of flag, the reasoning is in the source ;) If the CPU is queried and requested_freq is zero then it initialises the variable to current_freq and then continues as if nothing happened which should be the same net effect as before? Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2006-03-26[PATCH] cpufreq_conservative: alter default responsivenessAlexander Clouter
The sensible approach to making conservative less responsive than ondemand :) As mentioned in patch [1/4]. We do not want conservative to shoot through all the frequencies, its point (by default) is to slowly move through them. By default its ten times less responsive. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2006-03-26[PATCH] cpufreq_conservative: aligning of codebase with ondemandAlexander Clouter
Since the conservative govenor was released its codebase has drifted from the the direction and updates that have been applied to the ondemand govornor. This patch addresses the lack of updates in that period and brings conservative back up to date. The resulting diff file between cpufreq_ondemand.c and cpufreq_conservative.c is now much smaller and shows more clearly the differences between the two. Another reason to do this is ages ago, knowingly, I did a piss poor attempt at making conservative less responsive by knocking up DEF_SAMPLING_RATE_LATENCY_MULTIPLIER by two orders of magnitude. I did fix this ages ago but in my dis-organisation I must have toasted the diff and left it the way it was. About two weeks ago a user contacted me saying he was having problems with the conservative governor with his AMD Athlon XP-M 2800+ as /sys/devices/system/cpu/cpu0/cpufreq/conservative showed sampling_rate_min 9950000 sampling_rate_max 1360065408 Nine seconds to decide about changing the frequency....not too responsive :) Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2006-01-18[CPUFREQ] Convert drivers/cpufreq semaphores to mutexes.akpm@osdl.org
Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Dave Jones <davej@redhat.com>
2005-12-01[PATCH] cpufreq_conservative/ondemand: invert meaning of 'ignore nice'Alexander Clouter
The use of the 'ignore_nice' sysfs file is confusing to anyone using it. This removes the sysfs file 'ignore_nice' and in its place creates a 'ignore_nice_load' entry that defaults to '0'; meaning nice'd processes _are_ counted towards the 'business' calculation. WARNING: this obvious breaks any userland tools that expected ignore_nice' to exist, to draw attention to this fact it was concluded on the mailing list that the entry should be removed altogether so the userland app breaks and so the author can build simple to detect workaround. Having said that it seems currently very few tools even make use of this functionality; all I could find was a Gentoo Wiki entry. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Dave Jones <davej@redhat.com>
2005-10-27[PATCH] cpufreq: SMP fix for conservative governorDave Jones
Don't try to access not-present CPUs. Conservative governor will always oops on SMP without this fix. Fixes http://bugzilla.kernel.org/show_bug.cgi?id=4781 Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-31[CPUFREQ] ondemand,conservative governor idle_tick clean-upDave Jones
[PATCH] [3/5] ondemand,conservative governor idle_tick clean-up Ondemand and conservative governor clean-up, it factorises the idle ticks measurement. Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] ondemand,conservative governor store the idle ticks for all cpusDave Jones
[PATCH] [2/5] ondemand,conservative governor store the idle ticks for all cpus Ondemand, conservative governor did not store prev_cpu_idle_up into prev_cpu_idle_down for other CPUs than the current CPU. Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] ondemand,conservative minor bug-fix and cleanupDave Jones
[PATCH] [1/5] ondemand,conservative minor bug-fix and cleanup Attached patch fixes some minor issues with Alexander's patch and related cleanup in both ondemand and conservative governor. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] Conservative cpufreq governerDave Jones
A new cpufreq module, based on the ondemand one with my additional patches just posted. This one is more suitable for battery environments where its probably more appealing to have the cpu freq gracefully increase and decrease rather than flip between the min and max freq's. N.B. Bruno Ducrot pointed out that the amd64's "do have unacceptable latency between min and max freq transition, due to the step-by-step requirements (200MHz IIRC)"; so AMD64 users would probably benefit from this too. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>