linux/drivers/cpufreq
Viresh Kumar ab1b1c4e82 cpufreq: send new set of notification for transition failures
In the current code, if we fail during a frequency transition, we
simply send the POSTCHANGE notification with the old frequency. This
isn't enough.

One of the core users of these notifications is the code responsible
for keeping loops_per_jiffy aligned with frequency changes. And mostly
it is written as:

	if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
	    (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) {
		update-loops-per-jiffy...
	}

So, suppose we are changing to a higher frequency and failed during
transition, then following will happen:
- CPUFREQ_PRECHANGE notification with freq-new > freq-old
- CPUFREQ_POSTCHANGE notification with freq-new == freq-old

The first one will update loops_per_jiffy and second one will do
nothing. Even if we send the 2nd notification by exchanging values of
freq-new and old, some users of these notifications might get
unstable.

This can be fixed by simply calling cpufreq_notify_post_transition()
with error code and this routine will take care of sending
notifications in the correct order.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Folded 3 patches into one, rebased unicore2 changes]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-06 01:43:44 +01:00
..
acpi-cpufreq.c Merge branch 'pm-cpufreq' 2013-11-07 19:26:02 +01:00
amd_freq_sensitivity.c cpufreq: AMD "frequency sensitivity feedback" powersave bias for ondemand governor 2013-04-10 13:19:26 +02:00
arm_big_little_dt.c PM / OPP: rename header to linux/pm_opp.h 2013-10-25 22:33:23 +02:00
arm_big_little.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
arm_big_little.h cpufreq: arm_big_little: add in-kernel switching (IKS) support 2013-10-31 00:10:53 +01:00
at32ap-cpufreq.c cpufreq_ at32ap-cpufreq.c: Fix section mismatch 2013-12-10 08:46:38 +01:00
blackfin-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
cpufreq_conservative.c cpufreq: conservative: set requested_freq to policy max when it is over policy max 2013-11-12 23:18:20 +01:00
cpufreq_governor.c cpufreq: Fix timer/workqueue corruption by protecting reading governor_enabled 2014-01-06 01:22:02 +01:00
cpufreq_governor.h cpufreq: Fix timer/workqueue corruption by protecting reading governor_enabled 2014-01-06 01:22:02 +01:00
cpufreq_ondemand.c cpufreq: ondemand: Remove redundant return statement 2013-11-01 00:44:34 +01:00
cpufreq_performance.c cpufreq: Clean up header files included in the core 2013-08-07 23:34:09 +02:00
cpufreq_powersave.c cpufreq: Clean up header files included in the core 2013-08-07 23:34:09 +02:00
cpufreq_stats.c cpufreq: Fix wrong time unit conversion 2013-09-10 02:49:46 +02:00
cpufreq_userspace.c cpufreq / governor: Remove fossil comment 2013-10-17 23:00:20 +02:00
cpufreq-cpu0.c cpufreq: cpufreq-cpu0: clk_round_rate() can return a zero upon error 2013-12-06 23:19:19 +01:00
cpufreq-nforce2.c cpufreq: nforce2: don't initialize part of policy set by core 2013-10-16 00:50:29 +02:00
cpufreq.c cpufreq: send new set of notification for transition failures 2014-01-06 01:43:44 +01:00
cris-artpec3-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
cris-etraxfs-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
davinci-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
dbx500-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
e_powersaver.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
elanfreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
exynos4x12-cpufreq.c cpufreq: exynos: Remove unwanted EXPORT_SYMBOL 2013-11-20 23:55:38 +01:00
exynos4210-cpufreq.c cpufreq: exynos: Remove unwanted EXPORT_SYMBOL 2013-11-20 23:55:38 +01:00
exynos5250-cpufreq.c cpufreq: exynos5250: Set APLL rate using CCF API 2014-01-06 01:26:00 +01:00
exynos5440-cpufreq.c cpufreq: distinguish drivers that do asynchronous notifications 2013-10-31 00:11:08 +01:00
exynos-cpufreq.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-11-15 16:47:22 -08:00
exynos-cpufreq.h cpufreq: fix EXYNOS drivers selection 2013-08-12 12:00:21 +05:30
freq_table.c cpufreq: define generic .attr, .exit() and .verify() routines 2013-10-16 00:50:23 +02:00
gx-suspmod.c cpufreq: gx: don't initialize part of policy set by core 2013-10-16 00:50:30 +02:00
highbank-cpufreq.c cpufreq: highbank-cpufreq: Enable Midway/ECX-2000 2013-10-17 00:53:08 +02:00
ia64-acpi-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
imx6q-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
integrator-cpufreq.c ACPI and power management updates for 3.13-rc1 2013-11-14 13:41:48 +09:00
intel_pstate.c Merge back earlier 'pm-cpufreq' material. 2014-01-05 15:32:51 +01:00
Kconfig cpufreq: Select PM_OPP rather than depending on it 2013-12-22 22:03:49 +01:00
Kconfig.arm cpufreq: arm-big-little: Make driver dependent on CONFIG_BIG_LITTLE 2014-01-06 01:17:48 +01:00
Kconfig.powerpc cpufreq: remove CONFIG_CPU_FREQ_TABLE 2013-10-16 00:50:33 +02:00
Kconfig.x86 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-11-15 16:47:22 -08:00
kirkwood-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
longhaul.c cpufreq: Implement light weight ->target_index() routine 2013-10-25 22:42:24 +02:00
longhaul.h cpufreq: delete __cpuinit usage from all cpufreq files 2013-07-14 19:36:57 -04:00
longrun.c cpufreq: add new routine cpufreq_verify_within_cpu_limits() 2013-10-16 00:50:23 +02:00
loongson2_cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
Makefile cpufreq: arm_big_little: add vexpress SPC interface driver 2013-10-30 00:48:26 +01:00
maple-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
omap-cpufreq.c cpufreq: OMAP: Fix compilation error 'r & ret undeclared' 2013-11-14 00:52:48 +01:00
p4-clockmod.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
pasemi-cpufreq.c ACPI and power management updates for 3.13-rc1 2013-11-14 13:41:48 +09:00
pcc-cpufreq.c cpufreq: send new set of notification for transition failures 2014-01-06 01:43:44 +01:00
pmac32-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
pmac64-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
powernow-k6.c cpufreq: Implement light weight ->target_index() routine 2013-10-25 22:42:24 +02:00
powernow-k7.c cpufreq: Implement light weight ->target_index() routine 2013-10-25 22:42:24 +02:00
powernow-k7.h [CPUFREQ] Move x86 drivers to drivers/cpufreq/ 2011-05-19 18:51:07 -04:00
powernow-k8.c cpufreq: send new set of notification for transition failures 2014-01-06 01:43:44 +01:00
powernow-k8.h cpufreq: Remove support for hardware P-state chips from powernow-k8 2012-09-09 22:05:30 +02:00
ppc_cbe_cpufreq_pervasive.c cpufreq: powerpc/platforms/cell: move cpufreq driver to drivers/cpufreq 2013-04-10 13:19:26 +02:00
ppc_cbe_cpufreq_pmi.c cpufreq: powerpc/platforms/cell: move cpufreq driver to drivers/cpufreq 2013-04-10 13:19:26 +02:00
ppc_cbe_cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
ppc_cbe_cpufreq.h cpufreq: powerpc/platforms/cell: move cpufreq driver to drivers/cpufreq 2013-04-10 13:19:26 +02:00
ppc-corenet-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
pxa2xx-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
pxa3xx-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
s3c24xx-cpufreq-debugfs.c cpufreq: s3c24xx: move cpufreq driver to drivers/cpufreq 2013-05-20 23:04:28 +09:00
s3c24xx-cpufreq.c cpufreq: s3c24xx: Staticize local variable 2014-01-06 01:18:33 +01:00
s3c64xx-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
s3c2410-cpufreq.c cpufreq: s3c24xx: move cpufreq driver to drivers/cpufreq 2013-05-20 23:04:28 +09:00
s3c2412-cpufreq.c cpufreq: s3c24xx: move cpufreq driver to drivers/cpufreq 2013-05-20 23:04:28 +09:00
s3c2416-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
s3c2440-cpufreq.c cpufreq: s3c2440: Staticize local variables 2014-01-06 01:18:33 +01:00
s5pv210-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
sa1100-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
sa1110-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
sc520_freq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
sh-cpufreq.c cpufreq: sh: don't initialize part of policy set by core 2013-10-16 00:50:32 +02:00
sparc-us2e-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
sparc-us3-cpufreq.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
spear-cpufreq.c cpufreq: SPEAr: clk_round_rate() can return a zero upon error 2013-12-06 23:19:19 +01:00
speedstep-centrino.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
speedstep-ich.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
speedstep-lib.c cpufreq: Add support for x86 cpuinfo auto loading v4 2012-01-26 16:49:06 -08:00
speedstep-lib.h [CPUFREQ] Move x86 drivers to drivers/cpufreq/ 2011-05-19 18:51:07 -04:00
speedstep-smi.c cpufreq: move freq change notifications to cpufreq core 2013-10-31 00:11:08 +01:00
tegra-cpufreq.c cpufreq: tegra: don't error target() when suspended 2013-11-20 23:28:32 +01:00
unicore2-cpufreq.c cpufreq: send new set of notification for transition failures 2014-01-06 01:43:44 +01:00
vexpress-spc-cpufreq.c cpufreq: arm_big_little: add vexpress SPC interface driver 2013-10-30 00:48:26 +01:00