Rafael, Locking doesn't seem safe in v8; I replied with my comments. I should be free this week to review the next round a little more quickly. Last week was hectic. Regards, Mike 2011/8/27 Rafael J. Wysocki <rjw@xxxxxxx>: > Mike, are patches [3-5/5] in this revision fine by you? > > Rafael > > > On Wednesday, August 24, 2011, MyungJoo Ham wrote: >> The patchset revision v8 has minor updates since v7 and v6. >> - Allow governors to have their own sysfs interface and init/exit callbacks. >> >> The patches 1/5 (OPP notifier) and 2/5 (DEVFREQ core) have no changes since v7. >> There has been reordering between "add common sysfs interfaces" patch >> and "add basic governors" (3/5 and 5/5) >> "add internal interfaces for governors (4/5)" patch has been newly >> introduced at v8 patchset. >> >> For a usage example, please look at >> http://git.infradead.org/users/kmpark/linux-2.6-samsung/shortlog/refs/heads/devfreq >> >> In the above git tree, DVFS (dynamic voltage and frequency scaling) mechanism >> is applied to the memory bus of Exynos4210 for Exynos4210-NURI boards. >> In the example, the LPDDR2 DRAM frequency changes between 133, 266, and 400MHz >> and other related clocks simply follow the determined DDR RAM clock. >> >> The DEVFREQ driver for Exynos4210 memory bus is at >> /drivers/devfreq/exynos4210_memorybus.c in the git tree. >> >> In the dd (writing and reading 360MiB) test with NURI board, the memory >> throughput was not changed (the performance is not deteriorated) while >> the SoC power consumption has been reduced by 1%. When the memory access >> is not that intense while the CPU is heavily used, the SoC power consumption >> has been reduced by 6%. The power consumption has been compared with the >> case using the conventional Exynos4210 CPUFREQ driver, which sets memory >> bus frequency according to the CPU core frequency. Besides, when the CPU core >> running slow and the memory access is intense, the performance (memory >> throughput) has been increased by 11% (with higher SoC power consumption of >> 5%). The tested governor is "simple-ondemand". >> >> MyungJoo Ham (5): >> PM / OPP: Add OPP availability change notifier. >> PM: Introduce DEVFREQ: generic DVFS framework with device-specific >> OPPs >> PM / DEVFREQ: add common sysfs interfaces >> PM / DEVFREQ: add internal interfaces for governors >> PM / DEVFREQ: add basic governors >> >> Documentation/ABI/testing/sysfs-devices-power | 46 +++ >> drivers/Kconfig | 2 + >> drivers/Makefile | 2 + >> drivers/base/power/opp.c | 29 ++ >> drivers/devfreq/Kconfig | 75 ++++ >> drivers/devfreq/Makefile | 5 + >> drivers/devfreq/devfreq.c | 463 +++++++++++++++++++++++++ >> drivers/devfreq/governor.h | 20 + >> drivers/devfreq/governor_performance.c | 24 ++ >> drivers/devfreq/governor_powersave.c | 24 ++ >> drivers/devfreq/governor_simpleondemand.c | 88 +++++ >> drivers/devfreq/governor_userspace.c | 119 +++++++ >> include/linux/devfreq.h | 150 ++++++++ >> include/linux/opp.h | 12 + >> 14 files changed, 1059 insertions(+), 0 deletions(-) >> create mode 100644 drivers/devfreq/Kconfig >> create mode 100644 drivers/devfreq/Makefile >> create mode 100644 drivers/devfreq/devfreq.c >> create mode 100644 drivers/devfreq/governor.h >> create mode 100644 drivers/devfreq/governor_performance.c >> create mode 100644 drivers/devfreq/governor_powersave.c >> create mode 100644 drivers/devfreq/governor_simpleondemand.c >> create mode 100644 drivers/devfreq/governor_userspace.c >> create mode 100644 include/linux/devfreq.h >> >> > > _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
