https://bugzilla.kernel.org/show_bug.cgi?id=64271 Bug ID: 64271 Summary: Intel Pstate driver - "kick" code is not needed Product: Power Management Version: 2.5 Kernel Version: 3.12rc7 Hardware: All OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: cpufreq Assignee: cpufreq@xxxxxxxxxxxxxxx Reporter: dsmythies@xxxxxxxxx Regression: No There is code in the routine intel_pstate_timer_func to "kick" the CPU out of the minimum pstate. The code was added back when several things were not working properly with the driver. It was added due to a "ping-pong" issue uncovered by the Phoronix test suite ffpmeg test. I have tried extensively to recreate the issue with the "kick" code removed and have not been able to. I am unable to detect any difference with the ffmpeg test between the normal code and code with the "kick removed" The assertion is that the "kick" code is not required and should be deleted. This bug has been extracted from bug 59481 which ended up discussing a few tangent issues. The main issue was solved and the bug closed. Now I am following up on some of the tangent issues. I am saying the kick portion of this code can be removed because it serves no purpose and makes the code harder to read and understand: static void intel_pstate_timer_func(unsigned long __data) { struct cpudata *cpu = (struct cpudata *) __data; intel_pstate_sample(cpu); intel_pstate_adjust_busy_pstate(cpu); if (cpu->pstate.current_pstate == cpu->pstate.min_pstate) { cpu->min_pstate_count++; if (!(cpu->min_pstate_count % 5)) { intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate); } } else cpu->min_pstate_count = 0; intel_pstate_set_sample_time(cpu); } Where this was left on 2013.07.18 with Dirk Brandewie was that he wanted to go back and verify in his test environment. Which, of course, should be done. -- You are receiving this mail because: You are the assignee for the bug. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
