Message ID | 20240702081413.5688-1-Dhananjay.Ugwekar@amd.com (mailing list archive) |
---|---|
Headers | show |
Series | AMD Pstate driver fixes | expand |
Forgot to mention the v2 changes, v2 changes: * Add reported-by tags (Gautham) * Modify patch 2 to use amd_pstate_update_perf (Mario) * Modify commit name for patch 1 (Gautham) * Modify commit message for patch 2, from scaling_min/max_freq to just scaling_max_freq, as scaling_min_freq still needs some debugging to work correctly with active mode. Regards, Dhananjay On 7/2/2024 1:44 PM, Dhananjay Ugwekar wrote: > 1. Handle the nominal freq units inconsistency in amd-pstate-ut, which was > leading to the below error on inserting the amd-pstate-ut module. > > [ 4982.498864] amd_pstate_ut: 1 amd_pstate_ut_acpi_cpc_valid success! > [ 4982.498873] amd_pstate_ut: 2 amd_pstate_ut_check_enabled success! > [ 4982.509151] amd_pstate_ut: 3 amd_pstate_ut_check_perf success! > [ 4982.509155] amd_pstate_ut: amd_pstate_ut_check_freq cpu0 max=3709000 >= nominal=2401 > lowest_nonlinear=1903000 > min=400000 > 0, the formula is incorrect! > [ 4982.509157] amd_pstate_ut: 4 amd_pstate_ut_check_freq fail! > > 2. Setting the scaling_max_freq on shared memory CPPC systems was > broken in amd-pstate-epp driver(amd_pstate=active mode). The > scaling_max_freq value was not being propagated to the shared memory area, > so the frequency capping was not being honored. > > Tested on a AMD Zen3 Milan machine(shared memory CPPC): > > stress-ng is running on the system to keep the CPU utilization at 100% > to test the scaling_max_freq capping. > > Before the patch: > We can see below, setting the scaling_max_freq is not taking effect. > > linux/tools/power/x86/turbostat# ./turbostat --Summary > turbostat version 2023.11.07 - Len Brown <lenb@kernel.org> > [Snip] > cpu0: cpufreq driver: amd-pstate-epp > cpu0: cpufreq governor: performance > [Snip] > Avg_MHz Busy% Bzy_MHz TSC_MHz IPC IRQ POLL C1 C2 POLL% C1% C2% CorWatt PkgWatt > 2620 100.00 2620 2026 0.80 164935 0 0 0 0.00 0.00 0.00 176.07 249.18 > 2580 100.00 2580 1995 0.80 162208 0 0 0 0.00 0.00 0.00 173.27 245.37 > 2584 100.00 2584 1998 0.79 162379 0 0 0 0.00 0.00 0.00 173.42 245.68 > 2577 100.00 2577 1996 0.79 162146 0 0 0 0.00 0.00 0.00 173.15 245.41 > 2578 100.00 2578 1996 0.80 162025 0 0 0 0.00 0.00 0.00 173.07 245.46 > 2575 100.00 2575 1996 0.80 162115 0 0 0 0.00 0.00 0.00 172.96 245.41 > 2576 100.00 2576 1996 0.79 161998 0 0 0 0.00 0.00 0.00 172.87 245.32 > linux/tools/power/x86/turbostat# echo 2000000 | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq > 2000000 > linux/tools/power/x86/turbostat# cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq | uniq > 2000000 > linux/tools/power/x86/turbostat# ./turbostat --Summary > turbostat version 2023.11.07 - Len Brown <lenb@kernel.org> > [Snip] > cpu0: cpufreq driver: amd-pstate-epp > cpu0: cpufreq governor: performance > [Snip] > Avg_MHz Busy% Bzy_MHz TSC_MHz IPC IRQ POLL C1 C2 POLL% C1% C2% CorWatt PkgWatt > 2620 100.00 2620 2038 0.79 166103 0 0 2 0.00 0.00 0.00 175.44 250.96 > 2566 100.00 2566 1996 0.79 162038 0 0 0 0.00 0.00 0.00 171.79 245.23 > 2566 100.00 2566 1996 0.79 162289 0 0 0 0.00 0.00 0.00 171.76 245.59 > 2571 100.00 2571 1996 0.80 162034 0 0 0 0.00 0.00 0.00 171.69 245.44 > 2566 100.00 2566 1996 0.79 162179 0 0 0 0.00 0.00 0.00 171.62 245.41 > 2567 100.00 2567 1996 0.79 162028 0 0 0 0.00 0.00 0.00 171.57 245.46 > 2567 100.00 2567 1996 0.80 162037 0 0 0 0.00 0.00 0.00 171.53 245.41 > > After applying the patch: > On setting scaling_max_freq at 2GHz, the CPU frequency gets capped at 2GHz. > > linux/tools/power/x86/turbostat# ./turbostat --Summary > turbostat version 2023.11.07 - Len Brown <lenb@kernel.org> > [Snip] > cpu0: cpufreq driver: amd-pstate-epp > cpu0: cpufreq governor: performance > [Snip] > Avg_MHz Busy% Bzy_MHz TSC_MHz IPC IRQ POLL C1 C2 POLL% C1% C2% CorWatt PkgWatt > 2551 100.00 2551 1956 0.80 165998 0 0 0 0.00 0.00 0.00 171.34 231.22 > 2713 100.00 2713 2078 0.79 175801 0 0 0 0.00 0.00 0.00 181.92 266.13 > 2594 100.00 2594 1991 0.79 162183 0 0 1 0.00 0.00 0.00 173.99 244.50 > 2606 100.00 2606 2003 0.79 162632 0 0 0 0.00 0.00 0.00 174.81 246.51 > 2599 100.00 2599 1996 0.79 162168 0 0 0 0.00 0.00 0.00 174.05 245.46 > linux/tools/power/x86/turbostat# echo 2000000 | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq > 2000000 > linux/tools/power/x86/turbostat# cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq | uniq > 2000000 > linux/tools/power/x86/turbostat# ./turbostat --Summary > turbostat version 2023.11.07 - Len Brown <lenb@kernel.org> > [Snip] > cpu0: cpufreq driver: amd-pstate-epp > cpu0: cpufreq governor: performance > [Snip] > Avg_MHz Busy% Bzy_MHz TSC_MHz IPC IRQ POLL C1 C2 POLL% C1% C2% CorWatt PkgWatt > 2010 100.00 2010 2030 0.80 165565 0 0 0 0.00 0.00 0.00 101.22 173.52 > 1975 100.00 1975 1995 0.80 162042 0 0 0 0.00 0.00 0.00 99.03 169.88 > 1977 100.00 1977 1998 0.80 162559 0 0 0 0.00 0.00 0.00 99.16 170.20 > 1976 100.00 1976 1996 0.80 162243 0 0 0 0.00 0.00 0.00 99.09 170.08 > 1976 100.00 1976 1996 0.80 162490 0 0 0 0.00 0.00 0.00 99.17 170.16 > 1976 100.00 1976 1996 0.80 162056 0 0 0 0.00 0.00 0.00 99.11 170.17 > > Dhananjay Ugwekar (2): > cpufreq/amd-pstate-ut: Convert nominal_freq to khz during comparisons > cpufreq/amd-pstate: Fix the scaling_max_freq setting on shared memory > CPPC systems > > drivers/cpufreq/amd-pstate-ut.c | 12 +++++---- > drivers/cpufreq/amd-pstate.c | 43 ++++++++++++++++++--------------- > 2 files changed, 30 insertions(+), 25 deletions(-) >
On 7/2/2024 3:24, Dhananjay Ugwekar wrote: > Forgot to mention the v2 changes, > > v2 changes: > * Add reported-by tags (Gautham) > * Modify patch 2 to use amd_pstate_update_perf (Mario) > * Modify commit name for patch 1 (Gautham) > * Modify commit message for patch 2, from scaling_min/max_freq to > just scaling_max_freq, as scaling_min_freq still needs some debugging > to work correctly with active mode. > > Regards, > Dhananjay > Thanks! On it's own it looks good. I've added it to superm1/bleeding-edge for some more testing. While testing I did uncover some other issues that I dropped some other patches for review if you can please look them over. https://lore.kernel.org/linux-pm/20240702171515.6780-1-mario.limonciello@amd.com/T/#m1304e6bfe80b7a76e41d551784542fc1038e03e8 Thanks,