| Message ID | cover.1623825725.git.viresh.kumar@linaro.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | cpufreq: cppc: Add support for frequency invariance | expand |
On Wed, 16 Jun 2021 at 08:48, Viresh Kumar <viresh.kumar@linaro.org> wrote: > > Hello, > > Changes since V1: > > - Few of the patches migrating users to ->exit() callback are posted separately. > > - The CPPC patch was completely reverted and so the support for FIE is again > added here from scratch. > > - The start_cpu() and stop_cpu() interface is reworked a little so stop_cpu() is > only ever called for a CPU if start_cpu() was called for it earlier. > > - A new patch to implement RCU locking in arch_topology core to avoid some > races. > > - Some cleanup and very clear/separate paths for FIE in cppc driver now. > > > -------------------------8<------------------------- > > CPPC cpufreq driver is used for ARM servers and this patch series tries to > provide counter-based frequency invariance support for them in the absence for > architecture specific counters (like AMUs). > > This was reverted earlier for the 5.13 kernel after Qian Cai reported kernel > oops during suspend/resume. > > This is based of pm/linux-next + a cleanup patchset: > > https://lore.kernel.org/linux-pm/cover.1623825358.git.viresh.kumar@linaro.org/ > > All the patches are pushed here together for people to run. > > https://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm.git/log/?h=cpufreq/cppc > > This is tested on my Hikey platform (without the actual read/write to > performance counters), with this script for over an hour: > > while true; do > for i in `seq 1 7`; > do > echo 0 > /sys/devices/system/cpu/cpu$i/online; > done; > > for i in `seq 1 7`; > do > echo 1 > /sys/devices/system/cpu/cpu$i/online; > done; > done > > > Vincent will be giving this patchset a try on ThunderX2. I tested your branch and got the following while booting: [ 24.454543] zswap: loaded using pool lzo/zbud [ 24.454753] pstore: Using crash dump compression: deflate [ 24.454776] AppArmor: AppArmor sha1 policy hashing enabled [ 24.454784] ima: No TPM chip found, activating TPM-bypass! [ 24.454789] ima: Allocated hash algorithm: sha256 [ 24.454801] ima: No architecture policies found [ 24.455750] pcieport 0000:0f:00.0: Adding to iommu group 0 [ 24.893888] ------------[ cut here ]------------ [ 24.893891] WARNING: CPU: 95 PID: 1442 at drivers/cpufreq/cppc_cpufreq.c:123 cppc_scale_freq_workfn+0xc8/0xf8 [ 24.893901] Modules linked in: [ 24.893906] CPU: 95 PID: 1442 Comm: cppc_fie Not tainted 5.13.0-rc6+ #359 [ 24.893910] Hardware name: To be filled by O.E.M. Saber/Saber, BIOS 0ACKL026 03/19/2019 [ 24.893912] pstate: 20400009 (nzCv daif +PAN -UAO -TCO BTYPE=--) [ 24.893915] pc : cppc_scale_freq_workfn+0xc8/0xf8 [ 24.893918] lr : cppc_scale_freq_workfn+0x5c/0xf8 [ 24.893921] sp : ffff80003727bd90 [ 24.893922] x29: ffff80003727bd90 x28: 0000000000000000 x27: ffff800010ec2000 [ 24.893928] x26: ffff800010ec2000 x25: ffff8000107c3d90 x24: 0000000000000001 [ 24.893932] x23: ffff000816244880 x22: ffff8000113f9000 x21: ffff009f825a0a80 [ 24.893935] x20: ffff009efc394220 x19: ffff800011199000 x18: 000000000000001b [ 24.893939] x17: 0000000000000007 x16: 0000000000000001 x15: 00000000000000bf [ 24.893943] x14: 0000000000000016 x13: 000000000000029b x12: 0000000000000016 [ 24.893946] x11: 0000000000000000 x10: 0000000000000000 x9 : ffff009efc6958c0 [ 24.893950] x8 : ffff009efc394248 x7 : 0000000002bde780 x6 : 00000000ffffffff [ 24.893954] x5 : 00000000916e502a x4 : 00000000d9730e80 x3 : ffffffffffffffff [ 24.893958] x2 : 00000000001e8480 x1 : 00000000002625a0 x0 : 0000000000000401 [ 24.893962] Call trace: [ 24.893964] cppc_scale_freq_workfn+0xc8/0xf8 [ 24.893967] kthread_worker_fn+0x110/0x318 [ 24.893971] kthread+0xf4/0x120 [ 24.893973] ret_from_fork+0x10/0x18 [ 24.893977] ---[ end trace ea6dbaf832bce3e4 ]--- > > Meanwhile it is up for review. Ideally I would like to get this merged for 5.14, > but lets see how it goes. > > Thanks. > > -- > Viresh > > Viresh Kumar (3): > cpufreq: Add start_cpu() and stop_cpu() callbacks > arch_topology: Avoid use-after-free for scale_freq_data > cpufreq: CPPC: Add support for frequency invariance > > Documentation/cpu-freq/cpu-drivers.rst | 7 +- > drivers/base/arch_topology.c | 27 ++- > drivers/cpufreq/Kconfig.arm | 10 ++ > drivers/cpufreq/cppc_cpufreq.c | 232 +++++++++++++++++++++++-- > drivers/cpufreq/cpufreq.c | 19 +- > include/linux/arch_topology.h | 1 + > include/linux/cpufreq.h | 5 +- > kernel/sched/core.c | 1 + > 8 files changed, 272 insertions(+), 30 deletions(-) > > -- > 2.31.1.272.g89b43f80a514 >
On 16-06-21, 12:02, Vincent Guittot wrote: > I tested your branch and got the following while booting: > > [ 24.454543] zswap: loaded using pool lzo/zbud > [ 24.454753] pstore: Using crash dump compression: deflate > [ 24.454776] AppArmor: AppArmor sha1 policy hashing enabled > [ 24.454784] ima: No TPM chip found, activating TPM-bypass! > [ 24.454789] ima: Allocated hash algorithm: sha256 > [ 24.454801] ima: No architecture policies found > [ 24.455750] pcieport 0000:0f:00.0: Adding to iommu group 0 > [ 24.893888] ------------[ cut here ]------------ > [ 24.893891] WARNING: CPU: 95 PID: 1442 at > drivers/cpufreq/cppc_cpufreq.c:123 cppc_scale_freq_workfn+0xc8/0xf8 > [ 24.893901] Modules linked in: > [ 24.893906] CPU: 95 PID: 1442 Comm: cppc_fie Not tainted 5.13.0-rc6+ #359 > [ 24.893910] Hardware name: To be filled by O.E.M. Saber/Saber, BIOS > 0ACKL026 03/19/2019 > [ 24.893912] pstate: 20400009 (nzCv daif +PAN -UAO -TCO BTYPE=--) > [ 24.893915] pc : cppc_scale_freq_workfn+0xc8/0xf8 > [ 24.893918] lr : cppc_scale_freq_workfn+0x5c/0xf8 > [ 24.893921] sp : ffff80003727bd90 > [ 24.893922] x29: ffff80003727bd90 x28: 0000000000000000 x27: ffff800010ec2000 > [ 24.893928] x26: ffff800010ec2000 x25: ffff8000107c3d90 x24: 0000000000000001 > [ 24.893932] x23: ffff000816244880 x22: ffff8000113f9000 x21: ffff009f825a0a80 > [ 24.893935] x20: ffff009efc394220 x19: ffff800011199000 x18: 000000000000001b > [ 24.893939] x17: 0000000000000007 x16: 0000000000000001 x15: 00000000000000bf > [ 24.893943] x14: 0000000000000016 x13: 000000000000029b x12: 0000000000000016 > [ 24.893946] x11: 0000000000000000 x10: 0000000000000000 x9 : ffff009efc6958c0 > [ 24.893950] x8 : ffff009efc394248 x7 : 0000000002bde780 x6 : 00000000ffffffff > [ 24.893954] x5 : 00000000916e502a x4 : 00000000d9730e80 x3 : ffffffffffffffff > [ 24.893958] x2 : 00000000001e8480 x1 : 00000000002625a0 x0 : 0000000000000401 > [ 24.893962] Call trace: > [ 24.893964] cppc_scale_freq_workfn+0xc8/0xf8 > [ 24.893967] kthread_worker_fn+0x110/0x318 > [ 24.893971] kthread+0xf4/0x120 > [ 24.893973] ret_from_fork+0x10/0x18 > [ 24.893977] ---[ end trace ea6dbaf832bce3e4 ]--- Thanks Vincent. This is triggering from cppc_scale_freq_workfn(): if (WARN_ON(local_freq_scale > 1024)) Looks like there is something fishy about the perf calculations here after reading the counters, we tried to scale that in the range 0-1024 and it came larger than that. Will keep you posted.
Hello, Changes since V1: - Few of the patches migrating users to ->exit() callback are posted separately. - The CPPC patch was completely reverted and so the support for FIE is again added here from scratch. - The start_cpu() and stop_cpu() interface is reworked a little so stop_cpu() is only ever called for a CPU if start_cpu() was called for it earlier. - A new patch to implement RCU locking in arch_topology core to avoid some races. - Some cleanup and very clear/separate paths for FIE in cppc driver now. -------------------------8<------------------------- CPPC cpufreq driver is used for ARM servers and this patch series tries to provide counter-based frequency invariance support for them in the absence for architecture specific counters (like AMUs). This was reverted earlier for the 5.13 kernel after Qian Cai reported kernel oops during suspend/resume. This is based of pm/linux-next + a cleanup patchset: https://lore.kernel.org/linux-pm/cover.1623825358.git.viresh.kumar@linaro.org/ All the patches are pushed here together for people to run. https://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm.git/log/?h=cpufreq/cppc This is tested on my Hikey platform (without the actual read/write to performance counters), with this script for over an hour: while true; do for i in `seq 1 7`; do echo 0 > /sys/devices/system/cpu/cpu$i/online; done; for i in `seq 1 7`; do echo 1 > /sys/devices/system/cpu/cpu$i/online; done; done Vincent will be giving this patchset a try on ThunderX2. Meanwhile it is up for review. Ideally I would like to get this merged for 5.14, but lets see how it goes. Thanks. -- Viresh Viresh Kumar (3): cpufreq: Add start_cpu() and stop_cpu() callbacks arch_topology: Avoid use-after-free for scale_freq_data cpufreq: CPPC: Add support for frequency invariance Documentation/cpu-freq/cpu-drivers.rst | 7 +- drivers/base/arch_topology.c | 27 ++- drivers/cpufreq/Kconfig.arm | 10 ++ drivers/cpufreq/cppc_cpufreq.c | 232 +++++++++++++++++++++++-- drivers/cpufreq/cpufreq.c | 19 +- include/linux/arch_topology.h | 1 + include/linux/cpufreq.h | 5 +- kernel/sched/core.c | 1 + 8 files changed, 272 insertions(+), 30 deletions(-)