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| author | Jakub Kicinski <kuba@kernel.org> | 2022-11-29 13:04:52 -0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-11-29 13:04:52 -0800 |
| commit | f2bb566f5c977ff010baaa9e5e14d9a75b06e5f2 (patch) | |
| tree | 6359cc9169bd06bfb8b757a534c82886df605b71 /Documentation/admin-guide | |
| parent | 7a945ce0c19bbdf821d5f7ce1515e7fb8e444465 (diff) | |
| parent | 01f856ae6d0ca5ad0505b79bf2d22d7ca439b2a1 (diff) | |
| download | lwn-f2bb566f5c977ff010baaa9e5e14d9a75b06e5f2.tar.gz lwn-f2bb566f5c977ff010baaa9e5e14d9a75b06e5f2.zip | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/lib/bpf/ringbuf.c
927cbb478adf ("libbpf: Handle size overflow for ringbuf mmap")
b486d19a0ab0 ("libbpf: checkpatch: Fixed code alignments in ringbuf.c")
https://lore.kernel.org/all/20221121122707.44d1446a@canb.auug.org.au/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 11 | ||||
| -rw-r--r-- | Documentation/admin-guide/pm/amd-pstate.rst | 30 |
2 files changed, 24 insertions, 17 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a465d5242774..42af9ca0127e 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6959,3 +6959,14 @@ memory, and other data can't be written using xmon commands. off xmon is disabled. + + amd_pstate= [X86] + disable + Do not enable amd_pstate as the default + scaling driver for the supported processors + passive + Use amd_pstate as a scaling driver, driver requests a + desired performance on this abstract scale and the power + management firmware translates the requests into actual + hardware states (core frequency, data fabric and memory + clocks etc.) diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index 8f3d30c5a0d8..06e23538f79c 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -283,23 +283,19 @@ efficiency frequency management method on AMD processors. Kernel Module Options for ``amd-pstate`` ========================================= -.. _shared_mem: - -``shared_mem`` -Use a module param (shared_mem) to enable related processors manually with -**amd_pstate.shared_mem=1**. -Due to the performance issue on the processors with `Shared Memory Support -<perf_cap_>`_, we disable it presently and will re-enable this by default -once we address performance issue with this solution. - -To check whether the current processor is using `Full MSR Support <perf_cap_>`_ -or `Shared Memory Support <perf_cap_>`_ : :: - - ray@hr-test1:~$ lscpu | grep cppc - Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf rapl pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 hw_pstate ssbd mba ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr rdpru wbnoinvd cppc arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif v_spec_ctrl umip pku ospke vaes vpclmulqdq rdpid overflow_recov succor smca fsrm - -If the CPU flags have ``cppc``, then this processor supports `Full MSR Support -<perf_cap_>`_. Otherwise, it supports `Shared Memory Support <perf_cap_>`_. +Passive Mode +------------ + +``amd_pstate=passive`` + +It will be enabled if the ``amd_pstate=passive`` is passed to the kernel in the command line. +In this mode, ``amd_pstate`` driver software specifies a desired QoS target in the CPPC +performance scale as a relative number. This can be expressed as percentage of nominal +performance (infrastructure max). Below the nominal sustained performance level, +desired performance expresses the average performance level of the processor subject +to the Performance Reduction Tolerance register. Above the nominal performance level, +processor must provide at least nominal performance requested and go higher if current +operating conditions allow. ``cpupower`` tool support for ``amd-pstate`` |
