diff options
| -rw-r--r-- | Documentation/power/energy-model.rst | 18 | ||||
| -rw-r--r-- | Documentation/scheduler/sched-energy.rst | 8 | ||||
| -rw-r--r-- | drivers/opp/core.c | 2 | ||||
| -rw-r--r-- | drivers/opp/of.c | 4 | ||||
| -rw-r--r-- | drivers/powercap/intel_rapl_msr.c | 1 | ||||
| -rw-r--r-- | drivers/powercap/powercap_sys.c | 13 |
6 files changed, 22 insertions, 24 deletions
diff --git a/Documentation/power/energy-model.rst b/Documentation/power/energy-model.rst index cbdf7520aaa6..0d4644d72767 100644 --- a/Documentation/power/energy-model.rst +++ b/Documentation/power/energy-model.rst @@ -14,8 +14,8 @@ subsystems willing to use that information to make energy-aware decisions. The source of the information about the power consumed by devices can vary greatly from one platform to another. These power costs can be estimated using devicetree data in some cases. In others, the firmware will know better. -Alternatively, userspace might be best positioned. And so on. In order to avoid -each and every client subsystem to re-implement support for each and every +Alternatively, userspace might be best positioned. In order to avoid +having each and every client subsystem re-implement support for each and every possible source of information on its own, the EM framework intervenes as an abstraction layer which standardizes the format of power cost tables in the kernel, hence enabling to avoid redundant work. @@ -32,7 +32,7 @@ be found in the Intelligent Power Allocation in Documentation/driver-api/thermal/power_allocator.rst. Kernel subsystems might implement automatic detection to check whether EM registered devices have inconsistent scale (based on EM internal flag). -Important thing to keep in mind is that when the power values are expressed in +An important thing to keep in mind is that when the power values are expressed in an 'abstract scale' deriving real energy in micro-Joules would not be possible. The figure below depicts an example of drivers (Arm-specific here, but the @@ -82,7 +82,7 @@ using kref mechanism. The device driver which provided the new EM at runtime, should call EM API to free it safely when it's no longer needed. The EM framework will handle the clean-up when it's possible. -The kernel code which want to modify the EM values is protected from concurrent +The kernel code which wants to modify the EM values is protected from concurrent access using a mutex. Therefore, the device driver code must run in sleeping context when it tries to modify the EM. @@ -113,7 +113,7 @@ Registration of 'advanced' EM ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The 'advanced' EM gets its name due to the fact that the driver is allowed -to provide more precised power model. It's not limited to some implemented math +to provide a more precise power model. It's not limited to some implemented math formula in the framework (like it is in 'simple' EM case). It can better reflect the real power measurements performed for each performance state. Thus, this registration method should be preferred in case considering EM static power @@ -172,7 +172,7 @@ Registration of 'simple' EM ~~~~~~~~~~~~~~~~~~~~~~~~~~~ The 'simple' EM is registered using the framework helper function -cpufreq_register_em_with_opp(). It implements a power model which is tight to +cpufreq_register_em_with_opp(). It implements a power model which is tied to a math formula:: Power = C * V^2 * f @@ -251,7 +251,7 @@ It returns the 'struct em_perf_state' pointer which is an array of performance states in ascending order. This function must be called in the RCU read lock section (after the rcu_read_lock()). When the EM table is not needed anymore there is a need to -call rcu_real_unlock(). In this way the EM safely uses the RCU read section +call rcu_read_unlock(). In this way the EM safely uses the RCU read section and protects the users. It also allows the EM framework to manage the memory and free it. More details how to use it can be found in Section 3.2 in the example driver. @@ -308,12 +308,12 @@ EM framework:: 05 06 /* Use the 'foo' protocol to ceil the frequency */ 07 freq = foo_get_freq_ceil(dev, *KHz); - 08 if (freq < 0); + 08 if (freq < 0) 09 return freq; 10 11 /* Estimate the power cost for the dev at the relevant freq. */ 12 power = foo_estimate_power(dev, freq); - 13 if (power < 0); + 13 if (power < 0) 14 return power; 15 16 /* Return the values to the EM framework */ diff --git a/Documentation/scheduler/sched-energy.rst b/Documentation/scheduler/sched-energy.rst index 70e2921ef725..4e47aaf103eb 100644 --- a/Documentation/scheduler/sched-energy.rst +++ b/Documentation/scheduler/sched-energy.rst @@ -244,7 +244,7 @@ Example 2. From these calculations, the Case 1 has the lowest total energy. So CPU 1 - is be the best candidate from an energy-efficiency standpoint. + is the best candidate from an energy-efficiency standpoint. Big CPUs are generally more power hungry than the little ones and are thus used mainly when a task doesn't fit the littles. However, little CPUs aren't always @@ -252,7 +252,7 @@ necessarily more energy-efficient than big CPUs. For some systems, the high OPPs of the little CPUs can be less energy-efficient than the lowest OPPs of the bigs, for example. So, if the little CPUs happen to have enough utilization at a specific point in time, a small task waking up at that moment could be better -of executing on the big side in order to save energy, even though it would fit +off executing on the big side in order to save energy, even though it would fit on the little side. And even in the case where all OPPs of the big CPUs are less energy-efficient @@ -285,7 +285,7 @@ much that can be done by the scheduler to save energy without severely harming throughput. In order to avoid hurting performance with EAS, CPUs are flagged as 'over-utilized' as soon as they are used at more than 80% of their compute capacity. As long as no CPUs are over-utilized in a root domain, load balancing -is disabled and EAS overridess the wake-up balancing code. EAS is likely to load +is disabled and EAS overrides the wake-up balancing code. EAS is likely to load the most energy efficient CPUs of the system more than the others if that can be done without harming throughput. So, the load-balancer is disabled to prevent it from breaking the energy-efficient task placement found by EAS. It is safe to @@ -385,7 +385,7 @@ Using EAS with any other governor than schedutil is not supported. 6.5 Scale-invariant utilization signals ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -In order to make accurate prediction across CPUs and for all performance +In order to make accurate predictions across CPUs and for all performance states, EAS needs frequency-invariant and CPU-invariant PELT signals. These can be obtained using the architecture-defined arch_scale{cpu,freq}_capacity() callbacks. diff --git a/drivers/opp/core.c b/drivers/opp/core.c index dbebb8c829bc..ae43c656f108 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -241,7 +241,7 @@ unsigned int dev_pm_opp_get_level(struct dev_pm_opp *opp) { if (IS_ERR_OR_NULL(opp) || !opp->available) { pr_err("%s: Invalid parameters\n", __func__); - return 0; + return U32_MAX; } return opp->level; diff --git a/drivers/opp/of.c b/drivers/opp/of.c index 1e0d0adb18e1..a268c2b250c0 100644 --- a/drivers/opp/of.c +++ b/drivers/opp/of.c @@ -956,7 +956,6 @@ free_opp: /* Initializes OPP tables based on new bindings */ static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table) { - struct device_node *np; int ret, count = 0; struct dev_pm_opp *opp; @@ -971,13 +970,12 @@ static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table) } /* We have opp-table node now, iterate over it and add OPPs */ - for_each_available_child_of_node(opp_table->np, np) { + for_each_available_child_of_node_scoped(opp_table->np, np) { opp = _opp_add_static_v2(opp_table, dev, np); if (IS_ERR(opp)) { ret = PTR_ERR(opp); dev_err(dev, "%s: Failed to add OPP, %d\n", __func__, ret); - of_node_put(np); goto remove_static_opp; } else if (opp) { count++; diff --git a/drivers/powercap/intel_rapl_msr.c b/drivers/powercap/intel_rapl_msr.c index 9a7e150b3536..a2bc0a9c1e10 100644 --- a/drivers/powercap/intel_rapl_msr.c +++ b/drivers/powercap/intel_rapl_msr.c @@ -162,6 +162,7 @@ static int rapl_msr_write_raw(int cpu, struct reg_action *ra) /* List of verified CPUs. */ static const struct x86_cpu_id pl4_support_ids[] = { + X86_MATCH_VFM(INTEL_ICELAKE_L, NULL), X86_MATCH_VFM(INTEL_TIGERLAKE_L, NULL), X86_MATCH_VFM(INTEL_ALDERLAKE, NULL), X86_MATCH_VFM(INTEL_ALDERLAKE_L, NULL), diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c index 1ff369880beb..f3b2ae635305 100644 --- a/drivers/powercap/powercap_sys.c +++ b/drivers/powercap/powercap_sys.c @@ -27,7 +27,7 @@ static ssize_t _attr##_show(struct device *dev, \ \ if (power_zone->ops->get_##_attr) { \ if (!power_zone->ops->get_##_attr(power_zone, &value)) \ - len = sprintf(buf, "%lld\n", value); \ + len = sysfs_emit(buf, "%lld\n", value); \ } \ \ return len; \ @@ -75,7 +75,7 @@ static ssize_t show_constraint_##_attr(struct device *dev, \ pconst = &power_zone->constraints[id]; \ if (pconst && pconst->ops && pconst->ops->get_##_attr) { \ if (!pconst->ops->get_##_attr(power_zone, id, &value)) \ - len = sprintf(buf, "%lld\n", value); \ + len = sysfs_emit(buf, "%lld\n", value); \ } \ \ return len; \ @@ -171,9 +171,8 @@ static ssize_t show_constraint_name(struct device *dev, if (pconst && pconst->ops && pconst->ops->get_name) { name = pconst->ops->get_name(power_zone, id); if (name) { - sprintf(buf, "%.*s\n", POWERCAP_CONSTRAINT_NAME_LEN - 1, - name); - len = strlen(buf); + len = sysfs_emit(buf, "%.*s\n", + POWERCAP_CONSTRAINT_NAME_LEN - 1, name); } } @@ -350,7 +349,7 @@ static ssize_t name_show(struct device *dev, { struct powercap_zone *power_zone = to_powercap_zone(dev); - return sprintf(buf, "%s\n", power_zone->name); + return sysfs_emit(buf, "%s\n", power_zone->name); } static DEVICE_ATTR_RO(name); @@ -438,7 +437,7 @@ static ssize_t enabled_show(struct device *dev, mode = false; } - return sprintf(buf, "%d\n", mode); + return sysfs_emit(buf, "%d\n", mode); } static ssize_t enabled_store(struct device *dev, |