summaryrefslogtreecommitdiff
path: root/drivers/cpufreq
AgeCommit message (Collapse)AuthorFilesLines
2016-03-09Revert "cpufreq: Drop rwsem lock around CPUFREQ_GOV_POLICY_EXIT"Viresh Kumar1-5/+0
Earlier, when the struct freq-attr was used to represent governor attributes, the standard cpufreq show/store sysfs attribute callbacks were applied to the governor tunable attributes and they always acquire the policy->rwsem lock before carrying out the operation. That could have resulted in an ABBA deadlock if governor tunable attributes are removed under policy->rwsem while one of them is being accessed concurrently (if sysfs attributes removal wins the race, it will wait for the access to complete with policy->rwsem held while the attribute callback will block on policy->rwsem indefinitely). We attempted to address this issue by dropping policy->rwsem around governor tunable attributes removal (that is, around invocations of the ->governor callback with the event arg equal to CPUFREQ_GOV_POLICY_EXIT) in cpufreq_set_policy(), but that opened up race conditions that had not been possible with policy->rwsem held all the time. The previous commit, "cpufreq: governor: New sysfs show/store callbacks for governor tunables", fixed the original ABBA deadlock by adding new governor specific show/store callbacks. We don't have to drop rwsem around invocations of governor event CPUFREQ_GOV_POLICY_EXIT anymore, and original fix can be reverted now. Fixes: 955ef4833574 (cpufreq: Drop rwsem lock around CPUFREQ_GOV_POLICY_EXIT) Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reported-by: Juri Lelli <juri.lelli@arm.com> Tested-by: Juri Lelli <juri.lelli@arm.com> Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09cpufreq: governor: Drop unused macros for creating governor tunable attributesViresh Kumar1-89/+0
The previous commit introduced a new set of macros for creating sysfs attributes that represent governor tunables and the old macros used for this purpose are not needed any more, so drop them. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Juri Lelli <juri.lelli@arm.com> Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09cpufreq: governor: New sysfs show/store callbacks for governor tunablesViresh Kumar4-103/+144
The ondemand and conservative governors use the global-attr or freq-attr structures to represent sysfs attributes corresponding to their tunables (which of them is actually used depends on whether or not different policy objects can use the same governor with different tunables at the same time and, consequently, on where those attributes are located in sysfs). Unfortunately, in the freq-attr case, the standard cpufreq show/store sysfs attribute callbacks are applied to the governor tunable attributes and they always acquire the policy->rwsem lock before carrying out the operation. That may lead to an ABBA deadlock if governor tunable attributes are removed under policy->rwsem while one of them is being accessed concurrently (if sysfs attributes removal wins the race, it will wait for the access to complete with policy->rwsem held while the attribute callback will block on policy->rwsem indefinitely). We attempted to address this issue by dropping policy->rwsem around governor tunable attributes removal (that is, around invocations of the ->governor callback with the event arg equal to CPUFREQ_GOV_POLICY_EXIT) in cpufreq_set_policy(), but that opened up race conditions that had not been possible with policy->rwsem held all the time. Therefore policy->rwsem cannot be dropped in cpufreq_set_policy() at any point, but the deadlock situation described above must be avoided too. To that end, use the observation that in principle governor tunables may be represented by the same data type regardless of whether the governor is system-wide or per-policy and introduce a new structure, struct governor_attr, for representing them and new corresponding macros for creating show/store sysfs callbacks for them. Also make their parent kobject use a new kobject type whose default show/store callbacks are not related to the standard core cpufreq ones in any way (and they don't acquire policy->rwsem in particular). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Juri Lelli <juri.lelli@arm.com> Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> [ rjw: Subject & changelog + rebase ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09cpufreq: governor: Move common tunables to 'struct dbs_data'Viresh Kumar4-83/+47
There are a few common tunables shared between the ondemand and conservative governors. Move them to struct dbs_data to simplify code. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Juri Lelli <juri.lelli@arm.com> Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09cpufreq: governor: Create generic macro for common tunablesViresh Kumar3-24/+28
Some tunables are present in governor-specific structures, whereas one (min_sampling_rate) is located directly in struct dbs_data. There is a special macro for creating its sysfs attribute and the show/store callbacks, but since more tunables are going to be moved to struct dbs_data, a new generic macro for such cases will be useful, so add it and use it for min_sampling_rate. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Juri Lelli <juri.lelli@arm.com> Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09cpufreq: governor: Drop pointless goto from cpufreq_governor_init()Rafael J. Wysocki1-4/+3
It is silly to jump around "return 0", so don't do that. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Rename skip_work to work_countRafael J. Wysocki2-8/+8
The skip_work field in struct policy_dbs_info technically is a counter, so give it a new name to reflect that. No functional changes. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Symmetrize cpu_dbs_info initialization and cleanupRafael J. Wysocki1-8/+13
Make the initialization of struct cpu_dbs_info objects in alloc_policy_dbs_info() and the code that cleans them up in free_policy_dbs_info() more symmetrical. In particular, set/clear the update_util.func field in those functions along with the policy_dbs field. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Rearrange governor data structuresRafael J. Wysocki5-60/+68
The struct policy_dbs_info objects representing per-policy governor data are not accessible directly from the corresponding policy objects. To access them, one has to get a pointer to the struct cpu_dbs_info of policy->cpu and use the policy_dbs field of that which isn't really straightforward. To address that rearrange the governor data structures so the governor_data pointer in struct cpufreq_policy will point to struct policy_dbs_info (instead of struct dbs_data) and that will contain a pointer to struct dbs_data. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Simplify cpufreq_governor_limits()Rafael J. Wysocki1-9/+8
Use the observation that cpufreq_governor_limits() doesn't have to get to the policy object it wants to manipulate by walking the reference chain cdbs->policy_dbs->policy, as the final pointer is actually equal to its argument, and make it access the policy object directy via its argument. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Drop cpu argument from dbs_check_cpu()Rafael J. Wysocki4-10/+8
Since policy->cpu is always passed as the second argument to dbs_check_cpu(), it is not really necessary to pass it, because the function can obtain that value via its first argument just fine. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Rename cpu_common_dbs_info to policy_dbs_infoRafael J. Wysocki4-86/+86
The struct cpu_common_dbs_info structure represents the per-policy part of the governor data (for the ondemand and conservative governors), but its name doesn't reflect its purpose. Rename it to struct policy_dbs_info and rename variables related to it accordingly. No functional changes. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Drop the gov pointer from struct dbs_dataRafael J. Wysocki5-38/+39
Since it is possible to obtain a pointer to struct dbs_governor from a pointer to the struct governor embedded in it with the help of container_of(), the additional gov pointer in struct dbs_data isn't really necessary. Drop that pointer and make the code using it reach the dbs_governor object via policy->governor. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Rework cpufreq_governor_dbs()Rafael J. Wysocki4-27/+8
Since it is possible to obtain a pointer to struct dbs_governor from a pointer to the struct governor embedded in it via container_of(), the second argument of cpufreq_governor_init() is not necessary. Accordingly, cpufreq_governor_dbs() doesn't need its second argument either and the ->governor callbacks for both the ondemand and conservative governors may be set to cpufreq_governor_dbs() directly. Make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Saravana Kannan <skannan@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Rename some data types and variablesRafael J. Wysocki5-59/+59
The ondemand and conservative governors are represented by struct common_dbs_data whose name doesn't reflect the purpose it is used for, so rename it to struct dbs_governor and rename variables of that type accordingly. No functional changes. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Put governor structure into common_dbs_dataRafael J. Wysocki3-51/+58
For the ondemand and conservative governors (generally, governors that use the common code in cpufreq_governor.c), there are two static data structures representing the governor, the struct governor structure (the interface to the cpufreq core) and the struct common_dbs_data one (the interface to the cpufreq_governor.c code). There's no fundamental reason why those two structures have to be separate. Moreover, if the struct governor one is included into struct common_dbs_data, it will be possible to reach the latter from the policy via its policy->governor pointer, so it won't be necessary to pass a separate pointer to it around. For this reason, embed struct governor in struct common_dbs_data. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Saravana Kannan <skannan@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Avoid passing dbs_data pointers around unnecessarilyRafael J. Wysocki1-41/+27
Do not pass struct dbs_data pointers to the family of functions implementing governor operations in cpufreq_governor.c as they can take that pointer from policy->governor by themselves. The cpufreq_governor_init() case is slightly more complicated, since policy->governor may be NULL when it is invoked, but then it can reach the pointer in question via its cdata argument just fine. While at it, rework cpufreq_governor_dbs() to avoid a pointless policy_governor check in the CPUFREQ_GOV_POLICY_INIT case. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Use common mutex for dbs_data protectionRafael J. Wysocki4-11/+8
Every governor relying on the common code in cpufreq_governor.c has to provide its own mutex in struct common_dbs_data. However, there actually is no need to have a separate mutex per governor for this purpose, they may be using the same global mutex just fine. Accordingly, introduce a single common mutex for that and drop the mutex field from struct common_dbs_data. That at least will ensure that the mutex is always present and initialized regardless of what the particular governors do. Another benefit is that the common code does not need a pointer to a governor-related structure to get to the mutex which sometimes helps. Finally, it makes the code generally easier to follow. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Saravana Kannan <skannan@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09cpufreq: governor: Replace timers with utilization update callbacksRafael J. Wysocki5-120/+114
Instead of using a per-CPU deferrable timer for queuing up governor work items, register a utilization update callback that will be invoked from the scheduler on utilization changes. The sampling rate is still the same as what was used for the deferrable timers and the added irq_work overhead should be offset by the eliminated timers overhead, so in theory the functional impact of this patch should not be significant. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
2016-03-09cpufreq: intel_pstate: Replace timers with utilization update callbacksRafael J. Wysocki1-64/+39
Instead of using a per-CPU deferrable timer for utilization sampling and P-states adjustments, register a utilization update callback that will be invoked from the scheduler on utilization changes. The sampling rate is still the same as what was used for the deferrable timers, so the functional impact of this patch should not be significant. Based on an earlier patch from Srinivas Pandruvada. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-03-09cpufreq: Add mechanism for registering utilization update callbacksRafael J. Wysocki1-0/+45
Introduce a mechanism by which parts of the cpufreq subsystem ("setpolicy" drivers or the core) can register callbacks to be executed from cpufreq_update_util() which is invoked by the scheduler's update_load_avg() on CPU utilization changes. This allows the "setpolicy" drivers to dispense with their timers and do all of the computations they need and frequency/voltage adjustments in the update_load_avg() code path, among other things. The update_load_avg() changes were suggested by Peter Zijlstra. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@kernel.org>
2016-02-05cpufreq: Clean up default and fallback governor setupRafael J. Wysocki6-50/+71
The preprocessor magic used for setting the default cpufreq governor (and for using the performance governor as a fallback one for that matter) is really nasty, so replace it with __weak functions and overrides. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Saravana Kannan <skannan@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-01-29Merge branches 'pm-cpuidle', 'pm-cpufreq', 'pm-domains' and 'pm-sleep'Rafael J. Wysocki4-15/+19
* pm-cpuidle: cpuidle: coupled: remove unused define cpuidle_coupled_lock cpuidle: fix fallback mechanism for suspend to idle in absence of enter_freeze * pm-cpufreq: cpufreq: cpufreq-dt: avoid uninitialized variable warnings: cpufreq: pxa2xx: fix pxa_cpufreq_change_voltage prototype cpufreq: Use list_is_last() to check last entry of the policy list cpufreq: Fix NULL reference crash while accessing policy->governor_data * pm-domains: PM / Domains: Fix typo in comment PM / Domains: Fix potential deadlock while adding/removing subdomains PM / domains: fix lockdep issue for all subdomains * pm-sleep: PM: APM_EMULATION does not depend on PM
2016-01-28cpufreq: cpufreq-dt: avoid uninitialized variable warnings:Arnd Bergmann1-8/+7
gcc warns quite a bit about values returned from allocate_resources() in cpufreq-dt.c: cpufreq-dt.c: In function 'cpufreq_init': cpufreq-dt.c:327:6: error: 'cpu_dev' may be used uninitialized in this function [-Werror=maybe-uninitialized] cpufreq-dt.c:197:17: note: 'cpu_dev' was declared here cpufreq-dt.c:376:2: error: 'cpu_clk' may be used uninitialized in this function [-Werror=maybe-uninitialized] cpufreq-dt.c:199:14: note: 'cpu_clk' was declared here cpufreq-dt.c: In function 'dt_cpufreq_probe': cpufreq-dt.c:461:2: error: 'cpu_clk' may be used uninitialized in this function [-Werror=maybe-uninitialized] cpufreq-dt.c:447:14: note: 'cpu_clk' was declared here The problem is that it's slightly hard for gcc to follow return codes across PTR_ERR() calls. This patch uses explicit assignments to the "ret" variable to make it easier for gcc to verify that the code is actually correct, without the need to add a bogus initialization. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-28cpufreq: pxa2xx: fix pxa_cpufreq_change_voltage prototypeArnd Bergmann1-1/+1
There are two definitions of pxa_cpufreq_change_voltage, with slightly different prototypes after one of them had its argument marked 'const'. Now the other one (for !CONFIG_REGULATOR) produces a harmless warning: drivers/cpufreq/pxa2xx-cpufreq.c: In function 'pxa_set_target': drivers/cpufreq/pxa2xx-cpufreq.c:291:36: warning: passing argument 1 of 'pxa_cpufreq_change_voltage' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers] ret = pxa_cpufreq_change_voltage(&pxa_freq_settings[idx]); ^ drivers/cpufreq/pxa2xx-cpufreq.c:205:12: note: expected 'struct pxa_freqs *' but argument is of type 'const struct pxa_freqs *' static int pxa_cpufreq_change_voltage(struct pxa_freqs *pxa_freq) ^ This changes the prototype in the same way as the other, which avoids the warning. Fixes: 03c229906311 (cpufreq: pxa: make pxa_freqs arrays const) Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 4.2+ <stable@vger.kernel.org> # 4.2+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-28cpufreq: Use list_is_last() to check last entry of the policy listGautham R Shenoy1-3/+3
Currently next_policy() explicitly checks if a policy is the last policy in the cpufreq_policy_list. Use the standard list_is_last primitive instead. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-28cpufreq: Fix NULL reference crash while accessing policy->governor_dataViresh Kumar1-3/+8
There is a race discovered by Juri, where we are able to: - create and read a sysfs file before policy->governor_data is being set to a non NULL value. OR - set policy->governor_data to NULL, and reading a file before being destroyed. And so such a crash is reported: Unable to handle kernel NULL pointer dereference at virtual address 0000000c pgd = edfc8000 [0000000c] *pgd=bfc8c835 Internal error: Oops: 17 [#1] SMP ARM Modules linked in: CPU: 4 PID: 1730 Comm: cat Not tainted 4.5.0-rc1+ #463 Hardware name: ARM-Versatile Express task: ee8e8480 ti: ee930000 task.ti: ee930000 PC is at show_ignore_nice_load_gov_pol+0x24/0x34 LR is at show+0x4c/0x60 pc : [<c058f1bc>] lr : [<c058ae88>] psr: a0070013 sp : ee931dd0 ip : ee931de0 fp : ee931ddc r10: ee4bc290 r9 : 00001000 r8 : ef2cb000 r7 : ee4bc200 r6 : ef2cb000 r5 : c0af57b0 r4 : ee4bc2e0 r3 : 00000000 r2 : 00000000 r1 : c0928df4 r0 : ef2cb000 Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: adfc806a DAC: 00000051 Process cat (pid: 1730, stack limit = 0xee930210) Stack: (0xee931dd0 to 0xee932000) 1dc0: ee931dfc ee931de0 c058ae88 c058f1a4 1de0: edce3bc0 c07bfca4 edce3ac0 00001000 ee931e24 ee931e00 c01fcb90 c058ae48 1e00: 00000001 edce3bc0 00000000 00000001 ee931e50 ee8ff480 ee931e34 ee931e28 1e20: c01fb33c c01fcb0c ee931e8c ee931e38 c01a5210 c01fb314 ee931e9c ee931e48 1e40: 00000000 edce3bf0 befe4a00 ee931f78 00000000 00000000 000001e4 00000000 1e60: c00545a8 edce3ac0 00001000 00001000 befe4a00 ee931f78 00000000 00001000 1e80: ee931ed4 ee931e90 c01fbed8 c01a5038 ed085a58 00020000 00000000 00000000 1ea0: c0ad72e4 ee931f78 ee8ff488 ee8ff480 c077f3fc 00001000 befe4a00 ee931f78 1ec0: 00000000 00001000 ee931f44 ee931ed8 c017c328 c01fbdc4 00001000 00000000 1ee0: ee8ff480 00001000 ee931f44 ee931ef8 c017c65c c03deb10 ee931fac ee931f08 1f00: c0009270 c001f290 c0a8d968 ef2cb000 ef2cb000 ee8ff480 00000020 ee8ff480 1f20: ee8ff480 befe4a00 00001000 ee931f78 00000000 00000000 ee931f74 ee931f48 1f40: c017d1ec c017c2f8 c019c724 c019c684 ee8ff480 ee8ff480 00001000 befe4a00 1f60: 00000000 00000000 ee931fa4 ee931f78 c017d2a8 c017d160 00000000 00000000 1f80: 000a9f20 00001000 befe4a00 00000003 c000ffe4 ee930000 00000000 ee931fa8 1fa0: c000fe40 c017d264 000a9f20 00001000 00000003 befe4a00 00001000 00000000 Unable to handle kernel NULL pointer dereference at virtual address 0000000c 1fc0: 000a9f20 00001000 befe4a00 00000003 00000000 00000000 00000003 00000001 pgd = edfc4000 [0000000c] *pgd=bfcac835 1fe0: 00000000 befe49dc 000197f8 b6e35dfc 60070010 00000003 3065b49d 134ac2c9 [<c058f1bc>] (show_ignore_nice_load_gov_pol) from [<c058ae88>] (show+0x4c/0x60) [<c058ae88>] (show) from [<c01fcb90>] (sysfs_kf_seq_show+0x90/0xfc) [<c01fcb90>] (sysfs_kf_seq_show) from [<c01fb33c>] (kernfs_seq_show+0x34/0x38) [<c01fb33c>] (kernfs_seq_show) from [<c01a5210>] (seq_read+0x1e4/0x4e4) [<c01a5210>] (seq_read) from [<c01fbed8>] (kernfs_fop_read+0x120/0x1a0) [<c01fbed8>] (kernfs_fop_read) from [<c017c328>] (__vfs_read+0x3c/0xe0) [<c017c328>] (__vfs_read) from [<c017d1ec>] (vfs_read+0x98/0x104) [<c017d1ec>] (vfs_read) from [<c017d2a8>] (SyS_read+0x50/0x90) [<c017d2a8>] (SyS_read) from [<c000fe40>] (ret_fast_syscall+0x0/0x1c) Code: e5903044 e1a00001 e3081df4 e34c1092 (e593300c) ---[ end trace 5994b9a5111f35ee ]--- Fix that by making sure, policy->governor_data is updated at the right places only. Cc: 4.2+ <stable@vger.kernel.org> # 4.2+ Reported-and-tested-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-16Merge tag 'powerpc-4.5-1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Core: - Ground work for the new Power9 MMU from Aneesh Kumar K.V - Optimise FP/VMX/VSX context switching from Anton Blanchard Misc: - Various cleanups from Krzysztof Kozlowski, John Ogness, Rashmica Gupta, Russell Currey, Gavin Shan, Daniel Axtens, Michael Neuling, Andrew Donnellan - Allow wrapper to work on non-english system from Laurent Vivier - Add rN aliases to the pt_regs_offset table from Rashmica Gupta - Fix module autoload for rackmeter & axonram drivers from Luis de Bethencourt - Include KVM guest test in all interrupt vectors from Paul Mackerras - Fix DSCR inheritance over fork() from Anton Blanchard - Make value-returning atomics & {cmp}xchg* & their atomic_ versions fully ordered from Boqun Feng - Print MSR TM bits in oops messages from Michael Neuling - Add TM signal return & invalid stack selftests from Michael Neuling - Limit EPOW reset event warnings from Vipin K Parashar - Remove the Cell QPACE code from Rashmica Gupta - Append linux_banner to exception information in xmon from Rashmica Gupta - Add selftest to check if VSRs are corrupted from Rashmica Gupta - Remove broken GregorianDay() from Daniel Axtens - Import Anton's context_switch2 benchmark into selftests from Michael Ellerman - Add selftest script to test HMI functionality from Daniel Axtens - Remove obsolete OPAL v2 support from Stewart Smith - Make enter_rtas() private from Michael Ellerman - PPR exception cleanups from Michael Ellerman - Add page soft dirty tracking from Laurent Dufour - Add support for Nvlink NPUs from Alistair Popple - Add support for kexec on 476fpe from Alistair Popple - Enable kernel CPU dlpar from sysfs from Nathan Fontenot - Copy only required pieces of the mm_context_t to the paca from Michael Neuling - Add a kmsg_dumper that flushes OPAL console output on panic from Russell Currey - Implement save_stack_trace_regs() to enable kprobe stack tracing from Steven Rostedt - Add HWCAP bits for Power9 from Michael Ellerman - Fix _PAGE_PTE breaking swapoff from Aneesh Kumar K.V - Fix _PAGE_SWP_SOFT_DIRTY breaking swapoff from Hugh Dickins - scripts/recordmcount.pl: support data in text section on powerpc from Ulrich Weigand - Handle R_PPC64_ENTRY relocations in modules from Ulrich Weigand cxl: - cxl: Fix possible idr warning when contexts are released from Vaibhav Jain - cxl: use correct operator when writing pcie config space values from Andrew Donnellan - cxl: Fix DSI misses when the context owning task exits from Vaibhav Jain - cxl: fix build for GCC 4.6.x from Brian Norris - cxl: use -Werror only with CONFIG_PPC_WERROR from Brian Norris - cxl: Enable PCI device ID for future IBM CXL adapter from Uma Krishnan Freescale: - Freescale updates from Scott: Highlights include moving QE code out of arch/powerpc (to be shared with arm), device tree updates, and minor fixes" * tag 'powerpc-4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (149 commits) powerpc/module: Handle R_PPC64_ENTRY relocations scripts/recordmcount.pl: support data in text section on powerpc powerpc/powernv: Fix OPAL_CONSOLE_FLUSH prototype and usages powerpc/mm: fix _PAGE_SWP_SOFT_DIRTY breaking swapoff powerpc/mm: Fix _PAGE_PTE breaking swapoff cxl: Enable PCI device ID for future IBM CXL adapter cxl: use -Werror only with CONFIG_PPC_WERROR cxl: fix build for GCC 4.6.x powerpc: Add HWCAP bits for Power9 powerpc/powernv: Reserve PE#0 on NPU powerpc/powernv: Change NPU PE# assignment powerpc/powernv: Fix update of NVLink DMA mask powerpc/powernv: Remove misleading comment in pci.c powerpc: Implement save_stack_trace_regs() to enable kprobe stack tracing powerpc: Fix build break due to paca mm_context_t changes cxl: Fix DSI misses when the context owning task exits MAINTAINERS: Update Scott Wood's e-mail address powerpc/powernv: Fix minor off-by-one error in opal_mce_check_early_recovery() powerpc: Fix style of self-test config prompts powerpc/powernv: Only delay opal_rtc_read() retry when necessary ...
2016-01-05cpufreq-dt: fix handling regulator_get_voltage() resultAndrzej Hajda1-2/+3
The function can return negative values so it should be assigned to signed type. The problem has been detected using proposed semantic patch scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci. Link: http://permalink.gmane.org/gmane.linux.kernel/2038576 Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-05cpufreq: governor: Fix negative idle_time when configured with ↵Chen Yu1-0/+3
CONFIG_HZ_PERIODIC It is reported that, with CONFIG_HZ_PERIODIC=y cpu stays at the lowest frequency even if the usage goes to 100%, neither ondemand nor conservative governor works, however performance and userspace work as expected. If set with CONFIG_NO_HZ_FULL=y, everything goes well. This problem is caused by improper calculation of the idle_time when the load is extremely high(near 100%). Firstly, cpufreq_governor uses get_cpu_idle_time to get the total idle time for specific cpu, then: 1.If the system is configured with CONFIG_NO_HZ_FULL, the idle time is returned by ktime_get, which is always increasing, it's OK. 2.However, if the system is configured with CONFIG_HZ_PERIODIC, get_cpu_idle_time might not guarantee to be always increasing, because it will leverage get_cpu_idle_time_jiffy to calculate the idle_time, consider the following scenario: At T1: idle_tick_1 = total_tick_1 - user_tick_1 sample period(80ms)... At T2: ( T2 = T1 + 80ms): idle_tick_2 = total_tick_2 - user_tick_2 Currently the algorithm is using (idle_tick_2 - idle_tick_1) to get the delta idle_time during the past sample period, however it CAN NOT guarantee that idle_tick_2 >= idle_tick_1, especially when cpu load is high. (Yes, total_tick_2 >= total_tick_1, and user_tick_2 >= user_tick_1, but how about idle_tick_2 and idle_tick_1? No guarantee.) So governor might get a negative value of idle_time during the past sample period, which might mislead the system that the idle time is very big(converted to unsigned int), and the busy time is nearly zero, which causes the governor to always choose the lowest cpufreq, then cause this problem. In theory there are two solutions: 1.The logic should not rely on the idle tick during every sample period, but be based on the busy tick directly, as this is how 'top' is implemented. 2.Or the logic must make sure that the idle_time is strictly increasing during each sample period, then there would be no negative idle_time anymore. This solution requires minimum modification to current code and this patch uses method 2. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69821 Reported-by: Jan Fikar <j.fikar@gmail.com> Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-02cpufreq: mt8173: migrate to use operating-points-v2 bindingsPi-Cheng Chen1-6/+11
Modify mt8173-cpufreq driver to get OPP-sharing information and set up OPP table provided by operating-points-v2 bindings. Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-01cpufreq: Simplify core code related to boost supportRafael J. Wysocki2-18/+9
Notice that the boost_supported field in struct cpufreq_driver is redundant, because the driver's ->set_boost callback may be left unset if "boost" is not supported. Moreover, the only driver populating the ->set_boost callback is acpi_cpufreq, so make it avoid populating that callback if "boost" is not supported, rework the core to check ->set_boost instead of boost_supported to verify "boost" support and drop boost_supported which isn't used any more. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-01-01cpufreq: acpi-cpufreq: Simplify boost-related codeRafael J. Wysocki1-13/+8
The store_boost() routine is only used by store_cpb(), so move the code from it directly to that function and rename _store_boost() to set_boost() to make its name reflect the name of the driver callback pointing to it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-01-01cpufreq: Make cpufreq_boost_supported() staticRafael J. Wysocki1-6/+2
cpufreq_boost_supported() is not used outside of cpufreq.c, so make it static. While at it, refactor it as a one-liner (which it really is). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-12-28blackfin-cpufreq: Mark cpu_set_cclk() as staticMarkus Elfring1-1/+1
The cpu_set_cclk() function was only used in a single source file so far. Indicate this setting also by the corresponding linkage specifier. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-28blackfin-cpufreq: Change return type of cpu_set_cclk() to that of clk_set_rate()Markus Elfring1-1/+1
The return type "unsigned long" was used by the cpu_set_cclk() function while the type "int" is provided by the clk_set_rate() function. Let us make this usage consistent. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-28Merge back earlier cpufreq material for v4.5.Rafael J. Wysocki13-135/+673
2015-12-24cpufreq: scpi-cpufreq: signedness bug in scpi_get_dvfs_info()Dan Carpenter1-1/+1
The "domain" variable needs to be signed for the error handling to work. Fixes: 8def31034d03 (cpufreq: arm_big_little: add SCPI interface driver) Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-21Merge back earlier cpufreq material for v4.5.Rafael J. Wysocki13-135/+673
2015-12-17powerpc/powernv: remove FW_FEATURE_OPALv3 and just use FW_FEATURE_OPALStewart Smith1-1/+1
Long ago, only in the lab, there was OPALv1 and OPALv2. Now there is just OPALv3, with nobody ever expecting anything on pre-OPALv3 to be cared about or supported by mainline kernels. So, let's remove FW_FEATURE_OPALv3 and instead use FW_FEATURE_OPAL exclusively. Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-15Merge branches 'powercap', 'pm-cpufreq' and 'pm-domains'Rafael J. Wysocki2-2/+2
* powercap: powercap / RAPL: fix BIOS lock check * pm-cpufreq: cpufreq: intel_pstate: Minor cleanup for FRAC_BITS cpufreq: tegra: add regulator dependency for T124 * pm-domains: PM / Domains: Allow runtime PM callbacks to be re-used during system PM
2015-12-13Merge tag 'fixes-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC fixes from Arnd Bergmann: "Here are a bunch of small bug fixes for various ARM platforms, nothing really sticks out this week, most of either fixes bugs in code that was just added in 4.4, or that has been broken for many years without anyone noticing. at91/sama5d2: - fix sama5de hardware setup of sd/mmc interface - proper selection of pinctrl drivers. PIO4 is necessary for sama5d2 berlin: - fix incorrect clock input for SDIO exynos: - Fix potential NULL pointer dereference in Exynos PMU driver. imx: - Fix vf610 SAI clock configuration bug which is discovered by the newly added master mode support in SAI audio driver. - Fix buggy L2 cache latency values in vf610 device trees, which may cause system hang when cpu runs at a higher frequency. ixp4xx: - fix prototypes for readl/writel functions ls2080a: - use little-endian register access for GPIO and SDHCI omap: - Fix clock source for ARM TWD and global timers on am437x - Always select REGULATOR_FIXED_VOLTAGE for omap2+ instead of when MACH_OMAP3_PANDORA is selected - Fix SPI DMA handles for dm816x as only some were mapped - Fix up mbox cells for dm816x to make mailbox usable pxa: - use PWM lookup table for all ezx machines s3c24xx: - Remove incorrect __init annotation from s3c24xx cpufreq driver structures. versatile: - fix PCI IRQ mapping on Versatile PB" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ls2080a/dts: Add little endian property for GPIO IP block dt-bindings: define little-endian property for QorIQ GPIO ARM64: dts: ls2080a: fix eSDHC endianness ARM: dts: vf610: use reset values for L2 cache latencies ARM: pxa: use PWM lookup table for all machines ARM: dts: berlin: add 2nd clock for BG2Q sdhci0 and sdhci1 ARM: dts: berlin: correct BG2Q's sdhci2 2nd clock ARM: dts: am4372: fix clock source for arm twd and global timers ARM: at91: fix pinctrl driver selection ARM: at91/dt: add always-on to 1.8V regulator ARM: dts: vf610: fix clock definition for SAI2 ARM: imx: clk-vf610: fix SAI clock tree ARM: ixp4xx: fix read{b,w,l} return types irqchip/versatile-fpga: Fix PCI IRQ mapping on Versatile PB ARM: OMAP2+: enable REGULATOR_FIXED_VOLTAGE ARM: dts: add dm816x missing spi DT dma handles ARM: dts: add dm816x missing #mbox-cells cpufreq: s3c24xx: Do not mark s3c2410_plls_add as __init ARM: EXYNOS: Fix potential NULL pointer access in exynos_sys_powerdown_conf
2015-12-12cpufreq: st: Provide runtime initialised driver for ST's platformsLee Jones3-0/+305
The bootloader is charged with the responsibility to provide platform specific Dynamic Voltage and Frequency Scaling (DVFS) information via Device Tree. This driver takes the supplied configuration and registers it with the new generic OPP framework, to then be used with CPUFreq. Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-12cpufreq: intel_pstate: Minor cleanup for FRAC_BITSPrarit Bhargava1-1/+1
785ee27 ("cpufreq: intel_pstate: Fix limits->max_perf rounding error") hardcodes the value of FRAC_BITS. This patch fixes that minor issue. Fixes: 785ee2788141 (cpufreq: intel_pstate: Fix limits->max_perf rounding error) Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-12cpufreq: mt8173: Move resources allocation into ->probe()Pi-Cheng Chen1-24/+68
Since the return value of ->init() of cpufreq driver is not propagated to the device driver model now, move resources allocation into ->probe() to handle -EPROBE_DEFER properly. Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-12cpufreq: tegra: add regulator dependency for T124Arnd Bergmann1-1/+1
This driver is the only one that calls regulator_sync_voltage(), but it can currently be built with CONFIG_REGULATOR disabled, producing this build error: drivers/cpufreq/tegra124-cpufreq.c: In function 'tegra124_cpu_switch_to_pllx': drivers/cpufreq/tegra124-cpufreq.c:68:2: error: implicit declaration of function 'regulator_sync_voltage' [-Werror=implicit-function-declaration] regulator_sync_voltage(priv->vdd_cpu_reg); My first attempt was to implement a helper for this function for regulator_sync_voltage, but Mark Brown explained: We don't do this for *all* regulator API functions - there's some where using them strongly suggests that there is actually a dependency on the regulator API. This does seem like it might be falling into the specialist category [...] Looking at the code I'm pretty unclear on what the authors think the use of _sync_voltage() is doing in the first place so it may be even better to just remove the call. It seems to have been included in the first commit so there's not changelog explaining things and there's no comment either. I'd *expect* it to be a noop as far as I can see. This adds the dependency to make the driver always build successfully or not be enabled at all. Alternatively, we could investigate if the driver should stop calling regulator_sync_voltage instead. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-11Merge tag 'samsung-fixes-4.4' of ↵Arnd Bergmann1-1/+1
https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux into fixes Merge "Fixes for Exynos" from Krzysztof Kozlowski: 1. Fix potential NULL pointer dereference in Exynos PMU driver. 2. Remove incorrect __init annotation from s3c24xx cpufreq driver structures. * tag 'samsung-fixes-4.4' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux: cpufreq: s3c24xx: Do not mark s3c2410_plls_add as __init ARM: EXYNOS: Fix potential NULL pointer access in exynos_sys_powerdown_conf
2015-12-10cpufreq: intel_pstate: Account for IO wait timePhilippe Longepe1-3/+21
In cases where we have many IOs, the global load becomes low and the load algorithm will decrease the requested P-State. Because of that, the IOs overheads will increase and impact the IO performances. To improve IO bound work, we can count the io-wait time as busy time in calculating CPU busy. This change uses get_cpu_iowait_time_us() to obtain the IO wait time value and converts time into number of cycles spent waiting on IO at the TSC rate. At the moment, this trick is only used for Atom. Signed-off-by: Philippe Longepe <philippe.longepe@intel.com> Signed-off-by: Stephane Gasparini <stephane.gasparini@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-10cpufreq: intel_pstate: Account for non C0 timePhilippe Longepe1-5/+24
The current function to calculate cpu utilization uses the average P-state ratio (APerf/Mperf) scaled by the ratio of the current P-state to the max available non-turbo one. This leads to an overestimation of utilization which causes higher-performance P-states to be selected more often and that leads to increased energy consumption. This is a problem for low-power systems, so it is better to use a different utilization calculation algorithm for them. Namely, the Percent Busy value (or load) can be estimated as the ratio of the MPERF counter that runs at a constant rate only during active periods (C0) to the time stamp counter (TSC) that also runs (at the same rate) during idle. That is: Percent Busy = 100 * (delta_mperf / delta_tsc) Use this algorithm for platforms with SoCs based on the Airmont and Silvermont Atom cores. Signed-off-by: Philippe Longepe <philippe.longepe@intel.com> Signed-off-by: Stephane Gasparini <stephane.gasparini@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-10cpufreq: intel_pstate: Configurable algorithm to get target pstatePhilippe Longepe1-13/+17
Target systems using different cpus have different power and performance requirements. They may use different algorithms to get the next P-state based on their power or performance preference. For example, power-constrained systems may not want to use high-performance P-states as aggressively as a full-size desktop or a server platform. A server platform may want to run close to the max to achieve better performance, while laptop-like systems may prefer sacrificing performance for longer battery lifes. For the above reasons, modify intel_pstate to allow the target P-state selection algorithm to be depend on the CPU ID. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Philippe Longepe <philippe.longepe@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>