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2011-05-19Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, cpu: Fix detection of Celeron Covington stepping A1 and B0 Documentation, ABI: Update L3 cache index disable text x86, AMD, cacheinfo: Fix L3 cache index disable checks x86, AMD, cacheinfo: Fix fallout caused by max3 conversion x86, cpu: Change NOP selection for certain Intel CPUs x86, cpu: Clean up and unify the NOP selection infrastructure x86, percpu: Use ASM_NOP4 instead of hardcoding P6_NOP4 x86, cpu: Move AMD Elan Kconfig under "Processor family" Fix up trivial conflicts in alternative handling (commit dc326fca2b64 "x86, cpu: Clean up and unify the NOP selection infrastructure" removed some hacky 5-byte instruction stuff, while commit d430d3d7e646 "jump label: Introduce static_branch() interface" renamed HAVE_JUMP_LABEL to CONFIG_JUMP_LABEL in the code that went away)
2011-05-19[CPUFREQ] Move x86 drivers to drivers/cpufreq/Dave Jones
Signed-off-by: Dave Jones <davej@redhat.com>
2011-05-04[CPUFREQ] remove redundant sprintf from request_module call.Kees Cook
Since format string handling is part of request_module, there is no need to construct the module name. As such, drop the redundant sprintf and heap usage. Signed-off-by: Kees Cook <kees.cook@canonical.com> Signed-off-by: Dave Jones <davej@redhat.com>
2011-05-04[CPUFREQ] cpufreq_stats.c: Fixed brace coding style issueKarthigan Srinivasan
Fixed brace coding style issue. Signed-off-by: Karthigan Srinivasan <karthigan.srinivasan@hp.com> Signed-off-by: Dave Jones <davej@redhat.com>
2011-05-04[CPUFREQ] Fix memory leak in cpufreq_statsteven finney
When a CPU is taken offline in an SMP system, cpufreq_remove_dev() nulls out the per-cpu policy before cpufreq_stats_free_table() can make use of it. cpufreq_stats_free_table() then skips the call to sysfs_remove_group(), leaving about 100 bytes of sysfs-related memory unclaimed each time a CPU-removal occurs. Break up cpu_stats_free_table into sysfs and table portions, and call the sysfs portion early. Signed-off-by: Steven Finney <steven.finney@palm.com> Signed-off-by: Dave Jones <davej@redhat.com> Cc: stable@kernel.org
2011-05-04[CPUFREQ] use dynamic debug instead of custom infrastructureDominik Brodowski
With dynamic debug having gained the capability to report debug messages also during the boot process, it offers a far superior interface for debug messages than the custom cpufreq infrastructure. As a first step, remove the old cpufreq_debug_printk() function and replace it with a call to the generic pr_debug() function. How can dynamic debug be used on cpufreq? You need a kernel which has CONFIG_DYNAMIC_DEBUG enabled. To enabled debugging during runtime, mount debugfs and $ echo -n 'module cpufreq +p' > /sys/kernel/debug/dynamic_debug/control for debugging the complete "cpufreq" module. To achieve the same goal during boot, append ddebug_query="module cpufreq +p" as a boot parameter to the kernel of your choice. For more detailled instructions, please see Documentation/dynamic-debug-howto.txt Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
2011-05-04[CPUFREQ] CPU hotplug, re-create sysfs directory and symlinksJacob Shin
When we discover CPUs that are affected by each other's frequency/voltage transitions, the first CPU gets a sysfs directory created, and rest of the siblings get symlinks. Currently, when we hotplug off only the first CPU, all of the symlinks and the sysfs directory gets removed. Even though rest of the siblings are still online and functional, they are orphaned, and no longer governed by cpufreq. This patch, given the above scenario, creates a sysfs directory for the first sibling and symlinks for the rest of the siblings. Please note the recursive call, it was rather too ugly to roll it out. And the removal of redundant NULL setting (it is already taken care of near the top of the function). Signed-off-by: Jacob Shin <jacob.shin@amd.com> Acked-by: Mark Langsdorf <mark.langsdorf@amd.com> Reviewed-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> Cc: stable@kernel.org
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-23cpufreq: Use syscore_ops for boot CPU suspend/resume (v2)Rafael J. Wysocki
The cpufreq subsystem uses sysdev suspend and resume for executing cpufreq_suspend() and cpufreq_resume(), respectively, during system suspend, after interrupts have been switched off on the boot CPU, and during system resume, while interrupts are still off on the boot CPU. In both cases the other CPUs are off-line at the relevant point (either they have been switched off via CPU hotplug during suspend, or they haven't been switched on yet during resume). For this reason, although it may seem that cpufreq_suspend() and cpufreq_resume() are executed for all CPUs in the system, they are only called for the boot CPU in fact, which is quite confusing. To remove the confusion and to prepare for elimiating sysdev suspend and resume operations from the kernel enirely, convernt cpufreq to using a struct syscore_ops object for the boot CPU suspend and resume and rename the callbacks so that their names reflect their purpose. In addition, put some explanatory remarks into their kerneldoc comments. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-16[CPUFREQ] Remove the pm_message_t argument from driver suspendRafael J. Wysocki
None of the existing cpufreq drivers uses the second argument of its .suspend() callback (which isn't useful anyway), so remove it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Dave Jones <davej@redhat.com>
2011-03-16[CPUFREQ] Remove unneeded locksThomas Renninger
There cannot be any concurrent access to these through different cpu sysfs files anymore, because these tunables are now all global (not per cpu). I still have some doubts whether some of these locks were needed at all. Anyway, let's get rid of them. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> CC: cpufreq@vger.kernel.org
2011-03-16[CPUFREQ] Remove old, deprecated per cpu ondemand/conservative sysfs filesThomas Renninger
Marked deprecated for quite a whilte now... Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> CC: cpufreq@vger.kernel.org
2011-03-16[CPUFREQ] Remove deprecated sysfs file sampling_rate_maxThomas Renninger
Marked deprecated for quite a while now... Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> CC: cpufreq@vger.kernel.org
2011-03-16[CPUFREQ] calculate delay after dbs_check_cpuVincent Guittot
calculate ondemand delay after dbs_check_cpu call because it can modify rate_mult value use freq_lo_jiffies value for the sub sample period of powersave_bias mode Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Dave Jones <davej@redhat.com>
2011-03-16[CPUFREQ] drivers/cpufreq: Remove unnecessary semicolonsJoe Perches
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Dave Jones <davej@redhat.com>
2011-03-16Merge branch 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds
* 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: fix build failure introduced by s/freezeable/freezable/ workqueue: add system_freezeable_wq rds/ib: use system_wq instead of rds_ib_fmr_wq net/9p: replace p9_poll_task with a work net/9p: use system_wq instead of p9_mux_wq xfs: convert to alloc_workqueue() reiserfs: make commit_wq use the default concurrency level ocfs2: use system_wq instead of ocfs2_quota_wq ext4: convert to alloc_workqueue() scsi/scsi_tgt_lib: scsi_tgtd isn't used in memory reclaim path scsi/be2iscsi,qla2xxx: convert to alloc_workqueue() misc/iwmc3200top: use system_wq instead of dedicated workqueues i2o: use alloc_workqueue() instead of create_workqueue() acpi: kacpi*_wq don't need WQ_MEM_RECLAIM fs/aio: aio_wq isn't used in memory reclaim path input/tps6507x-ts: use system_wq instead of dedicated workqueue cpufreq: use system_wq instead of dedicated workqueues wireless/ipw2x00: use system_wq instead of dedicated workqueues arm/omap: use system_wq in mailbox workqueue: use WQ_MEM_RECLAIM instead of WQ_RESCUER
2011-03-01[CPUFREQ] fix BUG on cpufreq policy init failureJiri Slaby
cpufreq_register_driver sets cpufreq_driver to a structure owned (and placed) in the caller's memory. If cpufreq policy fails in its ->init function, sysdev_driver_register returns nonzero in cpufreq_register_driver. Now, cpufreq_register_driver returns an error without setting cpufreq_driver back to NULL. Usually cpufreq policy modules are unloaded because they propagate the error to the module init function and return that. So a later access to any member of cpufreq_driver causes bugs like: BUG: unable to handle kernel paging request at ffffffffa00270a0 IP: [<ffffffff8145eca3>] cpufreq_cpu_get+0x53/0xe0 PGD 1805067 PUD 1809063 PMD 1c3f90067 PTE 0 Oops: 0000 [#1] SMP last sysfs file: /sys/devices/virtual/net/tun0/statistics/collisions CPU 0 Modules linked in: ... Pid: 5677, comm: thunderbird-bin Tainted: G W 2.6.38-rc4-mm1_64+ #1389 To be filled by O.E.M./To Be Filled By O.E.M. RIP: 0010:[<ffffffff8145eca3>] [<ffffffff8145eca3>] cpufreq_cpu_get+0x53/0xe0 RSP: 0018:ffff8801aec37d98 EFLAGS: 00010086 RAX: 0000000000000202 RBX: 0000000000000000 RCX: 0000000000000001 RDX: ffffffffa00270a0 RSI: 0000000000001000 RDI: ffffffff8199ece8 ... Call Trace: [<ffffffff8145f490>] cpufreq_quick_get+0x10/0x30 [<ffffffff8103f12b>] show_cpuinfo+0x2ab/0x300 [<ffffffff81136292>] seq_read+0xf2/0x3f0 [<ffffffff8126c5d3>] ? __strncpy_from_user+0x33/0x60 [<ffffffff8116850d>] proc_reg_read+0x6d/0xa0 [<ffffffff81116e53>] vfs_read+0xc3/0x180 [<ffffffff81116f5c>] sys_read+0x4c/0x90 [<ffffffff81030dbb>] system_call_fastpath+0x16/0x1b ... It's all cause by weird fail path handling in cpufreq_register_driver. To fix that, shuffle the code to do proper handling with gotos. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Dave Jones <davej@redhat.com>
2011-01-26cpufreq: use system_wq instead of dedicated workqueuesTejun Heo
With cmwq, there's no reason for cpufreq drivers to use separate workqueues. Remove the dedicated workqueues from cpufreq_conservative and cpufreq_ondemand and use system_wq instead. The work items are already sync canceled on stop, so it's already guaranteed that no work is running on module exit. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Dave Jones <davej@redhat.com> Cc: cpufreq@vger.kernel.org
2011-01-20kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERTDavid Rientjes
The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option is used to configure any non-standard kernel with a much larger scope than only small devices. This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes references to the option throughout the kernel. A new CONFIG_EMBEDDED option is added that automatically selects CONFIG_EXPERT when enabled and can be used in the future to isolate options that should only be considered for embedded systems (RISC architectures, SLOB, etc). Calling the option "EXPERT" more accurately represents its intention: only expert users who understand the impact of the configuration changes they are making should enable it. Reviewed-by: Ingo Molnar <mingo@elte.hu> Acked-by: David Woodhouse <david.woodhouse@intel.com> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Greg KH <gregkh@suse.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jens Axboe <axboe@kernel.dk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Robin Holt <holt@sgi.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-04perf: Clean up power events by introducing new, more generic onesThomas Renninger
Add these new power trace events: power:cpu_idle power:cpu_frequency power:machine_suspend The old C-state/idle accounting events: power:power_start power:power_end Have now a replacement (but we are still keeping the old tracepoints for compatibility): power:cpu_idle and power:power_frequency is replaced with: power:cpu_frequency power:machine_suspend is newly introduced. Jean Pihet has a patch integrated into the generic layer (kernel/power/suspend.c) which will make use of it. the type= field got removed from both, it was never used and the type is differed by the event type itself. perf timechart userspace tool gets adjusted in a separate patch. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Jean Pihet <jean.pihet@newoldbits.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: rjw@sisk.pl LKML-Reference: <1294073445-14812-3-git-send-email-trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1290072314-31155-2-git-send-email-trenn@suse.de>
2010-10-22[CPUFREQ] add sampling_down_factor tunable to improve ondemand performanceDavid C Niemi
Adds a new global tunable, sampling_down_factor. Set to 1 it makes no changes from existing behavior, but set to greater than 1 (e.g. 100) it acts as a multiplier for the scheduling interval for reevaluating load when the CPU is at its top speed due to high load. This improves performance by reducing the overhead of load evaluation and helping the CPU stay at its top speed when truly busy, rather than shifting back and forth in speed. This tunable has no effect on behavior at lower speeds/lower CPU loads. This patch is against 2.6.36-rc6. This patch should help solve kernel bug 19672 "ondemand is slow". Signed-off-by: David Niemi <dniemi@verisign.com> Acked-by: Venkatesh Pallipadi <venki@google.com> CC: Daniel Hollocher <danielhollocher@gmail.com> CC: <cpufreq-list@vger.kernel.org> CC: <linux-kernel@vger.kernel.org> Signed-off-by: Dave Jones <davej@redhat.com>
2010-10-22[CPUFREQ] drivers/cpufreq: Adjust confusing if indentationJulia Lawall
Indent the body of for_each_cpu. The semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r disable braces4@ position p1,p2; statement S1,S2; @@ ( if (...) { ... } | if (...) S1@p1 S2@p2 ) @script:python@ p1 << r.p1; p2 << r.p2; @@ if (p1[0].column == p2[0].column): cocci.print_main("branch",p1) cocci.print_secs("after",p2) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] fix brace coding style issue.Neal Buckendahl
This patch fixes up a brace warning found by the checkpatch.pl tool Signed-off-by: Neal Buckendahl <nealb001@tbcnet.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] x86 cpufreq: Make trace_power_frequency cpufreq driver independentThomas Renninger
and fix the broken case if a core's frequency depends on others. trace_power_frequency was only implemented in a rather ungeneric way in acpi-cpufreq driver's target() function only. -> Move the call to trace_power_frequency to cpufreq.c:cpufreq_notify_transition() where CPUFREQ_POSTCHANGE notifier is triggered. This will support power frequency tracing by all cpufreq drivers trace_power_frequency did not trace frequency changes correctly when the userspace governor was used or when CPU cores' frequency depend on each other. -> Moving this into the CPUFREQ_POSTCHANGE notifier and pass the cpu which gets switched automatically fixes this. Robert Schoene provided some important fixes on top of my initial quick shot version which are integrated in this patch: - Forgot some changes in power_end trace (TP_printk/variable names) - Variable dummy in power_end must now be cpu_id - Use static 64 bit variable instead of unsigned int for cpu_id Signed-off-by: Thomas Renninger <trenn@suse.de> CC: davej@redhat.com CC: arjan@infradead.org CC: linux-kernel@vger.kernel.org CC: robert.schoene@tu-dresden.de Tested-by: robert.schoene@tu-dresden.de Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] ondemand: don't synchronize sample rate unless multiple cpus presentJocelyn Falempe
For UP systems this is not required, and results in a more consistent sample interval. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Jocelyn Falempe <jocelyn.falempe@motorola.com> Signed-off-by: Mike Chan <mike@android.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] unexport (un)lock_policy_rwsem* functionsAmerigo Wang
lock_policy_rwsem_* and unlock_policy_rwsem_* functions are scheduled to be unexported when 2.6.33. Now there are no other callers of them out of cpufreq.c, unexport them and make them static. Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] ondemand: Refactor frequency increase codeMike Chan
Make simpler to read and call. *** v3 - Always call when powersave_bias is enabled. Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Mike Chan <mike@android.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] fix memory leak in cpufreq_add_devXiaotian Feng
We didn't free policy->related_cpus in error path err_unlock_policy. This is catched by following kmemleak report: unreferenced object 0xffff88022a0b96d0 (size 512): comm "modprobe", pid 886, jiffies 4294689177 (age 780.694s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff8111ebe5>] create_object+0x186/0x281 [<ffffffff814fad4f>] kmemleak_alloc+0x60/0xa7 [<ffffffff8111127a>] kmem_cache_alloc_node_notrace+0x120/0x142 [<ffffffff81262e4f>] alloc_cpumask_var_node+0x2c/0xd7 [<ffffffff81262f0b>] alloc_cpumask_var+0x11/0x13 [<ffffffff81262f1c>] zalloc_cpumask_var+0xf/0x11 [<ffffffff8140fac0>] cpufreq_add_dev+0x11f/0x547 [<ffffffff81334bda>] sysdev_driver_register+0xc2/0x11d [<ffffffff8140e334>] cpufreq_register_driver+0xcb/0x1b8 [<ffffffffa032e040>] 0xffffffffa032e040 [<ffffffff810021ba>] do_one_initcall+0x5e/0x15c [<ffffffff81087f94>] sys_init_module+0xa6/0x1e6 [<ffffffff81009bc2>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] revert "[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call ↵Andrej Gelenberg
(second call site)" 395913d0b1db37092ea3d9d69b832183b1dd84c5 ("[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call (second call site)") is not needed, because there is no rwsem lock in cpufreq_ondemand and cpufreq_conservative anymore. Lock should not be released until the work done. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=1594 Signed-off-by: Andrej Gelenberg <andrej.gelenberg@udo.edu> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-05-18Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, hypervisor: add missing <linux/module.h> Modify the VMware balloon driver for the new x86_hyper API x86, hypervisor: Export the x86_hyper* symbols x86: Clean up the hypervisor layer x86, HyperV: fix up the license to mshyperv.c x86: Detect running on a Microsoft HyperV system x86, cpu: Make APERF/MPERF a normal table-driven flag x86, k8: Fix build error when K8_NB is disabled x86, cacheinfo: Disable index in all four subcaches x86, cacheinfo: Make L3 cache info per node x86, cacheinfo: Reorganize AMD L3 cache structure x86, cacheinfo: Turn off L3 cache index disable feature in virtualized environments x86, cacheinfo: Unify AMD L3 cache index disable checking cpufreq: Unify sysfs attribute definition macros powernow-k8: Fix frequency reporting x86, cpufreq: Add APERF/MPERF support for AMD processors x86: Unify APERF/MPERF support powernow-k8: Add core performance boost support x86, cpu: Add AMD core boosting feature flag to /proc/cpuinfo Fix up trivial conflicts in arch/x86/kernel/cpu/intel_cacheinfo.c and drivers/cpufreq/cpufreq_ondemand.c
2010-05-09ondemand: Make the iowait-is-busy time a sysfs tunableArjan van de Ven
Pavel Machek pointed out that not all CPUs have an efficient idle at high frequency. Specifically, older Intel and various AMD cpus would get a higher powerusage when copying files from USB. Mike Chan pointed out that the same is true for various ARM chips as well. Thomas Renninger suggested to make this a sysfs tunable with a reasonable default. This patch adds a sysfs tunable for the new behavior, and uses a very simple function to determine a reasonable default, depending on the CPU vendor/type. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: davej@redhat.com LKML-Reference: <20100509082651.46914d04@infradead.org> [ minor tidyup ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-09ondemand: Solve a big performance issue by counting IOWAIT time as busyArjan van de Ven
The ondemand cpufreq governor uses CPU busy time (e.g. not-idle time) as a measure for scaling the CPU frequency up or down. If the CPU is busy, the CPU frequency scales up, if it's idle, the CPU frequency scales down. Effectively, it uses the CPU busy time as proxy variable for the more nebulous "how critical is performance right now" question. This algorithm falls flat on its face in the light of workloads where you're alternatingly disk and CPU bound, such as the ever popular "git grep", but also things like startup of programs and maildir using email clients... much to the chagarin of Andrew Morton. This patch changes the ondemand algorithm to count iowait time as busy, not idle, time. As shown in the breakdown cases above, iowait is performance critical often, and by counting iowait, the proxy variable becomes a more accurate representation of the "how critical is performance" question. The problem and fix are both verified with the "perf timechar" tool. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Jones <davej@redhat.com> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20100509082606.3d9f00d0@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-08Merge commit 'v2.6.34-rc6' into x86/cpuH. Peter Anvin
2010-04-24Merge branch 'fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: [CPUFREQ] use max load in conservative governor [CPUFREQ] fix a lockdep warning
2010-04-09cpufreq: Unify sysfs attribute definition macrosBorislav Petkov
Multiple modules used to define those which are with identical functionality and were needlessly replicated among the different cpufreq drivers. Push them into the header and remove duplication. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> LKML-Reference: <1270065406-1814-7-git-send-email-bp@amd64.org> Reviewed-by: Thomas Renninger <trenn@suse.de> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-03-31[CPUFREQ] use max load in conservative governorDominik Brodowski
Instead of using the load of the last CPU in a package, use the maximum load of all CPUs in a package. Reported-by: Jean-Christian Goussard <jeanchristian.goussard@sfr.fr> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
2010-03-31[CPUFREQ] fix a lockdep warningAmerigo Wang
There is no need to do sysfs_remove_link() or kobject_put() etc. when policy_rwsem_write is held, move them after releasing the lock. This fixes the lockdep warning: halt/4071 is trying to acquire lock: (s_active){++++.+}, at: [<c0000000001ef868>] .sysfs_addrm_finish+0x58/0xc0 but task is already holding lock: (&per_cpu(cpu_policy_rwsem, cpu)){+.+.+.}, at: [<c0000000004cd6ac>] .lock_policy_rwsem_write+0x84/0xf4 Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-07Driver core: Constify struct sysfs_ops in struct kobj_typeEmese Revfy
Constify struct sysfs_ops. This is part of the ops structure constification effort started by Arjan van de Ven et al. Benefits of this constification: * prevents modification of data that is shared (referenced) by many other structure instances at runtime * detects/prevents accidental (but not intentional) modification attempts on archs that enforce read-only kernel data at runtime * potentially better optimized code as the compiler can assume that the const data cannot be changed * the compiler/linker move const data into .rodata and therefore exclude them from false sharing Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: David Teigland <teigland@redhat.com> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-13[CPUFREQ] Fix ondemand to not request targets outside policy limitsNagananda.Chumbalkar@hp.com
Dominik said: target_freq cannot be below policy->min or above policy->max. If it were, the whole cpufreq subsystem is broken. But (answer): I think the "ondemand" governor can ask for a target frequency that is below policy->min. ... A patch such as below may be needed to sanitize the target frequency requested by "ondemand". The "conservative" governor already has this check: Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> # diff -bur x/drivers/cpufreq/cpufreq_ondemand.c.orig y/drivers/cpufreq/cpufreq_ondemand.c
2009-12-14Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits) m68k: rename global variable vmalloc_end to m68k_vmalloc_end percpu: add missing per_cpu_ptr_to_phys() definition for UP percpu: Fix kdump failure if booted with percpu_alloc=page percpu: make misc percpu symbols unique percpu: make percpu symbols in ia64 unique percpu: make percpu symbols in powerpc unique percpu: make percpu symbols in x86 unique percpu: make percpu symbols in xen unique percpu: make percpu symbols in cpufreq unique percpu: make percpu symbols in oprofile unique percpu: make percpu symbols in tracer unique percpu: make percpu symbols under kernel/ and mm/ unique percpu: remove some sparse warnings percpu: make alloc_percpu() handle array types vmalloc: fix use of non-existent percpu variable in put_cpu_var() this_cpu: Use this_cpu_xx in trace_functions_graph.c this_cpu: Use this_cpu_xx for ftrace this_cpu: Use this_cpu_xx in nmi handling this_cpu: Use this_cpu operations in RCU this_cpu: Use this_cpu ops for VM statistics ... Fix up trivial (famous last words) global per-cpu naming conflicts in arch/x86/kvm/svm.c mm/slab.c
2009-11-24[ACPI/CPUFREQ] Introduce bios_limit per cpu cpufreq sysfs interfaceThomas Renninger
This interface is mainly intended (and implemented) for ACPI _PPC BIOS frequency limitations, but other cpufreq drivers can also use it for similar use-cases. Why is this needed: Currently it's not obvious why cpufreq got limited. People see cpufreq/scaling_max_freq reduced, but this could have happened by: - any userspace prog writing to scaling_max_freq - thermal limitations - hardware (_PPC in ACPI case) limitiations Therefore export bios_limit (in kHz) to: - Point the user that it's the BIOS (broken or intended) which limits frequency - Export it as a sysfs interface for userspace progs. While this was a rarely used feature on laptops, there will appear more and more server implemenations providing "Green IT" features like allowing the service processor to limit the frequency. People want to know about HW/BIOS frequency limitations. All ACPI P-state driven cpufreq drivers are covered with this patch: - powernow-k8 - powernow-k7 - acpi-cpufreq Tested with a patched DSDT which limits the first two cores (_PPC returns 1) via _PPC, exposed by bios_limit: # echo 2200000 >cpu2/cpufreq/scaling_max_freq # cat cpu*/cpufreq/scaling_max_freq 2600000 2600000 2200000 2200000 # #scaling_max_freq shows general user/thermal/BIOS limitations # cat cpu*/cpufreq/bios_limit 2600000 2600000 2800000 2800000 # #bios_limit only shows the HW/BIOS limitation CC: Pallipadi Venkatesh <venkatesh.pallipadi@intel.com> CC: Len Brown <lenb@kernel.org> CC: davej@codemonkey.org.uk CC: linux@dominikbrodowski.net Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-24[CPUFREQ] make internal cpufreq_add_dev_* staticAlex Chiang
No need to export these symbols; make them static. cpufreq_add_dev_policy cpufreq_add_dev_symlink cpufreq_add_dev_interface Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-24[CPUFREQ] Use global sysfs cpufreq structure for conservative governor tuningsThomas Renninger
Same adustments that have been added to the ondemand recently. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-17[CPUFREQ] Fix stale cpufreq_cpu_governor pointerPrarit Bhargava
Dave, Attached is an update of my patch against the cpufreq fixes branch. Before applying the patch I compiled and booted the tree to see if the panic was still there -- to my surprise it was not. This is because of the conversion of cpufreq_cpu_governor to a char[]. While the panic is kaput, the problem of stale data continues and my patch is still valid. It is possible to end up with the wrong governor after hotplug events because CPUFREQ_DEFAULT_GOVERNOR is statically linked to a default, while the cpu siblings may have had a different governor assigned by a user. ie) the patch is still needed in order to keep the governors assigned properly when hotplugging devices Signed-off-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-17[CPUFREQ] Resolve time unit thinko in ondemand/conservative govsPallipadi, Venkatesh
ondemand and conservative governors are messing up time units in the code path where NO_HZ is not enabled and ignore_nice is set. The walltime idletime stored is in jiffies and nice time calculation is happening in microseconds. The problem was reported and diagnosed by Alexander here. http://marc.info/?l=linux-kernel&m=125752550404513&w=2 The patch below fixes this thinko. Reported-by: Alexander Miller <Miller@fmi.uni-stuttgart.de> Tested-by: Alexander Miller <Miller@fmi.uni-stuttgart.de> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-17[CPUFREQ] Fix use after free on governor restoreDmitry Monakhov
Currently on governer backup/restore path we storing governor's pointer. This is wrong because one may unload governor's module after cpu goes offline. As result use-after-free will take place on restored cpu. It is not easy to exploit this bug, but still we have to close this issue ASAP. Issue was introduced by following commit 084f34939424161669467c19280dbcf637730314 ##TESTCASE## #!/bin/sh -x modprobe acpi_cpufreq # Any non default governor, in may case it is "ondemand" modprobe cpufreq_ondemand echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor rmmod acpi_cpufreq rmmod cpufreq_ondemand modprobe acpi_cpufreq # << use-after-free here. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Dave Jones <davej@redhat.com>
2009-10-29percpu: make percpu symbols in cpufreq uniqueTejun Heo
This patch updates percpu related symbols in cpufreq such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * drivers/cpufreq/cpufreq.c: s/policy_cpu/cpufreq_policy_cpu/ * drivers/cpufreq/freq_table.c: s/show_table/cpufreq_show_table/ * arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c: s/drv_data/acfreq_data/ s/old_perf/acfreq_old_perf/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
2009-09-18Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: [CPUFREQ] Fix NULL ptr regression in powernow-k8 [CPUFREQ] Create a blacklist for processors that should not load the acpi-cpufreq module. [CPUFREQ] Powernow-k8: Enable more than 2 low P-states [CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call (second call site) [CPUFREQ] ondemand - Use global sysfs dir for tuning settings [CPUFREQ] Introduce global, not per core: /sys/devices/system/cpu/cpufreq [CPUFREQ] Bail out of cpufreq_add_dev if the link for a managed CPU got created [CPUFREQ] Factor out policy setting from cpufreq_add_dev [CPUFREQ] Factor out interface creation from cpufreq_add_dev [CPUFREQ] Factor out symlink creation from cpufreq_add_dev [CPUFREQ] cleanup up -ENOMEM handling in cpufreq_add_dev [CPUFREQ] Reduce scope of cpu_sys_dev in cpufreq_add_dev [CPUFREQ] update Doc for cpuinfo_cur_freq and scaling_cur_freq
2009-09-15Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (46 commits) powerpc64: convert to dynamic percpu allocator sparc64: use embedding percpu first chunk allocator percpu: kill lpage first chunk allocator x86,percpu: use embedding for 64bit NUMA and page for 32bit NUMA percpu: update embedding first chunk allocator to handle sparse units percpu: use group information to allocate vmap areas sparsely vmalloc: implement pcpu_get_vm_areas() vmalloc: separate out insert_vmalloc_vm() percpu: add chunk->base_addr percpu: add pcpu_unit_offsets[] percpu: introduce pcpu_alloc_info and pcpu_group_info percpu: move pcpu_lpage_build_unit_map() and pcpul_lpage_dump_cfg() upward percpu: add @align to pcpu_fc_alloc_fn_t percpu: make @dyn_size mandatory for pcpu_setup_first_chunk() percpu: drop @static_size from first chunk allocators percpu: generalize first chunk allocator selection percpu: build first chunk allocators selectively percpu: rename 4k first chunk allocator to page percpu: improve boot messages percpu: fix pcpu_reclaim() locking ... Fix trivial conflict as by Tejun Heo in kernel/sched.c