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2014-06-10s390/cio: silence lockdep warningSebastian Ott1-0/+2
On systems where a ccw based console device is used a lockdep false alarm could be triggered when a device driver calls printk while holding a subchannels lock (e.g. in it's irq handler). Since this is valid behavior fix this by introducing a separate lock class for the console subchannels lock. The lockdep warning was revealed by "printk: enable interrupts before calling console_trylock_for_printk()" which changed console_unlock() to be called with lockdep enabled. [ INFO: possible recursive locking detected ] 3.15.0-rc5-next-20140520 #1 Not tainted --------------------------------------------- ccwgroup/2239 is trying to acquire lock: (&(sch->lock)->rlock){-.-...}, at: [<0000000000642a52>] raw3215_write+0x52/0x200 but task is already holding lock: (&(sch->lock)->rlock){-.-...}, at: [<00000000005fd160>] do_cio_interrupt+0x60/0x108 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(sch->lock)->rlock); lock(&(sch->lock)->rlock); *** DEADLOCK *** May be due to missing lock nesting notation 8 locks held by ccwgroup/2239: stack backtrace: CPU: 3 PID: 2239 Comm: ccwgroup Not tainted 3.15.0-rc5-next-20140520 #1 0000000036fab518 0000000036fab528 0000000000000002 0000000000000000 0000000036fab5b8 0000000036fab530 0000000036fab530 00000000001116e8 0000000000000000 0000000000986ec4 00000000009701b6 000000000000000b 0000000036fab578 0000000036fab518 0000000000000000 0000000000000000 0000000000000000 00000000001116e8 0000000036fab518 0000000036fab578 Call Trace: ([<0000000000111626>] show_trace+0x14e/0x158) [<000000000011169a>] show_stack+0x6a/0xe8 [<00000000007c6e72>] dump_stack+0x82/0xb0 [<00000000001a95f2>] validate_chain.isra.37+0xa4a/0xbb0 [<00000000001acaca>] __lock_acquire+0x4da/0xcd0 [<00000000001ada1a>] lock_acquire+0xba/0x218 [<00000000007cd634>] _raw_spin_lock_irqsave+0x6c/0xb8 [<0000000000642a52>] raw3215_write+0x52/0x200 [<0000000000643d16>] con3215_write+0x76/0xf8 [<00000000001bd87a>] call_console_drivers.constprop.25+0xfa/0x210 [<00000000001be0b0>] console_unlock+0x3e0/0x4e8 [<00000000001be450>] vprintk_emit+0x298/0x6e0 [<00000000005aa210>] dev_vprintk_emit+0xe0/0x1a8 [<00000000005aa320>] dev_printk_emit+0x48/0x50 [<00000000005aa390>] __dev_printk+0x68/0xb0 [<00000000005aa7c2>] _dev_info+0x62/0x70 [<0000000000657bf0>] qeth_l2_send_setmac_cb+0xd0/0x190 [<0000000000651a1e>] qeth_send_control_data_cb+0x3a6/0x6a8 [<0000000000655546>] qeth_irq+0x1a6/0xac0 [<000000000060a0ac>] ccw_device_call_handler+0xa4/0xc0 [<0000000000608b62>] ccw_device_irq+0x5a/0x190 [<00000000005fd1ca>] do_cio_interrupt+0xca/0x108 [<00000000001c0a2e>] handle_irq_event_percpu+0x5e/0x378 [<00000000001c46fc>] handle_percpu_irq+0x6c/0x98 [<00000000001c0066>] generic_handle_irq+0x46/0x68 [<000000000010b5b6>] do_IRQ+0x5e/0x88 [<00000000007cf304>] io_call+0x6/0x20 [<000000000064c63a>] qeth_send_control_data+0x322/0x570 ([<000000000064c50e>] qeth_send_control_data+0x1f6/0x570) [<0000000000651db2>] qeth_send_ipa_cmd+0x92/0x120 [<000000000065b310>] __qeth_l2_set_online+0x170/0xaa8 [<000000000060ebb6>] ccwgroup_set_online+0x56/0x90 [<000000000060ef96>] ccwgroup_online_store+0xd6/0xe0 [<000000000033d11a>] kernfs_fop_write+0x10a/0x188 [<00000000002bbd00>] vfs_write+0x98/0x1c0 [<00000000002bc8a0>] SyS_write+0x60/0xd0 [<00000000007cee3a>] sysc_nr_ok+0x22/0x28 [<000003fffd0c3f28>] 0x3fffd0c3f28 Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-05-28s390/lowcore: replace lowcore irb array with a per-cpu variableMartin Schwidefsky1-3/+6
Remove the 96-byte irb array from the lowcore and create a per-cpu variable instead. That way we will pick up any change in the definition of the struct irb automatically. Acked-By: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-04-01Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-4/+2
Pull irq code updates from Thomas Gleixner: "The irq department proudly presents: - Another tree wide sweep of irq infrastructure abuse. Clear winner of the trainwreck engineering contest was: #include "../../../kernel/irq/settings.h" - Tree wide update of irq_set_affinity() callbacks which miss a cpu online check when picking a single cpu out of the affinity mask. - Tree wide consolidation of interrupt statistics. - Updates to the threaded interrupt infrastructure to allow explicit wakeup of the interrupt thread and a variant of synchronize_irq() which synchronizes only the hard interrupt handler. Both are needed to replace the homebrewn thread handling in the mmc/sdhci code. - New irq chip callbacks to allow proper support for GPIO based irqs. The GPIO based interrupts need to request/release GPIO resources from request/free_irq. - A few new ARM interrupt chips. No revolutionary new hardware, just differently wreckaged variations of the scheme. - Small improvments, cleanups and updates all over the place" I was hoping that that trainwreck engineering contest was a April Fools' joke. But no. * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (68 commits) irqchip: sun7i/sun6i: Disable NMI before registering the handler ARM: sun7i/sun6i: dts: Fix IRQ number for sun6i NMI controller ARM: sun7i/sun6i: irqchip: Update the documentation ARM: sun7i/sun6i: dts: Add NMI irqchip support ARM: sun7i/sun6i: irqchip: Add irqchip driver for NMI controller genirq: Export symbol no_action() arm: omap: Fix typo in ams-delta-fiq.c m68k: atari: Fix the last kernel_stat.h fallout irqchip: sun4i: Simplify sun4i_irq_ack irqchip: sun4i: Use handle_fasteoi_irq for all interrupts genirq: procfs: Make smp_affinity values go+r softirq: Add linux/irq.h to make it compile again m68k: amiga: Add linux/irq.h to make it compile again irqchip: sun4i: Don't ack IRQs > 0, fix acking of IRQ 0 irqchip: sun4i: Fix a comment about mask register initialization irqchip: sun4i: Fix irq 0 not working genirq: Add a new IRQCHIP_EOI_THREADED flag genirq: Document IRQCHIP_ONESHOT_SAFE flag ARM: sunxi: dt: Convert to the new irq controller compatibles irqchip: sunxi: Change compatibles ...
2014-04-01Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+1
Pull timer updates from Ingo Molnar: "The main purpose is to fix a full dynticks bug related to virtualization, where steal time accounting appears to be zero in /proc/stat even after a few seconds of competing guests running busy loops in a same host CPU. It's not a regression though as it was there since the beginning. The other commits are preparatory work to fix the bug and various cleanups" * 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arch: Remove stub cputime.h headers sched: Remove needless round trip nsecs <-> tick conversion of steal time cputime: Fix jiffies based cputime assumption on steal accounting cputime: Bring cputime -> nsecs conversion cputime: Default implementation of nsecs -> cputime conversion cputime: Fix nsecs_to_cputime() return type cast
2014-03-13cputime: Default implementation of nsecs -> cputime conversionFrederic Weisbecker1-1/+1
The architectures that override cputime_t (s390, ppc) don't provide any version of nsecs_to_cputime(). Indeed this cputime_t implementation by backend only happens when CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y under which the core code doesn't make any use of nsecs_to_cputime(). At least for now. We are going to make a broader use of it so lets provide a default version with a per usecs granularity. It should be good enough for most usecases. Cc: Ingo Molnar <mingo@kernel.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-03-04s390: Do not rely on magic indirect includesThomas Gleixner1-0/+1
commit: 8f945a33 (genirq: Move kstat_incr_irqs_this_cpu() to core) unearthed the following: arch/s390/kernel/irq.c: In function 'init_IRQ': >> arch/s390/kernel/irq.c:93:2: error: implicit declaration of function 'irq_reserve_irqs' [-Werror=implicit-function-declaration] .... cc1: some warnings being treated as errors -- drivers/s390/cio/cio.c: In function 'init_cio_interrupts': >> drivers/s390/cio/cio.c:594:2: error: implicit declaration of function 'irq_set_chip_and_handler' [-Werror=implicit-function-declaration] [-Werror=implicit-function-declaration] .... cc1: some warnings being treated as errors The reason is that those files require linux/irq.h and magically pulled that in via linux/kernel_stat.h The commit above got rid of the pointless include of linux/irq.h in linux/kernel_stat.h and therefor broke the build. Include linux/irq.h Reported-by: fengguang.wu@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: s390 <linux-s390@vger.kernel.org>
2014-03-04s390: Cio: Use the core irq stats functionThomas Gleixner1-4/+1
Let the core do the irq_desc resolution. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: s390 <linux-s390@vger.kernel.org> Link: http://lkml.kernel.org/r/20140223212737.983433636@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-21s390: improve debug feature usageSebastian Ott1-2/+2
The maximum usable buffer size of the s390 debug feature (when using the sprintf_view) is 11 * sizeof(long) (1 pointer for the format string + 10 arguments). When a larger buffer size is specified the additional memory is unused and wasted per debug entry. So reducing the buffer size to its maximum (or to the actual buffer size used) will make more precious debug feature space usable. For pci_msg, chsc_msg, and cio_crw we use the additional usable dbf space to reduce the number of allocated pages. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-06s390/cio: improve cio_commit_configSebastian Ott1-26/+14
The modify subchannel wrapper cio_commit_config can fail when (unexpected) status is pending on the subchannel. Callers of cio_commit_config (that operated on enabled subchannels) needed to do error handling for that case (clear the unexpected status with test subchannel and retry). This error handling is missing in some code paths and caused online setting of devices to fail. Fix this for all callers by moving the error handling inside cio_commit_config. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-22s390/time: correct use of store clock fastMartin Schwidefsky1-2/+2
The result of the store-clock-fast (STCKF) instruction is a bit fuzzy. It can happen that the value stored on one CPU is smaller than the value stored on another CPU, although the order of the stores is the other way around. This can cause deltas of get_tod_clock() values to become negative when they should not be. We need to be more careful with store-clock-fast, this patch partially reverts git commit e4b7b4238e666682555461fa52eecd74652f36bb "time: always use stckf instead of stck if available". The get_tod_clock() function now uses the store-clock-extended (STCKE) instruction. get_tod_clock_fast() can be used if the fuzziness of store-clock-fast is acceptable e.g. for wait loops local to a CPU. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22s390: convert interrupt handling to use generic hardirqMartin Schwidefsky1-23/+23
With the introduction of PCI it became apparent that s390 should convert to generic hardirqs as too many drivers do not have the correct dependency for GENERIC_HARDIRQS. On the architecture level s390 does not have irq lines. It has external interrupts, I/O interrupts and adapter interrupts. This patch hard-codes all external interrupts as irq #1, all I/O interrupts as irq #2 and all adapter interrupts as irq #3. The additional information from the lowcore associated with the interrupt is stored in the pt_regs of the interrupt frame, where the interrupt handler can pick it up. For PCI/MSI interrupts the adapter interrupt handler scans the relevant bit fields and calls generic_handle_irq with the virtual irq number for the MSI interrupt. Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-06-26s390/irq: store interrupt information in pt_regsMartin Schwidefsky1-40/+28
Copy the interrupt parameters from the lowcore to the pt_regs structure in entry[64].S and reduce the arguments of the low level interrupt handler to the pt_regs pointer only. In addition move the test-pending-interrupt loop from do_IRQ to entry[64].S to make sure that interrupt information is always delivered via pt_regs. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-26s390/cio: fix irq statisticsSebastian Ott1-0/+1
When we fetch an interrupt on the CCW console using tsch (via ccw_device_wait_idle formerly known as wait_cons_dev) we increment the irq count for the affected interruption class but it is not accounted as an IO interrupt. This is broken since commit b603d258a43b4e7339660bdd3b5c25eacd603e54 "s390: remove superfluous tpi from wait_cons_dev" Fix it so that the sum of the individual interrupts per class matches the number of IO interrupts again. Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-17s390/css: move subchannel lock allocationSebastian Ott1-25/+4
cio_validate_subchannel is used to do some basic checks to find out if it's worth to further investigate a subchannel. Move the allocation and initialization of the subchannels locks to css_alloc_subchannel. Clean up the functions involved while at it. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-17s390/css: introduce cio_register_early_subchannelsSebastian Ott1-2/+9
Use cio_register_early_subchannels to register early subchannels which are already in use. Call this function before we do the actual subchannel scanning loop. This helps us to get rid of some more special cases regarding the console subchannel. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-17s390/cio: get rid of static console subchannelSebastian Ott1-77/+34
Remove the static console subchannel (and friends) and use dynamic allocation for these structures. With this change the console subchanel is treated (mostly) like any other subchannel and we can remove some special cases. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-17s390/cio: wait_cons_dev don't use static variableSebastian Ott1-18/+2
wait_cons_dev is used to busy wait for an interrupt on the console ccw device. Stop using the static console_subchannel and add a parameter to this function to specify on which ccw device/subchannel we have to do the polling. While at it rename the function to ccw_device_wait_idle and move it to device.c Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-02-14s390/time: rename tod clock access functionsHeiko Carstens1-2/+2
Fix name clash with some common code device drivers and add "tod" to all tod clock access function names. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-01-08s390/irq: remove split irq fields from /proc/statHeiko Carstens1-4/+4
Now that irq sum accounting for /proc/stat's "intr" line works again we have the oddity that the sum field (first field) contains only the sum of the second (external irqs) and third field (I/O interrupts). The reason for that is that these two fields are already sums of all other fields. So if we would sum up everything we would count every interrupt twice. This is broken since the split interrupt accounting was merged two years ago: 052ff461c8427629aee887ccc27478fc7373237c "[S390] irq: have detailed statistics for interrupt types". To fix this remove the split interrupt fields from /proc/stat's "intr" line again and only have them in /proc/interrupts. This restores the old behaviour, seems to be the only sane fix and mimics a behaviour from other architectures where /proc/interrupts also contains more than /proc/stat's "intr" line does. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-01-08s390/irq: enable irq sum accounting for /proc/stat againHeiko Carstens1-1/+1
For more than two years, since f2c66cd8eeddedb440f33bc0f5cec1ed7ae376cb "/proc/stat: scalability of irq num per cpu" the output of /proc/stat is broken. The first field in the "intr" line should contain the sum of all interrupts, however since the above mentioned change it is always zero. The reason for that is that a per cpu irq sum variable had been introduced which got incremented when calling kstat_incr_irqs_this_cpu(). However on s390 we directly incremented only the per cpu per irq counter by accessing the array element via kstat_cpu(smp_processor_id()).irqs[...]. So fix this and use the kstat_incr_irqs_this_cpu() wrapper which increments both: the per cpu per irq counter and the per cpu irq sum counter. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26s390: add uninitialized_var() to suppress false positive compiler warningsHeiko Carstens1-1/+1
Get rid of these: arch/s390/kernel/smp.c:134:19: warning: ‘status’ may be used uninitialized in this function [-Wuninitialized] arch/s390/mm/pgtable.c:641:10: warning: ‘table’ may be used uninitialized in this function [-Wuninitialized] arch/s390/mm/pgtable.c:644:12: warning: ‘page’ may be used uninitialized in this function [-Wuninitialized] drivers/s390/cio/cio.c:1037:14: warning: ‘schid’ may be used uninitialized in this function [-Wuninitialized] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-07-20s390/comments: unify copyright messages and remove file namesHeiko Carstens1-2/+1
Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-05-16s390: remove superfluous tpi from wait_cons_devMartin Schwidefsky1-54/+19
wait_cons_dev waits for a particular subchannel to complete an I/O. It is not necessary to use tpi to get the subchannel id as it is already known. This avoids changes to the interrupt subclass mask and allows to remove the lock & unlock of the subchannel lock. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11[S390] rework idle codeMartin Schwidefsky1-2/+0
Whenever the cpu loads an enabled wait PSW it will appear as idle to the underlying host system. The code in default_idle calls vtime_stop_cpu which does the necessary voodoo to get the cpu time accounting right. The udelay code just loads an enabled wait PSW. To correct this rework the vtime_stop_cpu/vtime_start_cpu logic and move the difficult parts to entry[64].S, vtime_stop_cpu can now be called from anywhere and vtime_start_cpu is gone. The correction of the cpu time during wakeup from an enabled wait PSW is done with a critical section in entry[64].S. As vtime_start_cpu is gone, s390_idle_check can be removed as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30[S390] kdump backend codeMichael Holzheu1-1/+1
This patch provides the architecture specific part of the s390 kdump support. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30[S390] fix mismatch in summation of I/O IRQ statisticsPeter Oberparleiter1-3/+14
Current IRQ statistics support does not show detail counts for I/O interrupts which are processed internally only. The result is a summation count which is way off such as this one: CPU0 CPU1 CPU2 I/O: 1331 710 442 [...] QAI: 15 16 16 [I/O] QDIO Adapter Interrupt QDI: 1 0 0 [I/O] QDIO Interrupt DAS: 706 645 381 [I/O] DASD C15: 26 10 0 [I/O] 3215 C70: 0 0 0 [I/O] 3270 TAP: 0 0 0 [I/O] Tape VMR: 0 0 0 [I/O] Unit Record Devices LCS: 0 0 0 [I/O] LCS CLW: 0 0 0 [I/O] CLAW CTC: 0 0 0 [I/O] CTC APB: 0 0 0 [I/O] AP Bus Fix this by moving I/O interrupt accounting into the common I/O layer. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-09-26[S390] cio: fix cio_tpi ignoring adapter interruptsPeter Oberparleiter1-2/+6
Ensure that adapter interrupts are correctly processed when they are retrieved using TEST PENDING INTERRUPTION. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-03-15[S390] cio: move options to io_sch_privateSebastian Ott1-26/+11
Move the options member from struct subchannel to io_subchannel_private since it's I/O subchannel specific. Also remove the unused cio_get_options function. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-03-15[S390] remove superfluous check from do_IRQSebastian Ott1-5/+1
Don't check for the int_type if an adapter interrupt is presented. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-12-17drivers: Replace __get_cpu_var with __this_cpu_read if not used for an address.Christoph Lameter1-1/+1
__get_cpu_var() can be replaced with this_cpu_read and will then use a single read instruction with implied address calculation to access the correct per cpu instance. However, the address of a per cpu variable passed to __this_cpu_read() cannot be determed (since its an implied address conversion through segment prefixes). Therefore apply this only to uses of __get_cpu_var where the addres of the variable is not used. V3->V4: - Move one instance of this_cpu_inc_return to a later patch so that this one can go in without percpu infrastructrure changes. Sedat: fixed compile failure caused by an extra ')'. Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2010-05-17[S390] idle time accounting vs. machine checksMartin Schwidefsky1-1/+2
A machine check can interrupt the i/o and external interrupt handler anytime. If the machine check occurs while the interrupt handler is waking up from idle vtime_start_cpu can get executed a second time and the int_clock / async_enter_timer values in the lowcore get clobbered. This can confuse the cpu time accounting. To fix this problem two changes are needed. First the machine check handler has to use its own copies of int_clock and async_enter_timer, named mcck_clock and mcck_enter_timer. Second the nested execution of vtime_start_cpu has to be prevented. This is done in s390_idle_check by checking the wait bit in the program status word. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-04-22[S390] cio: use exception-save stschSebastian Ott1-9/+9
Using stsch on schids with ssid != 0 can lead to an operand exception. Use stsch_err to handle potential exceptions if we fail to reenable mss after hibernation. Cc: <stable@kernel.org> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26[S390] Cleanup struct _lowcore usage and defines.Heiko Carstens1-6/+6
Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26[S390] add MACHINE_IS_LPAR flagMartin Schwidefsky1-1/+1
Introduce the MACHINE_IS_LPAR flag for code that should only be executed if Linux is running in an LPAR. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-11-05nohz: Introduce arch_needs_cpuMartin Schwidefsky1-0/+1
Allow the architecture to request a normal jiffy tick when the system goes idle and tick_nohz_stop_sched_tick is called . On s390 the hook is used to prevent the system going fully idle if there has been an interrupt other than a clock comparator interrupt since the last wakeup. On s390 the HiperSockets response time for 1 connection ping-pong goes down from 42 to 34 microseconds. The CPU cost decreases by 27%. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> LKML-Reference: <20090929122533.402715150@de.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-09-11[S390] cio: remove subchannel init_nameSebastian Ott1-7/+0
We used the init_name to set the console subchannels name early at the boot stage. With the patch cio: fix memleak in subchannel validation we moved the name setting to the point where we actually register the console subchannel. At this time we can do dynamic allocations and therefore use dev_set_name. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: fix memleak in subchannel validationSebastian Ott1-5/+0
When scanning for new subchannels we have a code path where we allocate memory for a struct subchannel, set the device name (which is dynamically allocated now) and do a check if the underlying device is blacklisted - if so we free the subchannel structure. Since we have not set up refcounting at this stage, the device name's memory is lost. Fix this by moving the dev_set_name after the blacklist test. Note: With this patch the init_name for the console subchannel becomes virtually obsolete. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: increase trace levelSebastian Ott1-29/+15
Move debug traces for start I/O and interrupt events to exclusive trace levels. Also change tracing in hot-path from sprintf (costly) to hex. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] ftrace: add function graph tracer supportHeiko Carstens1-2/+2
Function graph tracer support for s390. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] merge cpu.h into cputime.hMartin Schwidefsky1-1/+1
All definition in cpu.h have to do with cputime accounting. Move them to cputime.h and remove the header file. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: Try harder to disable subchannel.Cornelia Huck1-8/+10
Acting upon the assumption that cio_disable_subchannel() is only called when we really want to disable the subchannel (a) remove the check for activity (it is already done in ccw_device_offline(), which is the place where it matters) (b) collect pending status via tsch() and ignore it (it can't matter anymore since the subchannel will be disabled). Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] split/move machine check handler codeHeiko Carstens1-1/+2
Split machine check handler code and move it to cio and kernel code where it belongs to. No functional change. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-01-08fix similar typos to successfullColy Li1-1/+1
When I review ocfs2 code, find there are 2 typos to "successfull". After doing grep "successfull " in kernel tree, 22 typos found totally -- great minds always think alike :) This patch fixes all the similar typos. Thanks for Randy's ack and comments. Signed-off-by: Coly Li <coyli@suse.de> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: Jeff Garzik <jeff@garzik.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Vlad Yasevich <vladislav.yasevich@hp.com> Cc: Sridhar Samudrala <sri@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-31[PATCH] improve idle cputime accountingMartin Schwidefsky1-1/+1
Distinguish the cputime of the idle process where idle is actually using cpu cycles from the cputime where idle is sleeping on an enabled wait psw. The former is accounted as system time, the later as idle time. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] convert cio printks to pr_xxx macros.Michael Ernst1-1/+4
Signed-off-by: Michael Ernst <mernst@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: introduce cio_commit_configSebastian Ott1-61/+73
To change the configuration of a subchannel we alter the modifiable bits of the subchannel's schib field and issue a modify subchannel. There can be the case that not all changes were applied -or worse- quietly overwritten by the hardware. With the next store subchannel we obtain the current state of the hardware but lose our target configuration. With this patch we introduce a subchannel_config structure which contains the target subchannel configuration. Additionally the msch wrapper cio_modify is replaced with cio_commit_config which copies the desired changes to a temporary schib. msch is then called with the temporary schib. This schib is only written back to the subchannel if all changes were applied. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: introduce cio_update_schibSebastian Ott1-12/+35
There is the chance that we get condition code 0 for a stsch but the resulting schib is not vaild. In the current code there are 2 cases: * we do a check for validity of the schib after stsch, but at this time we have already stored the invaild schib in the subchannel structure. This may lead to problems. * we don't do a check for validity, which is not that good either. The patch addresses both issues by introducing the stsch wrapper cio_update_schib which performs stsch on a local schib. This schib is only written back to the subchannel if it's valid. side note: For some functions (chp_events) the return codes are different now (-ENXIO vs -ENODEV) but this shouldn't do harm since the caller doesn't check for _specific_ errors. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: get rid of compile warningHeiko Carstens1-38/+37
Move cio_tpi() to the rest of the CONFIG_CCW_CONSOLE functions to get rid of this one: drivers/s390/cio/cio.c:115: warning: 'cio_tpi' defined but not used Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-10[S390] Move private simple udelay function to arch/s390/lib/delay.c.Heiko Carstens1-15/+2
Move cio's private simple udelay function to lib/delay.c and turn it into something much more readable. So we have all implementations at one place. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-10[S390] cio: fix cio_tpi.Heiko Carstens1-2/+6
In cio_tpi only disable bottom halves when not in interrupt context. Otherwise a WARN_ON gets triggered. Besides that, when we are in interrupt context bottom halves are disabled anyway. Fixes this one: Badness at kernel/softirq.c:77 Modules linked in: CPU: 2 Not tainted 2.6.26 #4 Process swapper (pid: 0, task: 000000003fe83db0, ksp: 000000003fea7d28) Krnl PSW : 0404c00180000000 0000000000053f4e (__local_bh_disable+0xbe/0xcc) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3 Krnl GPRS: 0000000000008ee0 00000000005f95e0 0000000000000000 0000000000000001 000000000020be92 0000000000000000 0000000000000210 00000000005d36c0 000000003fb5f4d8 0000000000000000 000000000020bed0 000000003fb5f3c8 00000000009be920 0000000000364898 000000003fb5f408 000000003fb5f3c8 Krnl Code: 0000000000053f42: bf2f1000 icm %r2,15,0(%r1) 0000000000053f46: a774ffc5 brc 7,53ed0 0000000000053f4a: a7f40001 brc 15,53f4c >0000000000053f4e: a7280001 lhi %r2,1 0000000000053f52: 50201000 st %r2,0(%r1) 0000000000053f56: a7f4ffbd brc 15,53ed0 0000000000053f5a: 0707 bcr 0,%r7 0000000000053f5c: a7f13fc0 tmll %r15,16320 Call Trace: ([<0000000000000210>] 0x210) [<0000000000053f86>] local_bh_disable+0x2a/0x38 [<000000000020bed0>] wait_cons_dev+0xd4/0x154 [<0000000000247cb2>] raw3215_make_room+0x6a/0x1a8 [<000000000024861a>] raw3215_write+0x86/0x28c [<00000000002488a0>] con3215_write+0x80/0x110 [<000000000004c3e0>] __call_console_drivers+0xc8/0xe4 [<000000000004c47e>] _call_console_drivers+0x82/0xc4 [<000000000004c744>] release_console_sem+0x218/0x2c0 [<000000000004cf64>] vprintk+0x3c0/0x504 [<0000000000354a4a>] printk+0x52/0x64 [<0000000000088004>] __print_symbol+0x40/0x50 [<0000000000071dbc>] print_stack_trace+0x78/0xac [<0000000000079e78>] print_lock_dependencies+0x148/0x208 [<000000000007a050>] print_irq_inversion_bug+0x118/0x15c [<000000000007a106>] check_usage_forwards+0x72/0x84 [<000000000007a36e>] mark_lock+0x1d2/0x594 [<000000000007baca>] __lock_acquire+0x886/0xf48 [<000000000007c234>] lock_acquire+0xa8/0xe0 [<0000000000350316>] _write_lock+0x56/0x98 [<000000000026cd92>] zfcp_erp_adapter_reopen+0x4e/0x8c [<000000000026f1e8>] zfcp_qdio_int_resp+0x2e4/0x2f4 [<00000000002210f4>] qdio_int_handler+0x274/0x888 [<00000000002177b6>] ccw_device_call_handler+0x6e/0xd8 [<0000000000215336>] ccw_device_irq+0xd6/0x160 [<0000000000212f88>] io_subchannel_irq+0x8c/0x118 [<000000000020c120>] do_IRQ+0x1d0/0x1fc [<00000000000270b2>] io_return+0x0/0x8 [<000000000001c8a4>] cpu_idle+0x178/0x21c ([<000000000001c884>] cpu_idle+0x158/0x21c) [<00000000003483a2>] start_secondary+0xb6/0xc8 INFO: lockdep is turned off. Last Breaking-Event-Address: [<0000000000053f4a>] __local_bh_disable+0xba/0xcc Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>