linux-dev/drivers/s390/cio/qdio_debug.c, branch linus/master

s390/qdio: remove remaining tasklet & timer code

2021-07-27T07:39:18Z

Both qdio drivers have moved away from using qdio's internal tasklet and timer mechanisms for Output Queues. Rip out all the leftovers. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Heiko Carstens

s390/qdio: inline qdio_kick_handler()

2021-02-13T16:17:55Z

We don't kick the handler for Input Queues anymore. Move the remaining code into its only caller. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

s390/qdio: track time of last data IRQ for each device

2021-02-09T14:57:04Z

We currently track the time of the most recent QDIO Adapter Interrupt. This is a system-wide timestamp (as such interrupts are not bound to one specific qdio device). If interrupt processing stalls on one device but is functional for a different device, the timestamp continues to be updated and is of no help for problem diagnosis. So for debugging purposes also track the time of the last Data IRQ on a per-device level. Collect this data in the legacy non-AI path as well. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

s390/qdio: remove Input tasklet code

2021-02-09T14:57:04Z

Both qeth and zfcp have fully moved to the polling-driven flow for Input Queues with commit 0a6e634535f1 ("s390/qdio: extend polling support to multiple queues") and commit 0b524abc2dd1 ("scsi: zfcp: Lift Input Queue tasklet from qdio"). So remove the tasklet code for Input Queues, streamline the IRQ handlers and push the tasklet struct into struct qdio_output_q. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

s390/qdio: fix statistics for 128 SBALs

2020-07-20T08:55:18Z

Old code would only scan up to 127 SBALs at once. So the last statistics bucket was set aside to count "discovered 127 SBALs with new work" events. But nowadays we allow to scan all 128 SBALs for Output Queues, and a subsequent patch will introduce the same for Input Queues. So fix up the accounting to use the last bucket only when all 128 SBALs have been discovered with new work. Signed-off-by: Julian Wiedmann Signed-off-by: Heiko Carstens

s390/qdio: reduce SLSB writes during Input Queue processing

2020-06-16T11:44:04Z

Streamline the processing of QDIO Input Queues, and remove some intermittent SLSB updates (no deleting of old ACKs, no redundant transitions through NOT_INIT). Rather than counting ACKs, we now keep track of the whole batch of SBALs that were completed during the current polling cycle. Most completed SBALs stay in their initial state (ie. PRIMED or ERROR), except that the most recent SBAL in each sub-run is ACKed for IRQ reduction. The only logic changes happen in inbound_handle_work(), the other delta is just a renaming of the variables that track the SBAL batch. Note that in particular we don't need to flip the _oldest_ SBAL to an idle state (eg. NOT_INIT or ACKed) as a guard against catching our own tail. Since get_inbound_buffer_frontier() will never scan more than the remaining nr_buf_used SBALs, this scenario just doesn't occur. Signed-off-by: Julian Wiedmann Signed-off-by: Vasily Gorbik

s390/qdio: cleanly split alloc and establish

2020-04-06T11:13:50Z

All that qdio_allocate() actually uses from the init_data is the cdev, and the number of Input and Output Queues. Have the driver pass those as parameters, and defer the init_data processing into qdio_establish(). This includes writing per-device(!) trace entries, and most of the sanity checks. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

Merge tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2020-04-04T16:45:50Z

Pull s390 updates from Vasily Gorbik: - Update maintainers. Niklas Schnelle takes over zpci and Vineeth Vijayan common io code. - Extend cpuinfo to include topology information. - Add new extended counters for IBM z15 and sampling buffer allocation rework in perf code. - Add control over zeroing out memory during system restart. - CCA protected key block version 2 support and other fixes/improvements in crypto code. - Convert to new fallthrough; annotations. - Replace zero-length arrays with flexible-arrays. - QDIO debugfs and other small improvements. - Drop 2-level paging support optimization for compat tasks. Varios mm cleanups. - Remove broken and unused hibernate / power management support. - Remove fake numa support which does not bring any benefits. - Exclude offline CPUs from CPU topology masks to be more consistent with other architectures. - Prevent last branching instruction address leaking to userspace. - Other small various fixes and improvements all over the code. * tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (57 commits) s390/mm: cleanup init_new_context() callback s390/mm: cleanup virtual memory constants usage s390/mm: remove page table downgrade support s390/qdio: set qdio_irq->cdev at allocation time s390/qdio: remove unused function declarations s390/ccwgroup: remove pm support s390/ap: remove power management code from ap bus and drivers s390/zcrypt: use kvmalloc instead of kmalloc for 256k alloc s390/mm: cleanup arch_get_unmapped_area() and friends s390/ism: remove pm support s390/cio: use fallthrough; s390/vfio: use fallthrough; s390/zcrypt: use fallthrough; s390: use fallthrough; s390/cpum_sf: Fix wrong page count in error message s390/diag: fix display of diagnose call statistics s390/ap: Remove ap device suspend and resume callbacks s390/pci: Improve handling of unset UID s390/pci: Fix zpci_alloc_domain() over allocation s390/qdio: pass ISC as parameter to chsc_sadc() ...

s390/qdio: set qdio_irq->cdev at allocation time

2020-03-27T09:22:48Z

Set up qdio_irq->cdev right when the qdio_irq struct is allocated, so that all subsequent code can rely on this pointer. Then convert two helper functions to not pass a cdev parameter around. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

s390/qdio: extend polling support to multiple queues

2020-03-25T19:07:15Z

When the support for polling drivers was initially added, it only considered Input Queue 0. But as QDIO interrupts are actually for the full device and not a single queue, this doesn't really fit for configurations where multiple Input Queues are used. Rework the qdio code so that interrupts for a polling driver are not split up into actions for each queue. Instead deliver the interrupt as a single event, and let the driver decide which queue needs what action. When re-enabling the QDIO interrupt via qdio_start_irq(), this means that the qdio code needs to (1) put _all_ eligible queues back into a state where they raise IRQs, (2) and afterwards check _all_ eligible queues for new work to bridge the race window. On the qeth side of things (as the only qdio polling driver), we can now add CQ polling support to the main NAPI poll routine. It doesn't consume NAPI budget, and to avoid hogging the CPU we yield control after completing one full queue worth of buffers. The subsequent qdio_start_irq() will check for any additional work, and have us re-schedule the NAPI instance accordingly. Signed-off-by: Julian Wiedmann Acked-by: Heiko Carstens Signed-off-by: David S. Miller