| Message ID | 1447034266-28003-4-git-send-email-okaya@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 11/09/2015 02:57 AM, Sinan Kaya wrote: > The mpt2sas and mpt3sas drivers are spinning forever in > their IRQ handlers if there are a lot of jobs queued up > by the PCIe card. This handler is causing spikes for > the rest of the system and sluggish behavior. > > Marking all MSI interrupts as non-shared and moving the > MSI interrupts to thread context. This relexes the rest > of the system execution. > NACK. If there is a scalability issue when handling interrupts it should be fixed in the driver directly. Looking at the driver is should be possible to implement a worker thread handling the reply descriptor, and having the interrupt only to fetch the reply descriptor. Cheers, Hannes
On 11/9/2015 2:15 AM, Hannes Reinecke wrote: > On 11/09/2015 02:57 AM, Sinan Kaya wrote: >> The mpt2sas and mpt3sas drivers are spinning forever in >> their IRQ handlers if there are a lot of jobs queued up >> by the PCIe card. This handler is causing spikes for >> the rest of the system and sluggish behavior. >> >> Marking all MSI interrupts as non-shared and moving the >> MSI interrupts to thread context. This relexes the rest >> of the system execution. >> > NACK. > > If there is a scalability issue when handling interrupts > it should be fixed in the driver directly. > > Looking at the driver is should be possible to implement > a worker thread handling the reply descriptor, and having the > interrupt only to fetch the reply descriptor. I'll take a look. > > Cheers, > > Hannes >
On 11/9/2015 2:15 AM, Hannes Reinecke wrote: > On 11/09/2015 02:57 AM, Sinan Kaya wrote: >> The mpt2sas and mpt3sas drivers are spinning forever in >> their IRQ handlers if there are a lot of jobs queued up >> by the PCIe card. This handler is causing spikes for >> the rest of the system and sluggish behavior. >> >> Marking all MSI interrupts as non-shared and moving the >> MSI interrupts to thread context. This relexes the rest >> of the system execution. >> > NACK. > > If there is a scalability issue when handling interrupts > it should be fixed in the driver directly. > > Looking at the driver is should be possible to implement > a worker thread handling the reply descriptor, and having the > interrupt only to fetch the reply descriptor. > Can you go into the detail about which part of the _base_interrupt function needs to be executed in ISR context and which part can be queued up to worker thread? I'm not familiar with the hardware or the code. That's why, I moved the entire ISR into the thread context. > Cheers, > > Hannes >
On 11/10/2015 12:59 AM, Sinan Kaya wrote: > > On 11/9/2015 2:15 AM, Hannes Reinecke wrote: >> On 11/09/2015 02:57 AM, Sinan Kaya wrote: >>> The mpt2sas and mpt3sas drivers are spinning forever in >>> their IRQ handlers if there are a lot of jobs queued up >>> by the PCIe card. This handler is causing spikes for >>> the rest of the system and sluggish behavior. >>> >>> Marking all MSI interrupts as non-shared and moving the >>> MSI interrupts to thread context. This relexes the rest >>> of the system execution. >>> >> NACK. >> >> If there is a scalability issue when handling interrupts >> it should be fixed in the driver directly. >> >> Looking at the driver is should be possible to implement >> a worker thread handling the reply descriptor, and having the >> interrupt only to fetch the reply descriptor. >> > > Can you go into the detail about which part of the _base_interrupt > function needs to be executed in ISR context and which part can be > queued up to worker thread? > > I'm not familiar with the hardware or the code. That's why, I moved the > entire ISR into the thread context. Hannes or others, any suggestions? Thanks, Christopher Covington
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c index c61c82a..b619a0e 100644 --- a/drivers/scsi/mpt2sas/mpt2sas_base.c +++ b/drivers/scsi/mpt2sas/mpt2sas_base.c @@ -1359,14 +1359,18 @@ _base_request_irq(struct MPT2SAS_ADAPTER *ioc, u8 index, u32 vector) cpumask_clear(reply_q->affinity_hint); atomic_set(&reply_q->busy, 0); - if (ioc->msix_enable) + if (ioc->msix_enable) { snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d-msix%d", MPT2SAS_DRIVER_NAME, ioc->id, index); - else + r = request_threaded_irq(vector, NULL, _base_interrupt, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, + reply_q->name, reply_q); + } else { snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d", MPT2SAS_DRIVER_NAME, ioc->id); - r = request_irq(vector, _base_interrupt, IRQF_SHARED, reply_q->name, - reply_q); + r = request_irq(vector, _base_interrupt, IRQF_SHARED, + reply_q->name, reply_q); + } if (r) { printk(MPT2SAS_ERR_FMT "unable to allocate interrupt %d!\n", reply_q->name, vector); diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c index 6dc391c..62bee43 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_base.c +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c @@ -1661,14 +1661,19 @@ _base_request_irq(struct MPT3SAS_ADAPTER *ioc, u8 index, u32 vector) cpumask_clear(reply_q->affinity_hint); atomic_set(&reply_q->busy, 0); - if (ioc->msix_enable) + if (ioc->msix_enable) { snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d-msix%d", MPT3SAS_DRIVER_NAME, ioc->id, index); - else + + r = request_threaded_irq(vector, NULL, _base_interrupt, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, + reply_q->name, reply_q); + } else { snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d", MPT3SAS_DRIVER_NAME, ioc->id); - r = request_irq(vector, _base_interrupt, IRQF_SHARED, reply_q->name, - reply_q); + r = request_irq(vector, _base_interrupt, IRQF_SHARED, + reply_q->name, reply_q); + } if (r) { pr_err(MPT3SAS_FMT "unable to allocate interrupt %d!\n", reply_q->name, vector);
The mpt2sas and mpt3sas drivers are spinning forever in their IRQ handlers if there are a lot of jobs queued up by the PCIe card. This handler is causing spikes for the rest of the system and sluggish behavior. Marking all MSI interrupts as non-shared and moving the MSI interrupts to thread context. This relexes the rest of the system execution. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> --- drivers/scsi/mpt2sas/mpt2sas_base.c | 12 ++++++++---- drivers/scsi/mpt3sas/mpt3sas_base.c | 13 +++++++++---- 2 files changed, 17 insertions(+), 8 deletions(-)