Messages in this thread | | | Date | Tue, 6 Jun 2023 17:43:05 +0100 | From | Jonathan Cameron <> | Subject | Re: [PATCH v4 5/5] hwtracing: hisi_ptt: Fix potential sleep in atomic context |
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On Tue, 6 Jun 2023 22:22:44 +0800 Yicong Yang <yangyicong@huawei.com> wrote:
> From: Yicong Yang <yangyicong@hisilicon.com> > > We're using pci_irq_vector() to obtain the interrupt number and then > bind it to the CPU start perf under the protection of spinlock in > pmu::start(). pci_irq_vector() might sleep since [1] because it will > call msi_domain_get_virq() to get the MSI interrupt number and it > needs to acquire dev->msi.data->mutex. Getting a mutex will sleep on > contention. So use pci_irq_vector() in an atomic context is problematic. > > This patch cached the interrupt number in the probe() and uses the > cached data instead to avoid potential sleep. > > [1] commit 82ff8e6b78fc ("PCI/MSI: Use msi_get_virq() in pci_get_vector()") > Fixes: ff0de066b463 ("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device") > Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
LGTM
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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