NVMe: Correctly handle IOCTL_SUBMIT_IO when cpus > online queues

PATCH New Sam Bradshaw 1 participant 1 message Jul 29, 2014

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Block layer NVMe

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Sam Bradshaw

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2014-07-29 20:31 UTC #0 lore raw

PATCH v2 1/1 NVMe: Correctly handle IOCTL_SUBMIT_IO when cpus > online queues

nvme_submit_io_cmd() uses smp_processor_id() to pick an IO queue index. This patch fixes the case where there are more cpus from which the ioctl call can originate than online queues, which can happen when a device supports or was allocated fewer interrupt vectors than exist cpu cores.

Thanks to Keith Busch for the implementation suggestion.

Signed-off-by Sam Bradshaw <sbradshaw at micron.com>

---

drivers/block/nvme-core.c +2 -2

index 28aec2d..e18b67b 100644
@@ -979,8 +979,8 @@ int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
 int nvme_submit_io_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
 								u32 *result)
 {
-	return nvme_submit_sync_cmd(dev, smp_processor_id() + 1, cmd, result,
-							NVME_IO_TIMEOUT);
+	return nvme_submit_sync_cmd(dev, this_cpu_read(*dev->io_queue), cmd,
+						result,	NVME_IO_TIMEOUT);
 }
 
 static int nvme_submit_admin_cmd_async(struct nvme_dev *dev,