diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2021-12-06 23:51:52 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2021-12-16 22:22:20 +0100 |
| commit | cd6cf06590b9792340dceaa285138777f3cc4d90 (patch) | |
| tree | 7012825c2c5947ddc13516012f5d4bfb77f4487a /include/linux/msi.h | |
| parent | bf5e758f02fc739589dcc6a3395c3a3eb77b5c90 (diff) | |
genirq/msi: Convert storage to xarray
The current linked list storage for MSI descriptors is suboptimal in
several ways:
1) Looking up a MSI desciptor requires a O(n) list walk in the worst case
2) The upcoming support of runtime expansion of MSI-X vectors would need
to do a full list walk to figure out whether a particular index is
already associated.
3) Runtime expansion of sparse allocations is even more complex as the
current implementation assumes an ordered list (increasing MSI index).
Use an xarray which solves all of the above problems nicely.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211206210749.280627070@linutronix.de
Diffstat (limited to 'include/linux/msi.h')
| -rw-r--r-- | include/linux/msi.h | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/include/linux/msi.h b/include/linux/msi.h index 1a00367d2cfa..fc918a658d48 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -17,6 +17,7 @@ */ #include <linux/cpumask.h> +#include <linux/xarray.h> #include <linux/mutex.h> #include <linux/list.h> #include <asm/msi.h> @@ -123,7 +124,6 @@ struct pci_msi_desc { /** * struct msi_desc - Descriptor structure for MSI based interrupts - * @list: List head for management * @irq: The base interrupt number * @nvec_used: The number of vectors used * @dev: Pointer to the device which uses this descriptor @@ -140,7 +140,6 @@ struct pci_msi_desc { */ struct msi_desc { /* Shared device/bus type independent data */ - struct list_head list; unsigned int irq; unsigned int nvec_used; struct device *dev; @@ -176,16 +175,16 @@ enum msi_desc_filter { * msi_device_data - MSI per device data * @properties: MSI properties which are interesting to drivers * @platform_data: Platform-MSI specific data - * @list: List of MSI descriptors associated to the device - * @mutex: Mutex protecting the MSI list - * @__next: Cached pointer to the next entry for iterators + * @mutex: Mutex protecting the MSI descriptor store + * @__store: Xarray for storing MSI descriptor pointers + * @__iter_idx: Index to search the next entry for iterators */ struct msi_device_data { unsigned long properties; struct platform_msi_priv_data *platform_data; - struct list_head list; struct mutex mutex; - struct msi_desc *__next; + struct xarray __store; + unsigned long __iter_idx; }; int msi_setup_device_data(struct device *dev); |