[v8,for-next,0/3] IB/core: Obtaining subnet_prefix from cache in

Message

Anand Khoje July 12, 2021, 12:26 p.m. UTC

This v8 of patch series is used to read the port_attribute subnet_prefix
from a valid cache entry instead of having to call
device->ops.query_gid() for Infiniband link-layer devices in
__ib_query_port().

In the event of a cache update, the value for subnet_prefix gets read
using device->ops.query_gid() in config_non_roce_gid_cache().

It also re-orders the initialization of lock cache_lock of struct ib_device
such that the lock is initialized before its first use in __ib_query_port()
during device initialization.

Anand Khoje (3):
  IB/core: Updating cache for subnet_prefix in
    config_non_roce_gid_cache()
  IB/core: Shifting initialization of device->cache_lock
  IB/core: Read subnet_prefix in ib_query_port via cache.

 drivers/infiniband/core/cache.c  | 10 +++++-----
 drivers/infiniband/core/device.c | 10 ++++------
 2 files changed, 9 insertions(+), 11 deletions(-)

---
v1 -> v2:
    -   Split the v1 patch in 3 patches as per Leon's suggestion.

v2 -> v3:
    -   Added changes as per Mark Zhang's suggestion of clearing
        flags in git_table_cleanup_one().
v3 -> v4:
    -   Removed the enum ib_port_data_flags and 8 byte flags from
        struct ib_port_data, and the set_bit()/clear_bit() API
        used to update this flag as that was not necessary.
        Done to keep the code simple.
    -   Added code to read subnet_prefix from updated GID cache in the
        event of cache update. Prior to this change, ib_cache_update
        was reading the value for subnet_prefix via ib_query_port(),
        due to this patch, we ended up reading a stale cached value of
        subnet_prefix.
v4 -> v5:
    -   Removed the code to reset cache_is_initialised bit from cleanup
        as per Leon's suggestion.
    -   Removed ib_cache_is_initialised() function.

v5 -> v6:
    -   Added changes as per Jason's suggestion of updating subnet_prefix
        in config_non_roce_gid_cache() and removing the flag
        cache_is_initialized in __ib_query_port().

v6 -> v7:
    -   Reordering the initialization of cache_lock, as the previous
        version caused an access to uninitialized cache_lock.

v7 -> v8:
    -   Resending the v7 of the patch-set after rebasing on the new rc1.
        There has been no change in the patches between v7 and v8 as v7
        patches applied cleanly after rebasing to 5.14-rc1.
---

Comments

Jason Gunthorpe July 16, 2021, 2:08 p.m. UTC | #1

On Mon, Jul 12, 2021 at 05:56:22PM +0530, Anand Khoje wrote:
> This v8 of patch series is used to read the port_attribute subnet_prefix
> from a valid cache entry instead of having to call
> device->ops.query_gid() for Infiniband link-layer devices in
> __ib_query_port().
> 
> In the event of a cache update, the value for subnet_prefix gets read
> using device->ops.query_gid() in config_non_roce_gid_cache().
> 
> It also re-orders the initialization of lock cache_lock of struct ib_device
> such that the lock is initialized before its first use in __ib_query_port()
> during device initialization.
> 
> Anand Khoje (3):
>   IB/core: Updating cache for subnet_prefix in
>     config_non_roce_gid_cache()
>   IB/core: Shifting initialization of device->cache_lock
>   IB/core: Read subnet_prefix in ib_query_port via cache.
> 
>  drivers/infiniband/core/cache.c  | 10 +++++-----
>  drivers/infiniband/core/device.c | 10 ++++------
>  2 files changed, 9 insertions(+), 11 deletions(-)

Applied to for-next, thanks

Jason