mlx5-updates-2020-11-03
This series includes updates to mlx5 software steering component.
1) Few improvements in the DR area, such as removing unneeded checks,
renaming to better general names, refactor in some places, etc.
2) Software steering (DR) Memory management improvements
This patch series contains SW Steering memory management improvements:
using buddy allocator instead of an existing bucket allocator, and
several other optimizations.
The buddy system is a memory allocation and management algorithm
that manages memory in power of two increments.
The algorithm is well-known and well-described, such as here:
https://en.wikipedia.org/wiki/Buddy_memory_allocation
Linux uses this algorithm for managing and allocating physical pages,
as described here:
https://www.kernel.org/doc/gorman/html/understand/understand009.html
In our case, although the algorithm in principal is similar to the
Linux physical page allocator, the "building blocks" and the circumstances
are different: in SW steering, buddy allocator doesn't really allocates
a memory, but rather manages ICM (Interconnect Context Memory) that was
previously allocated and registered.
The ICM memory that is used in SW steering is always power
of 2 (order), so buddy system is a good fit for this.
Patches in this series:
[PATH 4] net/mlx5: DR, Add buddy allocator utilities
This patch adds a modified implementation of a well-known buddy allocator,
adjusted for SW steering needs: the algorithm in principal is similar to
the Linux physical page allocator, but in our case buddy allocator doesn't
really allocate a memory, but rather manages ICM memory that was previously
allocated and registered.
[PATH 5] net/mlx5: DR, Handle ICM memory via buddy allocation instead of bucket management
This patch changes ICM management of SW steering to use buddy-system mechanism
Instead of the previous bucket management.
[PATH 6] net/mlx5: DR, Sync chunks only during free
This patch makes syncing happen only when freeing memory chunks.
[PATH 7] net/mlx5: DR, ICM memory pools sync optimization
This patch adds tracking of pool's "hot" memory and makes the
check whether steering sync is required much shorter and faster.
[PATH 8] net/mlx5: DR, Free buddy ICM memory if it is unused
This patch adds tracking buddy's used ICM memory,
and frees the buddy if all its memory becomes unused.
3) Misc code cleanups
net: mlx5: Replace in_irq() usage
mlx5_eq_async_int() uses in_irq() to decide whether eq::lock needs to be
acquired and released with spin_[un]lock() or the irq saving/restoring
variants.
The usage of in_*() in drivers is phased out and Linus clearly requested
that code which changes behaviour depending on context should either be
seperated or the context be conveyed in an argument passed by the caller,
which usually knows the context.
mlx5_eq_async_int() knows the context via the action argument already so
using it for the lock variant decision is a straight forward replacement
for in_irq().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
1 file changed
