928da37a22
Mapping as little as 64GB can take more than 10 seconds, triggering issues on kernels with CONFIG_PREEMPT_NONE=y. ib_umem_get() already splits the work in 2MB units on x86_64, adding a cond_resched() in the long-lasting loop is enough to solve the issue. Note that sg_alloc_table() can still use more than 100 ms, which is also problematic. This might be addressed later in ib_umem_add_sg_table(), adding new blocks in sgl on demand. Link: https://lore.kernel.org/r/20200730015755.1827498-1-edumazet@google.com Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.