mainlining shenanigans
Another thing making netns dismantles potentially very slow is located in gro_cells_destroy(), whenever cleanup_net() has to remove a device using gro_cells framework. RTNL is not held at this stage, so synchronize_net() is calling synchronize_rcu(): netdev_run_todo() ip_tunnel_dev_free() gro_cells_destroy() synchronize_net() synchronize_rcu() // Ouch. This patch uses call_rcu(), and gave me a 25x performance improvement in my tests. cleanup_net() is no longer blocked ~10 ms per synchronize_rcu() call. In the case we could not allocate the memory needed to queue the deferred free, use synchronize_rcu_expedited() v2: made percpu_free_defer_callback() static Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20220220041155.607637-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
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.