mainlining shenanigans
0e39037b31
Currently, we convert the error state into a string every time we read from sysfs (and sysfs reads in page size (4KiB) chunks). We do try to window the string and only capture the portion that is being read, but that means that we must always convert up to the window to find the start. For a very large error state bordering on EXEC_OBJECT_CAPTURE abuse, this is noticeable as it degrades to O(N^2)! As we do not have a convenient hook for sysfs open(), and we would like to keep the lazy conversion into a string, do the conversion of the whole string on the first read and keep the string until the error state is freed. v2: Don't double advance simple_read_from_buffer v3: Due to extreme pain of lack of vrealloc, use a scatterlist v4: Keep the forward iterator loosely cached v5: Stylistic improvements to reduce patch size Reported-by: Jason Ekstrand <jason@jlekstrand.net> Testcase: igt/gem_exec_capture/many* Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Jason Ekstrand <jason@jlekstrand.net> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181123132325.26541-1-chris@chris-wilson.co.uk |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
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.