forked from Minki/linux
mainlining shenanigans
ff9f47f6f0
smaps_rollup will try to grab mmap_lock and go through the whole vma list until it finishes the iterating. When encountering large processes, the mmap_lock will be held for a longer time, which may block other write requests like mmap and munmap from progressing smoothly. There are upcoming mmap_lock optimizations like range-based locks, but the lock applied to smaps_rollup would be the coarse type, which doesn't avoid the occurrence of unpleasant contention. To solve aforementioned issue, we add a check which detects whether anyone wants to grab mmap_lock for write attempts. Signed-off-by: Chinwen Chang <chinwen.chang@mediatek.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Steven Price <steven.price@arm.com> Cc: Michel Lespinasse <walken@google.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: Chinwen Chang <chinwen.chang@mediatek.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Song Liu <songliubraving@fb.com> Cc: Jimmy Assarsson <jimmyassarsson@gmail.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Daniel Kiss <daniel.kiss@arm.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Link: http://lkml.kernel.org/r/1597715898-3854-4-git-send-email-chinwen.chang@mediatek.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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.