forked from luck/tmp_suning_uos_patched
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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.. | ||
array.c | ||
base.c | ||
bootconfig.c | ||
cmdline.c | ||
consoles.c | ||
cpuinfo.c | ||
devices.c | ||
fd.c | ||
fd.h | ||
generic.c | ||
inode.c | ||
internal.h | ||
interrupts.c | ||
Kconfig | ||
kcore.c | ||
kmsg.c | ||
loadavg.c | ||
Makefile | ||
meminfo.c | ||
namespaces.c | ||
nommu.c | ||
page.c | ||
proc_net.c | ||
proc_sysctl.c | ||
proc_tty.c | ||
root.c | ||
self.c | ||
softirqs.c | ||
stat.c | ||
task_mmu.c | ||
task_nommu.c | ||
thread_self.c | ||
uptime.c | ||
util.c | ||
version.c | ||
vmcore.c |