A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-30 03:27:44 -04:00
Code Issues Projects Releases Packages Wiki Activity

mm: split 'tlb_flush_mmu()' into tlb flushing and memory freeing parts

Browse source 
The mmu-gather operation 'tlb_flush_mmu()' has done two things: the
actual tlb flush operation, and the batched freeing of the pages that
the TLB entries pointed at.

This splits the operation into separate phases, so that the forced
batched flushing done by zap_pte_range() can now do the actual TLB flush
while still holding the page table lock, but delay the batched freeing
of all the pages to after the lock has been dropped.

This in turn allows us to avoid a race condition between
set_page_dirty() (as called by zap_pte_range() when it finds a dirty
shared memory pte) and page_mkclean(): because we now flush all the
dirty page data from the TLB's while holding the pte lock,
page_mkclean() will be held up walking the (recently cleaned) page
tables until after the TLB entries have been flushed from all CPU's.

Reported-by: Benjamin Herrenschmidt <[email protected]>
Tested-by: Dave Hansen <[email protected]>
Acked-by: Hugh Dickins <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Russell King - ARM Linux <[email protected]>
Cc: Tony Luck <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Linus Torvalds 2014-04-25 16:05:40 -07:00
commit 1cf35d4771
6 changed files with 111 additions and 33 deletions
Download patch file Download diff file Expand all files Collapse all files

16
arch/um/include/asm/tlb.h
View file

@ -58,14 +58,26 @@ tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start
extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
unsigned long end);
static inline void
tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
{
flush_tlb_mm_range(tlb->mm, tlb->start, tlb->end);
}
static inline void
tlb_flush_mmu_free(struct mmu_gather *tlb)
{
init_tlb_gather(tlb);
}
static inline void
tlb_flush_mmu(struct mmu_gather *tlb)
{
if (!tlb->need_flush)
return;
flush_tlb_mm_range(tlb->mm, tlb->start, tlb->end);
init_tlb_gather(tlb);
tlb_flush_mmu_tlbonly(tlb);
tlb_flush_mmu_free(tlb);
}
/* tlb_finish_mmu