diff options
| author | Joel Fernandes <joelaf@google.com> | 2016-12-13 03:44:26 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-13 05:55:08 +0300 |
| commit | 763b218ddfaf56761c19923beb7e16656f66ec62 (patch) | |
| tree | d20c1ca842ce466541b1b98ed0fc5589f51a0897 | |
| parent | f9e09977671b618aeb25ddc0d4c9a84d5b5cde9d (diff) | |
| download | linux-763b218ddfaf56761c19923beb7e16656f66ec62.tar.xz | |
mm: add preempt points into __purge_vmap_area_lazy()
Use cond_resched_lock to avoid holding the vmap_area_lock for a
potentially long time and thus creating bad latencies for various
workloads.
[hch: split from a larger patch by Joel, wrote the crappy changelog]
Link: http://lkml.kernel.org/r/1479474236-4139-11-git-send-email-hch@lst.de
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/vmalloc.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index d3c1f5ee48b4..a5584384eabc 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -628,7 +628,7 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end) struct llist_node *valist; struct vmap_area *va; struct vmap_area *n_va; - int nr = 0; + bool do_free = false; lockdep_assert_held(&vmap_purge_lock); @@ -638,18 +638,22 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end) start = va->va_start; if (va->va_end > end) end = va->va_end; - nr += (va->va_end - va->va_start) >> PAGE_SHIFT; + do_free = true; } - if (!nr) + if (!do_free) return false; - atomic_sub(nr, &vmap_lazy_nr); flush_tlb_kernel_range(start, end); spin_lock(&vmap_area_lock); - llist_for_each_entry_safe(va, n_va, valist, purge_list) + llist_for_each_entry_safe(va, n_va, valist, purge_list) { + int nr = (va->va_end - va->va_start) >> PAGE_SHIFT; + __free_vmap_area(va); + atomic_sub(nr, &vmap_lazy_nr); + cond_resched_lock(&vmap_area_lock); + } spin_unlock(&vmap_area_lock); return true; } |