Age | Commit message (Collapse) | Author | Files | Lines |
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Pageblocks have an associated bitmap to store migrate types and whether
the pageblock should be skipped during compaction. The bitmap may be
associated with a memory section or a zone but the zone is looked up
unconditionally. The compiler should optimise this away automatically
so this is a cosmetic patch only in many cases.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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__dec_zone_state is cheaper to use for removing an order-0 page as it
has fewer conditions to check.
The performance difference on a page allocator microbenchmark is;
4.6.0-rc2 4.6.0-rc2
optiter-v1r20 decstat-v1r20
Min alloc-odr0-1 382.00 ( 0.00%) 381.00 ( 0.26%)
Min alloc-odr0-2 282.00 ( 0.00%) 275.00 ( 2.48%)
Min alloc-odr0-4 233.00 ( 0.00%) 229.00 ( 1.72%)
Min alloc-odr0-8 203.00 ( 0.00%) 199.00 ( 1.97%)
Min alloc-odr0-16 188.00 ( 0.00%) 186.00 ( 1.06%)
Min alloc-odr0-32 182.00 ( 0.00%) 179.00 ( 1.65%)
Min alloc-odr0-64 177.00 ( 0.00%) 174.00 ( 1.69%)
Min alloc-odr0-128 175.00 ( 0.00%) 172.00 ( 1.71%)
Min alloc-odr0-256 184.00 ( 0.00%) 181.00 ( 1.63%)
Min alloc-odr0-512 197.00 ( 0.00%) 193.00 ( 2.03%)
Min alloc-odr0-1024 203.00 ( 0.00%) 201.00 ( 0.99%)
Min alloc-odr0-2048 209.00 ( 0.00%) 206.00 ( 1.44%)
Min alloc-odr0-4096 214.00 ( 0.00%) 212.00 ( 0.93%)
Min alloc-odr0-8192 218.00 ( 0.00%) 215.00 ( 1.38%)
Min alloc-odr0-16384 219.00 ( 0.00%) 216.00 ( 1.37%)
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The page allocator iterates through a zonelist for zones that match the
addressing limitations and nodemask of the caller but many allocations
will not be restricted. Despite this, there is always functional call
overhead which builds up.
This patch inlines the optimistic basic case and only calls the iterator
function for the complex case. A hindrance was the fact that
cpuset_current_mems_allowed is used in the fastpath as the allowed
nodemask even though all nodes are allowed on most systems. The patch
handles this by only considering cpuset_current_mems_allowed if a cpuset
exists. As well as being faster in the fast-path, this removes some
junk in the slowpath.
The performance difference on a page allocator microbenchmark is;
4.6.0-rc2 4.6.0-rc2
statinline-v1r20 optiter-v1r20
Min alloc-odr0-1 412.00 ( 0.00%) 382.00 ( 7.28%)
Min alloc-odr0-2 301.00 ( 0.00%) 282.00 ( 6.31%)
Min alloc-odr0-4 247.00 ( 0.00%) 233.00 ( 5.67%)
Min alloc-odr0-8 215.00 ( 0.00%) 203.00 ( 5.58%)
Min alloc-odr0-16 199.00 ( 0.00%) 188.00 ( 5.53%)
Min alloc-odr0-32 191.00 ( 0.00%) 182.00 ( 4.71%)
Min alloc-odr0-64 187.00 ( 0.00%) 177.00 ( 5.35%)
Min alloc-odr0-128 185.00 ( 0.00%) 175.00 ( 5.41%)
Min alloc-odr0-256 193.00 ( 0.00%) 184.00 ( 4.66%)
Min alloc-odr0-512 207.00 ( 0.00%) 197.00 ( 4.83%)
Min alloc-odr0-1024 213.00 ( 0.00%) 203.00 ( 4.69%)
Min alloc-odr0-2048 220.00 ( 0.00%) 209.00 ( 5.00%)
Min alloc-odr0-4096 226.00 ( 0.00%) 214.00 ( 5.31%)
Min alloc-odr0-8192 229.00 ( 0.00%) 218.00 ( 4.80%)
Min alloc-odr0-16384 229.00 ( 0.00%) 219.00 ( 4.37%)
perf indicated that next_zones_zonelist disappeared in the profile and
__next_zones_zonelist did not appear. This is expected as the
micro-benchmark would hit the inlined fast-path every time.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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zone_statistics has one call-site but it's a public function. Make it
static and inline.
The performance difference on a page allocator microbenchmark is;
4.6.0-rc2 4.6.0-rc2
statbranch-v1r20 statinline-v1r20
Min alloc-odr0-1 419.00 ( 0.00%) 412.00 ( 1.67%)
Min alloc-odr0-2 305.00 ( 0.00%) 301.00 ( 1.31%)
Min alloc-odr0-4 250.00 ( 0.00%) 247.00 ( 1.20%)
Min alloc-odr0-8 219.00 ( 0.00%) 215.00 ( 1.83%)
Min alloc-odr0-16 203.00 ( 0.00%) 199.00 ( 1.97%)
Min alloc-odr0-32 195.00 ( 0.00%) 191.00 ( 2.05%)
Min alloc-odr0-64 191.00 ( 0.00%) 187.00 ( 2.09%)
Min alloc-odr0-128 189.00 ( 0.00%) 185.00 ( 2.12%)
Min alloc-odr0-256 198.00 ( 0.00%) 193.00 ( 2.53%)
Min alloc-odr0-512 210.00 ( 0.00%) 207.00 ( 1.43%)
Min alloc-odr0-1024 216.00 ( 0.00%) 213.00 ( 1.39%)
Min alloc-odr0-2048 221.00 ( 0.00%) 220.00 ( 0.45%)
Min alloc-odr0-4096 227.00 ( 0.00%) 226.00 ( 0.44%)
Min alloc-odr0-8192 232.00 ( 0.00%) 229.00 ( 1.29%)
Min alloc-odr0-16384 232.00 ( 0.00%) 229.00 ( 1.29%)
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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zone_statistics has more branches than it really needs to take an
unlikely GFP flag into account. Reduce the number and annotate the
unlikely flag.
The performance difference on a page allocator microbenchmark is;
4.6.0-rc2 4.6.0-rc2
nocompound-v1r10 statbranch-v1r10
Min alloc-odr0-1 417.00 ( 0.00%) 419.00 ( -0.48%)
Min alloc-odr0-2 308.00 ( 0.00%) 305.00 ( 0.97%)
Min alloc-odr0-4 253.00 ( 0.00%) 250.00 ( 1.19%)
Min alloc-odr0-8 221.00 ( 0.00%) 219.00 ( 0.90%)
Min alloc-odr0-16 205.00 ( 0.00%) 203.00 ( 0.98%)
Min alloc-odr0-32 199.00 ( 0.00%) 195.00 ( 2.01%)
Min alloc-odr0-64 193.00 ( 0.00%) 191.00 ( 1.04%)
Min alloc-odr0-128 191.00 ( 0.00%) 189.00 ( 1.05%)
Min alloc-odr0-256 200.00 ( 0.00%) 198.00 ( 1.00%)
Min alloc-odr0-512 212.00 ( 0.00%) 210.00 ( 0.94%)
Min alloc-odr0-1024 219.00 ( 0.00%) 216.00 ( 1.37%)
Min alloc-odr0-2048 225.00 ( 0.00%) 221.00 ( 1.78%)
Min alloc-odr0-4096 231.00 ( 0.00%) 227.00 ( 1.73%)
Min alloc-odr0-8192 234.00 ( 0.00%) 232.00 ( 0.85%)
Min alloc-odr0-16384 234.00 ( 0.00%) 232.00 ( 0.85%)
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The PageAnon check always checks for compound_head but this is a
relatively expensive check if the caller already knows the page is a
head page. This patch creates a helper and uses it in the page free
path which only operates on head pages.
With this patch and "Only check PageCompound for high-order pages", the
performance difference on a page allocator microbenchmark is;
4.6.0-rc2 4.6.0-rc2
vanilla nocompound-v1r20
Min alloc-odr0-1 425.00 ( 0.00%) 417.00 ( 1.88%)
Min alloc-odr0-2 313.00 ( 0.00%) 308.00 ( 1.60%)
Min alloc-odr0-4 257.00 ( 0.00%) 253.00 ( 1.56%)
Min alloc-odr0-8 224.00 ( 0.00%) 221.00 ( 1.34%)
Min alloc-odr0-16 208.00 ( 0.00%) 205.00 ( 1.44%)
Min alloc-odr0-32 199.00 ( 0.00%) 199.00 ( 0.00%)
Min alloc-odr0-64 195.00 ( 0.00%) 193.00 ( 1.03%)
Min alloc-odr0-128 192.00 ( 0.00%) 191.00 ( 0.52%)
Min alloc-odr0-256 204.00 ( 0.00%) 200.00 ( 1.96%)
Min alloc-odr0-512 213.00 ( 0.00%) 212.00 ( 0.47%)
Min alloc-odr0-1024 219.00 ( 0.00%) 219.00 ( 0.00%)
Min alloc-odr0-2048 225.00 ( 0.00%) 225.00 ( 0.00%)
Min alloc-odr0-4096 230.00 ( 0.00%) 231.00 ( -0.43%)
Min alloc-odr0-8192 235.00 ( 0.00%) 234.00 ( 0.43%)
Min alloc-odr0-16384 235.00 ( 0.00%) 234.00 ( 0.43%)
Min free-odr0-1 215.00 ( 0.00%) 191.00 ( 11.16%)
Min free-odr0-2 152.00 ( 0.00%) 136.00 ( 10.53%)
Min free-odr0-4 119.00 ( 0.00%) 107.00 ( 10.08%)
Min free-odr0-8 106.00 ( 0.00%) 96.00 ( 9.43%)
Min free-odr0-16 97.00 ( 0.00%) 87.00 ( 10.31%)
Min free-odr0-32 91.00 ( 0.00%) 83.00 ( 8.79%)
Min free-odr0-64 89.00 ( 0.00%) 81.00 ( 8.99%)
Min free-odr0-128 88.00 ( 0.00%) 80.00 ( 9.09%)
Min free-odr0-256 106.00 ( 0.00%) 95.00 ( 10.38%)
Min free-odr0-512 116.00 ( 0.00%) 111.00 ( 4.31%)
Min free-odr0-1024 125.00 ( 0.00%) 118.00 ( 5.60%)
Min free-odr0-2048 133.00 ( 0.00%) 126.00 ( 5.26%)
Min free-odr0-4096 136.00 ( 0.00%) 130.00 ( 4.41%)
Min free-odr0-8192 138.00 ( 0.00%) 130.00 ( 5.80%)
Min free-odr0-16384 137.00 ( 0.00%) 130.00 ( 5.11%)
There is a sizable boost to the free allocator performance. While there
is an apparent boost on the allocation side, it's likely a co-incidence
or due to the patches slightly reducing cache footprint.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Another year, another round of page allocator optimisations focusing
this time on the alloc and free fast paths. This should be of help to
workloads that are allocator-intensive from kernel space where the cost
of zeroing is not nceessraily incurred.
The series is motivated by the observation that page alloc
microbenchmarks on multiple machines regressed between 3.12.44 and 4.4.
Second, there is discussions before LSF/MM considering the possibility
of adding another page allocator which is potentially hazardous but a
patch series improving performance is better than whining.
After the series is applied, there are still hazards. In the free
paths, the debugging checking and page zone/pageblock lookups dominate
but there was not an obvious solution to that. In the alloc path, the
major contributers are dealing with zonelists, new page preperation, the
fair zone allocation and numerous statistic updates. The fair zone
allocator is removed by the per-node LRU series if that gets merged so
it's nor a major concern at the moment.
On normal userspace benchmarks, there is little impact as the zeroing
cost is significant but it's visible
aim9
4.6.0-rc3 4.6.0-rc3
vanilla deferalloc-v3
Min page_test 828693.33 ( 0.00%) 887060.00 ( 7.04%)
Min brk_test 4847266.67 ( 0.00%) 4966266.67 ( 2.45%)
Min exec_test 1271.00 ( 0.00%) 1275.67 ( 0.37%)
Min fork_test 12371.75 ( 0.00%) 12380.00 ( 0.07%)
The overall impact on a page allocator microbenchmark for a range of orders
and number of pages allocated in a batch is
4.6.0-rc3 4.6.0-rc3
vanilla deferalloc-v3r7
Min alloc-odr0-1 428.00 ( 0.00%) 316.00 ( 26.17%)
Min alloc-odr0-2 314.00 ( 0.00%) 231.00 ( 26.43%)
Min alloc-odr0-4 256.00 ( 0.00%) 192.00 ( 25.00%)
Min alloc-odr0-8 222.00 ( 0.00%) 166.00 ( 25.23%)
Min alloc-odr0-16 207.00 ( 0.00%) 154.00 ( 25.60%)
Min alloc-odr0-32 197.00 ( 0.00%) 148.00 ( 24.87%)
Min alloc-odr0-64 193.00 ( 0.00%) 144.00 ( 25.39%)
Min alloc-odr0-128 191.00 ( 0.00%) 143.00 ( 25.13%)
Min alloc-odr0-256 203.00 ( 0.00%) 153.00 ( 24.63%)
Min alloc-odr0-512 212.00 ( 0.00%) 165.00 ( 22.17%)
Min alloc-odr0-1024 221.00 ( 0.00%) 172.00 ( 22.17%)
Min alloc-odr0-2048 225.00 ( 0.00%) 179.00 ( 20.44%)
Min alloc-odr0-4096 232.00 ( 0.00%) 185.00 ( 20.26%)
Min alloc-odr0-8192 235.00 ( 0.00%) 187.00 ( 20.43%)
Min alloc-odr0-16384 236.00 ( 0.00%) 188.00 ( 20.34%)
Min alloc-odr1-1 519.00 ( 0.00%) 450.00 ( 13.29%)
Min alloc-odr1-2 391.00 ( 0.00%) 336.00 ( 14.07%)
Min alloc-odr1-4 313.00 ( 0.00%) 268.00 ( 14.38%)
Min alloc-odr1-8 277.00 ( 0.00%) 235.00 ( 15.16%)
Min alloc-odr1-16 256.00 ( 0.00%) 218.00 ( 14.84%)
Min alloc-odr1-32 252.00 ( 0.00%) 212.00 ( 15.87%)
Min alloc-odr1-64 244.00 ( 0.00%) 206.00 ( 15.57%)
Min alloc-odr1-128 244.00 ( 0.00%) 207.00 ( 15.16%)
Min alloc-odr1-256 243.00 ( 0.00%) 207.00 ( 14.81%)
Min alloc-odr1-512 245.00 ( 0.00%) 209.00 ( 14.69%)
Min alloc-odr1-1024 248.00 ( 0.00%) 214.00 ( 13.71%)
Min alloc-odr1-2048 253.00 ( 0.00%) 220.00 ( 13.04%)
Min alloc-odr1-4096 258.00 ( 0.00%) 224.00 ( 13.18%)
Min alloc-odr1-8192 261.00 ( 0.00%) 229.00 ( 12.26%)
Min alloc-odr2-1 560.00 ( 0.00%) 753.00 (-34.46%)
Min alloc-odr2-2 424.00 ( 0.00%) 351.00 ( 17.22%)
Min alloc-odr2-4 339.00 ( 0.00%) 393.00 (-15.93%)
Min alloc-odr2-8 298.00 ( 0.00%) 246.00 ( 17.45%)
Min alloc-odr2-16 276.00 ( 0.00%) 227.00 ( 17.75%)
Min alloc-odr2-32 271.00 ( 0.00%) 221.00 ( 18.45%)
Min alloc-odr2-64 264.00 ( 0.00%) 217.00 ( 17.80%)
Min alloc-odr2-128 264.00 ( 0.00%) 217.00 ( 17.80%)
Min alloc-odr2-256 264.00 ( 0.00%) 218.00 ( 17.42%)
Min alloc-odr2-512 269.00 ( 0.00%) 223.00 ( 17.10%)
Min alloc-odr2-1024 279.00 ( 0.00%) 230.00 ( 17.56%)
Min alloc-odr2-2048 283.00 ( 0.00%) 235.00 ( 16.96%)
Min alloc-odr2-4096 285.00 ( 0.00%) 239.00 ( 16.14%)
Min alloc-odr3-1 629.00 ( 0.00%) 505.00 ( 19.71%)
Min alloc-odr3-2 472.00 ( 0.00%) 374.00 ( 20.76%)
Min alloc-odr3-4 383.00 ( 0.00%) 301.00 ( 21.41%)
Min alloc-odr3-8 341.00 ( 0.00%) 266.00 ( 21.99%)
Min alloc-odr3-16 316.00 ( 0.00%) 248.00 ( 21.52%)
Min alloc-odr3-32 308.00 ( 0.00%) 241.00 ( 21.75%)
Min alloc-odr3-64 305.00 ( 0.00%) 241.00 ( 20.98%)
Min alloc-odr3-128 308.00 ( 0.00%) 244.00 ( 20.78%)
Min alloc-odr3-256 317.00 ( 0.00%) 249.00 ( 21.45%)
Min alloc-odr3-512 327.00 ( 0.00%) 256.00 ( 21.71%)
Min alloc-odr3-1024 331.00 ( 0.00%) 261.00 ( 21.15%)
Min alloc-odr3-2048 333.00 ( 0.00%) 266.00 ( 20.12%)
Min alloc-odr4-1 767.00 ( 0.00%) 572.00 ( 25.42%)
Min alloc-odr4-2 578.00 ( 0.00%) 429.00 ( 25.78%)
Min alloc-odr4-4 474.00 ( 0.00%) 346.00 ( 27.00%)
Min alloc-odr4-8 422.00 ( 0.00%) 310.00 ( 26.54%)
Min alloc-odr4-16 399.00 ( 0.00%) 295.00 ( 26.07%)
Min alloc-odr4-32 392.00 ( 0.00%) 293.00 ( 25.26%)
Min alloc-odr4-64 394.00 ( 0.00%) 293.00 ( 25.63%)
Min alloc-odr4-128 405.00 ( 0.00%) 305.00 ( 24.69%)
Min alloc-odr4-256 417.00 ( 0.00%) 319.00 ( 23.50%)
Min alloc-odr4-512 425.00 ( 0.00%) 326.00 ( 23.29%)
Min alloc-odr4-1024 426.00 ( 0.00%) 329.00 ( 22.77%)
Min free-odr0-1 216.00 ( 0.00%) 178.00 ( 17.59%)
Min free-odr0-2 152.00 ( 0.00%) 125.00 ( 17.76%)
Min free-odr0-4 120.00 ( 0.00%) 99.00 ( 17.50%)
Min free-odr0-8 106.00 ( 0.00%) 85.00 ( 19.81%)
Min free-odr0-16 97.00 ( 0.00%) 80.00 ( 17.53%)
Min free-odr0-32 92.00 ( 0.00%) 76.00 ( 17.39%)
Min free-odr0-64 89.00 ( 0.00%) 74.00 ( 16.85%)
Min free-odr0-128 89.00 ( 0.00%) 73.00 ( 17.98%)
Min free-odr0-256 107.00 ( 0.00%) 90.00 ( 15.89%)
Min free-odr0-512 117.00 ( 0.00%) 108.00 ( 7.69%)
Min free-odr0-1024 125.00 ( 0.00%) 118.00 ( 5.60%)
Min free-odr0-2048 132.00 ( 0.00%) 125.00 ( 5.30%)
Min free-odr0-4096 135.00 ( 0.00%) 130.00 ( 3.70%)
Min free-odr0-8192 137.00 ( 0.00%) 130.00 ( 5.11%)
Min free-odr0-16384 137.00 ( 0.00%) 131.00 ( 4.38%)
Min free-odr1-1 318.00 ( 0.00%) 289.00 ( 9.12%)
Min free-odr1-2 228.00 ( 0.00%) 207.00 ( 9.21%)
Min free-odr1-4 182.00 ( 0.00%) 165.00 ( 9.34%)
Min free-odr1-8 163.00 ( 0.00%) 146.00 ( 10.43%)
Min free-odr1-16 151.00 ( 0.00%) 135.00 ( 10.60%)
Min free-odr1-32 146.00 ( 0.00%) 129.00 ( 11.64%)
Min free-odr1-64 145.00 ( 0.00%) 130.00 ( 10.34%)
Min free-odr1-128 148.00 ( 0.00%) 134.00 ( 9.46%)
Min free-odr1-256 148.00 ( 0.00%) 137.00 ( 7.43%)
Min free-odr1-512 151.00 ( 0.00%) 140.00 ( 7.28%)
Min free-odr1-1024 154.00 ( 0.00%) 143.00 ( 7.14%)
Min free-odr1-2048 156.00 ( 0.00%) 144.00 ( 7.69%)
Min free-odr1-4096 156.00 ( 0.00%) 142.00 ( 8.97%)
Min free-odr1-8192 156.00 ( 0.00%) 140.00 ( 10.26%)
Min free-odr2-1 361.00 ( 0.00%) 457.00 (-26.59%)
Min free-odr2-2 258.00 ( 0.00%) 224.00 ( 13.18%)
Min free-odr2-4 208.00 ( 0.00%) 223.00 ( -7.21%)
Min free-odr2-8 185.00 ( 0.00%) 160.00 ( 13.51%)
Min free-odr2-16 173.00 ( 0.00%) 149.00 ( 13.87%)
Min free-odr2-32 166.00 ( 0.00%) 145.00 ( 12.65%)
Min free-odr2-64 166.00 ( 0.00%) 146.00 ( 12.05%)
Min free-odr2-128 169.00 ( 0.00%) 148.00 ( 12.43%)
Min free-odr2-256 170.00 ( 0.00%) 152.00 ( 10.59%)
Min free-odr2-512 177.00 ( 0.00%) 156.00 ( 11.86%)
Min free-odr2-1024 182.00 ( 0.00%) 162.00 ( 10.99%)
Min free-odr2-2048 181.00 ( 0.00%) 160.00 ( 11.60%)
Min free-odr2-4096 180.00 ( 0.00%) 159.00 ( 11.67%)
Min free-odr3-1 431.00 ( 0.00%) 367.00 ( 14.85%)
Min free-odr3-2 306.00 ( 0.00%) 259.00 ( 15.36%)
Min free-odr3-4 249.00 ( 0.00%) 208.00 ( 16.47%)
Min free-odr3-8 224.00 ( 0.00%) 186.00 ( 16.96%)
Min free-odr3-16 208.00 ( 0.00%) 176.00 ( 15.38%)
Min free-odr3-32 206.00 ( 0.00%) 174.00 ( 15.53%)
Min free-odr3-64 210.00 ( 0.00%) 178.00 ( 15.24%)
Min free-odr3-128 215.00 ( 0.00%) 182.00 ( 15.35%)
Min free-odr3-256 224.00 ( 0.00%) 189.00 ( 15.62%)
Min free-odr3-512 232.00 ( 0.00%) 195.00 ( 15.95%)
Min free-odr3-1024 230.00 ( 0.00%) 195.00 ( 15.22%)
Min free-odr3-2048 229.00 ( 0.00%) 193.00 ( 15.72%)
Min free-odr4-1 561.00 ( 0.00%) 439.00 ( 21.75%)
Min free-odr4-2 418.00 ( 0.00%) 318.00 ( 23.92%)
Min free-odr4-4 339.00 ( 0.00%) 269.00 ( 20.65%)
Min free-odr4-8 299.00 ( 0.00%) 239.00 ( 20.07%)
Min free-odr4-16 289.00 ( 0.00%) 234.00 ( 19.03%)
Min free-odr4-32 291.00 ( 0.00%) 235.00 ( 19.24%)
Min free-odr4-64 298.00 ( 0.00%) 238.00 ( 20.13%)
Min free-odr4-128 308.00 ( 0.00%) 251.00 ( 18.51%)
Min free-odr4-256 321.00 ( 0.00%) 267.00 ( 16.82%)
Min free-odr4-512 327.00 ( 0.00%) 269.00 ( 17.74%)
Min free-odr4-1024 326.00 ( 0.00%) 271.00 ( 16.87%)
Min total-odr0-1 644.00 ( 0.00%) 494.00 ( 23.29%)
Min total-odr0-2 466.00 ( 0.00%) 356.00 ( 23.61%)
Min total-odr0-4 376.00 ( 0.00%) 291.00 ( 22.61%)
Min total-odr0-8 328.00 ( 0.00%) 251.00 ( 23.48%)
Min total-odr0-16 304.00 ( 0.00%) 234.00 ( 23.03%)
Min total-odr0-32 289.00 ( 0.00%) 224.00 ( 22.49%)
Min total-odr0-64 282.00 ( 0.00%) 218.00 ( 22.70%)
Min total-odr0-128 280.00 ( 0.00%) 216.00 ( 22.86%)
Min total-odr0-256 310.00 ( 0.00%) 243.00 ( 21.61%)
Min total-odr0-512 329.00 ( 0.00%) 273.00 ( 17.02%)
Min total-odr0-1024 346.00 ( 0.00%) 290.00 ( 16.18%)
Min total-odr0-2048 357.00 ( 0.00%) 304.00 ( 14.85%)
Min total-odr0-4096 367.00 ( 0.00%) 315.00 ( 14.17%)
Min total-odr0-8192 372.00 ( 0.00%) 317.00 ( 14.78%)
Min total-odr0-16384 373.00 ( 0.00%) 319.00 ( 14.48%)
Min total-odr1-1 838.00 ( 0.00%) 739.00 ( 11.81%)
Min total-odr1-2 619.00 ( 0.00%) 543.00 ( 12.28%)
Min total-odr1-4 495.00 ( 0.00%) 433.00 ( 12.53%)
Min total-odr1-8 440.00 ( 0.00%) 382.00 ( 13.18%)
Min total-odr1-16 407.00 ( 0.00%) 353.00 ( 13.27%)
Min total-odr1-32 398.00 ( 0.00%) 341.00 ( 14.32%)
Min total-odr1-64 389.00 ( 0.00%) 336.00 ( 13.62%)
Min total-odr1-128 392.00 ( 0.00%) 341.00 ( 13.01%)
Min total-odr1-256 391.00 ( 0.00%) 344.00 ( 12.02%)
Min total-odr1-512 396.00 ( 0.00%) 349.00 ( 11.87%)
Min total-odr1-1024 402.00 ( 0.00%) 357.00 ( 11.19%)
Min total-odr1-2048 409.00 ( 0.00%) 364.00 ( 11.00%)
Min total-odr1-4096 414.00 ( 0.00%) 366.00 ( 11.59%)
Min total-odr1-8192 417.00 ( 0.00%) 369.00 ( 11.51%)
Min total-odr2-1 921.00 ( 0.00%) 1210.00 (-31.38%)
Min total-odr2-2 682.00 ( 0.00%) 576.00 ( 15.54%)
Min total-odr2-4 547.00 ( 0.00%) 616.00 (-12.61%)
Min total-odr2-8 483.00 ( 0.00%) 406.00 ( 15.94%)
Min total-odr2-16 449.00 ( 0.00%) 376.00 ( 16.26%)
Min total-odr2-32 437.00 ( 0.00%) 366.00 ( 16.25%)
Min total-odr2-64 431.00 ( 0.00%) 363.00 ( 15.78%)
Min total-odr2-128 433.00 ( 0.00%) 365.00 ( 15.70%)
Min total-odr2-256 434.00 ( 0.00%) 371.00 ( 14.52%)
Min total-odr2-512 446.00 ( 0.00%) 379.00 ( 15.02%)
Min total-odr2-1024 461.00 ( 0.00%) 392.00 ( 14.97%)
Min total-odr2-2048 464.00 ( 0.00%) 395.00 ( 14.87%)
Min total-odr2-4096 465.00 ( 0.00%) 398.00 ( 14.41%)
Min total-odr3-1 1060.00 ( 0.00%) 872.00 ( 17.74%)
Min total-odr3-2 778.00 ( 0.00%) 633.00 ( 18.64%)
Min total-odr3-4 632.00 ( 0.00%) 510.00 ( 19.30%)
Min total-odr3-8 565.00 ( 0.00%) 452.00 ( 20.00%)
Min total-odr3-16 524.00 ( 0.00%) 424.00 ( 19.08%)
Min total-odr3-32 514.00 ( 0.00%) 415.00 ( 19.26%)
Min total-odr3-64 515.00 ( 0.00%) 419.00 ( 18.64%)
Min total-odr3-128 523.00 ( 0.00%) 426.00 ( 18.55%)
Min total-odr3-256 541.00 ( 0.00%) 438.00 ( 19.04%)
Min total-odr3-512 559.00 ( 0.00%) 451.00 ( 19.32%)
Min total-odr3-1024 561.00 ( 0.00%) 456.00 ( 18.72%)
Min total-odr3-2048 562.00 ( 0.00%) 459.00 ( 18.33%)
Min total-odr4-1 1328.00 ( 0.00%) 1011.00 ( 23.87%)
Min total-odr4-2 997.00 ( 0.00%) 747.00 ( 25.08%)
Min total-odr4-4 813.00 ( 0.00%) 615.00 ( 24.35%)
Min total-odr4-8 721.00 ( 0.00%) 550.00 ( 23.72%)
Min total-odr4-16 689.00 ( 0.00%) 529.00 ( 23.22%)
Min total-odr4-32 683.00 ( 0.00%) 528.00 ( 22.69%)
Min total-odr4-64 692.00 ( 0.00%) 531.00 ( 23.27%)
Min total-odr4-128 713.00 ( 0.00%) 556.00 ( 22.02%)
Min total-odr4-256 738.00 ( 0.00%) 586.00 ( 20.60%)
Min total-odr4-512 753.00 ( 0.00%) 595.00 ( 20.98%)
Min total-odr4-1024 752.00 ( 0.00%) 600.00 ( 20.21%)
This patch (of 27):
order-0 pages by definition cannot be compound so avoid the check in the
fast path for those pages.
[akpm@linux-foundation.org: use unlikely(order) in free_pages_prepare(), per Vlastimil]
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Right now the oom reaper will clear TIF_MEMDIE only for tasks which were
successfully reaped. This is the safest option because we know that
such an oom victim would only block forward progress of the oom killer
without a good reason because it is highly unlikely it would release
much more memory. Basically most of its memory has been already torn
down.
We can relax this assumption to catch more corner cases though.
The first obvious one is when the oom victim clears its mm and gets
stuck later on. oom_reaper would back of on find_lock_task_mm returning
NULL. We can safely try to clear TIF_MEMDIE in this case because such a
task would be ignored by the oom killer anyway. The flag would be
cleared by that time already most of the time anyway.
The less obvious one is when the oom reaper fails due to mmap_sem
contention. Even if we clear TIF_MEMDIE for this task then it is not
very likely that we would select another task too easily because we
haven't reaped the last victim and so it would be still the #1
candidate. There is a rare race condition possible when the current
victim terminates before the next select_bad_process but considering
that oom_reap_task had retried several times before giving up then this
sounds like a borderline thing.
After this patch we should have a guarantee that the OOM killer will not
be block for unbounded amount of time for most cases.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Raushaniya Maksudova <rmaksudova@parallels.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
If either the current task is already killed or PF_EXITING or a selected
task is PF_EXITING then the oom killer is suppressed and so is the oom
reaper. This patch adds try_oom_reaper which checks the given task and
queues it for the oom reaper if that is safe to be done meaning that the
task doesn't share the mm with an alive process.
This might help to release the memory pressure while the task tries to
exit.
[akpm@linux-foundation.org: fix nommu build]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Raushaniya Maksudova <rmaksudova@parallels.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
__alloc_pages_may_oom is the central place to decide when the
out_of_memory should be invoked. This is a good approach for most
checks there because they are page allocator specific and the allocation
fails right after for all of them.
The notable exception is GFP_NOFS context which is faking
did_some_progress and keep the page allocator looping even though there
couldn't have been any progress from the OOM killer. This patch doesn't
change this behavior because we are not ready to allow those allocation
requests to fail yet (and maybe we will face the reality that we will
never manage to safely fail these request). Instead __GFP_FS check is
moved down to out_of_memory and prevent from OOM victim selection there.
There are two reasons for that
- OOM notifiers might release some memory even from this context
as none of the registered notifier seems to be FS related
- this might help a dying thread to get an access to memory
reserves and move on which will make the behavior more
consistent with the case when the task gets killed from a
different context.
Keep a comment in __alloc_pages_may_oom to make sure we do not forget
how GFP_NOFS is special and that we really want to do something about
it.
Note to the current oom_notifier users:
The observable difference for you is that oom notifiers cannot depend on
any fs locks because we could deadlock. Not that this would be allowed
today because that would just lockup machine in most of the cases and
ruling out the OOM killer along the way. Another difference is that
callbacks might be invoked sooner now because GFP_NOFS is a weaker
reclaim context and so there could be reclaimable memory which is just
not reachable now. That would require GFP_NOFS only loads which are
really rare and more importantly the observable result would be dropping
of reconstructible object and potential performance drop which is not
such a big deal when we are struggling to fulfill other important
allocation requests.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Raushaniya Maksudova <rmaksudova@parallels.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE specifies the default value for the
memory hotplug onlining policy. Add a command line parameter to make it
possible to override the default. It may come handy for debug and
testing purposes.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Lennart Poettering <lennart@poettering.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This patchset continues the work I started with commit 31bc3858ea3e
("memory-hotplug: add automatic onlining policy for the newly added
memory").
Initially I was going to stop there and bring the policy setting logic
to userspace. I met two issues on this way:
1) It is possible to have memory hotplugged at boot (e.g. with QEMU).
These blocks stay offlined if we turn the onlining policy on by
userspace.
2) My attempt to bring this policy setting to systemd failed, systemd
maintainers suggest to change the default in kernel or ... to use
tmpfiles.d to alter the policy (which looks like a hack to me):
https://github.com/systemd/systemd/pull/2938
Here I suggest to add a config option to set the default value for the
policy and a kernel command line parameter to make the override.
This patch (of 2):
Introduce config option to set the default value for memory hotplug
onlining policy (/sys/devices/system/memory/auto_online_blocks). The
reason one would want to turn this option on are to have early onlining
for hotpluggable memory available at boot and to not require any
userspace actions to make memory hotplug work.
[akpm@linux-foundation.org: tweak Kconfig text]
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Lennart Poettering <lennart@poettering.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Whatever huge pagecache implementation we go with, file rmap locking
must be added to anon rmap locking, when mremap's move_page_tables()
finds a pmd_trans_huge pmd entry: a simple change, let's do it now.
Factor out take_rmap_locks() and drop_rmap_locks() to handle the locking
for make move_ptes() and move_page_tables(), and delete the
VM_BUG_ON_VMA which rejected vm_file and required anon_vma.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Remove move_huge_pmd()'s redundant new_vma arg: all it was used for was
a VM_NOHUGEPAGE check on new_vma flags, but the new_vma is cloned from
the old vma, so a trans_huge_pmd in the new_vma will be as acceptable as
it was in the old vma, alignment and size permitting.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Provide /proc/sys/vm/stat_refresh to force an immediate update of
per-cpu into global vmstats: useful to avoid a sleep(2) or whatever
before checking counts when testing. Originally added to work around a
bug which left counts stranded indefinitely on a cpu going idle (an
inaccuracy magnified when small below-batch numbers represent "huge"
amounts of memory), but I believe that bug is now fixed: nonetheless,
this is still a useful knob.
Its schedule_on_each_cpu() is probably too expensive just to fold into
reading /proc/meminfo itself: give this mode 0600 to prevent abuse.
Allow a write or a read to do the same: nothing to read, but "grep -h
Shmem /proc/sys/vm/stat_refresh /proc/meminfo" is convenient. Oh, and
since global_page_state() itself is careful to disguise any underflow as
0, hack in an "Invalid argument" and pr_warn() if a counter is negative
after the refresh - this helped to fix a misaccounting of
NR_ISOLATED_FILE in my migration code.
But on recent kernels, I find that NR_ALLOC_BATCH and NR_PAGES_SCANNED
often go negative some of the time. I have not yet worked out why, but
have no evidence that it's actually harmful. Punt for the moment by
just ignoring the anomaly on those.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Although shmem_fault() has been careful to count a major fault to vm_mm,
shmem_getpage_gfp() has been careless in charging a remote access fault
to current->mm owner's memcg instead of to vma->vm_mm owner's memcg:
that is inconsistent with all the mem_cgroup charging on remote access
faults in mm/memory.c.
Fix it by passing fault_mm along with fault_type to
shmem_get_page_gfp(); but in that case, now knowing the right mm, it's
better for it to handle the PGMAJFAULT updates itself.
And let's keep this clutter out of most callers' way: change the common
shmem_getpage() wrapper to hide fault_mm and fault_type as well as gfp.
Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Make a few cleanups in mm/shmem.c, before going on to complicate it.
shmem_alloc_page() will become more complicated: we can't afford to to
have that complication duplicated between a CONFIG_NUMA version and a
!CONFIG_NUMA version, so rearrange the #ifdef'ery there to yield a
single shmem_swapin() and a single shmem_alloc_page().
Yes, it's a shame to inflict the horrid pseudo-vma on non-NUMA
configurations, but eliminating it is a larger cleanup: I have an
alloc_pages_mpol() patchset not yet ready - mpol handling is subtle and
bug-prone, and changed yet again since my last version.
Move __SetPageLocked, __SetPageSwapBacked from shmem_getpage_gfp() to
shmem_alloc_page(): that SwapBacked flag will be useful in future, to
help to distinguish different cases appropriately.
And the SGP_DIRTY variant of SGP_CACHE is hard to understand and of
little use (IIRC it dates back to when shmem_getpage() returned the page
unlocked): kill it and do the necessary in shmem_file_read_iter().
But an arm64 build then complained that info may be uninitialized (where
shmem_getpage_gfp() deletes a freshly alloced page beyond eof), and
advancing to an "sgp <= SGP_CACHE" test jogged it back to reality.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
v3.16 commit 07a427884348 ("mm: shmem: avoid atomic operation during
shmem_getpage_gfp") rightly replaced one instance of SetPageSwapBacked
by __SetPageSwapBacked, pointing out that the newly allocated page is
not yet visible to other users (except speculative get_page_unless_zero-
ers, who may not update page flags before their further checks).
That was part of a series in which Mel was focused on tmpfs profiles:
but almost all SetPageSwapBacked uses can be so optimized, with the same
justification.
Remove ClearPageSwapBacked from __read_swap_cache_async() error path:
it's not an error to free a page with PG_swapbacked set.
Follow a convention of __SetPageLocked, __SetPageSwapBacked instead of
doing it differently in different places; but that's for tidiness - if
the ordering actually mattered, we should not be using the __variants.
There's probably scope for further __SetPageFlags in other places, but
SwapBacked is the one I'm interested in at the moment.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Reviewed-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Konstantin Khlebnikov pointed out (nearly four years ago, when lumpy
reclaim was removed) that lru_size can be updated by -nr_taken once per
call to isolate_lru_pages(), instead of page by page.
Update it inside isolate_lru_pages(), or at its two callsites? I chose
to update it at the callsites, rearranging and grouping the updates by
nr_taken and nr_scanned together in both.
With one exception, mem_cgroup_update_lru_size(,lru,) is then used where
__mod_zone_page_state(,NR_LRU_BASE+lru,) is used; and we shall be adding
some more calls in a future commit. Make the code a little smaller and
simpler by incorporating stat update in lru_size update.
The exception was move_active_pages_to_lru(), which aggregated the
pgmoved stat update separately from the individual lru_size updates; but
I still think this a simplification worth making.
However, the __mod_zone_page_state is not peculiar to mem_cgroups: so
better use the name update_lru_size, calls mem_cgroup_update_lru_size
when CONFIG_MEMCG.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Though debug kernels have a VM_BUG_ON to help protect from misaccounting
lru_size, non-debug kernels are liable to wrap it around: and then the
vast unsigned long size draws page reclaim into a loop of repeatedly
doing nothing on an empty list, without even a cond_resched().
That soft lockup looks confusingly like an over-busy reclaim scenario,
with lots of contention on the lru_lock in shrink_inactive_list(): yet
has a totally different origin.
Help differentiate with a custom warning in
mem_cgroup_update_lru_size(), even in non-debug kernels; and reset the
size to avoid the lockup. But the particular bug which suggested this
change was mine alone, and since fixed.
Make it a WARN_ONCE: the first occurrence is the most informative, a
flurry may follow, yet even when rate-limited little more is learnt.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Nobody uses it.
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
node_page_state() manually adds statistics per each zone and returns
total value for all zones. Whenever we add a new zone, we need to
consider this function and it's really troublesome. Make it handle all
zones by itself.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
nr_free_highpages() manually adds statistics per each highmem zone and
returns a total value for them. Whenever we add a new highmem zone, we
need to consider this function and it's really troublesome. Make it
handle all highmem zones by itself.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
ZONE_MOVABLE could be treated as highmem so we need to consider it for
accurate statistics. And, in following patches, ZONE_CMA will be
introduced and it can be treated as highmem, too. So, instead of
manually adding stat of ZONE_MOVABLE, looping all zones and check
whether the zone is highmem or not and add stat of the zone which can be
treated as highmem.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
ZONE_MOVABLE could be treated as highmem so we need to consider it for
accurate calculation of dirty pages. And, in following patches,
ZONE_CMA will be introduced and it can be treated as highmem, too. So,
instead of manually adding stat of ZONE_MOVABLE, looping all zones and
check whether the zone is highmem or not and add stat of the zone which
can be treated as highmem.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
There is a system thats node's pfns are overlapped as follows:
-----pfn-------->
N0 N1 N2 N0 N1 N2
Therefore, we need to care this overlapping when iterating pfn range.
mark_free_pages() iterates requested zone's pfn range and unset all
range's bitmap first. And then it marks freepages in a zone to the
bitmap. If there is an overlapping zone, above unset could clear
previous marked bit and reference to this bitmap in the future will
cause the problem. To prevent it, this patch adds a zone check in
mark_free_pages().
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
There is a system thats node's pfns are overlapped as follows:
-----pfn-------->
N0 N1 N2 N0 N1 N2
Therefore, we need to care this overlapping when iterating pfn range.
There are one place in page_owner.c that iterates pfn range and it
doesn't consider this overlapping. Add it.
Without this patch, above system could over count early allocated page
number before page_owner is activated.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
There is a system thats node's pfns are overlapped as follows:
-----pfn-------->
N0 N1 N2 N0 N1 N2
Therefore, we need to care this overlapping when iterating pfn range.
There are two places in vmstat.c that iterates pfn range and they don't
consider this overlapping. Add it.
Without this patch, above system could over count pageblock number on a
zone.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
__offline_isolated_pages() and test_pages_isolated() are used by memory
hotplug. These functions require that range is in a single zone but
there is no code to do this because memory hotplug checks it before
calling these functions. To avoid confusing future user of these
functions, this patch adds comments to them.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This patchset deals with some problematic sites that iterate pfn ranges.
There is a system thats node's pfns are overlapped as follows:
-----pfn-------->
N0 N1 N2 N0 N1 N2
Therefore, we need to take care of this overlapping when iterating pfn
range.
I audit many iterating sites that uses pfn_valid(), pfn_valid_within(),
zone_start_pfn and etc. and others looks safe to me. This is a
preparation step for a new CMA implementation, ZONE_CMA
(https://lkml.org/lkml/2015/2/12/95), because it would be easily
overlapped with other zones. But, zone overlap check is also needed for
the general case so I send it separately.
This patch (of 5):
alloc_gigantic_page() uses alloc_contig_range() and this requires that
the requested range is in a single zone. To satisfy this requirement,
add this check to pfn_range_valid_gigantic().
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
It's huge. Uninlining it saves 206 bytes per callsite. Shaves 4924
bytes from the x86_64 allmodconfig vmlinux.
[akpm@linux-foundation.org: coding-style fixes]
Cc: Steve Capper <steve.capper@arm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The goal of direct compaction is to quickly make a high-order page
available for the pending allocation. Within an aligned block of pages
of desired order, a single allocated page that cannot be isolated for
migration means that the block cannot fully merge to a buddy page that
would satisfy the allocation request. Therefore we can reduce the
allocation stall by skipping the rest of the block immediately on
isolation failure. For async compaction, this also means a higher
chance of succeeding until it detects contention.
We however shouldn't completely sacrifice the second objective of
compaction, which is to reduce overal long-term memory fragmentation.
As a compromise, perform the eager skipping only in direct async
compaction, while sync compaction (including kcompactd) remains
thorough.
Testing was done using stress-highalloc from mmtests, configured for
order-4 GFP_KERNEL allocations:
4.6-rc1 4.6-rc1
before after
Success 1 Min 24.00 ( 0.00%) 27.00 (-12.50%)
Success 1 Mean 30.20 ( 0.00%) 31.60 ( -4.64%)
Success 1 Max 37.00 ( 0.00%) 35.00 ( 5.41%)
Success 2 Min 42.00 ( 0.00%) 32.00 ( 23.81%)
Success 2 Mean 44.00 ( 0.00%) 44.80 ( -1.82%)
Success 2 Max 48.00 ( 0.00%) 52.00 ( -8.33%)
Success 3 Min 91.00 ( 0.00%) 92.00 ( -1.10%)
Success 3 Mean 92.20 ( 0.00%) 92.80 ( -0.65%)
Success 3 Max 94.00 ( 0.00%) 93.00 ( 1.06%)
We can see that success rates are unaffected by the skipping.
4.6-rc1 4.6-rc1
before after
User 2587.42 2566.53
System 482.89 471.20
Elapsed 1395.68 1382.00
Times are not so useful metric for this benchmark as main portion is the
interfering kernel builds, but results do hint at reduced system times.
4.6-rc1 4.6-rc1
before after
Direct pages scanned 163614 159608
Kswapd pages scanned 2070139 2078790
Kswapd pages reclaimed 2061707 2069757
Direct pages reclaimed 163354 159505
Reduced direct reclaim was unintended, but could be explained by more
successful first attempt at (async) direct compaction, which is
attempted before the first reclaim attempt in __alloc_pages_slowpath().
Compaction stalls 33052 39853
Compaction success 12121 19773
Compaction failures 20931 20079
Compaction is indeed more successful, and thus less likely to get
deferred, so there are also more direct compaction stalls.
Page migrate success 3781876 3326819
Page migrate failure 45817 41774
Compaction pages isolated 7868232 6941457
Compaction migrate scanned 168160492 127269354
Compaction migrate prescanned 0 0
Compaction free scanned 2522142582 2326342620
Compaction free direct alloc 0 0
Compaction free dir. all. miss 0 0
Compaction cost 5252 4476
The patch reduces migration scanned pages by 25% thanks to the eager
skipping.
[hughd@google.com: prevent nr_isolated_* from going negative]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Compaction drains the local pcplists each time migration scanner moves
away from a cc->order aligned block where it isolated pages for
migration, so that the pages freed by migrations can merge into higher
orders.
The detection is currently coarser than it could be. The
cc->last_migrated_pfn variable should track the lowest pfn that was
isolated for migration. But it is set to the pfn where
isolate_migratepages_block() starts scanning, which is typically the
first pfn of the pageblock. There, the scanner might fail to isolate
several order-aligned blocks, and then isolate COMPACT_CLUSTER_MAX in
another block. This would cause the pcplists drain to be performed,
although the scanner didn't yet finish the block where it isolated from.
This patch thus makes cc->last_migrated_pfn handling more accurate by
setting it to the pfn of an actually isolated page in
isolate_migratepages_block(). Although practical effects of this patch
are likely low, it arguably makes the intent of the code more obvious.
Also the next patch will make async direct compaction skip blocks more
aggressively, and draining pcplists due to skipped blocks is wasteful.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Compaction code has accumulated numerous instances of manual
calculations of the first (inclusive) and last (exclusive) pfn of a
pageblock (or a smaller block of given order), given a pfn within the
pageblock.
Wrap these calculations by introducing pageblock_start_pfn(pfn) and
pageblock_end_pfn(pfn) macros.
[vbabka@suse.cz: fix crash in get_pfnblock_flags_mask() from isolate_freepages():]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This check effectively catches anon vma hierarchy inconsistence and some
vma corruptions. It was effective for catching corner cases in anon vma
reusing logic. For now this code seems stable so check could be hidden
under CONFIG_DEBUG_VM and replaced with WARN because it's not so fatal.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Suggested-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This code was pretty obscure and was relying upon obscure side-effects
of next_node(-1, ...) and was relying upon NUMA_NO_NODE being equal to
-1.
Clean that all up and document the function's intent.
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Instead of open-coding it.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
__free_pages_boot_core has parameter pfn which is not used at all.
Remove it.
Signed-off-by: Li Zhang <zhlcindy@linux.vnet.ibm.com>
Reviewed-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
> The comment seems to have not much to do with the code?
I guess the comment tries to say that the code path is triggered when we
charge the page which happens _before_ it is added to the LRU list and
so last_scanned_node might contain the stale data.
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Make is_mem_section_removable() return bool to improve readability due
to this particular function only using either one or zero as its return
value.
Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
When any unsupported hugepage size is specified, 'hugepagesz=' and
'hugepages=' should be ignored during command line parsing until any
supported hugepage size is found. But currently incorrect number of
hugepages are allocated when unsupported size is specified as it fails
to ignore the 'hugepages=' command.
Test case:
Note that this is specific to x86 architecture.
Boot the kernel with command line option 'hugepagesz=256M hugepages=X'.
After boot, dmesg output shows that X number of hugepages of the size 2M
is pre-allocated instead of 0.
So, to handle such command line options, introduce new routine
hugetlb_bad_size. The routine hugetlb_bad_size sets the global variable
parsed_valid_hugepagesz. We are using parsed_valid_hugepagesz to save
the state when unsupported hugepagesize is found so that we can ignore
the 'hugepages=' parameters after that and then reset the variable when
supported hugepage size is found.
The routine hugetlb_bad_size can be called while setting 'hugepagesz='
parameter in an architecture specific code.
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
It was observed that minimum size accounting associated with the
hugetlbfs min_size mount option may not perform optimally and as
expected. As huge pages/reservations are released from the filesystem
and given back to the global pools, they are reserved for subsequent
filesystem use as long as the subpool reserved count is less than
subpool minimum size. It does not take into account used pages within
the filesystem. The filesystem size limits are not exceeded and this is
technically not a bug. However, better behavior would be to wait for
the number of used pages/reservations associated with the filesystem to
drop below the minimum size before taking reservations to satisfy
minimum size.
An optimization is also made to the hugepage_subpool_get_pages() routine
which is called when pages/reservations are allocated. This does not
change behavior, but simply avoids the accounting if all reservations
have already been taken (subpool reserved count == 0).
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Lots of code does
node = next_node(node, XXX);
if (node == MAX_NUMNODES)
node = first_node(XXX);
so create next_node_in() to do this and use it in various places.
[mhocko@suse.com: use next_node_in() helper]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Hui Zhu <zhuhui@xiaomi.com>
Cc: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Many developers already know that field for reference count of the
struct page is _count and atomic type. They would try to handle it
directly and this could break the purpose of page reference count
tracepoint. To prevent direct _count modification, this patch rename it
to _refcount and add warning message on the code. After that, developer
who need to handle reference count will find that field should not be
accessed directly.
[akpm@linux-foundation.org: fix comments, per Vlastimil]
[akpm@linux-foundation.org: Documentation/vm/transhuge.txt too]
[sfr@canb.auug.org.au: sync ethernet driver changes]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sunil Goutham <sgoutham@cavium.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Manish Chopra <manish.chopra@qlogic.com>
Cc: Yuval Mintz <yuval.mintz@qlogic.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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page_reference manipulation functions are introduced to track down
reference count change of the page. Use it instead of direct
modification of _count.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sunil Goutham <sgoutham@cavium.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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/sys/kernel/slab/xx/defrag_ratio should be remote_node_defrag_ratio.
Link: http://lkml.kernel.org/r/1463449242-5366-1-git-send-email-lip@dtdream.com
Signed-off-by: Li Peng <lip@dtdream.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Now we have IS_ENABLED helper to check if a Kconfig option is enabled or
not, so ZONE_DMA_FLAG sounds no longer useful.
And, the use of ZONE_DMA_FLAG in slab looks pointless according to the
comment [1] from Johannes Weiner, so remove them and ORing passed in
flags with the cache gfp flags has been done in kmem_getpages().
[1] https://lkml.org/lkml/2014/9/25/553
Link: http://lkml.kernel.org/r/1462381297-11009-1-git-send-email-yang.shi@linaro.org
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Provides an optional config (CONFIG_SLAB_FREELIST_RANDOM) to randomize
the SLAB freelist. The list is randomized during initialization of a
new set of pages. The order on different freelist sizes is pre-computed
at boot for performance. Each kmem_cache has its own randomized
freelist. Before pre-computed lists are available freelists are
generated dynamically. This security feature reduces the predictability
of the kernel SLAB allocator against heap overflows rendering attacks
much less stable.
For example this attack against SLUB (also applicable against SLAB)
would be affected:
https://jon.oberheide.org/blog/2010/09/10/linux-kernel-can-slub-overflow/
Also, since v4.6 the freelist was moved at the end of the SLAB. It
means a controllable heap is opened to new attacks not yet publicly
discussed. A kernel heap overflow can be transformed to multiple
use-after-free. This feature makes this type of attack harder too.
To generate entropy, we use get_random_bytes_arch because 0 bits of
entropy is available in the boot stage. In the worse case this function
will fallback to the get_random_bytes sub API. We also generate a shift
random number to shift pre-computed freelist for each new set of pages.
The config option name is not specific to the SLAB as this approach will
be extended to other allocators like SLUB.
Performance results highlighted no major changes:
Hackbench (running 90 10 times):
Before average: 0.0698
After average: 0.0663 (-5.01%)
slab_test 1 run on boot. Difference only seen on the 2048 size test
being the worse case scenario covered by freelist randomization. New
slab pages are constantly being created on the 10000 allocations.
Variance should be mainly due to getting new pages every few
allocations.
Before:
Single thread testing
=====================
1. Kmalloc: Repeatedly allocate then free test
10000 times kmalloc(8) -> 99 cycles kfree -> 112 cycles
10000 times kmalloc(16) -> 109 cycles kfree -> 140 cycles
10000 times kmalloc(32) -> 129 cycles kfree -> 137 cycles
10000 times kmalloc(64) -> 141 cycles kfree -> 141 cycles
10000 times kmalloc(128) -> 152 cycles kfree -> 148 cycles
10000 times kmalloc(256) -> 195 cycles kfree -> 167 cycles
10000 times kmalloc(512) -> 257 cycles kfree -> 199 cycles
10000 times kmalloc(1024) -> 393 cycles kfree -> 251 cycles
10000 times kmalloc(2048) -> 649 cycles kfree -> 228 cycles
10000 times kmalloc(4096) -> 806 cycles kfree -> 370 cycles
10000 times kmalloc(8192) -> 814 cycles kfree -> 411 cycles
10000 times kmalloc(16384) -> 892 cycles kfree -> 455 cycles
2. Kmalloc: alloc/free test
10000 times kmalloc(8)/kfree -> 121 cycles
10000 times kmalloc(16)/kfree -> 121 cycles
10000 times kmalloc(32)/kfree -> 121 cycles
10000 times kmalloc(64)/kfree -> 121 cycles
10000 times kmalloc(128)/kfree -> 121 cycles
10000 times kmalloc(256)/kfree -> 119 cycles
10000 times kmalloc(512)/kfree -> 119 cycles
10000 times kmalloc(1024)/kfree -> 119 cycles
10000 times kmalloc(2048)/kfree -> 119 cycles
10000 times kmalloc(4096)/kfree -> 121 cycles
10000 times kmalloc(8192)/kfree -> 119 cycles
10000 times kmalloc(16384)/kfree -> 119 cycles
After:
Single thread testing
=====================
1. Kmalloc: Repeatedly allocate then free test
10000 times kmalloc(8) -> 130 cycles kfree -> 86 cycles
10000 times kmalloc(16) -> 118 cycles kfree -> 86 cycles
10000 times kmalloc(32) -> 121 cycles kfree -> 85 cycles
10000 times kmalloc(64) -> 176 cycles kfree -> 102 cycles
10000 times kmalloc(128) -> 178 cycles kfree -> 100 cycles
10000 times kmalloc(256) -> 205 cycles kfree -> 109 cycles
10000 times kmalloc(512) -> 262 cycles kfree -> 136 cycles
10000 times kmalloc(1024) -> 342 cycles kfree -> 157 cycles
10000 times kmalloc(2048) -> 701 cycles kfree -> 238 cycles
10000 times kmalloc(4096) -> 803 cycles kfree -> 364 cycles
10000 times kmalloc(8192) -> 835 cycles kfree -> 404 cycles
10000 times kmalloc(16384) -> 896 cycles kfree -> 441 cycles
2. Kmalloc: alloc/free test
10000 times kmalloc(8)/kfree -> 121 cycles
10000 times kmalloc(16)/kfree -> 121 cycles
10000 times kmalloc(32)/kfree -> 123 cycles
10000 times kmalloc(64)/kfree -> 142 cycles
10000 times kmalloc(128)/kfree -> 121 cycles
10000 times kmalloc(256)/kfree -> 119 cycles
10000 times kmalloc(512)/kfree -> 119 cycles
10000 times kmalloc(1024)/kfree -> 119 cycles
10000 times kmalloc(2048)/kfree -> 119 cycles
10000 times kmalloc(4096)/kfree -> 119 cycles
10000 times kmalloc(8192)/kfree -> 119 cycles
10000 times kmalloc(16384)/kfree -> 119 cycles
[akpm@linux-foundation.org: propagate gfp_t into cache_random_seq_create()]
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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kmem_cache_shrink()
When we call __kmem_cache_shrink on memory cgroup removal, we need to
synchronize kmem_cache->cpu_partial update with put_cpu_partial that
might be running on other cpus. Currently, we achieve that by using
kick_all_cpus_sync, which works as a system wide memory barrier. Though
fast it is, this method has a flaw - it issues a lot of IPIs, which
might hurt high performance or real-time workloads.
To fix this, let's replace kick_all_cpus_sync with synchronize_sched.
Although the latter one may take much longer to finish, it shouldn't be
a problem in this particular case, because memory cgroups are destroyed
asynchronously from a workqueue so that no user visible effects should
be introduced. OTOH, it will save us from excessive IPIs when someone
removes a cgroup.
Anyway, even if using synchronize_sched turns out to take too long, we
can always introduce a kind of __kmem_cache_shrink batching so that this
method would only be called once per one cgroup destruction (not per
each per memcg kmem cache as it is now).
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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To check whether free objects exist or not precisely, we need to grab a
lock. But, accuracy isn't that important because race window would be
even small and if there is too much free object, cache reaper would reap
it. So, this patch makes the check for free object exisistence not to
hold a lock. This will reduce lock contention in heavily allocation
case.
Note that until now, n->shared can be freed during the processing by
writing slabinfo, but, with some trick in this patch, we can access it
freely within interrupt disabled period.
Below is the result of concurrent allocation/free in slab allocation
benchmark made by Christoph a long time ago. I make the output simpler.
The number shows cycle count during alloc/free respectively so less is
better.
* Before
Kmalloc N*alloc N*free(32): Average=248/966
Kmalloc N*alloc N*free(64): Average=261/949
Kmalloc N*alloc N*free(128): Average=314/1016
Kmalloc N*alloc N*free(256): Average=741/1061
Kmalloc N*alloc N*free(512): Average=1246/1152
Kmalloc N*alloc N*free(1024): Average=2437/1259
Kmalloc N*alloc N*free(2048): Average=4980/1800
Kmalloc N*alloc N*free(4096): Average=9000/2078
* After
Kmalloc N*alloc N*free(32): Average=344/792
Kmalloc N*alloc N*free(64): Average=347/882
Kmalloc N*alloc N*free(128): Average=390/959
Kmalloc N*alloc N*free(256): Average=393/1067
Kmalloc N*alloc N*free(512): Average=683/1229
Kmalloc N*alloc N*free(1024): Average=1295/1325
Kmalloc N*alloc N*free(2048): Average=2513/1664
Kmalloc N*alloc N*free(4096): Average=4742/2172
It shows that allocation performance decreases for the object size up to
128 and it may be due to extra checks in cache_alloc_refill(). But,
with considering improvement of free performance, net result looks the
same. Result for other size class looks very promising, roughly, 50%
performance improvement.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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