Re: [PATCH v2] powerpc/mm: Fix growth direction for hugepages mmaps with slice
From: Christophe LEROY <hidden>
Date: 2018-01-22 08:22:20
Possibly related (same subject, not in this thread)
- 2018-01-17 · Re: [PATCH v2] powerpc/mm: Fix growth direction for hugepages mmaps with slice · Christophe LEROY <hidden>
- 2018-01-17 · Re: [PATCH v2] powerpc/mm: Fix growth direction for hugepages mmaps with slice · Aneesh Kumar K.V <hidden>
- 2018-01-16 · Re: [PATCH v2] powerpc/mm: Fix growth direction for hugepages mmaps with slice · Christophe LEROY <hidden>
- 2018-01-16 · Re: [PATCH v2] powerpc/mm: Fix growth direction for hugepages mmaps with slice · Aneesh Kumar K.V <hidden>
- 2018-01-09 · [PATCH v2] powerpc/mm: Fix growth direction for hugepages mmaps with slice · Christophe Leroy <hidden>
Le 19/01/2018 à 11:05, Aneesh Kumar K.V a écrit :
Did a reply instead of reply-all. Aneesh Kumar K.V [off-list ref] writes:quoted
Christophe LEROY [off-list ref] writes:quoted
Le 17/01/2018 à 04:19, Aneesh Kumar K.V a écrit :quoted
On 01/16/2018 10:18 PM, Christophe LEROY wrote:quoted
Le 16/01/2018 à 17:03, Aneesh Kumar K.V a écrit :quoted
Christophe Leroy [off-list ref] writes:quoted
An application running with libhugetlbfs fails to allocate additional pages to HEAP due to the hugemap being done inconditionally as topdown mapping: mmap(0x10080000, 1572864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0) = 0x73e80000 [...] mmap(0x74000000, 1048576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0x180000) = 0x73d80000 munmap(0x73d80000, 1048576) = 0 [...] mmap(0x74000000, 1572864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0x180000) = 0x73d00000 munmap(0x73d00000, 1572864) = 0 [...] mmap(0x74000000, 1572864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0x180000) = 0x73d00000 munmap(0x73d00000, 1572864) = 0 [...]Can you explain the failure details above. I am not sure I understand what to read from the above output.libhugetlbfs first requests an area of size 1.5Mbytes, at address 0x10080000 mmap() returns an area at address 0x73e80000 Then libhugetlbfs requests an additional area on top of that, ie at address 0x74000000, to expand the heap. But mmap() returns an area at address 0x73d80000, ie under the previous area.Can you share the test details?. Why does it not fail on book3s64? We use topdown search with book3s64.I don't know about book3s64, I only have 8xx. Here is my test app:The test ran fine on ppc64. kvaneesh@ltctulc6a-p1:[~]$ HUGETLB_MORECORE=yes ./a.out 10000000-10010000 r-xp 00000000 fc:00 9044312 /home/kvaneesh/a.out 10010000-10020000 r--p 00000000 fc:00 9044312 /home/kvaneesh/a.out 10020000-10030000 rw-p 00010000 fc:00 9044312 /home/kvaneesh/a.out 7ffff7d60000-7ffff7f10000 r-xp 00000000 fc:00 9250090 /lib/powerpc64le-linux-gnu/libc-2.23.so 7ffff7f10000-7ffff7f20000 r--p 001a0000 fc:00 9250090 /lib/powerpc64le-linux-gnu/libc-2.23.so 7ffff7f20000-7ffff7f30000 rw-p 001b0000 fc:00 9250090 /lib/powerpc64le-linux-gnu/libc-2.23.so 7ffff7f40000-7ffff7f60000 r-xp 00000000 fc:00 10754812 /usr/lib/libhugetlbfs.so.0 7ffff7f60000-7ffff7f70000 r--p 00010000 fc:00 10754812 /usr/lib/libhugetlbfs.so.0 7ffff7f70000-7ffff7f80000 rw-p 00020000 fc:00 10754812 /usr/lib/libhugetlbfs.so.0 7ffff7f80000-7ffff7fa0000 r-xp 00000000 00:00 0 [vdso] 7ffff7fa0000-7ffff7fe0000 r-xp 00000000 fc:00 9250107 /lib/powerpc64le-linux-gnu/ld-2.23.so 7ffff7fe0000-7ffff7ff0000 r--p 00030000 fc:00 9250107 /lib/powerpc64le-linux-gnu/ld-2.23.so 7ffff7ff0000-7ffff8000000 rw-p 00040000 fc:00 9250107 /lib/powerpc64le-linux-gnu/ld-2.23.so 7ffffffd0000-800000000000 rw-p 00000000 00:00 0 [stack] Allocated 1Mbytes at 0x10000000010 Allocated 1Mbytes at 0x10002000020 Allocated 1Mbytes at 0x10004000030 10000000-10010000 r-xp 00000000 fc:00 9044312 /home/kvaneesh/a.out 10010000-10020000 r--p 00000000 fc:00 9044312 /home/kvaneesh/a.out 10020000-10030000 rw-p 00010000 fc:00 9044312 /home/kvaneesh/a.out 10000000000-10003000000 rw-p 00000000 00:0d 1041435 /anon_hugepage (deleted) 10003000000-10005000000 rw-p 03000000 00:0d 1041436 /anon_hugepage (deleted) 10005000000-10007000000 rw-p 05000000 00:0d 1041437 /anon_hugepage (deleted) 7ffff7d60000-7ffff7f10000 r-xp 00000000 fc:00 9250090 /lib/powerpc64le-linux-gnu/libc-2.23.so 7ffff7f10000-7ffff7f20000 r--p 001a0000 fc:00 9250090 /lib/powerpc64le-linux-gnu/libc-2.23.so 7ffff7f20000-7ffff7f30000 rw-p 001b0000 fc:00 9250090 /lib/powerpc64le-linux-gnu/libc-2.23.so 7ffff7f40000-7ffff7f60000 r-xp 00000000 fc:00 10754812 /usr/lib/libhugetlbfs.so.0 7ffff7f60000-7ffff7f70000 r--p 00010000 fc:00 10754812 /usr/lib/libhugetlbfs.so.0 7ffff7f70000-7ffff7f80000 rw-p 00020000 fc:00 10754812 /usr/lib/libhugetlbfs.so.0 7ffff7f80000-7ffff7fa0000 r-xp 00000000 00:00 0 [vdso] 7ffff7fa0000-7ffff7fe0000 r-xp 00000000 fc:00 9250107 /lib/powerpc64le-linux-gnu/ld-2.23.so 7ffff7fe0000-7ffff7ff0000 r--p 00030000 fc:00 9250107 /lib/powerpc64le-linux-gnu/ld-2.23.so 7ffff7ff0000-7ffff8000000 rw-p 00040000 fc:00 9250107 /lib/powerpc64le-linux-gnu/ld-2.23.so 7ffffffd0000-800000000000 rw-p 00000000 00:00 0 [stack] So i am definitely missing something. I understand that generic hugetlb get unmapped area always search bottom up and 8xx used to depend on that callback. But on ppc64 slice based get unmapped area always did topdown and I am not sure whether we should change that. More over I don't think MAP_GROWSDOWN is the right flag for selecting topdown/bottom up search. Is it that libhugetlbfs does something specific for 32 bit? Other option is to add huget_get_unmapped_area for 8xx that does bottom up search?
I think I identified the difference. In my run you have the following warning: libhugetlbfs: WARNING: Heap originates at 0x73e80000 instead of 0x10080000 In your run, there is no such warning. I tried running the test with HUGETLB_MORECORE_HEAPBASE=0x30000000, and it works without the patch: root@vgoip:~# HUGETLB_MORECORE=yes HUGETLB_MORECORE_HEAPBASE=0x30000000 ./huge_m alloc_test 00100000-00108000 r-xp 00000000 00:00 0 [vdso] 0fde4000-0fde8000 r-xp 00000000 00:0f 168 /lib/libdl-2.23.so 0fde8000-0fe00000 ---p 00004000 00:0f 168 /lib/libdl-2.23.so 0fe00000-0fe04000 r--p 0000c000 00:0f 168 /lib/libdl-2.23.so 0fe04000-0fe08000 rwxp 00010000 00:0f 168 /lib/libdl-2.23.so 0fe18000-0ff88000 r-xp 00000000 00:0f 191 /lib/libc-2.23.so 0ff88000-0ffa4000 ---p 00170000 00:0f 191 /lib/libc-2.23.so 0ffa4000-0ffa8000 r--p 0017c000 00:0f 191 /lib/libc-2.23.so 0ffa8000-0ffac000 rwxp 00180000 00:0f 191 /lib/libc-2.23.so 0ffac000-0ffb0000 rwxp 00000000 00:00 0 0ffc0000-0ffd4000 r-xp 00000000 00:0f 90 /lib/libhugetlbfs.so 0ffd4000-0ffe0000 ---p 00014000 00:0f 90 /lib/libhugetlbfs.so 0ffe0000-0ffe4000 rwxp 00010000 00:0f 90 /lib/libhugetlbfs.so 0ffe4000-0fff0000 rwxp 00000000 00:00 0 10000000-10004000 r-xp 00000000 00:0f 3076 /root/huge_malloc_test 10010000-10014000 rwxp 00000000 00:0f 3076 /root/huge_malloc_test 77ee0000-77f04000 r-xp 00000000 00:0f 171 /lib/ld-2.23.so 77f1c000-77f20000 r--p 0002c000 00:0f 171 /lib/ld-2.23.so 77f20000-77f24000 rwxp 00030000 00:0f 171 /lib/ld-2.23.so 7f830000-7f854000 rw-p 00000000 00:00 0 [stack] Allocated 1Mbytes at 0x30000008 Allocated 1Mbytes at 0x30100010 Allocated 1Mbytes at 0x30200018 00100000-00108000 r-xp 00000000 00:00 0 [vdso] 0fde4000-0fde8000 r-xp 00000000 00:0f 168 /lib/libdl-2.23.so 0fde8000-0fe00000 ---p 00004000 00:0f 168 /lib/libdl-2.23.so 0fe00000-0fe04000 r--p 0000c000 00:0f 168 /lib/libdl-2.23.so 0fe04000-0fe08000 rwxp 00010000 00:0f 168 /lib/libdl-2.23.so 0fe18000-0ff88000 r-xp 00000000 00:0f 191 /lib/libc-2.23.so 0ff88000-0ffa4000 ---p 00170000 00:0f 191 /lib/libc-2.23.so 0ffa4000-0ffa8000 r--p 0017c000 00:0f 191 /lib/libc-2.23.so 0ffa8000-0ffac000 rwxp 00180000 00:0f 191 /lib/libc-2.23.so 0ffac000-0ffb0000 rwxp 00000000 00:00 0 0ffc0000-0ffd4000 r-xp 00000000 00:0f 90 /lib/libhugetlbfs.so 0ffd4000-0ffe0000 ---p 00014000 00:0f 90 /lib/libhugetlbfs.so 0ffe0000-0ffe4000 rwxp 00010000 00:0f 90 /lib/libhugetlbfs.so 0ffe4000-0fff0000 rwxp 00000000 00:00 0 10000000-10004000 r-xp 00000000 00:0f 3076 /root/huge_malloc_test 10010000-10014000 rwxp 00000000 00:0f 3076 /root/huge_malloc_test 30000000-30180000 rw-p 00000000 00:0b 7682 /anon_hugepage (deleted) 30180000-30280000 rw-p 00180000 00:0b 7683 /anon_hugepage (deleted) 30280000-30380000 rw-p 00280000 00:0b 7684 /anon_hugepage (deleted) 77ee0000-77f04000 r-xp 00000000 00:0f 171 /lib/ld-2.23.so 77f1c000-77f20000 r--p 0002c000 00:0f 171 /lib/ld-2.23.so 77f20000-77f24000 rwxp 00030000 00:0f 171 /lib/ld-2.23.so 7f830000-7f854000 rw-p 00000000 00:00 0 [stack] On your side, could you try and see with HUGETLB_MORECORE_HEAPBASE=0x11000000 ? Christophe
quoted
If you are on ppc64 irc on freenode we can discuss this there. -aneesh