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    "msgid": "<>",
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    "date": "2018-07-10T16:59:53",
    "name": "[v5,0/8] Add read-write concurrency to rte_hash library",
    "submitter": {
        "id": 754,
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        "name": "Wang, Yipeng1",
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            "date": "2018-07-10T16:59:53",
            "name": "Add read-write concurrency to rte_hash library",
            "version": 5,
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        "Subject": "[dpdk-dev] [PATCH v5 0/8] Add read-write concurrency to rte_hash\n\tlibrary",
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        "From": "Yipeng Wang <>",
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        "Date": "Tue, 10 Jul 2018 09:59:53 -0700",
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    "content": "This patch set adds the read-write concurrency support in rte_hash.\nA new flag value is added to indicate if read-write concurrency is needed\nduring creation time. Test cases are implemented to do functional and\nperformance tests.\n\nThe new concurrency model is based on rte_rwlock. When Intel TSX is\navailable and the users indicate to use it, the TM version of the\nrte_rwlock will be called. Both multi-writer and read-write concurrency\nare protected by the rte_rwlock instead of the x86 specific RTM\ninstructions, so the x86 specific header rte_cuckoo_hash_x86.h is removed\nand the code is infused into the main .c file.\n\nA new rte_hash_count API is proposed to count how many keys are inserted\ninto the hash table.\n\nv4->v5:\nOne typo fix in commit message that causes patch check warning.\n\nv3->v4:\n1. Change commit message titles as Pablo suggested. (Pablo)\n2. hash: remove unnecessary changes in commit 4. (Pablo)\n3. test: remove unnecessary double blank lines. (Pablo)\n4. Add Pablo's ack in commit message.\n\nv2->v3:\n1. hash: Concurrency bug fix: after beginning cuckoo path moving,\nthe last empty slot needs to be verified again in case other writers\nraced into this slot and occupy it. A new commit is added to do this\nbug fix since it applies to master head as well.\n2. hash: Concurrency bug fix: if cuckoo path is detected to be invalid,\nthe current slot needs to be emptied since it is duplicated to its\ntarget bucket.\n3. hash: \"const\" is used for types in multiple locations. (Pablo)\n4. hash: rte_malloc used for readwriter lock used wrong align\nargument. Similar fix applies to master head so a new commit is\ncreated. (Pablo)\n5. hash: ring size calculation fix is moved to front. (Pablo)\n6. hash: search-and-remove function is refactored to be more aligned\nwith other search function. (Pablo)\n7. test: using jhash in functional test for read-write concurrency.\nIt is because jhash with sequential keys incur more cuckoo path.\n8. Multiple coding style, typo, commit message fixes. (Pablo)\n\nv1->v2:\n1. Split each commit into two commits for easier review (Pablo).\n2. Add more comments in various places (Pablo).\n3. hash: In key insertion function, move duplicated key checking to\nearlier location and protect it using locks. Checking duplicated key\nshould happen first and data updates should be protected.\n4. hash: In lookup bulk function, put signature comparison in lock,\nsince writers could happen between signature match on two buckets.\n5. hash: Add write locks to reset function as well to protect resets.\n5. test: Fix 32-bit compilation error in read-write test (Pablo).\n6. test: Check total physical core count in read-write test. Don't\ntest with thread count that larger than physical core count.\n7. Other minor fixes such as typos (Pablo).\n\nYipeng Wang (8):\n  hash: fix multiwriter lock memory allocation\n  hash: fix a multi-writer race condition\n  hash: fix key slot size accuracy\n  hash: make duplicated code into functions\n  hash: add read and write concurrency support\n  test: add tests in hash table perf test\n  test: add test case for read write concurrency\n  hash: add new API function to query the key count\n\n lib/librte_hash/           |   1 -\n lib/librte_hash/rte_cuckoo_hash.c     | 701 +++++++++++++++++++++-------------\n lib/librte_hash/rte_cuckoo_hash.h     |  18 +-\n lib/librte_hash/rte_cuckoo_hash_x86.h | 164 --------\n lib/librte_hash/rte_hash.h            |  14 +\n lib/librte_hash/  |   8 +\n test/test/Makefile                    |   1 +\n test/test/test_hash.c                 |  12 +\n test/test/test_hash_multiwriter.c     |   8 +\n test/test/test_hash_perf.c            |  36 +-\n test/test/test_hash_readwrite.c       | 637 ++++++++++++++++++++++++++++++\n 11 files changed, 1155 insertions(+), 445 deletions(-)\n delete mode 100644 lib/librte_hash/rte_cuckoo_hash_x86.h\n create mode 100644 test/test/test_hash_readwrite.c"