Unified · Split
| @@ -935,6 +935,81 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo, · 934 unmodified lines | |||
| 935 | return ret; | 935 | return ret; |
| 936 | } | 936 | } |
| 937 | 937 | ||
| 938 | /* | ||
| 939 | * Use mdsthreshold hints set at each OPEN to determine if I/O should go | ||
| 940 | * to the MDS or over pNFS | ||
| 941 | * | ||
| 942 | * The nfs_inode read_io and write_io fields are cumulative counters reset | ||
| 943 | * when there are no layout segments. Note that in pnfs_update_layout iomode | ||
| 944 | * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a | ||
| 945 | * WRITE request. | ||
| 946 | * | ||
| 947 | * A return of true means use MDS I/O. | ||
| 948 | * | ||
| 949 | * From rfc 5661: | ||
| 950 | * If a file's size is smaller than the file size threshold, data accesses | ||
| 951 | * SHOULD be sent to the metadata server. If an I/O request has a length that | ||
| 952 | * is below the I/O size threshold, the I/O SHOULD be sent to the metadata | ||
| 953 | * server. If both file size and I/O size are provided, the client SHOULD | ||
| 954 | * reach or exceed both thresholds before sending its read or write | ||
| 955 | * requests to the data server. | ||
| 956 | */ | ||
| 957 | static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx, | ||
| 958 | struct inode *ino, int iomode) | ||
| 959 | { | ||
| 960 | struct nfs4_threshold *t = ctx->mdsthreshold; | ||
| 961 | struct nfs_inode *nfsi = NFS_I(ino); | ||
| 962 | loff_t fsize = i_size_read(ino); | ||
| 963 | bool size = false, size_set = false, io = false, io_set = false, ret = false; | ||
| 964 | |||
| 965 | if (t == NULL) | ||
| 966 | return ret; | ||
| 967 | |||
| 968 | dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n", | ||
| 969 | __func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz); | ||
| 970 | |||
| 971 | switch (iomode) { | ||
| 972 | case IOMODE_READ: | ||
| 973 | if (t->bm & THRESHOLD_RD) { | ||
| 974 | dprintk("%s fsize %llu\n", __func__, fsize); | ||
| 975 | size_set = true; | ||
| 976 | if (fsize < t->rd_sz) | ||
| 977 | size = true; | ||
| 978 | } | ||
| 979 | if (t->bm & THRESHOLD_RD_IO) { | ||
| 980 | dprintk("%s nfsi->read_io %llu\n", __func__, | ||
| 981 | nfsi->read_io); | ||
| 982 | io_set = true; | ||
| 983 | if (nfsi->read_io < t->rd_io_sz) | ||
| 984 | io = true; | ||
| 985 | } | ||
| 986 | break; | ||
| 987 | case IOMODE_RW: | ||
| 988 | if (t->bm & THRESHOLD_WR) { | ||
| 989 | dprintk("%s fsize %llu\n", __func__, fsize); | ||
| 990 | size_set = true; | ||
| 991 | if (fsize < t->wr_sz) | ||
| 992 | size = true; | ||
| 993 | } | ||
| 994 | if (t->bm & THRESHOLD_WR_IO) { | ||
| 995 | dprintk("%s nfsi->write_io %llu\n", __func__, | ||
| 996 | nfsi->write_io); | ||
| 997 | io_set = true; | ||
| 998 | if (nfsi->write_io < t->wr_io_sz) | ||
| 999 | io = true; | ||
| 1000 | } | ||
| 1001 | break; | ||
| 1002 | } | ||
| 1003 | if (size_set && io_set) { | ||
| 1004 | if (size && io) | ||
| 1005 | ret = true; | ||
| 1006 | } else if (size || io) | ||
| 1007 | ret = true; | ||
| 1008 | |||
| 1009 | dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret); | ||
| 1010 | return ret; | ||
| 1011 | } | ||
| 1012 | |||
| 938 | /* | 1013 | /* |
| 939 | * Layout segment is retreived from the server if not cached. | 1014 | * Layout segment is retreived from the server if not cached. |
| 940 | * The appropriate layout segment is referenced and returned to the caller. | 1015 | * The appropriate layout segment is referenced and returned to the caller. |
| @@ -962,6 +1037,10 @@ pnfs_update_layout(struct inode *ino, · 21 unmodified lines | |||
| 962 | 1037 | ||
| 963 | if (!pnfs_enabled_sb(NFS_SERVER(ino))) | 1038 | if (!pnfs_enabled_sb(NFS_SERVER(ino))) |
| 964 | return NULL; | 1039 | return NULL; |
| 1040 | |||
| 1041 | if (pnfs_within_mdsthreshold(ctx, ino, iomode)) | ||
| 1042 | return NULL; | ||
| 1043 | |||
| 965 | spin_lock(&ino->i_lock); | 1044 | spin_lock(&ino->i_lock); |
| 966 | lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags); | 1045 | lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags); |
| 967 | if (lo == NULL) { | 1046 | if (lo == NULL) { |