| Message ID | 1662264857-11347-1-git-send-email-zhanglikernel@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [V3] Make btrfs_prepare_device parallel during mkfs.btrfs | expand |
On 2022/9/4 12:14, Li Zhang wrote: > [enhancement] > When a disk is formatted as btrfs, it calls > btrfs_prepare_device for each device, which takes too much time. > > [implementation] > Put each btrfs_prepare_device into a thread, > wait for the first thread to complete to mkfs.btrfs, > and wait for other threads to complete before adding > other devices to the file system. > > [test] > Using the btrfs-progs test case mkfs-tests, mkfs.btrfs works fine. > > Use tcmu-runner emulation to simulate two devices for testing. > Each device is 2000G (about 19.53 TiB), the region size is 4MB, > Use the following parameters for targetcli > create name=zbc0 size=20000G cfgstring=model-HM/zsize-4/conv-100@~/zbc0.raw > > Call difftime to calculate the running time of the function btrfs_prepare_device. > Calculate the time from thread creation to completion of all threads after > patching (time calculation is not included in patch submission) > The test results are as follows. > > $ lsscsi -p > [10:0:1:0] (0x14) LIO-ORG TCMU ZBC device 0002 /dev/sdb - none > [11:0:1:0] (0x14) LIO-ORG TCMU ZBC device 0002 /dev/sdc - none > > $ sudo mkfs.btrfs -d single -m single -O zoned /dev/sdc /dev/sdb -f > .... > time for prepare devices:4.000000. > .... > > $ sudo mkfs.btrfs -d single -m single -O zoned /dev/sdc /dev/sdb -f > ... > time for prepare devices:2.000000. > ... > Signed-off-by: Li Zhang <zhanglikernel@gmail.com> > --- > Issue: 496 > > V1: > * Put btrfs_prepare_device into threads and make them parallel > > V2: > * Set the 4 variables used by btrfs_prepare_device as global variables. > * Use pthread_mutex to ensure error messages are not messed up. > * Correct the error message > * Wait for all threads to exit in a loop > > V3: > * Add prefix opt to the global variables > * Format code > * Add error handler for open > > mkfs/main.c | 157 ++++++++++++++++++++++++++++++++++++++++++------------------ > 1 file changed, 110 insertions(+), 47 deletions(-) > > diff --git a/mkfs/main.c b/mkfs/main.c > index ce096d3..2c681f2 100644 > --- a/mkfs/main.c > +++ b/mkfs/main.c > @@ -31,6 +31,7 @@ > #include <uuid/uuid.h> > #include <ctype.h> > #include <blkid/blkid.h> > +#include <pthread.h> > #include "kernel-shared/ctree.h" > #include "kernel-shared/disk-io.h" > #include "kernel-shared/free-space-tree.h" > @@ -60,6 +61,20 @@ struct mkfs_allocation { > u64 system; > }; > > +static bool opt_zero_end; > +static bool opt_discard; > +static bool opt_zoned; > +static int opt_oflags; These global options can have default values. [...] > @@ -984,7 +1024,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > u32 nodesize = 0; > u32 sectorsize = 0; > u32 stripesize = 4096; > - bool zero_end = true; > + opt_zero_end = true; I'm mentioning this because if you mix code and declaration here, IIRC compiler would give you some warning. That's why you'd better just initialize the global options, other than giving them default value here. With that fixed, looks good to me. Reviewed-by: Qu Wenruo <wqu@suse.com> Thanks, Qu > int fd = -1; > int ret = 0; > int close_ret; > @@ -993,11 +1033,10 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > bool nodesize_forced = false; > bool data_profile_opt = false; > bool metadata_profile_opt = false; > - bool discard = true; > + opt_discard = true; > bool ssd = false; > - bool zoned = false; > + opt_zoned = false; > bool force_overwrite = false; > - int oflags; > char *source_dir = NULL; > bool source_dir_set = false; > bool shrink_rootdir = false; > @@ -1006,6 +1045,8 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > u64 shrink_size; > int dev_cnt = 0; > int saved_optind; > + pthread_t *t_prepare = NULL; > + struct prepare_device_progress *prepare_ctx = NULL; > char fs_uuid[BTRFS_UUID_UNPARSED_SIZE] = { 0 }; > u64 features = BTRFS_MKFS_DEFAULT_FEATURES; > u64 runtime_features = BTRFS_MKFS_DEFAULT_RUNTIME_FEATURES; > @@ -1126,7 +1167,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > break; > case 'b': > block_count = parse_size_from_string(optarg); > - zero_end = false; > + opt_zero_end = false; > break; > case 'v': > bconf_be_verbose(); > @@ -1144,7 +1185,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > BTRFS_UUID_UNPARSED_SIZE - 1); > break; > case 'K': > - discard = false; > + opt_discard = false; > break; > case 'q': > bconf_be_quiet(); > @@ -1183,7 +1224,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > if (dev_cnt == 0) > print_usage(1); > > - zoned = !!(features & BTRFS_FEATURE_INCOMPAT_ZONED); > + opt_zoned = !!(features & BTRFS_FEATURE_INCOMPAT_ZONED); > > if (source_dir_set && dev_cnt > 1) { > error("the option -r is limited to a single device"); > @@ -1225,7 +1266,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > > file = argv[optind++]; > ssd = is_ssd(file); > - if (zoned) { > + if (opt_zoned) { > if (!zone_size(file)) { > error("zoned: %s: zone size undefined", file); > exit(1); > @@ -1235,7 +1276,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > printf( > "Zoned: %s: host-managed device detected, setting zoned feature\n", > file); > - zoned = true; > + opt_zoned = true; > features |= BTRFS_FEATURE_INCOMPAT_ZONED; > } > > @@ -1302,7 +1343,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > } > } > > - if (zoned) { > + if (opt_zoned) { > if (source_dir_set) { > error("the option -r and zoned mode are incompatible"); > exit(1); > @@ -1392,7 +1433,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > * 1 zone for a metadata block group > * 1 zone for a data block group > */ > - if (zoned && block_count && block_count < 5 * zone_size(file)) { > + if (opt_zoned && block_count && block_count < 5 * zone_size(file)) { > error("size %llu is too small to make a usable filesystem", > block_count); > error("minimum size for a zoned btrfs filesystem is %llu", > @@ -1422,35 +1463,58 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > if (ret) > goto error; > > - if (zoned && (!zoned_profile_supported(BTRFS_BLOCK_GROUP_METADATA | metadata_profile) || > + if (opt_zoned && (!zoned_profile_supported(BTRFS_BLOCK_GROUP_METADATA | metadata_profile) || > !zoned_profile_supported(BTRFS_BLOCK_GROUP_DATA | data_profile))) { > error("zoned mode does not yet support RAID/DUP profiles, please specify '-d single -m single' manually"); > goto error; > } > > - dev_cnt--; > + t_prepare = calloc(dev_cnt, sizeof(*t_prepare)); > + prepare_ctx = calloc(dev_cnt, sizeof(*prepare_ctx)); > > - oflags = O_RDWR; > - if (zoned && zoned_model(file) == ZONED_HOST_MANAGED) > - oflags |= O_DIRECT; > + if (!t_prepare || !prepare_ctx) { > + error("unable to alloc thread for preparing dev"); > + goto error; > + } > > - /* > - * Open without O_EXCL so that the problem should not occur by the > - * following operation in kernel: > - * (btrfs_register_one_device() fails if O_EXCL is on) > - */ > - fd = open(file, oflags); > + pthread_mutex_init(&prepare_mutex, NULL); > + opt_oflags = O_RDWR; > + for (i = 0; i < dev_cnt; i++) { > + if (opt_zoned && zoned_model(argv[optind + i - 1]) == > + ZONED_HOST_MANAGED) { > + opt_oflags |= O_DIRECT; > + break; > + } > + } > + for (i = 0; i < dev_cnt; i++) { > + prepare_ctx[i].file = argv[optind + i - 1]; > + prepare_ctx[i].block_count = block_count; > + prepare_ctx[i].dev_block_count = block_count; > + ret = pthread_create(&t_prepare[i], NULL, > + prepare_one_dev, &prepare_ctx[i]); > + if (ret) { > + error("create thread for prepare devices: %s failed, " > + "errno: %d", > + prepare_ctx[i].file, ret); > + goto error; > + } > + } > + for (i = 0; i < dev_cnt; i++) > + pthread_join(t_prepare[i], NULL); > + ret = prepare_ctx[0].ret; > + > + if (ret) { > + error("unable prepare device: %s\n", prepare_ctx[0].file); > + goto error; > + } > + > + dev_cnt--; > + fd = open(file, opt_oflags); > if (fd < 0) { > error("unable to open %s: %m", file); > goto error; > } > - ret = btrfs_prepare_device(fd, file, &dev_block_count, block_count, > - (zero_end ? PREP_DEVICE_ZERO_END : 0) | > - (discard ? PREP_DEVICE_DISCARD : 0) | > - (bconf.verbose ? PREP_DEVICE_VERBOSE : 0) | > - (zoned ? PREP_DEVICE_ZONED : 0)); > - if (ret) > - goto error; > + dev_block_count = prepare_ctx[0].dev_block_count; > if (block_count && block_count > dev_block_count) { > error("%s is smaller than requested size, expected %llu, found %llu", > file, (unsigned long long)block_count, > @@ -1459,7 +1523,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > } > > /* To create the first block group and chunk 0 in make_btrfs */ > - system_group_size = zoned ? zone_size(file) : BTRFS_MKFS_SYSTEM_GROUP_SIZE; > + system_group_size = opt_zoned ? zone_size(file) : BTRFS_MKFS_SYSTEM_GROUP_SIZE; > if (dev_block_count < system_group_size) { > error("device is too small to make filesystem, must be at least %llu", > (unsigned long long)system_group_size); > @@ -1487,7 +1551,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > mkfs_cfg.runtime_features = runtime_features; > mkfs_cfg.csum_type = csum_type; > mkfs_cfg.leaf_data_size = __BTRFS_LEAF_DATA_SIZE(nodesize); > - if (zoned) > + if (opt_zoned) > mkfs_cfg.zone_size = zone_size(file); > else > mkfs_cfg.zone_size = 0; > @@ -1558,14 +1622,10 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > goto raid_groups; > > while (dev_cnt-- > 0) { > + int dev_index = argc - saved_optind - dev_cnt - 1; > file = argv[optind++]; > > - /* > - * open without O_EXCL so that the problem should not > - * occur by the following processing. > - * (btrfs_register_one_device() fails if O_EXCL is on) > - */ > - fd = open(file, O_RDWR); > + fd = open(file, opt_oflags); > if (fd < 0) { > error("unable to open %s: %m", file); > goto error; > @@ -1578,13 +1638,12 @@ int BOX_MAIN(mkfs)(int argc, char **argv) > close(fd); > continue; > } > - ret = btrfs_prepare_device(fd, file, &dev_block_count, > - block_count, > - (bconf.verbose ? PREP_DEVICE_VERBOSE : 0) | > - (zero_end ? PREP_DEVICE_ZERO_END : 0) | > - (discard ? PREP_DEVICE_DISCARD : 0) | > - (zoned ? PREP_DEVICE_ZONED : 0)); > - if (ret) { > + dev_block_count = prepare_ctx[dev_index] > + .dev_block_count; > + > + if (prepare_ctx[dev_index].ret) { > + error("unable prepare device: %s.\n", > + prepare_ctx[dev_index].file); > goto error; > } > > @@ -1714,8 +1773,8 @@ raid_groups: > btrfs_group_profile_str(metadata_profile), > pretty_size(allocation.system)); > printf("SSD detected: %s\n", ssd ? "yes" : "no"); > - printf("Zoned device: %s\n", zoned ? "yes" : "no"); > - if (zoned) > + printf("Zoned device: %s\n", opt_zoned ? "yes" : "no"); > + if (opt_zoned) > printf(" Zone size: %s\n", > pretty_size(fs_info->zone_size)); > btrfs_parse_fs_features_to_string(features_buf, features); > @@ -1763,12 +1822,16 @@ out: > > btrfs_close_all_devices(); > free(label); > - > + free(t_prepare); > + free(prepare_ctx); > return !!ret; > + > error: > if (fd > 0) > close(fd); > > + free(t_prepare); > + free(prepare_ctx); > free(label); > exit(1); > success:
diff --git a/mkfs/main.c b/mkfs/main.c index ce096d3..2c681f2 100644 --- a/mkfs/main.c +++ b/mkfs/main.c @@ -31,6 +31,7 @@ #include <uuid/uuid.h> #include <ctype.h> #include <blkid/blkid.h> +#include <pthread.h> #include "kernel-shared/ctree.h" #include "kernel-shared/disk-io.h" #include "kernel-shared/free-space-tree.h" @@ -60,6 +61,20 @@ struct mkfs_allocation { u64 system; }; +static bool opt_zero_end; +static bool opt_discard; +static bool opt_zoned; +static int opt_oflags; + +static pthread_mutex_t prepare_mutex; + +struct prepare_device_progress { + char *file; + u64 dev_block_count; + u64 block_count; + int ret; +}; + static int create_metadata_block_groups(struct btrfs_root *root, bool mixed, struct mkfs_allocation *allocation) { @@ -969,6 +984,31 @@ fail: return ret; } +static void *prepare_one_dev(void *ctx) +{ + struct prepare_device_progress *prepare_ctx = ctx; + int fd; + + fd = open(prepare_ctx->file, opt_oflags); + if (fd < 0) { + pthread_mutex_lock(&prepare_mutex); + error("unable to open %s: %m", prepare_ctx->file); + pthread_mutex_unlock(&prepare_mutex); + prepare_ctx->ret = fd; + return NULL; + } + prepare_ctx->ret = btrfs_prepare_device(fd, + prepare_ctx->file, + &prepare_ctx->dev_block_count, + prepare_ctx->block_count, + (bconf.verbose ? PREP_DEVICE_VERBOSE : 0) | + (opt_zero_end ? PREP_DEVICE_ZERO_END : 0) | + (opt_discard ? PREP_DEVICE_DISCARD : 0) | + (opt_zoned ? PREP_DEVICE_ZONED : 0)); + close(fd); + return NULL; +} + int BOX_MAIN(mkfs)(int argc, char **argv) { char *file; @@ -984,7 +1024,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) u32 nodesize = 0; u32 sectorsize = 0; u32 stripesize = 4096; - bool zero_end = true; + opt_zero_end = true; int fd = -1; int ret = 0; int close_ret; @@ -993,11 +1033,10 @@ int BOX_MAIN(mkfs)(int argc, char **argv) bool nodesize_forced = false; bool data_profile_opt = false; bool metadata_profile_opt = false; - bool discard = true; + opt_discard = true; bool ssd = false; - bool zoned = false; + opt_zoned = false; bool force_overwrite = false; - int oflags; char *source_dir = NULL; bool source_dir_set = false; bool shrink_rootdir = false; @@ -1006,6 +1045,8 @@ int BOX_MAIN(mkfs)(int argc, char **argv) u64 shrink_size; int dev_cnt = 0; int saved_optind; + pthread_t *t_prepare = NULL; + struct prepare_device_progress *prepare_ctx = NULL; char fs_uuid[BTRFS_UUID_UNPARSED_SIZE] = { 0 }; u64 features = BTRFS_MKFS_DEFAULT_FEATURES; u64 runtime_features = BTRFS_MKFS_DEFAULT_RUNTIME_FEATURES; @@ -1126,7 +1167,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) break; case 'b': block_count = parse_size_from_string(optarg); - zero_end = false; + opt_zero_end = false; break; case 'v': bconf_be_verbose(); @@ -1144,7 +1185,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) BTRFS_UUID_UNPARSED_SIZE - 1); break; case 'K': - discard = false; + opt_discard = false; break; case 'q': bconf_be_quiet(); @@ -1183,7 +1224,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) if (dev_cnt == 0) print_usage(1); - zoned = !!(features & BTRFS_FEATURE_INCOMPAT_ZONED); + opt_zoned = !!(features & BTRFS_FEATURE_INCOMPAT_ZONED); if (source_dir_set && dev_cnt > 1) { error("the option -r is limited to a single device"); @@ -1225,7 +1266,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) file = argv[optind++]; ssd = is_ssd(file); - if (zoned) { + if (opt_zoned) { if (!zone_size(file)) { error("zoned: %s: zone size undefined", file); exit(1); @@ -1235,7 +1276,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) printf( "Zoned: %s: host-managed device detected, setting zoned feature\n", file); - zoned = true; + opt_zoned = true; features |= BTRFS_FEATURE_INCOMPAT_ZONED; } @@ -1302,7 +1343,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) } } - if (zoned) { + if (opt_zoned) { if (source_dir_set) { error("the option -r and zoned mode are incompatible"); exit(1); @@ -1392,7 +1433,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) * 1 zone for a metadata block group * 1 zone for a data block group */ - if (zoned && block_count && block_count < 5 * zone_size(file)) { + if (opt_zoned && block_count && block_count < 5 * zone_size(file)) { error("size %llu is too small to make a usable filesystem", block_count); error("minimum size for a zoned btrfs filesystem is %llu", @@ -1422,35 +1463,58 @@ int BOX_MAIN(mkfs)(int argc, char **argv) if (ret) goto error; - if (zoned && (!zoned_profile_supported(BTRFS_BLOCK_GROUP_METADATA | metadata_profile) || + if (opt_zoned && (!zoned_profile_supported(BTRFS_BLOCK_GROUP_METADATA | metadata_profile) || !zoned_profile_supported(BTRFS_BLOCK_GROUP_DATA | data_profile))) { error("zoned mode does not yet support RAID/DUP profiles, please specify '-d single -m single' manually"); goto error; } - dev_cnt--; + t_prepare = calloc(dev_cnt, sizeof(*t_prepare)); + prepare_ctx = calloc(dev_cnt, sizeof(*prepare_ctx)); - oflags = O_RDWR; - if (zoned && zoned_model(file) == ZONED_HOST_MANAGED) - oflags |= O_DIRECT; + if (!t_prepare || !prepare_ctx) { + error("unable to alloc thread for preparing dev"); + goto error; + } - /* - * Open without O_EXCL so that the problem should not occur by the - * following operation in kernel: - * (btrfs_register_one_device() fails if O_EXCL is on) - */ - fd = open(file, oflags); + pthread_mutex_init(&prepare_mutex, NULL); + opt_oflags = O_RDWR; + for (i = 0; i < dev_cnt; i++) { + if (opt_zoned && zoned_model(argv[optind + i - 1]) == + ZONED_HOST_MANAGED) { + opt_oflags |= O_DIRECT; + break; + } + } + for (i = 0; i < dev_cnt; i++) { + prepare_ctx[i].file = argv[optind + i - 1]; + prepare_ctx[i].block_count = block_count; + prepare_ctx[i].dev_block_count = block_count; + ret = pthread_create(&t_prepare[i], NULL, + prepare_one_dev, &prepare_ctx[i]); + if (ret) { + error("create thread for prepare devices: %s failed, " + "errno: %d", + prepare_ctx[i].file, ret); + goto error; + } + } + for (i = 0; i < dev_cnt; i++) + pthread_join(t_prepare[i], NULL); + ret = prepare_ctx[0].ret; + + if (ret) { + error("unable prepare device: %s\n", prepare_ctx[0].file); + goto error; + } + + dev_cnt--; + fd = open(file, opt_oflags); if (fd < 0) { error("unable to open %s: %m", file); goto error; } - ret = btrfs_prepare_device(fd, file, &dev_block_count, block_count, - (zero_end ? PREP_DEVICE_ZERO_END : 0) | - (discard ? PREP_DEVICE_DISCARD : 0) | - (bconf.verbose ? PREP_DEVICE_VERBOSE : 0) | - (zoned ? PREP_DEVICE_ZONED : 0)); - if (ret) - goto error; + dev_block_count = prepare_ctx[0].dev_block_count; if (block_count && block_count > dev_block_count) { error("%s is smaller than requested size, expected %llu, found %llu", file, (unsigned long long)block_count, @@ -1459,7 +1523,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) } /* To create the first block group and chunk 0 in make_btrfs */ - system_group_size = zoned ? zone_size(file) : BTRFS_MKFS_SYSTEM_GROUP_SIZE; + system_group_size = opt_zoned ? zone_size(file) : BTRFS_MKFS_SYSTEM_GROUP_SIZE; if (dev_block_count < system_group_size) { error("device is too small to make filesystem, must be at least %llu", (unsigned long long)system_group_size); @@ -1487,7 +1551,7 @@ int BOX_MAIN(mkfs)(int argc, char **argv) mkfs_cfg.runtime_features = runtime_features; mkfs_cfg.csum_type = csum_type; mkfs_cfg.leaf_data_size = __BTRFS_LEAF_DATA_SIZE(nodesize); - if (zoned) + if (opt_zoned) mkfs_cfg.zone_size = zone_size(file); else mkfs_cfg.zone_size = 0; @@ -1558,14 +1622,10 @@ int BOX_MAIN(mkfs)(int argc, char **argv) goto raid_groups; while (dev_cnt-- > 0) { + int dev_index = argc - saved_optind - dev_cnt - 1; file = argv[optind++]; - /* - * open without O_EXCL so that the problem should not - * occur by the following processing. - * (btrfs_register_one_device() fails if O_EXCL is on) - */ - fd = open(file, O_RDWR); + fd = open(file, opt_oflags); if (fd < 0) { error("unable to open %s: %m", file); goto error; @@ -1578,13 +1638,12 @@ int BOX_MAIN(mkfs)(int argc, char **argv) close(fd); continue; } - ret = btrfs_prepare_device(fd, file, &dev_block_count, - block_count, - (bconf.verbose ? PREP_DEVICE_VERBOSE : 0) | - (zero_end ? PREP_DEVICE_ZERO_END : 0) | - (discard ? PREP_DEVICE_DISCARD : 0) | - (zoned ? PREP_DEVICE_ZONED : 0)); - if (ret) { + dev_block_count = prepare_ctx[dev_index] + .dev_block_count; + + if (prepare_ctx[dev_index].ret) { + error("unable prepare device: %s.\n", + prepare_ctx[dev_index].file); goto error; } @@ -1714,8 +1773,8 @@ raid_groups: btrfs_group_profile_str(metadata_profile), pretty_size(allocation.system)); printf("SSD detected: %s\n", ssd ? "yes" : "no"); - printf("Zoned device: %s\n", zoned ? "yes" : "no"); - if (zoned) + printf("Zoned device: %s\n", opt_zoned ? "yes" : "no"); + if (opt_zoned) printf(" Zone size: %s\n", pretty_size(fs_info->zone_size)); btrfs_parse_fs_features_to_string(features_buf, features); @@ -1763,12 +1822,16 @@ out: btrfs_close_all_devices(); free(label); - + free(t_prepare); + free(prepare_ctx); return !!ret; + error: if (fd > 0) close(fd); + free(t_prepare); + free(prepare_ctx); free(label); exit(1); success:
[enhancement] When a disk is formatted as btrfs, it calls btrfs_prepare_device for each device, which takes too much time. [implementation] Put each btrfs_prepare_device into a thread, wait for the first thread to complete to mkfs.btrfs, and wait for other threads to complete before adding other devices to the file system. [test] Using the btrfs-progs test case mkfs-tests, mkfs.btrfs works fine. Use tcmu-runner emulation to simulate two devices for testing. Each device is 2000G (about 19.53 TiB), the region size is 4MB, Use the following parameters for targetcli create name=zbc0 size=20000G cfgstring=model-HM/zsize-4/conv-100@~/zbc0.raw Call difftime to calculate the running time of the function btrfs_prepare_device. Calculate the time from thread creation to completion of all threads after patching (time calculation is not included in patch submission) The test results are as follows. $ lsscsi -p [10:0:1:0] (0x14) LIO-ORG TCMU ZBC device 0002 /dev/sdb - none [11:0:1:0] (0x14) LIO-ORG TCMU ZBC device 0002 /dev/sdc - none $ sudo mkfs.btrfs -d single -m single -O zoned /dev/sdc /dev/sdb -f .... time for prepare devices:4.000000. .... $ sudo mkfs.btrfs -d single -m single -O zoned /dev/sdc /dev/sdb -f ... time for prepare devices:2.000000. ... Signed-off-by: Li Zhang <zhanglikernel@gmail.com> --- Issue: 496 V1: * Put btrfs_prepare_device into threads and make them parallel V2: * Set the 4 variables used by btrfs_prepare_device as global variables. * Use pthread_mutex to ensure error messages are not messed up. * Correct the error message * Wait for all threads to exit in a loop V3: * Add prefix opt to the global variables * Format code * Add error handler for open mkfs/main.c | 157 ++++++++++++++++++++++++++++++++++++++++++------------------ 1 file changed, 110 insertions(+), 47 deletions(-)