| Message ID | 1cb14fe54e546b530d0f3991062ff8bca5cc3394.1441805445.git.zhaolei@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Sep 09, 2015 at 09:32:21PM +0800, Zhao Lei wrote: > Bug: > # btrfs-image -t0 -c9 /dev/sda6 /tmp/btrfs_image.img > (hang) > # btrfs-image -r -t0 /tmp/btrfs_image.img /dev/sda6 > (hang) > > Reason: > Program need to create at least 1 thread for compress/decompress. > but if user specify -t0 in argument, it overwrite the default value > of 1, then the program really created 0 thread, and caused above > error. > > Fix: > We can add a check, to make program not allow -t0 argument, > but there are still exist another problem. > for ex, in node with 4 cpus: > btrfs-image -c9 -t1: 4 threads (1 means use nr_cpus) > -c9 -t2: 2 threads > -c9 -t3: 3 threads > ... > (-t1 have more threads than -t2 and -t3) > > So we change to use value of 0 as "use nr_cpus threads", then: > btrfs-image [no -t arg]: use nr_cpus threads > -t0: use nr_cpus threads > -t val: use val threads. > > Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> All 3 patches applied, thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/btrfs-image.c b/btrfs-image.c index f48d81a..7f49cce 100644 --- a/btrfs-image.c +++ b/btrfs-image.c @@ -2690,7 +2690,7 @@ int main(int argc, char *argv[]) { char *source; char *target; - u64 num_threads = 1; + u64 num_threads = 0; u64 compress_level = 0; int create = 1; int old_restore = 0; @@ -2786,7 +2786,8 @@ int main(int argc, char *argv[]) } } - if (num_threads == 1 && compress_level > 0) { + if ((compress_level > 0 || create == 0) && + num_threads == 0) { num_threads = sysconf(_SC_NPROCESSORS_ONLN); if (num_threads <= 0) num_threads = 1;
Bug: # btrfs-image -t0 -c9 /dev/sda6 /tmp/btrfs_image.img (hang) # btrfs-image -r -t0 /tmp/btrfs_image.img /dev/sda6 (hang) Reason: Program need to create at least 1 thread for compress/decompress. but if user specify -t0 in argument, it overwrite the default value of 1, then the program really created 0 thread, and caused above error. Fix: We can add a check, to make program not allow -t0 argument, but there are still exist another problem. for ex, in node with 4 cpus: btrfs-image -c9 -t1: 4 threads (1 means use nr_cpus) -c9 -t2: 2 threads -c9 -t3: 3 threads ... (-t1 have more threads than -t2 and -t3) So we change to use value of 0 as "use nr_cpus threads", then: btrfs-image [no -t arg]: use nr_cpus threads -t0: use nr_cpus threads -t val: use val threads. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> --- btrfs-image.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)