| Message ID | 1630665170.14504134.1407251982055.JavaMail.zimbra@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 2014-08-05 at 11:19 -0400, David Jeffery wrote: > If a SIGKILL is sent to a task waiting in __nfs_iocounter_wait, > it will busy-wait or soft lockup in its while loop. > nfs_wait_bit_killable won't sleep, and the loop won't exit on > the error return. > > Stop the busy-wait by breaking out of the loop when > nfs_wait_bit_killable returns an error. > > Signed-off-by: David Jeffery <djeffery@redhat.com> > --- > I'm not completely confident this is the right solution. I > would like feedback if the intention was to break out of > this loop on error, or if we do need to wait here until > io_count hits zero and use something other than > nfs_wait_bit_killable to wait in case of SIGKILL. > > pagelist.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c > index 17fab89..f29a690 100644 > --- a/fs/nfs/pagelist.c > +++ b/fs/nfs/pagelist.c > @@ -116,7 +116,7 @@ __nfs_iocounter_wait(struct nfs_io_counter *c) > if (atomic_read(&c->io_count) == 0) > break; > ret = nfs_wait_bit_killable(&c->flags); > - } while (atomic_read(&c->io_count) != 0); > + } while (atomic_read(&c->io_count) != 0 && !ret); > finish_wait(wq, &q.wait); > return ret; > } Applied.
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index 17fab89..f29a690 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -116,7 +116,7 @@ __nfs_iocounter_wait(struct nfs_io_counter *c) if (atomic_read(&c->io_count) == 0) break; ret = nfs_wait_bit_killable(&c->flags); - } while (atomic_read(&c->io_count) != 0); + } while (atomic_read(&c->io_count) != 0 && !ret); finish_wait(wq, &q.wait); return ret; }
If a SIGKILL is sent to a task waiting in __nfs_iocounter_wait, it will busy-wait or soft lockup in its while loop. nfs_wait_bit_killable won't sleep, and the loop won't exit on the error return. Stop the busy-wait by breaking out of the loop when nfs_wait_bit_killable returns an error. Signed-off-by: David Jeffery <djeffery@redhat.com> --- I'm not completely confident this is the right solution. I would like feedback if the intention was to break out of this loop on error, or if we do need to wait here until io_count hits zero and use something other than nfs_wait_bit_killable to wait in case of SIGKILL. pagelist.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html