| Message ID | 1459346743-17191-1-git-send-email-dsterba@suse.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Mar 30, 2016 at 04:05:43PM +0200, David Sterba wrote: > The allocation of node could fail if the memory is too fragmented for a > given node size, practically observed with 64k. It's not a critical path. Why not use vmalloc directly? Thanks, -liubo > > http://article.gmane.org/gmane.comp.file-systems.btrfs/54689 > > Reported-by: Jean-Denis Girard <jd.girard@sysnux.pf> > Signed-off-by: David Sterba <dsterba@suse.com> > --- > fs/btrfs/ctree.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c > index 77592931ab4f..ec7928a27aaa 100644 > --- a/fs/btrfs/ctree.c > +++ b/fs/btrfs/ctree.c > @@ -19,6 +19,7 @@ > #include <linux/sched.h> > #include <linux/slab.h> > #include <linux/rbtree.h> > +#include <linux/vmalloc.h> > #include "ctree.h" > #include "disk-io.h" > #include "transaction.h" > @@ -5361,10 +5362,13 @@ int btrfs_compare_trees(struct btrfs_root *left_root, > goto out; > } > > - tmp_buf = kmalloc(left_root->nodesize, GFP_KERNEL); > + tmp_buf = kmalloc(left_root->nodesize, GFP_KERNEL | __GFP_NOWARN); > if (!tmp_buf) { > - ret = -ENOMEM; > - goto out; > + tmp_buf = vmalloc(left_root->nodesize); > + if (!tmp_buf) { > + ret = -ENOMEM; > + goto out; > + } > } > > left_path->search_commit_root = 1; > @@ -5565,7 +5569,7 @@ int btrfs_compare_trees(struct btrfs_root *left_root, > out: > btrfs_free_path(left_path); > btrfs_free_path(right_path); > - kfree(tmp_buf); > + kvfree(tmp_buf); > return ret; > } > > -- > 2.7.1 > > -- > 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 -- 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
On Wed, Mar 30, 2016 at 10:10:45AM -0700, Liu Bo wrote: > On Wed, Mar 30, 2016 at 04:05:43PM +0200, David Sterba wrote: > > The allocation of node could fail if the memory is too fragmented for a > > given node size, practically observed with 64k. > > It's not a critical path. Why not use vmalloc directly? We should try to avoid vmalloc if possible. -- 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
Hi David, Le 30/03/2016 04:05, David Sterba a écrit : > The allocation of node could fail if the memory is too fragmented for a > given node size, practically observed with 64k. > > http://article.gmane.org/gmane.comp.file-systems.btrfs/54689 > > Reported-by: Jean-Denis Girard <jd.girard@sysnux.pf> > Signed-off-by: David Sterba <dsterba@suse.com> > --- > fs/btrfs/ctree.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c > index 77592931ab4f..ec7928a27aaa 100644 > --- a/fs/btrfs/ctree.c > +++ b/fs/btrfs/ctree.c > @@ -19,6 +19,7 @@ > #include <linux/sched.h> > #include <linux/slab.h> > #include <linux/rbtree.h> > +#include <linux/vmalloc.h> > #include "ctree.h" > #include "disk-io.h" > #include "transaction.h" > @@ -5361,10 +5362,13 @@ int btrfs_compare_trees(struct btrfs_root *left_root, > goto out; > } > > - tmp_buf = kmalloc(left_root->nodesize, GFP_KERNEL); > + tmp_buf = kmalloc(left_root->nodesize, GFP_KERNEL | __GFP_NOWARN); > if (!tmp_buf) { > - ret = -ENOMEM; > - goto out; > + tmp_buf = vmalloc(left_root->nodesize); > + if (!tmp_buf) { > + ret = -ENOMEM; > + goto out; > + } > } > > left_path->search_commit_root = 1; > @@ -5565,7 +5569,7 @@ int btrfs_compare_trees(struct btrfs_root *left_root, > out: > btrfs_free_path(left_path); > btrfs_free_path(right_path); > - kfree(tmp_buf); > + kvfree(tmp_buf); > return ret; > } > > I adapted / applied the patch for kernel-4.4.6, rebooted and now the backup completes without error, thanks a lot! Tested by: Jean-Denis Girard <jd.girard@sysnux.pf> Thanks,
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 77592931ab4f..ec7928a27aaa 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -19,6 +19,7 @@ #include <linux/sched.h> #include <linux/slab.h> #include <linux/rbtree.h> +#include <linux/vmalloc.h> #include "ctree.h" #include "disk-io.h" #include "transaction.h" @@ -5361,10 +5362,13 @@ int btrfs_compare_trees(struct btrfs_root *left_root, goto out; } - tmp_buf = kmalloc(left_root->nodesize, GFP_KERNEL); + tmp_buf = kmalloc(left_root->nodesize, GFP_KERNEL | __GFP_NOWARN); if (!tmp_buf) { - ret = -ENOMEM; - goto out; + tmp_buf = vmalloc(left_root->nodesize); + if (!tmp_buf) { + ret = -ENOMEM; + goto out; + } } left_path->search_commit_root = 1; @@ -5565,7 +5569,7 @@ int btrfs_compare_trees(struct btrfs_root *left_root, out: btrfs_free_path(left_path); btrfs_free_path(right_path); - kfree(tmp_buf); + kvfree(tmp_buf); return ret; }
The allocation of node could fail if the memory is too fragmented for a given node size, practically observed with 64k. http://article.gmane.org/gmane.comp.file-systems.btrfs/54689 Reported-by: Jean-Denis Girard <jd.girard@sysnux.pf> Signed-off-by: David Sterba <dsterba@suse.com> --- fs/btrfs/ctree.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)