From: Liu Bo <bo.liu@linux.alibaba.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-nvdimm@lists.01.org, virtio-fs@redhat.com,
miklos@szeredi.hu, stefanha@redhat.com, dgilbert@redhat.com,
mst@redhat.com
Subject: Re: [PATCH 20/20] fuse,virtiofs: Add logic to free up a memory range
Date: Sat, 28 Mar 2020 06:06:06 +0800 [thread overview]
Message-ID: <20200327220606.GA119028@rsjd01523.et2sqa> (raw)
In-Reply-To: <20200327140114.GB32717@redhat.com>
On Fri, Mar 27, 2020 at 10:01:14AM -0400, Vivek Goyal wrote:
> On Thu, Mar 26, 2020 at 08:09:05AM +0800, Liu Bo wrote:
>
> [..]
> > > +/*
> > > + * Find first mapping in the tree and free it and return it. Do not add
> > > + * it back to free pool. If fault == true, this function should be called
> > > + * with fi->i_mmap_sem held.
> > > + */
> > > +static struct fuse_dax_mapping *inode_reclaim_one_dmap(struct fuse_conn *fc,
> > > + struct inode *inode,
> > > + bool fault)
> > > +{
> > > + struct fuse_inode *fi = get_fuse_inode(inode);
> > > + struct fuse_dax_mapping *dmap;
> > > + int ret;
> > > +
> > > + if (!fault)
> > > + down_write(&fi->i_mmap_sem);
> > > +
> > > + /*
> > > + * Make sure there are no references to inode pages using
> > > + * get_user_pages()
> > > + */
> > > + ret = fuse_break_dax_layouts(inode, 0, 0);
> >
> > Hi Vivek,
> >
> > This patch is enabling inline reclaim for fault path, but fault path
> > has already holds a locked exceptional entry which I believe the above
> > fuse_break_dax_layouts() needs to wait for, can you please elaborate
> > on how this can be avoided?
> >
>
> Hi Liubo,
>
> Can you please point to the exact lock you are referring to. I will
> check it out. Once we got rid of needing to take inode lock in
> reclaim path, that opended the door to do inline reclaim in fault
> path as well. But I was not aware of this exceptional entry lock.
Hi Vivek,
dax_iomap_{pte,pmd}_fault has called grab_mapping_entry to get a
locked entry, when this fault gets into inline reclaim, would
fuse_break_dax_layouts wait for the locked exceptional entry which is
locked in dax_iomap_{pte,pmd}_fault?
thanks,
liubo
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WARNING: multiple messages have this Message-ID (diff)
From: Liu Bo <bo.liu@linux.alibaba.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-nvdimm@lists.01.org, virtio-fs@redhat.com,
miklos@szeredi.hu, stefanha@redhat.com, dgilbert@redhat.com,
mst@redhat.com
Subject: Re: [PATCH 20/20] fuse,virtiofs: Add logic to free up a memory range
Date: Sat, 28 Mar 2020 06:06:06 +0800 [thread overview]
Message-ID: <20200327220606.GA119028@rsjd01523.et2sqa> (raw)
In-Reply-To: <20200327140114.GB32717@redhat.com>
On Fri, Mar 27, 2020 at 10:01:14AM -0400, Vivek Goyal wrote:
> On Thu, Mar 26, 2020 at 08:09:05AM +0800, Liu Bo wrote:
>
> [..]
> > > +/*
> > > + * Find first mapping in the tree and free it and return it. Do not add
> > > + * it back to free pool. If fault == true, this function should be called
> > > + * with fi->i_mmap_sem held.
> > > + */
> > > +static struct fuse_dax_mapping *inode_reclaim_one_dmap(struct fuse_conn *fc,
> > > + struct inode *inode,
> > > + bool fault)
> > > +{
> > > + struct fuse_inode *fi = get_fuse_inode(inode);
> > > + struct fuse_dax_mapping *dmap;
> > > + int ret;
> > > +
> > > + if (!fault)
> > > + down_write(&fi->i_mmap_sem);
> > > +
> > > + /*
> > > + * Make sure there are no references to inode pages using
> > > + * get_user_pages()
> > > + */
> > > + ret = fuse_break_dax_layouts(inode, 0, 0);
> >
> > Hi Vivek,
> >
> > This patch is enabling inline reclaim for fault path, but fault path
> > has already holds a locked exceptional entry which I believe the above
> > fuse_break_dax_layouts() needs to wait for, can you please elaborate
> > on how this can be avoided?
> >
>
> Hi Liubo,
>
> Can you please point to the exact lock you are referring to. I will
> check it out. Once we got rid of needing to take inode lock in
> reclaim path, that opended the door to do inline reclaim in fault
> path as well. But I was not aware of this exceptional entry lock.
Hi Vivek,
dax_iomap_{pte,pmd}_fault has called grab_mapping_entry to get a
locked entry, when this fault gets into inline reclaim, would
fuse_break_dax_layouts wait for the locked exceptional entry which is
locked in dax_iomap_{pte,pmd}_fault?
thanks,
liubo
WARNING: multiple messages have this Message-ID (diff)
From: Liu Bo <bo.liu@linux.alibaba.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: miklos@szeredi.hu, linux-nvdimm@lists.01.org,
linux-kernel@vger.kernel.org, virtio-fs@redhat.com,
mst@redhat.com, linux-fsdevel@vger.kernel.org
Subject: Re: [Virtio-fs] [PATCH 20/20] fuse, virtiofs: Add logic to free up a memory range
Date: Sat, 28 Mar 2020 06:06:06 +0800 [thread overview]
Message-ID: <20200327220606.GA119028@rsjd01523.et2sqa> (raw)
In-Reply-To: <20200327140114.GB32717@redhat.com>
On Fri, Mar 27, 2020 at 10:01:14AM -0400, Vivek Goyal wrote:
> On Thu, Mar 26, 2020 at 08:09:05AM +0800, Liu Bo wrote:
>
> [..]
> > > +/*
> > > + * Find first mapping in the tree and free it and return it. Do not add
> > > + * it back to free pool. If fault == true, this function should be called
> > > + * with fi->i_mmap_sem held.
> > > + */
> > > +static struct fuse_dax_mapping *inode_reclaim_one_dmap(struct fuse_conn *fc,
> > > + struct inode *inode,
> > > + bool fault)
> > > +{
> > > + struct fuse_inode *fi = get_fuse_inode(inode);
> > > + struct fuse_dax_mapping *dmap;
> > > + int ret;
> > > +
> > > + if (!fault)
> > > + down_write(&fi->i_mmap_sem);
> > > +
> > > + /*
> > > + * Make sure there are no references to inode pages using
> > > + * get_user_pages()
> > > + */
> > > + ret = fuse_break_dax_layouts(inode, 0, 0);
> >
> > Hi Vivek,
> >
> > This patch is enabling inline reclaim for fault path, but fault path
> > has already holds a locked exceptional entry which I believe the above
> > fuse_break_dax_layouts() needs to wait for, can you please elaborate
> > on how this can be avoided?
> >
>
> Hi Liubo,
>
> Can you please point to the exact lock you are referring to. I will
> check it out. Once we got rid of needing to take inode lock in
> reclaim path, that opended the door to do inline reclaim in fault
> path as well. But I was not aware of this exceptional entry lock.
Hi Vivek,
dax_iomap_{pte,pmd}_fault has called grab_mapping_entry to get a
locked entry, when this fault gets into inline reclaim, would
fuse_break_dax_layouts wait for the locked exceptional entry which is
locked in dax_iomap_{pte,pmd}_fault?
thanks,
liubo
next prev parent reply other threads:[~2020-03-27 22:06 UTC|newest]
Thread overview: 201+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-04 16:58 [PATCH 00/20] virtiofs: Add DAX support Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 01/20] dax: Modify bdev_dax_pgoff() to handle NULL bdev Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 02/20] dax: Create a range version of dax_layout_busy_page() Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 15:19 ` Ira Weiny
2020-03-10 15:19 ` [Virtio-fs] " Ira Weiny
2020-03-10 15:19 ` Ira Weiny
2020-03-10 20:29 ` Vivek Goyal
2020-03-10 20:29 ` [Virtio-fs] " Vivek Goyal
2020-03-10 20:29 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 03/20] virtio: Add get_shm_region method Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 10:53 ` Stefan Hajnoczi
2020-03-10 10:53 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-10 10:53 ` Stefan Hajnoczi
2020-03-04 16:58 ` [PATCH 04/20] virtio: Implement get_shm_region for PCI transport Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 11:04 ` Stefan Hajnoczi
2020-03-10 11:04 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-10 11:04 ` Stefan Hajnoczi
2020-03-10 18:19 ` Vivek Goyal
2020-03-10 18:19 ` [Virtio-fs] " Vivek Goyal
2020-03-10 18:19 ` Vivek Goyal
2020-03-11 17:34 ` Stefan Hajnoczi
2020-03-11 17:34 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-11 17:34 ` Stefan Hajnoczi
2020-03-11 19:29 ` Vivek Goyal
2020-03-11 19:29 ` [Virtio-fs] " Vivek Goyal
2020-03-11 19:29 ` Vivek Goyal
2020-03-10 11:12 ` Michael S. Tsirkin
2020-03-10 11:12 ` [Virtio-fs] " Michael S. Tsirkin
2020-03-10 11:12 ` Michael S. Tsirkin
2020-03-10 18:47 ` Vivek Goyal
2020-03-10 18:47 ` [Virtio-fs] " Vivek Goyal
2020-03-10 18:47 ` Vivek Goyal
2020-03-10 21:27 ` Michael S. Tsirkin
2020-03-10 21:27 ` [Virtio-fs] " Michael S. Tsirkin
2020-03-10 21:27 ` Michael S. Tsirkin
2020-03-04 16:58 ` [PATCH 05/20] virtio: Implement get_shm_region for MMIO transport Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 11:06 ` Stefan Hajnoczi
2020-03-10 11:06 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-10 11:06 ` Stefan Hajnoczi
2020-03-04 16:58 ` [PATCH 06/20] virtiofs: Provide a helper function for virtqueue initialization Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 14:10 ` Miklos Szeredi
2020-03-10 14:10 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 14:10 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 07/20] fuse: Get rid of no_mount_options Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 14:12 ` Miklos Szeredi
2020-03-10 14:12 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 14:12 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 08/20] fuse,virtiofs: Add a mount option to enable dax Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 08/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 08/20] fuse,virtiofs: " Vivek Goyal
2020-03-10 14:16 ` Miklos Szeredi
2020-03-10 14:16 ` [Virtio-fs] [PATCH 08/20] fuse, virtiofs: " Miklos Szeredi
2020-03-10 14:16 ` [PATCH 08/20] fuse,virtiofs: " Miklos Szeredi
2020-03-04 16:58 ` [PATCH 09/20] virtio_fs, dax: Set up virtio_fs dax_device Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 10/20] fuse,virtiofs: Keep a list of free dax memory ranges Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 10/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 10/20] fuse,virtiofs: " Vivek Goyal
2020-03-10 19:29 ` Miklos Szeredi
2020-03-10 19:29 ` [Virtio-fs] [PATCH 10/20] fuse, virtiofs: " Miklos Szeredi
2020-03-10 19:29 ` [PATCH 10/20] fuse,virtiofs: " Miklos Szeredi
2020-03-04 16:58 ` [PATCH 11/20] fuse: implement FUSE_INIT map_alignment field Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 19:31 ` Miklos Szeredi
2020-03-10 19:31 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 19:31 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 12/20] fuse: Introduce setupmapping/removemapping commands Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 19:49 ` Miklos Szeredi
2020-03-10 19:49 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 19:49 ` Miklos Szeredi
2020-03-10 20:33 ` Vivek Goyal
2020-03-10 20:33 ` [Virtio-fs] " Vivek Goyal
2020-03-10 20:33 ` Vivek Goyal
2020-03-11 7:03 ` Amir Goldstein
2020-03-11 7:03 ` [Virtio-fs] " Amir Goldstein
2020-03-11 7:03 ` Amir Goldstein
2020-03-11 14:19 ` Miklos Szeredi
2020-03-11 14:19 ` [Virtio-fs] " Miklos Szeredi
2020-03-11 14:19 ` Miklos Szeredi
2020-03-11 14:41 ` Vivek Goyal
2020-03-11 14:41 ` [Virtio-fs] " Vivek Goyal
2020-03-11 14:41 ` Vivek Goyal
2020-03-11 15:12 ` Miklos Szeredi
2020-03-11 15:12 ` [Virtio-fs] " Miklos Szeredi
2020-03-11 15:12 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 13/20] fuse, dax: Implement dax read/write operations Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-12 9:43 ` Miklos Szeredi
2020-03-12 9:43 ` [Virtio-fs] " Miklos Szeredi
2020-03-12 9:43 ` Miklos Szeredi
2020-03-12 16:02 ` Vivek Goyal
2020-03-12 16:02 ` [Virtio-fs] " Vivek Goyal
2020-03-12 16:02 ` Vivek Goyal
2020-03-13 10:18 ` Miklos Szeredi
2020-03-13 10:18 ` [Virtio-fs] " Miklos Szeredi
2020-03-13 10:18 ` Miklos Szeredi
2020-03-13 13:41 ` Vivek Goyal
2020-03-13 13:41 ` [Virtio-fs] " Vivek Goyal
2020-03-13 13:41 ` Vivek Goyal
2020-04-04 0:25 ` Liu Bo
2020-04-04 0:25 ` [Virtio-fs] " Liu Bo
2020-04-04 0:25 ` Liu Bo
2020-04-14 12:54 ` Vivek Goyal
2020-04-14 12:54 ` [Virtio-fs] " Vivek Goyal
2020-04-14 12:54 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 14/20] fuse,dax: add DAX mmap support Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 15/20] fuse, dax: Take ->i_mmap_sem lock during dax page fault Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 16/20] fuse,virtiofs: Define dax address space operations Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 16/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 16/20] fuse,virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 17/20] fuse,virtiofs: Maintain a list of busy elements Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 17/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 17/20] fuse,virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 18/20] fuse: Release file in process context Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 19/20] fuse: Take inode lock for dax inode truncation Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 20/20] fuse,virtiofs: Add logic to free up a memory range Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-03-11 5:16 ` Liu Bo
2020-03-11 5:16 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-11 5:16 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-11 12:59 ` Vivek Goyal
2020-03-11 12:59 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-03-11 12:59 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-03-11 17:24 ` Liu Bo
2020-03-11 17:24 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-11 17:24 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-26 0:09 ` Liu Bo
2020-03-26 0:09 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-26 0:09 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-27 14:01 ` Vivek Goyal
2020-03-27 14:01 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-03-27 14:01 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-03-27 22:06 ` Liu Bo [this message]
2020-03-27 22:06 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-27 22:06 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-04-14 19:30 ` Vivek Goyal
2020-04-14 19:30 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-04-14 19:30 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-04-15 17:22 ` Liu Bo
2020-04-15 17:22 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-04-15 17:22 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-04-16 19:05 ` Vivek Goyal
2020-04-16 19:05 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-04-16 19:05 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-04-17 18:05 ` Liu Bo
2020-04-17 18:05 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-04-17 18:05 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-11 5:22 ` [PATCH 00/20] virtiofs: Add DAX support Amir Goldstein
2020-03-11 5:22 ` [Virtio-fs] " Amir Goldstein
2020-03-11 5:22 ` Amir Goldstein
2020-03-11 13:09 ` Vivek Goyal
2020-03-11 13:09 ` [Virtio-fs] " Vivek Goyal
2020-03-11 13:09 ` Vivek Goyal
2020-03-11 18:48 ` Vivek Goyal
2020-03-11 18:48 ` [Virtio-fs] " Vivek Goyal
2020-03-11 18:48 ` Vivek Goyal
2020-03-11 19:32 ` Amir Goldstein
2020-03-11 19:32 ` [Virtio-fs] " Amir Goldstein
2020-03-11 19:32 ` Amir Goldstein
2020-03-11 19:39 ` Vivek Goyal
2020-03-11 19:39 ` [Virtio-fs] " Vivek Goyal
2020-03-11 19:39 ` Vivek Goyal
2020-03-11 13:38 ` Patrick Ohly
2020-03-11 13:38 ` [Virtio-fs] " Patrick Ohly
2020-03-11 13:38 ` Patrick Ohly
2020-03-16 13:02 ` Vivek Goyal
2020-03-16 13:02 ` [Virtio-fs] " Vivek Goyal
2020-03-16 13:02 ` Vivek Goyal
2020-03-17 8:28 ` Patrick Ohly
2020-03-17 8:28 ` [Virtio-fs] " Patrick Ohly
2020-03-17 8:28 ` Patrick Ohly
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