Message ID | 20240426143903.1305919-1-houtao@huaweicloud.com (mailing list archive) |
---|---|
Headers | show |
Series | virtiofs: fix the warning for kernel direct IO | expand |
Hi, Tao, On 4/26/24 10:39 PM, Hou Tao wrote: > From: Hou Tao <houtao1@huawei.com> > > Hi, > > The patch set aims to fix the warning related to an abnormal size > parameter of kmalloc() in virtiofs. Patch #1 fixes it by introducing > use_pages_for_kvec_io option in fuse_conn and enabling it in virtiofs. > Beside the abnormal size parameter for kmalloc, the gfp parameter is > also questionable: GFP_ATOMIC is used even when the allocation occurs > in a kworker context. Patch #2 fixes it by using GFP_NOFS when the > allocation is initiated by the kworker. For more details, please check > the individual patches. > > As usual, comments are always welcome. > > Change Log: > > v3: > * introduce use_pages_for_kvec_io for virtiofs. When the option is > enabled, fuse will use iov_iter_extract_pages() to construct a page > array and pass the pages array instead of a pointer to virtiofs. > The benefit is twofold: the length of the data passed to virtiofs is > limited by max_pages, and there is no memory copy compared with v2. > > v2: https://lore.kernel.org/linux-fsdevel/20240228144126.2864064-1-houtao@huaweicloud.com/ > * limit the length of ITER_KVEC dio by max_pages instead of the > newly-introduced max_nopage_rw. Using max_pages make the ITER_KVEC > dio being consistent with other rw operations. > * replace kmalloc-allocated bounce buffer by using a bounce buffer > backed by scattered pages when the length of the bounce buffer for > KVEC_ITER dio is larger than PAG_SIZE, so even on hosts with > fragmented memory, the KVEC_ITER dio can be handled normally by > virtiofs. (Bernd Schubert) > * merge the GFP_NOFS patch [1] into this patch-set and use > memalloc_nofs_{save|restore}+GFP_KERNEL instead of GFP_NOFS > (Benjamin Coddington) > > v1: https://lore.kernel.org/linux-fsdevel/20240103105929.1902658-1-houtao@huaweicloud.com/ > > [1]: https://lore.kernel.org/linux-fsdevel/20240105105305.4052672-1-houtao@huaweicloud.com/ > > Hou Tao (2): > virtiofs: use pages instead of pointer for kernel direct IO > virtiofs: use GFP_NOFS when enqueuing request through kworker > > fs/fuse/file.c | 12 ++++++++---- > fs/fuse/fuse_i.h | 3 +++ > fs/fuse/virtio_fs.c | 25 ++++++++++++++++--------- > 3 files changed, 27 insertions(+), 13 deletions(-) > We also encountered the same issue as [1] these days when attempting to insmod a module with ~6MB size, which is upon a virtiofs filesystem. It would be much helpful if this issue has a standard fix in the upstream. I see there will be v4 when reading through the mailing thread. Glad to know if there's any update to this series. [1] https://lore.kernel.org/linux-fsdevel/20240103105929.1902658-1-houtao@huaweicloud.com/
Hi, On 8/14/2024 2:34 PM, Jingbo Xu wrote: > Hi, Tao, > > On 4/26/24 10:39 PM, Hou Tao wrote: >> From: Hou Tao <houtao1@huawei.com> >> >> Hi, >> >> The patch set aims to fix the warning related to an abnormal size >> parameter of kmalloc() in virtiofs. Patch #1 fixes it by introducing >> use_pages_for_kvec_io option in fuse_conn and enabling it in virtiofs. >> Beside the abnormal size parameter for kmalloc, the gfp parameter is >> also questionable: GFP_ATOMIC is used even when the allocation occurs >> in a kworker context. Patch #2 fixes it by using GFP_NOFS when the >> allocation is initiated by the kworker. For more details, please check >> the individual patches. >> >> As usual, comments are always welcome. >> >> Change Log: >> >> v3: >> * introduce use_pages_for_kvec_io for virtiofs. When the option is >> enabled, fuse will use iov_iter_extract_pages() to construct a page >> array and pass the pages array instead of a pointer to virtiofs. >> The benefit is twofold: the length of the data passed to virtiofs is >> limited by max_pages, and there is no memory copy compared with v2. >> >> v2: https://lore.kernel.org/linux-fsdevel/20240228144126.2864064-1-houtao@huaweicloud.com/ >> * limit the length of ITER_KVEC dio by max_pages instead of the >> newly-introduced max_nopage_rw. Using max_pages make the ITER_KVEC >> dio being consistent with other rw operations. >> * replace kmalloc-allocated bounce buffer by using a bounce buffer >> backed by scattered pages when the length of the bounce buffer for >> KVEC_ITER dio is larger than PAG_SIZE, so even on hosts with >> fragmented memory, the KVEC_ITER dio can be handled normally by >> virtiofs. (Bernd Schubert) >> * merge the GFP_NOFS patch [1] into this patch-set and use >> memalloc_nofs_{save|restore}+GFP_KERNEL instead of GFP_NOFS >> (Benjamin Coddington) >> >> v1: https://lore.kernel.org/linux-fsdevel/20240103105929.1902658-1-houtao@huaweicloud.com/ >> >> [1]: https://lore.kernel.org/linux-fsdevel/20240105105305.4052672-1-houtao@huaweicloud.com/ >> >> Hou Tao (2): >> virtiofs: use pages instead of pointer for kernel direct IO >> virtiofs: use GFP_NOFS when enqueuing request through kworker >> >> fs/fuse/file.c | 12 ++++++++---- >> fs/fuse/fuse_i.h | 3 +++ >> fs/fuse/virtio_fs.c | 25 ++++++++++++++++--------- >> 3 files changed, 27 insertions(+), 13 deletions(-) >> > We also encountered the same issue as [1] these days when attempting to > insmod a module with ~6MB size, which is upon a virtiofs filesystem. > > It would be much helpful if this issue has a standard fix in the > upstream. I see there will be v4 when reading through the mailing > thread. Glad to know if there's any update to this series. Being busy with other stuff these days. I hope to send v4 before next weekend. > > [1] > https://lore.kernel.org/linux-fsdevel/20240103105929.1902658-1-houtao@huaweicloud.com/ >
On 8/14/24 3:46 PM, Hou Tao wrote: > Hi, > > On 8/14/2024 2:34 PM, Jingbo Xu wrote: >> Hi, Tao, >> >> On 4/26/24 10:39 PM, Hou Tao wrote: >>> From: Hou Tao <houtao1@huawei.com> >>> >>> Hi, >>> >>> The patch set aims to fix the warning related to an abnormal size >>> parameter of kmalloc() in virtiofs. Patch #1 fixes it by introducing >>> use_pages_for_kvec_io option in fuse_conn and enabling it in virtiofs. >>> Beside the abnormal size parameter for kmalloc, the gfp parameter is >>> also questionable: GFP_ATOMIC is used even when the allocation occurs >>> in a kworker context. Patch #2 fixes it by using GFP_NOFS when the >>> allocation is initiated by the kworker. For more details, please check >>> the individual patches. >>> >>> As usual, comments are always welcome. >>> >>> Change Log: >>> >>> v3: >>> * introduce use_pages_for_kvec_io for virtiofs. When the option is >>> enabled, fuse will use iov_iter_extract_pages() to construct a page >>> array and pass the pages array instead of a pointer to virtiofs. >>> The benefit is twofold: the length of the data passed to virtiofs is >>> limited by max_pages, and there is no memory copy compared with v2. >>> >>> v2: https://lore.kernel.org/linux-fsdevel/20240228144126.2864064-1-houtao@huaweicloud.com/ >>> * limit the length of ITER_KVEC dio by max_pages instead of the >>> newly-introduced max_nopage_rw. Using max_pages make the ITER_KVEC >>> dio being consistent with other rw operations. >>> * replace kmalloc-allocated bounce buffer by using a bounce buffer >>> backed by scattered pages when the length of the bounce buffer for >>> KVEC_ITER dio is larger than PAG_SIZE, so even on hosts with >>> fragmented memory, the KVEC_ITER dio can be handled normally by >>> virtiofs. (Bernd Schubert) >>> * merge the GFP_NOFS patch [1] into this patch-set and use >>> memalloc_nofs_{save|restore}+GFP_KERNEL instead of GFP_NOFS >>> (Benjamin Coddington) >>> >>> v1: https://lore.kernel.org/linux-fsdevel/20240103105929.1902658-1-houtao@huaweicloud.com/ >>> >>> [1]: https://lore.kernel.org/linux-fsdevel/20240105105305.4052672-1-houtao@huaweicloud.com/ >>> >>> Hou Tao (2): >>> virtiofs: use pages instead of pointer for kernel direct IO >>> virtiofs: use GFP_NOFS when enqueuing request through kworker >>> >>> fs/fuse/file.c | 12 ++++++++---- >>> fs/fuse/fuse_i.h | 3 +++ >>> fs/fuse/virtio_fs.c | 25 ++++++++++++++++--------- >>> 3 files changed, 27 insertions(+), 13 deletions(-) >>> >> We also encountered the same issue as [1] these days when attempting to >> insmod a module with ~6MB size, which is upon a virtiofs filesystem. >> >> It would be much helpful if this issue has a standard fix in the >> upstream. I see there will be v4 when reading through the mailing >> thread. Glad to know if there's any update to this series. > > Being busy with other stuff these days. I hope to send v4 before next > weekend. Many thanks, Tao.
From: Hou Tao <houtao1@huawei.com> Hi, The patch set aims to fix the warning related to an abnormal size parameter of kmalloc() in virtiofs. Patch #1 fixes it by introducing use_pages_for_kvec_io option in fuse_conn and enabling it in virtiofs. Beside the abnormal size parameter for kmalloc, the gfp parameter is also questionable: GFP_ATOMIC is used even when the allocation occurs in a kworker context. Patch #2 fixes it by using GFP_NOFS when the allocation is initiated by the kworker. For more details, please check the individual patches. As usual, comments are always welcome. Change Log: v3: * introduce use_pages_for_kvec_io for virtiofs. When the option is enabled, fuse will use iov_iter_extract_pages() to construct a page array and pass the pages array instead of a pointer to virtiofs. The benefit is twofold: the length of the data passed to virtiofs is limited by max_pages, and there is no memory copy compared with v2. v2: https://lore.kernel.org/linux-fsdevel/20240228144126.2864064-1-houtao@huaweicloud.com/ * limit the length of ITER_KVEC dio by max_pages instead of the newly-introduced max_nopage_rw. Using max_pages make the ITER_KVEC dio being consistent with other rw operations. * replace kmalloc-allocated bounce buffer by using a bounce buffer backed by scattered pages when the length of the bounce buffer for KVEC_ITER dio is larger than PAG_SIZE, so even on hosts with fragmented memory, the KVEC_ITER dio can be handled normally by virtiofs. (Bernd Schubert) * merge the GFP_NOFS patch [1] into this patch-set and use memalloc_nofs_{save|restore}+GFP_KERNEL instead of GFP_NOFS (Benjamin Coddington) v1: https://lore.kernel.org/linux-fsdevel/20240103105929.1902658-1-houtao@huaweicloud.com/ [1]: https://lore.kernel.org/linux-fsdevel/20240105105305.4052672-1-houtao@huaweicloud.com/ Hou Tao (2): virtiofs: use pages instead of pointer for kernel direct IO virtiofs: use GFP_NOFS when enqueuing request through kworker fs/fuse/file.c | 12 ++++++++---- fs/fuse/fuse_i.h | 3 +++ fs/fuse/virtio_fs.c | 25 ++++++++++++++++--------- 3 files changed, 27 insertions(+), 13 deletions(-)