linux.git/include/linux/backing-dev.h, branch v6.12.80

writeback: fix false warning in inode_to_wb()

2025-04-25T08:47:49+00:00

commit 9e888998ea4d22257b07ce911576509486fa0667 upstream.

inode_to_wb() is used also for filesystems that don't support cgroup
writeback.  For these filesystems inode->i_wb is stable during the
lifetime of the inode (it points to bdi->wb) and there's no need to hold
locks protecting the inode->i_wb dereference.  Improve the warning in
inode_to_wb() to not trigger for these filesystems.

Link: https://lkml.kernel.org/r/20250412163914.3773459-3-agruenba@redhat.com
Fixes: aaa2cacf8184 ("writeback: add lockdep annotation to inode_to_wb()")
Signed-off-by: Jan Kara 
Signed-off-by: Andreas Gruenbacher 
Reviewed-by: Andreas Gruenbacher 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

writeback: move wb_wakeup_delayed defination to fs-writeback.c

2024-01-22T14:33:38+00:00

The wb_wakeup_delayed is only used in fs-writeback.c. Move it to
fs-writeback.c after defination of wb_wakeup and make it static.

Signed-off-by: Kemeng Shi 
Link: https://lore.kernel.org/r/20240118203339.764093-1-shikemeng@huaweicloud.com
Reviewed-by: Jan Kara 
Signed-off-by: Christian Brauner

writeback: remove unused delaration of bdi_async_bio_wq

2023-08-21T20:38:01+00:00

It seems it was introduced by commit d3f77dfdc718 ("blkcg: implement
REQ_CGROUP_PUNT") unintentionally, but the definition does not exist,
remove it.

Link: https://lkml.kernel.org/r/20230812110128.482650-1-xiujianfeng@huaweicloud.com
Signed-off-by: Xiu Jianfeng 
Acked-by: Tejun Heo 
Cc: Stefan Roesch 
Signed-off-by: Andrew Morton

mm: add bdi_set_min_ratio_no_scale() function

2022-11-30T23:59:06+00:00

This introduces bdi_set_min_ratio_no_scale(). It uses the max
granularity for the ratio. This function by the new sysfs knob
min_ratio_fine.

Link: https://lkml.kernel.org/r/20221119005215.3052436-19-shr@devkernel.io
Signed-off-by: Stefan Roesch 
Cc: Chris Mason 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton

mm: add bdi_set_max_ratio_no_scale() function

2022-11-30T23:59:06+00:00

This introduces bdi_set_max_ratio_no_scale(). It uses the max
granularity for the ratio. This function by the new sysfs knob
max_ratio_fine.

Link: https://lkml.kernel.org/r/20221119005215.3052436-16-shr@devkernel.io
Signed-off-by: Stefan Roesch 
Cc: Chris Mason 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton

mm: add bdi_set_min_bytes() function

2022-11-30T23:59:05+00:00

This introduces the bdi_set_min_bytes() function. The min_bytes function
does not store the min_bytes value. Instead it converts the min_bytes
value into the corresponding ratio value.

Link: https://lkml.kernel.org/r/20221119005215.3052436-13-shr@devkernel.io
Signed-off-by: Stefan Roesch 
Cc: Chris Mason 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton

mm: add bdi_get_min_bytes() function

2022-11-30T23:59:05+00:00

This adds a function to return the specified value for min_bytes. It
converts the stored min_ratio of the bdi to the corresponding bytes
value. This is an approximation as it is based on the value that is
returned by global_dirty_limits(), which can change. The returned
value can be different than the value when the min_bytes value was set.

Link: https://lkml.kernel.org/r/20221119005215.3052436-11-shr@devkernel.io
Signed-off-by: Stefan Roesch 
Cc: Chris Mason 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton

mm: add bdi_set_max_bytes() function

2022-11-30T23:59:04+00:00

This introduces the bdi_set_max_bytes() function. The max_bytes function
does not store the max_bytes value. Instead it converts the max_bytes
value into the corresponding ratio value.

Link: https://lkml.kernel.org/r/20221119005215.3052436-8-shr@devkernel.io
Signed-off-by: Stefan Roesch 
Cc: Chris Mason 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton

mm: add bdi_get_max_bytes() function

2022-11-30T23:59:04+00:00

This adds a function to return the specified value for max_bytes. It
converts the stored max_ratio of the bdi to the corresponding bytes
value. It introduces the bdi_get_bytes helper function to do the
conversion. This is an approximation as it is based on the value that is
returned by global_dirty_limits(), which can change. The helper function
will also be used by the min_bytes bdi knob.

Link: https://lkml.kernel.org/r/20221119005215.3052436-6-shr@devkernel.io
Signed-off-by: Stefan Roesch 
Cc: Chris Mason 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton

mm: use part per 1000000 for bdi ratios

2022-11-30T23:59:03+00:00

To get finer granularity for ratio calculations use part per million
instead of percentiles. This is especially important if we want to
automatically convert byte values to ratios. Otherwise the values that
are actually used can be quite different. This is also important for
machines with more main memory (1% of 256GB is already 2.5GB).

Link: https://lkml.kernel.org/r/20221119005215.3052436-5-shr@devkernel.io
Signed-off-by: Stefan Roesch 
Cc: Chris Mason 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton