The patch titled
Subject: mm/readahead: make do_page_cache_ra take a readahead_control
has been added to the -mm tree. Its filename is
mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm/readahead: make do_page_cache_ra take a readahead_control
Rename __do_page_cache_readahead() to do_page_cache_ra() and call it
directly from ondemand_readahead() instead of indirecting via ra_submit().
Link: https://lkml.kernel.org/r/20200903140844.14194-5-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/internal.h | 11 +++++------
mm/readahead.c | 28 +++++++++++++++-------------
2 files changed, 20 insertions(+), 19 deletions(-)
--- a/mm/internal.h~mm-readahead-make-do_page_cache_ra-take-a-readahead_control
+++ a/mm/internal.h
@@ -51,18 +51,17 @@ void unmap_page_range(struct mmu_gather
void force_page_cache_readahead(struct address_space *, struct file *,
pgoff_t index, unsigned long nr_to_read);
-void __do_page_cache_readahead(struct address_space *, struct file *,
- pgoff_t index, unsigned long nr_to_read,
- unsigned long lookahead_size);
+void do_page_cache_ra(struct readahead_control *,
+ unsigned long nr_to_read, unsigned long lookahead_size);
/*
* Submit IO for the read-ahead request in file_ra_state.
*/
static inline void ra_submit(struct file_ra_state *ra,
- struct address_space *mapping, struct file *filp)
+ struct address_space *mapping, struct file *file)
{
- __do_page_cache_readahead(mapping, filp,
- ra->start, ra->size, ra->async_size);
+ DEFINE_READAHEAD(ractl, file, mapping, ra->start);
+ do_page_cache_ra(&ractl, ra->size, ra->async_size);
}
/**
--- a/mm/readahead.c~mm-readahead-make-do_page_cache_ra-take-a-readahead_control
+++ a/mm/readahead.c
@@ -241,17 +241,16 @@ void page_cache_ra_unbounded(struct read
EXPORT_SYMBOL_GPL(page_cache_ra_unbounded);
/*
- * __do_page_cache_readahead() actually reads a chunk of disk. It allocates
+ * do_page_cache_ra() actually reads a chunk of disk. It allocates
* the pages first, then submits them for I/O. This avoids the very bad
* behaviour which would occur if page allocations are causing VM writeback.
* We really don't want to intermingle reads and writes like that.
*/
-void __do_page_cache_readahead(struct address_space *mapping,
- struct file *file, pgoff_t index, unsigned long nr_to_read,
- unsigned long lookahead_size)
+void do_page_cache_ra(struct readahead_control *ractl,
+ unsigned long nr_to_read, unsigned long lookahead_size)
{
- DEFINE_READAHEAD(ractl, file, mapping, index);
- struct inode *inode = mapping->host;
+ struct inode *inode = ractl->mapping->host;
+ unsigned long index = readahead_index(ractl);
loff_t isize = i_size_read(inode);
pgoff_t end_index; /* The last page we want to read */
@@ -265,7 +264,7 @@ void __do_page_cache_readahead(struct ad
if (nr_to_read > end_index - index)
nr_to_read = end_index - index + 1;
- page_cache_ra_unbounded(&ractl, nr_to_read, lookahead_size);
+ page_cache_ra_unbounded(ractl, nr_to_read, lookahead_size);
}
/*
@@ -273,10 +272,11 @@ void __do_page_cache_readahead(struct ad
* memory at once.
*/
void force_page_cache_readahead(struct address_space *mapping,
- struct file *filp, pgoff_t index, unsigned long nr_to_read)
+ struct file *file, pgoff_t index, unsigned long nr_to_read)
{
+ DEFINE_READAHEAD(ractl, file, mapping, index);
struct backing_dev_info *bdi = inode_to_bdi(mapping->host);
- struct file_ra_state *ra = &filp->f_ra;
+ struct file_ra_state *ra = &file->f_ra;
unsigned long max_pages;
if (unlikely(!mapping->a_ops->readpage && !mapping->a_ops->readpages &&
@@ -294,7 +294,7 @@ void force_page_cache_readahead(struct a
if (this_chunk > nr_to_read)
this_chunk = nr_to_read;
- __do_page_cache_readahead(mapping, filp, index, this_chunk, 0);
+ do_page_cache_ra(&ractl, this_chunk, 0);
index += this_chunk;
nr_to_read -= this_chunk;
@@ -432,10 +432,11 @@ static int try_context_readahead(struct
* A minimal readahead algorithm for trivial sequential/random reads.
*/
static void ondemand_readahead(struct address_space *mapping,
- struct file_ra_state *ra, struct file *filp,
+ struct file_ra_state *ra, struct file *file,
bool hit_readahead_marker, pgoff_t index,
unsigned long req_size)
{
+ DEFINE_READAHEAD(ractl, file, mapping, index);
struct backing_dev_info *bdi = inode_to_bdi(mapping->host);
unsigned long max_pages = ra->ra_pages;
unsigned long add_pages;
@@ -516,7 +517,7 @@ static void ondemand_readahead(struct ad
* standalone, small random read
* Read as is, and do not pollute the readahead state.
*/
- __do_page_cache_readahead(mapping, filp, index, req_size, 0);
+ do_page_cache_ra(&ractl, req_size, 0);
return;
initial_readahead:
@@ -542,7 +543,8 @@ readit:
}
}
- ra_submit(ra, mapping, filp);
+ ractl._index = ra->start;
+ do_page_cache_ra(&ractl, ra->size, ra->async_size);
}
/**
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-debug-do-not-dereference-i_ino-blindly.patch
mm-account-pmd-tables-like-pte-tables.patch
mm-move-pagedoublemap-bit.patch
mm-simplify-pagedoublemap-with-pf_second-policy.patch
xarray-add-xa_get_order.patch
xarray-add-xas_split.patch
mm-filemap-fix-storing-to-a-thp-shadow-entry.patch
mm-readahead-add-define_readahead.patch
mm-readahead-make-page_cache_ra_unbounded-take-a-readahead_control.patch
mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
mm-readahead-add-page_cache_sync_ra-and-page_cache_async_ra.patch
harden-autofs-ioctl-table.patch
