Re: [RFC v2 04/14] readahead: set file_ra_state->ra_pages to be at least mapping_min_order

From: Hannes Reinecke
Date: Tue Feb 13 2024 - 10:01:38 EST


On 2/13/24 10:37, Pankaj Raghav (Samsung) wrote:
From: Luis Chamberlain <mcgrof@xxxxxxxxxx>

Set the file_ra_state->ra_pages in file_ra_state_init() to be at least
mapping_min_order of pages if the bdi->ra_pages is less than that.

Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
---
mm/readahead.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/mm/readahead.c b/mm/readahead.c
index 2648ec4f0494..4fa7d0e65706 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -138,7 +138,12 @@
void
file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping)
{
+ unsigned int min_nrpages = mapping_min_folio_nrpages(mapping);
+ unsigned int max_pages = inode_to_bdi(mapping->host)->io_pages;
+
ra->ra_pages = inode_to_bdi(mapping->host)->ra_pages;
+ if (ra->ra_pages < min_nrpages && min_nrpages < max_pages)
+ ra->ra_pages = min_nrpages;
ra->prev_pos = -1;
}
EXPORT_SYMBOL_GPL(file_ra_state_init);

Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes