mm, page_alloc: remove MIGRATE_RESERVE

[firefly-linux-kernel-4.4.55.git] / mm / readahead.c

diff --git a/mm/readahead.c b/mm/readahead.c
index 24682f6f4cfd1d84d7245faea0da78e7fd17e716..998ad592f408332135d107c442e0beb879eb5d58 100644 (file)
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -213,7 +213,7 @@ int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
        if (unlikely(!mapping->a_ops->readpage && !mapping->a_ops->readpages))
                return -EINVAL;
 
-       nr_to_read = max_sane_readahead(nr_to_read);
+       nr_to_read = min(nr_to_read, inode_to_bdi(mapping->host)->ra_pages);
        while (nr_to_read) {
                int err;
 
@@ -232,16 +232,6 @@ int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
        return 0;
 }
 
-#define MAX_READAHEAD   ((512*4096)/PAGE_CACHE_SIZE)
-/*
- * Given a desired number of PAGE_CACHE_SIZE readahead pages, return a
- * sensible upper limit.
- */
-unsigned long max_sane_readahead(unsigned long nr)
-{
-       return min(nr, MAX_READAHEAD);
-}
-
 /*
  * Set the initial window size, round to next power of 2 and square
  * for small size, x 4 for medium, and x 2 for large
@@ -380,7 +370,7 @@ ondemand_readahead(struct address_space *mapping,
                   bool hit_readahead_marker, pgoff_t offset,
                   unsigned long req_size)
 {
-       unsigned long max = max_sane_readahead(ra->ra_pages);
+       unsigned long max = ra->ra_pages;
        pgoff_t prev_offset;
 
        /*