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| author | Jiri Kosina <jkosina@suse.cz> | 2013-12-19 15:08:03 +0100 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2013-12-19 15:08:32 +0100 |
| commit | e23c34bb41da65f354fb7eee04300c56ee48f60c (patch) | |
| tree | 549fbe449d55273b81ef104a9755109bf4ae7817 /mm/readahead.c | |
| parent | b481c2cb3534c85dca625973b33eba15f9af3e4c (diff) | |
| parent | 319e2e3f63c348a9b66db4667efa73178e18b17d (diff) | |
Merge branch 'master' into for-next
Sync with Linus' tree to be able to apply fixes on top of newer things
in tree (efi-stub).
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'mm/readahead.c')
| -rw-r--r-- | mm/readahead.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/mm/readahead.c b/mm/readahead.c index 829a77c62834..7cdbb44aa90b 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -371,10 +371,10 @@ static int try_context_readahead(struct address_space *mapping, size = count_history_pages(mapping, ra, offset, max); /* - * no history pages: + * not enough history pages: * it could be a random read */ - if (!size) + if (size <= req_size) return 0; /* @@ -385,8 +385,8 @@ static int try_context_readahead(struct address_space *mapping, size *= 2; ra->start = offset; - ra->size = get_init_ra_size(size + req_size, max); - ra->async_size = ra->size; + ra->size = min(size + req_size, max); + ra->async_size = 1; return 1; } @@ -401,6 +401,7 @@ ondemand_readahead(struct address_space *mapping, unsigned long req_size) { unsigned long max = max_sane_readahead(ra->ra_pages); + pgoff_t prev_offset; /* * start of file @@ -452,8 +453,11 @@ ondemand_readahead(struct address_space *mapping, /* * sequential cache miss + * trivial case: (offset - prev_offset) == 1 + * unaligned reads: (offset - prev_offset) == 0 */ - if (offset - (ra->prev_pos >> PAGE_CACHE_SHIFT) <= 1UL) + prev_offset = (unsigned long long)ra->prev_pos >> PAGE_CACHE_SHIFT; + if (offset - prev_offset <= 1UL) goto initial_readahead; /* @@ -569,7 +573,7 @@ static ssize_t do_readahead(struct address_space *mapping, struct file *filp, pgoff_t index, unsigned long nr) { - if (!mapping || !mapping->a_ops || !mapping->a_ops->readpage) + if (!mapping || !mapping->a_ops) return -EINVAL; force_page_cache_readahead(mapping, filp, index, nr); |