Mesa (master): disk_cache: use block size rather than file size

[Timothy Arceri]

Module: Mesa
Branch: master
Commit: 4e1f3afea9bdeddb0d21f00d25319bce580d80c3
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=4e1f3afea9bdeddb0d21f00d25319bce580d80c3

Author: Timothy Arceri <tarceri at itsqueeze.com>
Date:   Thu Apr 27 11:15:30 2017 +1000

disk_cache: use block size rather than file size

The majority of cache files are less than 1kb this resulted in us
greatly miscalculating the amount of disk space used by the cache.

Using the number of blocks allocated to the file is more
conservative and less likely to cause issues.

This change will result in cache sizes being miscalculated further
until old items added with the previous calculation have all been
removed. However I don't see anyway around that, the previous
patch should help limit that problem.

Cc: "17.1" <mesa-stable at lists.freedesktop.org>
Reviewed-and-Tested-by: Michel Dänzer <michel.daenzer at amd.com>

---

 src/util/disk_cache.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/util/disk_cache.c b/src/util/disk_cache.c
index 9fd7b96adc..cc9faff013 100644
--- a/src/util/disk_cache.c
+++ b/src/util/disk_cache.c
@@ -532,7 +532,7 @@ unlink_lru_file_from_directory(const char *path)
    unlink(filename);
    free (filename);
 
-   return sb.st_size;
+   return sb.st_blocks * 512;
 }
 
 /* Is entry a directory with a two-character name, (and not the
@@ -637,8 +637,8 @@ disk_cache_remove(struct disk_cache *cache, const cache_key key)
    unlink(filename);
    free(filename);
 
-   if (sb.st_size)
-      p_atomic_add(cache->size, - (uint64_t)sb.st_size);
+   if (sb.st_blocks)
+      p_atomic_add(cache->size, - (uint64_t)sb.st_blocks * 512);
 }
 
 static ssize_t
@@ -880,8 +880,14 @@ cache_put(void *job, int thread_index)
       goto done;
    }
 
-   file_size += cf_data_size + dc_job->cache->driver_keys_blob_size;
-   p_atomic_add(dc_job->cache->size, file_size);
+   struct stat sb;
+   if (stat(filename, &sb) == -1) {
+      /* Something went wrong remove the file */
+      unlink(filename);
+      goto done;
+   }
+
+   p_atomic_add(dc_job->cache->size, sb.st_blocks * 512);
 
  done:
    if (fd_final != -1)