ALSA: pcm: potential uninitialized return values

[pandora-kernel.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 98cd090..62bfbd9 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -560,7 +560,7 @@ static unsigned long bdi_position_ratio(struct backing_dev_info *bdi,
         */
        setpoint = (freerun + limit) / 2;
        x = div64_s64(((s64)setpoint - (s64)dirty) << RATELIMIT_CALC_SHIFT,
-                   limit - setpoint + 1);
+                     (limit - setpoint) | 1);
        pos_ratio = x;
        pos_ratio = pos_ratio * x >> RATELIMIT_CALC_SHIFT;
        pos_ratio = pos_ratio * x >> RATELIMIT_CALC_SHIFT;
@@ -611,7 +611,7 @@ static unsigned long bdi_position_ratio(struct backing_dev_info *bdi,
         * scale global setpoint to bdi's:
         *      bdi_setpoint = setpoint * bdi_thresh / thresh
         */
-       x = div_u64((u64)bdi_thresh << 16, thresh + 1);
+       x = div_u64((u64)bdi_thresh << 16, thresh | 1);
        bdi_setpoint = setpoint * (u64)x >> 16;
        /*
         * Use span=(8*write_bw) in single bdi case as indicated by
@@ -626,7 +626,7 @@ static unsigned long bdi_position_ratio(struct backing_dev_info *bdi,
 
        if (bdi_dirty < x_intercept - span / 4) {
                pos_ratio = div64_u64(pos_ratio * (x_intercept - bdi_dirty),
-                                   x_intercept - bdi_setpoint + 1);
+                                     (x_intercept - bdi_setpoint) | 1);
        } else
                pos_ratio /= 4;
 
@@ -661,8 +661,11 @@ static void bdi_update_write_bandwidth(struct backing_dev_info *bdi,
         *                   bw * elapsed + write_bandwidth * (period - elapsed)
         * write_bandwidth = ---------------------------------------------------
         *                                          period
+        *
+        * @written may have decreased due to account_page_redirty().
+        * Avoid underflowing @bw calculation.
         */
-       bw = written - bdi->written_stamp;
+       bw = written - min(written, bdi->written_stamp);
        bw *= HZ;
        if (unlikely(elapsed > period)) {
                do_div(bw, elapsed);