From 7fb0e1a65075a871c58cbcf8c877d1f9ae5cd83c Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Fri, 27 Mar 2015 09:10:12 -0700 Subject: [PATCH] Drivers: hv: hv_balloon: eliminate jumps in piecewiese linear floor function Commit 79208c57da53 ("Drivers: hv: hv_balloon: Make adjustments in computing the floor") was inacurate as it introduced a jump in our piecewiese linear 'floor' function: At 2048MB we have: Left limit: 104 + 2048/8 = 360 Right limit: 256 + 2048/16 = 384 (so the right value is 232) We now have to make an adjustment at 8192 boundary: 232 + 8192/16 = 744 512 + 8192/32 = 768 (so the right value is 488) Suggested-by: Laszlo Ersek Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- drivers/hv/hv_balloon.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 99afef9393aa..4f5323cedab3 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -976,8 +976,8 @@ static unsigned long compute_balloon_floor(void) * 128 72 (1/2) * 512 168 (1/4) * 2048 360 (1/8) - * 8192 768 (1/16) - * 32768 1536 (1/32) + * 8192 744 (1/16) + * 32768 1512 (1/32) */ if (totalram_pages < MB2PAGES(128)) min_pages = MB2PAGES(8) + (totalram_pages >> 1); @@ -986,9 +986,9 @@ static unsigned long compute_balloon_floor(void) else if (totalram_pages < MB2PAGES(2048)) min_pages = MB2PAGES(104) + (totalram_pages >> 3); else if (totalram_pages < MB2PAGES(8192)) - min_pages = MB2PAGES(256) + (totalram_pages >> 4); + min_pages = MB2PAGES(232) + (totalram_pages >> 4); else - min_pages = MB2PAGES(512) + (totalram_pages >> 5); + min_pages = MB2PAGES(488) + (totalram_pages >> 5); #undef MB2PAGES return min_pages; }