From fbf96e67255eed8445137a9af781f2022e9ba025 Mon Sep 17 00:00:00 2001 From: Olaf Hering Date: Sat, 2 Apr 2011 15:50:19 +0100 Subject: [PATCH] xentrace: correct formula to calculate t_info_pages The current formula to calculate t_info_pages, based on the initial code, is slightly incorrect. It may allocate more than needed. Each cpu has some pages/mfns stored as uint32_t. That list is stored with an offset at tinfo. Signed-off-by: Olaf Hering Acked-by: George Dunlap --- xen/common/trace.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/xen/common/trace.c b/xen/common/trace.c index a1214a0b32..a1452ece45 100644 --- a/xen/common/trace.c +++ b/xen/common/trace.c @@ -110,7 +110,7 @@ static int calculate_tbuf_size(unsigned int pages) { struct t_buf dummy; typeof(dummy.prod) size; - unsigned int t_info_words, t_info_bytes; + unsigned int t_info_words; /* force maximum value for an unsigned type */ size = -1; @@ -125,9 +125,8 @@ static int calculate_tbuf_size(unsigned int pages) pages = size; } - t_info_words = num_online_cpus() * pages + t_info_first_offset; - t_info_bytes = t_info_words * sizeof(uint32_t); - t_info_pages = PFN_UP(t_info_bytes); + t_info_words = num_online_cpus() * pages * sizeof(uint32_t); + t_info_pages = PFN_UP(t_info_first_offset + t_info_words); printk(XENLOG_INFO "xentrace: requesting %u t_info pages " "for %u trace pages on %u cpus\n", t_info_pages, pages, num_online_cpus()); -- 2.39.5