[PATCH 8/9] perf annotate: Fix off by one symbol hist size allocation and hit accounting

From: Arnaldo Carvalho de Melo
Date: Fri Mar 30 2012 - 12:11:13 EST

From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

We were not noticing it because symbol__inc_addr_samples was erroneously
dropping samples that hit the last byte in a function.

Working on a fix for a problem reported by David Miller, Stephane
Eranian and Sorin Dumitru, where addresses < sym->start were causing
problems, I noticed this other problem.

Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: David Miller <davem@xxxxxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Sorin Dumitru <dumitru.sorin87@xxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-pqjaq4cr1xs2xen73pjhbav4@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
tools/perf/util/annotate.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 31ba2a2..199f69e 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -28,8 +28,8 @@ int symbol__annotate_init(struct map *map __used, struct symbol *sym)
int symbol__alloc_hist(struct symbol *sym)
struct annotation *notes = symbol__annotation(sym);
- size_t sizeof_sym_hist = (sizeof(struct sym_hist) +
- (sym->end - sym->start) * sizeof(u64));
+ const size_t size = sym->end - sym->start + 1;
+ size_t sizeof_sym_hist = (sizeof(struct sym_hist) + size * sizeof(u64));

notes->src = zalloc(sizeof(*notes->src) + symbol_conf.nr_events * sizeof_sym_hist);
if (notes->src == NULL)
@@ -64,7 +64,7 @@ int symbol__inc_addr_samples(struct symbol *sym, struct map *map,

pr_debug3("%s: addr=%#" PRIx64 "\n", __func__, map->unmap_ip(map, addr));

- if (addr >= sym->end)
+ if (addr > sym->end)
return 0;

offset = addr - sym->start;

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