[PATCH 3.16 071/305] perf tools: Fix perf regs mask generation

Ben Hutchings
2016-08-14T18:00:37Z

From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>

commit f47822078dece7189cad0a5f472f148e5e916736 upstream.

On some architectures (powerpc in particular), the number of registers
exceeds what can be represented in an integer bitmask. Ensure we
generate the proper bitmask on such platforms.

Fixes: 71ad0f5e4 ("perf tools: Support for DWARF CFI unwinding on post processing")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
tools/perf/util/perf_regs.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/tools/perf/util/perf_regs.c
+++ b/tools/perf/util/perf_regs.c
@@ -7,18 +7,18 @@ int perf_reg_value(u64 *valp, struct reg
int i, idx = 0;
u64 mask = regs->mask;

- if (regs->cache_mask & (1 << id))
+ if (regs->cache_mask & (1ULL << id))
goto out;

- if (!(mask & (1 << id)))
+ if (!(mask & (1ULL << id)))
return -EINVAL;

for (i = 0; i < id; i++) {
- if (mask & (1 << i))
+ if (mask & (1ULL << i))
idx++;
}

- regs->cache_mask |= (1 << id);
+ regs->cache_mask |= (1ULL << id);
regs->cache_regs[id] = regs->regs[idx];