* Re: [PATCH] perf timechart: Fix SIBGUS error on sparc64
2015-03-24 20:14 [PATCH] perf timechart: Fix SIBGUS error on sparc64 David Ahern
@ 2015-03-24 21:15 ` Arnaldo Carvalho de Melo
2015-03-24 21:28 ` David Ahern
2015-03-27 7:39 ` [tip:perf/core] " tip-bot for David Ahern
1 sibling, 1 reply; 4+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-03-24 21:15 UTC (permalink / raw)
To: David Ahern; +Cc: linux-kernel
Em Tue, Mar 24, 2015 at 04:14:09PM -0400, David Ahern escreveu:
> perf timechart -T on sparc64 is terminating due to SIGBUS. Backtrace:
>
> Program received signal SIGBUS, Bus error.
> 0x0000000000173d7c in perf_evsel__intval (evsel=<value optimized out>, sample=0x7feffffda28, name=0x289b28 "prev_state")
> at util/evsel.c:1918
> 1918 util/evsel.c: No such file or directory.
> in util/evsel.c
> Missing separate debuginfos, use: debuginfo-install audit-libs-2.3.7-1.0.1.el6.sparc64 bzip2-libs-1.0.5-7.el6_0.sparc64 elfutils-libelf-0.155-2.0.3.el6.sparc64 elfutils-libs-0.155-2.0.3.el6.sparc64 glibc-2.12-1.132.0.8.el6_5.sparc64 numactl-2.0.7-8.el6.sparc64 python-libs-2.6.6-52.0.2.el6.sparc64 slang-2.2.1-1.el6.sparc64 xz-libs-4.999.9-0.3.beta.20091007git.el6.sparc64 zlib-1.2.3-29.el6.sparc64
> (gdb) bt
> 0 0x0000000000173d7c in perf_evsel__intval (evsel=<value optimized out>, sample=0x7feffffda28,
> name=0x289b28 "prev_state") at util/evsel.c:1918
> 1 0x0000000000123b94 in process_sample_sched_switch (tchart=0x7feffffe040, evsel=0x4ca850, sample=0x7feffffda28,
> backtrace=0xc39010 "") at builtin-timechart.c:627
> 2 0x0000000000122828 in process_sample_event (tool=0x7feffffe040, event=<value optimized out>, sample=0x7feffffda28,
> evsel=0x4ca850, machine=0x4c9c88) at builtin-timechart.c:569
>
> Another extended load on unaligned pointer. As before fix by copying to
Humm, so this is being put that way by the tracepoint in the kernel?
Lemme see...
It is this one, right?
[root@ssdandy ~]# cat /t/events/sched/sched_switch/format
name: sched_switch
ID: 228
format:
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:char prev_comm[16]; offset:8; size:16; signed:1;
field:pid_t prev_pid; offset:24; size:4; signed:1;
field:int prev_prio; offset:28; size:4; signed:1;
field:long prev_state; offset:32; size:8; signed:1;
field:char next_comm[16]; offset:40; size:16; signed:1;
field:pid_t next_pid; offset:56; size:4; signed:1;
field:int next_prio; offset:60; size:4; signed:1;
print fmt: "prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d", REC->prev_comm, REC->prev_pid, REC->prev_prio, REC->prev_state & (1024-1) ? __print_flags(REC->prev_state & (1024-1), "|", { 1, "S"} , { 2, "D" }, { 4, "T" }, { 8, "t" }, { 16, "Z" }, { 32, "X" }, { 64, "x" }, { 128, "K" }, { 256, "W" }, { 512, "P" }) : "R", REC->prev_state & 1024 ? "+" : "", REC->next_comm, REC->next_pid, REC->next_prio
[root@ssdandy ~]#
---------------------------------------------
I.e. this should be reading from the ring buffer, where this info was put, all aligned, by the kernel,
except when we need to use struct perf_mmap->event_copy, that is...
struct perf_mmap {
void *base;
int mask;
int refcnt;
unsigned int prev;
char event_copy[PERF_SAMPLE_MAX_SIZE] __attribute__((aligned(8)));
};
sizeof(u64) aligned, no?
/me scratches head, should be missing something embarassingly simple :-/
- Arnaldo
> a temporary variable using memcpy.
>
> Signed-off-by: David Ahern <david.ahern@oracle.com>
> ---
> tools/perf/util/evsel.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index daa053d..ef20371 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -1925,7 +1925,7 @@ u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
> value = *(u32 *)ptr;
> break;
> case 8:
> - value = *(u64 *)ptr;
> + memcpy(&value, ptr, sizeof(u64));
> break;
> default:
> return 0;
> --
> 1.7.1
^ permalink raw reply [flat|nested] 4+ messages in thread* [tip:perf/core] perf timechart: Fix SIBGUS error on sparc64
2015-03-24 20:14 [PATCH] perf timechart: Fix SIBGUS error on sparc64 David Ahern
2015-03-24 21:15 ` Arnaldo Carvalho de Melo
@ 2015-03-27 7:39 ` tip-bot for David Ahern
1 sibling, 0 replies; 4+ messages in thread
From: tip-bot for David Ahern @ 2015-03-27 7:39 UTC (permalink / raw)
To: linux-tip-commits; +Cc: mingo, tglx, linux-kernel, hpa, acme, david.ahern
Commit-ID: e94eedab3ab8201fd41480171b2fabbf3c5b1ae0
Gitweb: http://git.kernel.org/tip/e94eedab3ab8201fd41480171b2fabbf3c5b1ae0
Author: David Ahern <david.ahern@oracle.com>
AuthorDate: Tue, 24 Mar 2015 16:14:09 -0400
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Thu, 26 Mar 2015 10:52:28 -0300
perf timechart: Fix SIBGUS error on sparc64
perf timechart -T on sparc64 is terminating due to SIGBUS. Backtrace:
Program received signal SIGBUS, Bus error.
0x0000000000173d7c in perf_evsel__intval (evsel=<value optimized out>, sample=0x7feffffda28, name=0x289b28 "prev_state")
at util/evsel.c:1918
1918 util/evsel.c: No such file or directory.
in util/evsel.c
Missing separate debuginfos, use: debuginfo-install audit-libs-2.3.7-1.0.1.el6.sparc64 bzip2-libs-1.0.5-7.el6_0.sparc64 elfutils-libelf-0.155-2.0.3.el6.sparc64 elfutils-libs-0.155-2.0.3.el6.sparc64 glibc-2.12-1.132.0.8.el6_5.sparc64 numactl-2.0.7-8.el6.sparc64 python-libs-2.6.6-52.0.2.el6.sparc64 slang-2.2.1-1.el6.sparc64 xz-libs-4.999.9-0.3.beta.20091007git.el6.sparc64 zlib-1.2.3-29.el6.sparc64
(gdb) bt
0 0x0000000000173d7c in perf_evsel__intval (evsel=<value optimized out>, sample=0x7feffffda28,
name=0x289b28 "prev_state") at util/evsel.c:1918
1 0x0000000000123b94 in process_sample_sched_switch (tchart=0x7feffffe040, evsel=0x4ca850, sample=0x7feffffda28,
backtrace=0xc39010 "") at builtin-timechart.c:627
2 0x0000000000122828 in process_sample_event (tool=0x7feffffe040, event=<value optimized out>, sample=0x7feffffda28,
evsel=0x4ca850, machine=0x4c9c88) at builtin-timechart.c:569
Another extended load on unaligned pointer. As before fix by copying to
a temporary variable using memcpy.
Signed-off-by: David Ahern <david.ahern@oracle.com>
Link: http://lkml.kernel.org/r/1427228049-51893-1-git-send-email-david.ahern@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/evsel.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index bb4eff2..358e595 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1915,7 +1915,7 @@ u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
value = *(u32 *)ptr;
break;
case 8:
- value = *(u64 *)ptr;
+ memcpy(&value, ptr, sizeof(u64));
break;
default:
return 0;
^ permalink raw reply related [flat|nested] 4+ messages in thread