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perf tools: Fix endian conversion reading event attr from file header

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The perf_event_attr struct has two __u32's at the top and
they need to be swapped individually.

With this change I was able to analyze a perf.data collected in a
32-bit PPC VM on an x86 system. I tested both 32-bit and 64-bit
binaries for the Intel analysis side; both read the PPC perf.data
file correctly.

-v2:
 - changed the existing perf_event__attr_swap() to swap only elements
   of perf_event_attr and exported it for use in swapping the
   attributes in the file header
 - updated swap_ops used for processing events

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: acme@ghostprotocols.net
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1310754849-12474-1-git-send-email-dsahern@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
David Ahern 2011-07-15 12:34:09 -06:00 committed by Ingo Molnar
parent 0111919da2
commit eda3913bb7
3 changed files with 23 additions and 13 deletions
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5
tools/perf/util/header.c
View File

@ -877,9 +877,12 @@ int perf_session__read_header(struct perf_session *session, int fd)
struct perf_evsel *evsel;
off_t tmp;
if (perf_header__getbuffer64(header, fd, &f_attr, sizeof(f_attr)))
if (readn(fd, &f_attr, sizeof(f_attr)) <= 0)
goto out_errno;
if (header->needs_swap)
perf_event__attr_swap(&f_attr.attr);
tmp = lseek(fd, 0, SEEK_CUR);
evsel = perf_evsel__new(&f_attr.attr, i);

30
tools/perf/util/session.c
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@ -413,20 +413,26 @@ static void perf_event__read_swap(union perf_event *event)
event->read.id = bswap_64(event->read.id);
}
static void perf_event__attr_swap(union perf_event *event)
/* exported for swapping attributes in file header */
void perf_event__attr_swap(struct perf_event_attr *attr)
{
attr->type = bswap_32(attr->type);
attr->size = bswap_32(attr->size);
attr->config = bswap_64(attr->config);
attr->sample_period = bswap_64(attr->sample_period);
attr->sample_type = bswap_64(attr->sample_type);
attr->read_format = bswap_64(attr->read_format);
attr->wakeup_events = bswap_32(attr->wakeup_events);
attr->bp_type = bswap_32(attr->bp_type);
attr->bp_addr = bswap_64(attr->bp_addr);
attr->bp_len = bswap_64(attr->bp_len);
}
static void perf_event__hdr_attr_swap(union perf_event *event)
{
size_t size;
event->attr.attr.type = bswap_32(event->attr.attr.type);
event->attr.attr.size = bswap_32(event->attr.attr.size);
event->attr.attr.config = bswap_64(event->attr.attr.config);
event->attr.attr.sample_period = bswap_64(event->attr.attr.sample_period);
event->attr.attr.sample_type = bswap_64(event->attr.attr.sample_type);
event->attr.attr.read_format = bswap_64(event->attr.attr.read_format);
event->attr.attr.wakeup_events = bswap_32(event->attr.attr.wakeup_events);
event->attr.attr.bp_type = bswap_32(event->attr.attr.bp_type);
event->attr.attr.bp_addr = bswap_64(event->attr.attr.bp_addr);
event->attr.attr.bp_len = bswap_64(event->attr.attr.bp_len);
perf_event__attr_swap(&event->attr.attr);
size = event->header.size;
size -= (void *)&event->attr.id - (void *)event;
@ -454,7 +460,7 @@ static perf_event__swap_op perf_event__swap_ops[] = {
[PERF_RECORD_LOST] = perf_event__all64_swap,
[PERF_RECORD_READ] = perf_event__read_swap,
[PERF_RECORD_SAMPLE] = perf_event__all64_swap,
[PERF_RECORD_HEADER_ATTR] = perf_event__attr_swap,
[PERF_RECORD_HEADER_ATTR] = perf_event__hdr_attr_swap,
[PERF_RECORD_HEADER_EVENT_TYPE] = perf_event__event_type_swap,
[PERF_RECORD_HEADER_TRACING_DATA] = perf_event__tracing_data_swap,
[PERF_RECORD_HEADER_BUILD_ID] = NULL,

1
tools/perf/util/session.h
View File

@ -112,6 +112,7 @@ int perf_session__set_kallsyms_ref_reloc_sym(struct map **maps,
u64 addr);
void mem_bswap_64(void *src, int byte_size);
void perf_event__attr_swap(struct perf_event_attr *attr);
int perf_session__create_kernel_maps(struct perf_session *self);