linux/tools/perf/util/event.h
Arnaldo Carvalho de Melo 56b03f3c4d perf tools: Handle relocatable kernels
DSOs don't have this problem because the kernel emits a
PERF_MMAP for each new executable mapping it performs on
monitored threads.

To fix the kernel case we simulate the same behaviour, by having
'perf record' to synthesize a PERF_MMAP for the kernel, encoded
like this:

[root@doppio ~]# perf record -a -f sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.344 MB perf.data (~15038 samples) ]
[root@doppio ~]# perf report -D | head -10

0xd0 [0x40]: event: 1
.
. ... raw event: size 64 bytes
.  0000:  01 00 00 00 00 00 40 00 00 00 00 00 00 00 00 00 ......@........
.  0010:  00 00 00 81 ff ff ff ff 00 00 00 00 00 00 00 00 ...............
.  0020:  00 00 00 00 00 00 00 00 5b 6b 65 72 6e 65 6c 2e ........  [kernel
.  0030:  6b 61 6c 6c 73 79 6d 73 2e 5f 74 65 78 74 5d 00  kallsyms._text]
.  0xd0
[0x40]: PERF_RECORD_MMAP 0/0: [0xffffffff81000000((nil)) @ (nil)]: [kernel.kallsyms._text]

I.e. we identify such event as having:

 .pid      = 0
 .filename = [kernel.kallsyms.REFNAME]
 .start    = REFNAME addr in /proc/kallsyms at 'perf record' time

and use now a hardcoded value of '.text' for REFNAME.

Then, later, in 'perf report', if there are any kernel hits and
thus we need to resolve kernel symbols, we search for REFNAME
and if its address changed, relocation happened and we thus must
change the kernel mapping routines to one that uses .pgoff as
the relocation to apply.

This way we use the same mechanism used for the other DSOs and
don't have to do a two pass in all the kernel symbols.

Reported-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
LKML-Reference: <1262717431-1246-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 10:09:11 +01:00

129 lines
2.6 KiB
C

#ifndef __PERF_RECORD_H
#define __PERF_RECORD_H
#include <limits.h>
#include "../perf.h"
#include "map.h"
/*
* PERF_SAMPLE_IP | PERF_SAMPLE_TID | *
*/
struct ip_event {
struct perf_event_header header;
u64 ip;
u32 pid, tid;
unsigned char __more_data[];
};
struct mmap_event {
struct perf_event_header header;
u32 pid, tid;
u64 start;
u64 len;
u64 pgoff;
char filename[PATH_MAX];
};
struct comm_event {
struct perf_event_header header;
u32 pid, tid;
char comm[16];
};
struct fork_event {
struct perf_event_header header;
u32 pid, ppid;
u32 tid, ptid;
u64 time;
};
struct lost_event {
struct perf_event_header header;
u64 id;
u64 lost;
};
/*
* PERF_FORMAT_ENABLED | PERF_FORMAT_RUNNING | PERF_FORMAT_ID
*/
struct read_event {
struct perf_event_header header;
u32 pid, tid;
u64 value;
u64 time_enabled;
u64 time_running;
u64 id;
};
struct sample_event {
struct perf_event_header header;
u64 array[];
};
struct sample_data {
u64 ip;
u32 pid, tid;
u64 time;
u64 addr;
u64 id;
u64 stream_id;
u32 cpu;
u64 period;
struct ip_callchain *callchain;
u32 raw_size;
void *raw_data;
};
#define BUILD_ID_SIZE 20
struct build_id_event {
struct perf_event_header header;
u8 build_id[ALIGN(BUILD_ID_SIZE, sizeof(u64))];
char filename[];
};
typedef union event_union {
struct perf_event_header header;
struct ip_event ip;
struct mmap_event mmap;
struct comm_event comm;
struct fork_event fork;
struct lost_event lost;
struct read_event read;
struct sample_event sample;
} event_t;
struct events_stats {
u64 total;
u64 lost;
};
void event__print_totals(void);
struct perf_session;
int event__synthesize_thread(pid_t pid,
int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session);
void event__synthesize_threads(int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session);
int event__synthesize_kernel_mmap(int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session,
const char *symbol_name);
int event__process_comm(event_t *self, struct perf_session *session);
int event__process_lost(event_t *self, struct perf_session *session);
int event__process_mmap(event_t *self, struct perf_session *session);
int event__process_task(event_t *self, struct perf_session *session);
struct addr_location;
int event__preprocess_sample(const event_t *self, struct perf_session *session,
struct addr_location *al, symbol_filter_t filter);
int event__parse_sample(event_t *event, u64 type, struct sample_data *data);
#endif /* __PERF_RECORD_H */