alistair23-linux/tools/perf/util/ordered-events.h
Jiri Olsa d5ceb62b36 perf ordered_events: Add 'struct ordered_events_buffer' layer
When ordering events, we use preallocated buffers to store separate
events.  Those buffers currently don't have their own struct, but since
they are basically an array of 'struct ordered_event' objects, we use
the first event to hold buffers data - list head, that holds all buffers
together:

   struct ordered_events {
     ...
     struct ordered_event *buffer;
     ...
   };

   struct ordered_event {
     u64               timestamp;
     u64               file_offset;
     union perf_event  *event;
     struct list_head  list;
   };

This is quite convoluted and error prone as demonstrated by free-ing
issue discovered and fixed by Stephane in here [1].

This patch adds the 'struct ordered_events_buffer' object, that holds
the buffer data and frees it up properly.

[1] - https://marc.info/?l=linux-kernel&m=153376761329335&w=2

Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Stephane Eranian <eranian@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180907102455.7030-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-09-19 10:24:57 -03:00

72 lines
1.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ORDERED_EVENTS_H
#define __ORDERED_EVENTS_H
#include <linux/types.h>
struct perf_sample;
struct ordered_event {
u64 timestamp;
u64 file_offset;
union perf_event *event;
struct list_head list;
};
enum oe_flush {
OE_FLUSH__NONE,
OE_FLUSH__FINAL,
OE_FLUSH__ROUND,
OE_FLUSH__HALF,
};
struct ordered_events;
typedef int (*ordered_events__deliver_t)(struct ordered_events *oe,
struct ordered_event *event);
struct ordered_events_buffer {
struct list_head list;
struct ordered_event event[0];
};
struct ordered_events {
u64 last_flush;
u64 next_flush;
u64 max_timestamp;
u64 max_alloc_size;
u64 cur_alloc_size;
struct list_head events;
struct list_head cache;
struct list_head to_free;
struct ordered_events_buffer *buffer;
struct ordered_event *last;
ordered_events__deliver_t deliver;
int buffer_idx;
unsigned int nr_events;
enum oe_flush last_flush_type;
u32 nr_unordered_events;
bool copy_on_queue;
};
int ordered_events__queue(struct ordered_events *oe, union perf_event *event,
u64 timestamp, u64 file_offset);
void ordered_events__delete(struct ordered_events *oe, struct ordered_event *event);
int ordered_events__flush(struct ordered_events *oe, enum oe_flush how);
void ordered_events__init(struct ordered_events *oe, ordered_events__deliver_t deliver);
void ordered_events__free(struct ordered_events *oe);
void ordered_events__reinit(struct ordered_events *oe);
static inline
void ordered_events__set_alloc_size(struct ordered_events *oe, u64 size)
{
oe->max_alloc_size = size;
}
static inline
void ordered_events__set_copy_on_queue(struct ordered_events *oe, bool copy)
{
oe->copy_on_queue = copy;
}
#endif /* __ORDERED_EVENTS_H */