linux/tools/perf/util/mmap.h
Alexey Budankov 8384a2600c perf record: Adapt affinity to machines with #CPUs > 1K
Use struct mmap_cpu_mask type for the tool's thread and mmap data
buffers to overcome current 1024 CPUs mask size limitation of cpu_set_t
type.

Currently glibc's cpu_set_t type has an internal mask size limit of 1024
CPUs.

Moving to the 'struct mmap_cpu_mask' type allows overcoming that limit.

The tools bitmap API is used to manipulate objects of 'struct mmap_cpu_mask'
type.

Committer notes:

To print the 'nbits' struct member we must use %zd, since it is a
size_t, this fixes the build in some toolchains/arches.

Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/96d7e2ff-ce8b-c1e0-d52c-aa59ea96f0ea@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-01-06 11:46:09 -03:00

67 lines
1.5 KiB
C

#ifndef __PERF_MMAP_H
#define __PERF_MMAP_H 1
#include <internal/mmap.h>
#include <linux/compiler.h>
#include <linux/refcount.h>
#include <linux/types.h>
#include <linux/ring_buffer.h>
#include <stdbool.h>
#include <pthread.h> // for cpu_set_t
#ifdef HAVE_AIO_SUPPORT
#include <aio.h>
#endif
#include "auxtrace.h"
#include "event.h"
struct aiocb;
struct mmap_cpu_mask {
unsigned long *bits;
size_t nbits;
};
#define MMAP_CPU_MASK_BYTES(m) \
(BITS_TO_LONGS(((struct mmap_cpu_mask *)m)->nbits) * sizeof(unsigned long))
/**
* struct mmap - perf's ring buffer mmap details
*
* @refcnt - e.g. code using PERF_EVENT_IOC_SET_OUTPUT to share this
*/
struct mmap {
struct perf_mmap core;
struct auxtrace_mmap auxtrace_mmap;
#ifdef HAVE_AIO_SUPPORT
struct {
void **data;
struct aiocb *cblocks;
struct aiocb **aiocb;
int nr_cblocks;
} aio;
#endif
struct mmap_cpu_mask affinity_mask;
void *data;
int comp_level;
};
struct mmap_params {
struct perf_mmap_param core;
int nr_cblocks, affinity, flush, comp_level;
struct auxtrace_mmap_params auxtrace_mp;
};
int mmap__mmap(struct mmap *map, struct mmap_params *mp, int fd, int cpu);
void mmap__munmap(struct mmap *map);
union perf_event *perf_mmap__read_forward(struct mmap *map);
int perf_mmap__push(struct mmap *md, void *to,
int push(struct mmap *map, void *to, void *buf, size_t size));
size_t mmap__mmap_len(struct mmap *map);
void mmap_cpu_mask__scnprintf(struct mmap_cpu_mask *mask, const char *tag);
#endif /*__PERF_MMAP_H */