linux/tools/perf/util/affinity.h

// SPDX-License-Identifier: GPL-2.0
#ifndef PERF_AFFINITY_H
#define PERF_AFFINITY_H 1

#include <stdbool.h>

struct perf_cpu_map;
struct affinity {
	unsigned long *orig_cpus;
	unsigned long *sched_cpus;
	bool changed;
};

void affinity__cleanup(struct affinity *a);
void affinity__set(struct affinity *a, int cpu);
int affinity__setup(struct affinity *a);
void cpu_map__set_affinity(const struct perf_cpu_map *cpumap);

#endif // PERF_AFFINITY_H
perf affinity: Add infrastructure to save/restore affinity The kernel perf subsystem has to IPI to the target CPU for many operations. On systems with many CPUs and when managing many events the overhead can be dominated by lots of IPIs. An alternative is to set up CPU affinity in the perf tool, then set up all the events for that CPU, and then move on to the next CPU. Add some affinity management infrastructure to enable such a model. Used in followon patches. Committer notes: Use zfree() in some places, add missing stdbool.h header, some minor coding style changes. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lore.kernel.org/lkml/20191121001522.180827-3-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> 2019-11-20 16:15:12 -08:00			`// SPDX-License-Identifier: GPL-2.0`
			`#ifndef PERF_AFFINITY_H`
			`#define PERF_AFFINITY_H 1`

			`#include <stdbool.h>`

perf test: Expand user space event reading (rdpmc) tests Test that disabling rdpmc support via /sys/bus/event_source/cpu*/rdpmc disables reading in the mmap (libperf read support will fallback to using a system call). Test all hybrid PMUs support rdpmc. Ensure hybrid PMUs use the correct CPU to rdpmc the correct event. Previously the test would open cycles or instructions with no extended type then rdpmc it on whatever CPU. This could fail/skip due to which CPU the test was scheduled upon. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20250614004528.1652860-1-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> 2025-06-13 17:45:28 -07:00			`struct perf_cpu_map;`
perf affinity: Add infrastructure to save/restore affinity The kernel perf subsystem has to IPI to the target CPU for many operations. On systems with many CPUs and when managing many events the overhead can be dominated by lots of IPIs. An alternative is to set up CPU affinity in the perf tool, then set up all the events for that CPU, and then move on to the next CPU. Add some affinity management infrastructure to enable such a model. Used in followon patches. Committer notes: Use zfree() in some places, add missing stdbool.h header, some minor coding style changes. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lore.kernel.org/lkml/20191121001522.180827-3-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> 2019-11-20 16:15:12 -08:00			`struct affinity {`
			`unsigned long *orig_cpus;`
			`unsigned long *sched_cpus;`
			`bool changed;`
			`};`

			`void affinity__cleanup(struct affinity *a);`
			`void affinity__set(struct affinity *a, int cpu);`
			`int affinity__setup(struct affinity *a);`
perf test: Expand user space event reading (rdpmc) tests Test that disabling rdpmc support via /sys/bus/event_source/cpu*/rdpmc disables reading in the mmap (libperf read support will fallback to using a system call). Test all hybrid PMUs support rdpmc. Ensure hybrid PMUs use the correct CPU to rdpmc the correct event. Previously the test would open cycles or instructions with no extended type then rdpmc it on whatever CPU. This could fail/skip due to which CPU the test was scheduled upon. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20250614004528.1652860-1-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> 2025-06-13 17:45:28 -07:00			`void cpu_map__set_affinity(const struct perf_cpu_map *cpumap);`
perf affinity: Add infrastructure to save/restore affinity The kernel perf subsystem has to IPI to the target CPU for many operations. On systems with many CPUs and when managing many events the overhead can be dominated by lots of IPIs. An alternative is to set up CPU affinity in the perf tool, then set up all the events for that CPU, and then move on to the next CPU. Add some affinity management infrastructure to enable such a model. Used in followon patches. Committer notes: Use zfree() in some places, add missing stdbool.h header, some minor coding style changes. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lore.kernel.org/lkml/20191121001522.180827-3-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> 2019-11-20 16:15:12 -08:00
			`#endif // PERF_AFFINITY_H`