alistair23-linux/samples/bpf/cpustat_kern.c
Toke Høiland-Jørgensen 7cf245a37e samples/bpf: Use consistent include paths for libbpf
Fix all files in samples/bpf to include libbpf header files with the bpf/
prefix, to be consistent with external users of the library. Also ensure
that all includes of exported libbpf header files (those that are exported
on 'make install' of the library) use bracketed includes instead of quoted.

To make sure no new files are introduced that doesn't include the bpf/
prefix in its include, remove tools/lib/bpf from the include path entirely,
and use tools/lib instead.

Fixes: 6910d7d386 ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560911.1683545.8795966751309534150.stgit@toke.dk
2020-01-20 16:37:45 -08:00

282 lines
7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/version.h>
#include <linux/ptrace.h>
#include <uapi/linux/bpf.h>
#include <bpf/bpf_helpers.h>
/*
* The CPU number, cstate number and pstate number are based
* on 96boards Hikey with octa CA53 CPUs.
*
* Every CPU have three idle states for cstate:
* WFI, CPU_OFF, CLUSTER_OFF
*
* Every CPU have 5 operating points:
* 208MHz, 432MHz, 729MHz, 960MHz, 1200MHz
*
* This code is based on these assumption and other platforms
* need to adjust these definitions.
*/
#define MAX_CPU 8
#define MAX_PSTATE_ENTRIES 5
#define MAX_CSTATE_ENTRIES 3
static int cpu_opps[] = { 208000, 432000, 729000, 960000, 1200000 };
/*
* my_map structure is used to record cstate and pstate index and
* timestamp (Idx, Ts), when new event incoming we need to update
* combination for new state index and timestamp (Idx`, Ts`).
*
* Based on (Idx, Ts) and (Idx`, Ts`) we can calculate the time
* interval for the previous state: Duration(Idx) = Ts` - Ts.
*
* Every CPU has one below array for recording state index and
* timestamp, and record for cstate and pstate saperately:
*
* +--------------------------+
* | cstate timestamp |
* +--------------------------+
* | cstate index |
* +--------------------------+
* | pstate timestamp |
* +--------------------------+
* | pstate index |
* +--------------------------+
*/
#define MAP_OFF_CSTATE_TIME 0
#define MAP_OFF_CSTATE_IDX 1
#define MAP_OFF_PSTATE_TIME 2
#define MAP_OFF_PSTATE_IDX 3
#define MAP_OFF_NUM 4
struct bpf_map_def SEC("maps") my_map = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(u64),
.max_entries = MAX_CPU * MAP_OFF_NUM,
};
/* cstate_duration records duration time for every idle state per CPU */
struct bpf_map_def SEC("maps") cstate_duration = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(u64),
.max_entries = MAX_CPU * MAX_CSTATE_ENTRIES,
};
/* pstate_duration records duration time for every operating point per CPU */
struct bpf_map_def SEC("maps") pstate_duration = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(u64),
.max_entries = MAX_CPU * MAX_PSTATE_ENTRIES,
};
/*
* The trace events for cpu_idle and cpu_frequency are taken from:
* /sys/kernel/debug/tracing/events/power/cpu_idle/format
* /sys/kernel/debug/tracing/events/power/cpu_frequency/format
*
* These two events have same format, so define one common structure.
*/
struct cpu_args {
u64 pad;
u32 state;
u32 cpu_id;
};
/* calculate pstate index, returns MAX_PSTATE_ENTRIES for failure */
static u32 find_cpu_pstate_idx(u32 frequency)
{
u32 i;
for (i = 0; i < sizeof(cpu_opps) / sizeof(u32); i++) {
if (frequency == cpu_opps[i])
return i;
}
return i;
}
SEC("tracepoint/power/cpu_idle")
int bpf_prog1(struct cpu_args *ctx)
{
u64 *cts, *pts, *cstate, *pstate, prev_state, cur_ts, delta;
u32 key, cpu, pstate_idx;
u64 *val;
if (ctx->cpu_id > MAX_CPU)
return 0;
cpu = ctx->cpu_id;
key = cpu * MAP_OFF_NUM + MAP_OFF_CSTATE_TIME;
cts = bpf_map_lookup_elem(&my_map, &key);
if (!cts)
return 0;
key = cpu * MAP_OFF_NUM + MAP_OFF_CSTATE_IDX;
cstate = bpf_map_lookup_elem(&my_map, &key);
if (!cstate)
return 0;
key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_TIME;
pts = bpf_map_lookup_elem(&my_map, &key);
if (!pts)
return 0;
key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_IDX;
pstate = bpf_map_lookup_elem(&my_map, &key);
if (!pstate)
return 0;
prev_state = *cstate;
*cstate = ctx->state;
if (!*cts) {
*cts = bpf_ktime_get_ns();
return 0;
}
cur_ts = bpf_ktime_get_ns();
delta = cur_ts - *cts;
*cts = cur_ts;
/*
* When state doesn't equal to (u32)-1, the cpu will enter
* one idle state; for this case we need to record interval
* for the pstate.
*
* OPP2
* +---------------------+
* OPP1 | |
* ---------+ |
* | Idle state
* +---------------
*
* |<- pstate duration ->|
* ^ ^
* pts cur_ts
*/
if (ctx->state != (u32)-1) {
/* record pstate after have first cpu_frequency event */
if (!*pts)
return 0;
delta = cur_ts - *pts;
pstate_idx = find_cpu_pstate_idx(*pstate);
if (pstate_idx >= MAX_PSTATE_ENTRIES)
return 0;
key = cpu * MAX_PSTATE_ENTRIES + pstate_idx;
val = bpf_map_lookup_elem(&pstate_duration, &key);
if (val)
__sync_fetch_and_add((long *)val, delta);
/*
* When state equal to (u32)-1, the cpu just exits from one
* specific idle state; for this case we need to record
* interval for the pstate.
*
* OPP2
* -----------+
* | OPP1
* | +-----------
* | Idle state |
* +---------------------+
*
* |<- cstate duration ->|
* ^ ^
* cts cur_ts
*/
} else {
key = cpu * MAX_CSTATE_ENTRIES + prev_state;
val = bpf_map_lookup_elem(&cstate_duration, &key);
if (val)
__sync_fetch_and_add((long *)val, delta);
}
/* Update timestamp for pstate as new start time */
if (*pts)
*pts = cur_ts;
return 0;
}
SEC("tracepoint/power/cpu_frequency")
int bpf_prog2(struct cpu_args *ctx)
{
u64 *pts, *cstate, *pstate, prev_state, cur_ts, delta;
u32 key, cpu, pstate_idx;
u64 *val;
cpu = ctx->cpu_id;
key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_TIME;
pts = bpf_map_lookup_elem(&my_map, &key);
if (!pts)
return 0;
key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_IDX;
pstate = bpf_map_lookup_elem(&my_map, &key);
if (!pstate)
return 0;
key = cpu * MAP_OFF_NUM + MAP_OFF_CSTATE_IDX;
cstate = bpf_map_lookup_elem(&my_map, &key);
if (!cstate)
return 0;
prev_state = *pstate;
*pstate = ctx->state;
if (!*pts) {
*pts = bpf_ktime_get_ns();
return 0;
}
cur_ts = bpf_ktime_get_ns();
delta = cur_ts - *pts;
*pts = cur_ts;
/* When CPU is in idle, bail out to skip pstate statistics */
if (*cstate != (u32)(-1))
return 0;
/*
* The cpu changes to another different OPP (in below diagram
* change frequency from OPP3 to OPP1), need recording interval
* for previous frequency OPP3 and update timestamp as start
* time for new frequency OPP1.
*
* OPP3
* +---------------------+
* OPP2 | |
* ---------+ |
* | OPP1
* +---------------
*
* |<- pstate duration ->|
* ^ ^
* pts cur_ts
*/
pstate_idx = find_cpu_pstate_idx(*pstate);
if (pstate_idx >= MAX_PSTATE_ENTRIES)
return 0;
key = cpu * MAX_PSTATE_ENTRIES + pstate_idx;
val = bpf_map_lookup_elem(&pstate_duration, &key);
if (val)
__sync_fetch_and_add((long *)val, delta);
return 0;
}
char _license[] SEC("license") = "GPL";
u32 _version SEC("version") = LINUX_VERSION_CODE;