linux/tools/bpf/runqslower/runqslower.bpf.c
SanjayKumar Jeyakumar 5616e895ec tools/runqslower: Use __state instead of state
Commit 2f064a59a1 ("sched: Change task_struct::state") renamed task->state
to task->__state in task_struct. Fix runqslower to use the new name of the
field.

Fixes: 2f064a59a1 ("sched: Change task_struct::state")
Signed-off-by: SanjayKumar Jeyakumar <vjsanjay@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210707052914.21473-1-vjsanjay@gmail.com
2021-07-07 09:42:26 -07:00

108 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include "runqslower.h"
#define TASK_RUNNING 0
#define BPF_F_CURRENT_CPU 0xffffffffULL
const volatile __u64 min_us = 0;
const volatile pid_t targ_pid = 0;
struct {
__uint(type, BPF_MAP_TYPE_TASK_STORAGE);
__uint(map_flags, BPF_F_NO_PREALLOC);
__type(key, int);
__type(value, u64);
} start SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(u32));
__uint(value_size, sizeof(u32));
} events SEC(".maps");
/* record enqueue timestamp */
__always_inline
static int trace_enqueue(struct task_struct *t)
{
u32 pid = t->pid;
u64 *ptr;
if (!pid || (targ_pid && targ_pid != pid))
return 0;
ptr = bpf_task_storage_get(&start, t, 0,
BPF_LOCAL_STORAGE_GET_F_CREATE);
if (!ptr)
return 0;
*ptr = bpf_ktime_get_ns();
return 0;
}
SEC("tp_btf/sched_wakeup")
int handle__sched_wakeup(u64 *ctx)
{
/* TP_PROTO(struct task_struct *p) */
struct task_struct *p = (void *)ctx[0];
return trace_enqueue(p);
}
SEC("tp_btf/sched_wakeup_new")
int handle__sched_wakeup_new(u64 *ctx)
{
/* TP_PROTO(struct task_struct *p) */
struct task_struct *p = (void *)ctx[0];
return trace_enqueue(p);
}
SEC("tp_btf/sched_switch")
int handle__sched_switch(u64 *ctx)
{
/* TP_PROTO(bool preempt, struct task_struct *prev,
* struct task_struct *next)
*/
struct task_struct *prev = (struct task_struct *)ctx[1];
struct task_struct *next = (struct task_struct *)ctx[2];
struct event event = {};
u64 *tsp, delta_us;
long state;
u32 pid;
/* ivcsw: treat like an enqueue event and store timestamp */
if (prev->__state == TASK_RUNNING)
trace_enqueue(prev);
pid = next->pid;
/* For pid mismatch, save a bpf_task_storage_get */
if (!pid || (targ_pid && targ_pid != pid))
return 0;
/* fetch timestamp and calculate delta */
tsp = bpf_task_storage_get(&start, next, 0, 0);
if (!tsp)
return 0; /* missed enqueue */
delta_us = (bpf_ktime_get_ns() - *tsp) / 1000;
if (min_us && delta_us <= min_us)
return 0;
event.pid = pid;
event.delta_us = delta_us;
bpf_get_current_comm(&event.task, sizeof(event.task));
/* output */
bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU,
&event, sizeof(event));
bpf_task_storage_delete(&start, next);
return 0;
}
char LICENSE[] SEC("license") = "GPL";