huatuo/bpf/memory_cgroup.c

56 lines
1.4 KiB
C

#include "bpf_common.h"
#include "vmlinux.h"
#include "vmlinux_sched.h"
#include <bpf/bpf_core_read.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
char __license[] SEC("license") = "Dual MIT/GPL";
struct mem_cgroup_metric {
/* cg: direct reclaim count caused by try_charge */
unsigned long directstall_count;
};
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__type(key, unsigned long);
__type(value, struct mem_cgroup_metric);
__uint(max_entries, 10240);
} mem_cgroup_map SEC(".maps");
SEC("tracepoint/vmscan/mm_vmscan_memcg_reclaim_begin")
int tracepoint_vmscan_mm_vmscan_memcg_reclaim_begin(struct pt_regs *ctx)
{
struct cgroup_subsys_state *mm_subsys;
struct mem_cgroup_metric *valp;
struct task_struct *task;
task = (struct task_struct *)bpf_get_current_task();
if (BPF_CORE_READ(task, flags) & PF_KSWAPD)
return 0;
mm_subsys = BPF_CORE_READ(task, cgroups, subsys[memory_cgrp_id]);
valp = bpf_map_lookup_elem(&mem_cgroup_map, &mm_subsys);
if (!valp) {
struct mem_cgroup_metric new_metrics = {
.directstall_count = 1,
};
bpf_map_update_elem(&mem_cgroup_map, &mm_subsys, &new_metrics,
BPF_ANY);
return 0;
}
__sync_fetch_and_add(&valp->directstall_count, 1);
return 0;
}
SEC("kprobe/mem_cgroup_css_released")
int kprobe_mem_cgroup_css_released(struct pt_regs *ctx)
{
u64 css = PT_REGS_PARM1(ctx);
bpf_map_delete_elem(&mem_cgroup_map, &css);
return 0;
}