2 * Copyright (c) 2022 Arm and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 #include <vnet/vnet.h>
18 #include <vlibapi/api.h>
19 #include <vlibmemory/api.h>
20 #include <vnet/plugin/plugin.h>
21 #include <vpp/app/version.h>
22 #include <linux/limits.h>
23 #include <sys/ioctl.h>
25 #include <perfmon/perfmon.h>
27 #define barrier() asm volatile("dmb ish" : : : "memory");
31 static_always_inline u64
32 get_pmc_register (u32 pmc_idx)
36 /* i.e. CPU Cycle event code 0x11 - need to read via pmccntr_el0 */
37 asm volatile("mrs %x0, pmccntr_el0" : "=r"(value));
40 /* set event register 0x0-0x1F */
41 asm volatile("msr pmselr_el0, %x0" : : "r"((pmc_idx)));
42 /* get register value */
43 asm volatile("mrs %x0, pmxevcntr_el0" : "=r"(value));
45 asm volatile("isb" : : : "memory");
49 static_always_inline u64
50 read_pmc_from_mmap (struct perf_event_mmap_page *pc)
62 if (pc->cap_user_rdpmc && idx)
64 width = pc->pmc_width;
65 pmc = get_pmc_register (idx - 1);
66 /* for 32 bit regs, left shift 32b to zero/discard the top bits */
72 while (pc->lock != seq);
77 static_always_inline void
78 perfmon_read_pmcs (u64 *counters, perfmon_thread_runtime_t *rt, u8 n_counters)
84 counters[6] = read_pmc_from_mmap (rt->mmap_pages[6]);
86 counters[5] = read_pmc_from_mmap (rt->mmap_pages[5]);
88 counters[4] = read_pmc_from_mmap (rt->mmap_pages[4]);
90 counters[3] = read_pmc_from_mmap (rt->mmap_pages[3]);
92 counters[2] = read_pmc_from_mmap (rt->mmap_pages[2]);
94 counters[1] = read_pmc_from_mmap (rt->mmap_pages[1]);
96 counters[0] = read_pmc_from_mmap (rt->mmap_pages[0]);
102 perfmon_dispatch_wrapper (vlib_main_t *vm, vlib_node_runtime_t *node,
105 perfmon_main_t *pm = &perfmon_main;
106 perfmon_thread_runtime_t *rt =
107 vec_elt_at_index (pm->thread_runtimes, vm->thread_index);
108 perfmon_node_stats_t *s =
109 vec_elt_at_index (rt->node_stats, node->node_index);
110 u8 n_events = rt->n_events;
111 u64 before[n_events];
116 clib_prefetch_load (s);
118 perfmon_read_pmcs (before, rt, n_events);
119 rv = node->function (vm, node, frame);
120 perfmon_read_pmcs (after, rt, n_events);
128 for (int i = 0; i < n_events; i++)
130 s->value[i] += after[i] - before[i];
137 arm_config_dispatch_wrapper (perfmon_bundle_t *b,
138 vlib_node_function_t **dispatch_wrapper)
140 (*dispatch_wrapper) = perfmon_dispatch_wrapper;