From 4d1792d0a2564caf1620a2cc9aa6f12284b3a56f Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Wed, 6 Sep 2023 10:49:01 -0700 Subject: perf lock contention: Add --lock-cgroup option The --lock-cgroup option shows lock contention stats break down by cgroups. Add LOCK_AGGR_CGROUP mode and use it instead of use_cgroup field. $ sudo ./perf lock con -ab --lock-cgroup sleep 1 contended total wait max wait avg wait cgroup 8 15.70 us 6.34 us 1.96 us / 2 1.48 us 747 ns 738 ns /user.slice/.../app.slice/app-gnome-google\x2dchrome-6442.scope 1 848 ns 848 ns 848 ns /user.slice/.../session.slice/org.gnome.Shell@x11.service 1 220 ns 220 ns 220 ns /user.slice/.../session.slice/pipewire-pulse.service For now, the cgroup mode only works with BPF (-b). Committer notes: Remove -g as it is used in the other tools with a clear meaning of collect/show callchains. As agreed with Namhyung off list. Reviewed-by: Ian Rogers Signed-off-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Hao Luo Cc: Ingo Molnar Cc: Jiri Olsa Cc: Peter Zijlstra Cc: Song Liu Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20230906174903.346486-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-lock.txt | 3 ++ tools/perf/builtin-lock.c | 40 +++++++++++++++++++++++++- tools/perf/util/bpf_lock_contention.c | 16 +++++++---- tools/perf/util/bpf_skel/lock_contention.bpf.c | 31 +++++++++++++++++++- tools/perf/util/bpf_skel/lock_data.h | 3 +- tools/perf/util/lock-contention.h | 1 - 6 files changed, 84 insertions(+), 10 deletions(-) diff --git a/tools/perf/Documentation/perf-lock.txt b/tools/perf/Documentation/perf-lock.txt index 30eea576721f..4b5cdf4b33c6 100644 --- a/tools/perf/Documentation/perf-lock.txt +++ b/tools/perf/Documentation/perf-lock.txt @@ -208,6 +208,9 @@ CONTENTION OPTIONS Show results using a CSV-style output to make it easy to import directly into spreadsheets. Columns are separated by the string specified in SEP. +--lock-cgroup:: + Show lock contention stat by cgroup. Requires --use-bpf. + SEE ALSO -------- diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c index 06430980dfd7..03d82f5a9afc 100644 --- a/tools/perf/builtin-lock.c +++ b/tools/perf/builtin-lock.c @@ -60,6 +60,7 @@ static bool combine_locks; static bool show_thread_stats; static bool show_lock_addrs; static bool show_lock_owner; +static bool show_lock_cgroups; static bool use_bpf; static unsigned long bpf_map_entries = MAX_ENTRIES; static int max_stack_depth = CONTENTION_STACK_DEPTH; @@ -619,6 +620,7 @@ static int get_key_by_aggr_mode_simple(u64 *key, u64 addr, u32 tid) *key = tid; break; case LOCK_AGGR_CALLER: + case LOCK_AGGR_CGROUP: default: pr_err("Invalid aggregation mode: %d\n", aggr_mode); return -EINVAL; @@ -1103,6 +1105,7 @@ static int report_lock_contention_begin_event(struct evsel *evsel, if (lock_contention_caller(evsel, sample, buf, sizeof(buf)) < 0) name = "Unknown"; break; + case LOCK_AGGR_CGROUP: case LOCK_AGGR_TASK: default: break; @@ -1653,6 +1656,9 @@ static void print_header_stdio(void) case LOCK_AGGR_ADDR: fprintf(lock_output, " %16s %s\n\n", "address", "symbol"); break; + case LOCK_AGGR_CGROUP: + fprintf(lock_output, " %s\n\n", "cgroup"); + break; default: break; } @@ -1680,6 +1686,9 @@ static void print_header_csv(const char *sep) case LOCK_AGGR_ADDR: fprintf(lock_output, "%s%s %s%s %s\n", "address", sep, "symbol", sep, "type"); break; + case LOCK_AGGR_CGROUP: + fprintf(lock_output, "%s\n", "cgroup"); + break; default: break; } @@ -1720,6 +1729,9 @@ static void print_lock_stat_stdio(struct lock_contention *con, struct lock_stat fprintf(lock_output, " %016llx %s (%s)\n", (unsigned long long)st->addr, st->name, get_type_name(st->flags)); break; + case LOCK_AGGR_CGROUP: + fprintf(lock_output, " %s\n", st->name); + break; default: break; } @@ -1770,6 +1782,9 @@ static void print_lock_stat_csv(struct lock_contention *con, struct lock_stat *s fprintf(lock_output, "%llx%s %s%s %s\n", (unsigned long long)st->addr, sep, st->name, sep, get_type_name(st->flags)); break; + case LOCK_AGGR_CGROUP: + fprintf(lock_output, "%s\n",st->name); + break; default: break; } @@ -1999,6 +2014,27 @@ static int check_lock_contention_options(const struct option *options, return -1; } + if (show_lock_cgroups && !use_bpf) { + pr_err("Cgroups are available only with BPF\n"); + parse_options_usage(usage, options, "lock-cgroup", 0); + parse_options_usage(NULL, options, "use-bpf", 0); + return -1; + } + + if (show_lock_cgroups && show_lock_addrs) { + pr_err("Cannot use cgroup and addr mode together\n"); + parse_options_usage(usage, options, "lock-cgroup", 0); + parse_options_usage(NULL, options, "lock-addr", 0); + return -1; + } + + if (show_lock_cgroups && show_thread_stats) { + pr_err("Cannot use cgroup and thread mode together\n"); + parse_options_usage(usage, options, "lock-cgroup", 0); + parse_options_usage(NULL, options, "threads", 0); + return -1; + } + if (symbol_conf.field_sep) { if (strstr(symbol_conf.field_sep, ":") || /* part of type flags */ strstr(symbol_conf.field_sep, "+") || /* part of caller offset */ @@ -2060,7 +2096,8 @@ static int __cmd_contention(int argc, const char **argv) con.machine = &session->machines.host; con.aggr_mode = aggr_mode = show_thread_stats ? LOCK_AGGR_TASK : - show_lock_addrs ? LOCK_AGGR_ADDR : LOCK_AGGR_CALLER; + show_lock_addrs ? LOCK_AGGR_ADDR : + show_lock_cgroups ? LOCK_AGGR_CGROUP : LOCK_AGGR_CALLER; if (con.aggr_mode == LOCK_AGGR_CALLER) con.save_callstack = true; @@ -2524,6 +2561,7 @@ int cmd_lock(int argc, const char **argv) OPT_BOOLEAN('o', "lock-owner", &show_lock_owner, "show lock owners instead of waiters"), OPT_STRING_NOEMPTY('x', "field-separator", &symbol_conf.field_sep, "separator", "print result in CSV format with custom separator"), + OPT_BOOLEAN(0, "lock-cgroup", &show_lock_cgroups, "show lock stats by cgroup"), OPT_PARENT(lock_options) }; diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c index c6bd7c9b2d57..42753a0dfdc5 100644 --- a/tools/perf/util/bpf_lock_contention.c +++ b/tools/perf/util/bpf_lock_contention.c @@ -152,7 +152,10 @@ int lock_contention_prepare(struct lock_contention *con) skel->bss->needs_callstack = con->save_callstack; skel->bss->lock_owner = con->owner; - if (con->use_cgroup) { + if (con->aggr_mode == LOCK_AGGR_CGROUP) { + if (cgroup_is_v2("perf_event")) + skel->bss->use_cgroup_v2 = 1; + read_all_cgroups(&con->cgroups); } @@ -214,12 +217,12 @@ static const char *lock_contention_get_name(struct lock_contention *con, return "siglock"; /* global locks with symbols */ - sym = machine__find_kernel_symbol(machine, key->lock_addr, &kmap); + sym = machine__find_kernel_symbol(machine, key->lock_addr_or_cgroup, &kmap); if (sym) return sym->name; /* try semi-global locks collected separately */ - if (!bpf_map_lookup_elem(lock_fd, &key->lock_addr, &flags)) { + if (!bpf_map_lookup_elem(lock_fd, &key->lock_addr_or_cgroup, &flags)) { if (flags == LOCK_CLASS_RQLOCK) return "rq_lock"; } @@ -227,8 +230,8 @@ static const char *lock_contention_get_name(struct lock_contention *con, return ""; } - if (con->use_cgroup) { - u64 cgrp_id = key->lock_addr; + if (con->aggr_mode == LOCK_AGGR_CGROUP) { + u64 cgrp_id = key->lock_addr_or_cgroup; struct cgroup *cgrp = __cgroup__find(&con->cgroups, cgrp_id); if (cgrp) @@ -329,7 +332,8 @@ int lock_contention_read(struct lock_contention *con) ls_key = key.pid; break; case LOCK_AGGR_ADDR: - ls_key = key.lock_addr; + case LOCK_AGGR_CGROUP: + ls_key = key.lock_addr_or_cgroup; break; default: goto next; diff --git a/tools/perf/util/bpf_skel/lock_contention.bpf.c b/tools/perf/util/bpf_skel/lock_contention.bpf.c index 8d3cfbb3cc65..823354999022 100644 --- a/tools/perf/util/bpf_skel/lock_contention.bpf.c +++ b/tools/perf/util/bpf_skel/lock_contention.bpf.c @@ -118,6 +118,9 @@ int needs_callstack; int stack_skip; int lock_owner; +int use_cgroup_v2; +int perf_subsys_id = -1; + /* determine the key of lock stat */ int aggr_mode; @@ -130,6 +133,29 @@ int data_fail; int task_map_full; int data_map_full; +static inline __u64 get_current_cgroup_id(void) +{ + struct task_struct *task; + struct cgroup *cgrp; + + if (use_cgroup_v2) + return bpf_get_current_cgroup_id(); + + task = bpf_get_current_task_btf(); + + if (perf_subsys_id == -1) { +#if __has_builtin(__builtin_preserve_enum_value) + perf_subsys_id = bpf_core_enum_value(enum cgroup_subsys_id, + perf_event_cgrp_id); +#else + perf_subsys_id = perf_event_cgrp_id; +#endif + } + + cgrp = BPF_CORE_READ(task, cgroups, subsys[perf_subsys_id], cgroup); + return BPF_CORE_READ(cgrp, kn, id); +} + static inline int can_record(u64 *ctx) { if (has_cpu) { @@ -364,10 +390,13 @@ int contention_end(u64 *ctx) key.stack_id = pelem->stack_id; break; case LOCK_AGGR_ADDR: - key.lock_addr = pelem->lock; + key.lock_addr_or_cgroup = pelem->lock; if (needs_callstack) key.stack_id = pelem->stack_id; break; + case LOCK_AGGR_CGROUP: + key.lock_addr_or_cgroup = get_current_cgroup_id(); + break; default: /* should not happen */ return 0; diff --git a/tools/perf/util/bpf_skel/lock_data.h b/tools/perf/util/bpf_skel/lock_data.h index 260062a9f2ab..08482daf61be 100644 --- a/tools/perf/util/bpf_skel/lock_data.h +++ b/tools/perf/util/bpf_skel/lock_data.h @@ -6,7 +6,7 @@ struct contention_key { u32 stack_id; u32 pid; - u64 lock_addr; + u64 lock_addr_or_cgroup; }; #define TASK_COMM_LEN 16 @@ -39,6 +39,7 @@ enum lock_aggr_mode { LOCK_AGGR_ADDR = 0, LOCK_AGGR_TASK, LOCK_AGGR_CALLER, + LOCK_AGGR_CGROUP, }; enum lock_class_sym { diff --git a/tools/perf/util/lock-contention.h b/tools/perf/util/lock-contention.h index 70423966d778..a073cc6a82d2 100644 --- a/tools/perf/util/lock-contention.h +++ b/tools/perf/util/lock-contention.h @@ -144,7 +144,6 @@ struct lock_contention { int owner; int nr_filtered; bool save_callstack; - bool use_cgroup; }; #ifdef HAVE_BPF_SKEL -- cgit v1.2.3