]> git.itanic.dy.fi Git - linux-stable/commitdiff
perf lock contention: Add -G/--cgroup-filter option
authorNamhyung Kim <namhyung@kernel.org>
Wed, 6 Sep 2023 17:49:02 +0000 (10:49 -0700)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Tue, 12 Sep 2023 20:32:00 +0000 (17:32 -0300)
The -G/--cgroup-filter is to limit lock contention collection on the
tasks in the specific cgroups only.

  $ sudo ./perf lock con -abt -G /user.slice/.../vte-spawn-52221fb8-b33f-4a52-b5c3-e35d1e6fc0e0.scope \
    ./perf bench sched messaging
  # Running 'sched/messaging' benchmark:
  # 20 sender and receiver processes per group
  # 10 groups == 400 processes run

       Total time: 0.174 [sec]
   contended   total wait     max wait     avg wait          pid   comm

           4    114.45 us     60.06 us     28.61 us       214847   sched-messaging
           2    111.40 us     60.84 us     55.70 us       214848   sched-messaging
           2    106.09 us     59.42 us     53.04 us       214837   sched-messaging
           1     81.70 us     81.70 us     81.70 us       214709   sched-messaging
          68     78.44 us      6.83 us      1.15 us       214633   sched-messaging
          69     73.71 us      2.69 us      1.07 us       214632   sched-messaging
           4     72.62 us     60.83 us     18.15 us       214850   sched-messaging
           2     71.75 us     67.60 us     35.88 us       214840   sched-messaging
           2     69.29 us     67.53 us     34.65 us       214804   sched-messaging
           2     69.00 us     68.23 us     34.50 us       214826   sched-messaging
  ...

Export cgroup__new() function as it's needed from outside.

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230906174903.346486-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/Documentation/perf-lock.txt
tools/perf/builtin-lock.c
tools/perf/util/bpf_lock_contention.c
tools/perf/util/bpf_skel/lock_contention.bpf.c
tools/perf/util/cgroup.c
tools/perf/util/cgroup.h
tools/perf/util/lock-contention.h

index 4b5cdf4b33c6f838d98164e3645ddf00da50cab2..503abcba1438038732cff8afcfab5012feed0fc5 100644 (file)
@@ -211,6 +211,10 @@ CONTENTION OPTIONS
 --lock-cgroup::
        Show lock contention stat by cgroup.  Requires --use-bpf.
 
+-G::
+--cgroup-filter=<value>::
+       Show lock contention only in the given cgroups (comma separated list).
+
 
 SEE ALSO
 --------
index 03d82f5a9afc0e597f605f3d9512ba5f992ddcbf..d4b22313e5fca43c6334a6708ee2b3f4f2fc0c0b 100644 (file)
@@ -10,6 +10,7 @@
 #include "util/thread.h"
 #include "util/header.h"
 #include "util/target.h"
+#include "util/cgroup.h"
 #include "util/callchain.h"
 #include "util/lock-contention.h"
 #include "util/bpf_skel/lock_data.h"
@@ -1631,6 +1632,9 @@ static void lock_filter_finish(void)
 
        zfree(&filters.syms);
        filters.nr_syms = 0;
+
+       zfree(&filters.cgrps);
+       filters.nr_cgrps = 0;
 }
 
 static void sort_contention_result(void)
@@ -2488,6 +2492,56 @@ static int parse_output(const struct option *opt __maybe_unused, const char *str
        return 0;
 }
 
+static bool add_lock_cgroup(char *name)
+{
+       u64 *tmp;
+       struct cgroup *cgrp;
+
+       cgrp = cgroup__new(name, /*do_open=*/false);
+       if (cgrp == NULL) {
+               pr_err("Failed to create cgroup: %s\n", name);
+               return false;
+       }
+
+       if (read_cgroup_id(cgrp) < 0) {
+               pr_err("Failed to read cgroup id for %s\n", name);
+               cgroup__put(cgrp);
+               return false;
+       }
+
+       tmp = realloc(filters.cgrps, (filters.nr_cgrps + 1) * sizeof(*filters.cgrps));
+       if (tmp == NULL) {
+               pr_err("Memory allocation failure\n");
+               return false;
+       }
+
+       tmp[filters.nr_cgrps++] = cgrp->id;
+       filters.cgrps = tmp;
+       cgroup__put(cgrp);
+       return true;
+}
+
+static int parse_cgroup_filter(const struct option *opt __maybe_unused, const char *str,
+                              int unset __maybe_unused)
+{
+       char *s, *tmp, *tok;
+       int ret = 0;
+
+       s = strdup(str);
+       if (s == NULL)
+               return -1;
+
+       for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) {
+               if (!add_lock_cgroup(tok)) {
+                       ret = -1;
+                       break;
+               }
+       }
+
+       free(s);
+       return ret;
+}
+
 int cmd_lock(int argc, const char **argv)
 {
        const struct option lock_options[] = {
@@ -2562,6 +2616,8 @@ int cmd_lock(int argc, const char **argv)
        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_CALLBACK('G', "cgroup-filter", NULL, "CGROUPS",
+                    "Filter specific cgroups", parse_cgroup_filter),
        OPT_PARENT(lock_options)
        };
 
index 42753a0dfdc5e8fec6bdd062fad469aa35884ccd..e105245eb905d2436ad754589f301e1e1283fa2e 100644 (file)
@@ -21,7 +21,7 @@ static struct lock_contention_bpf *skel;
 int lock_contention_prepare(struct lock_contention *con)
 {
        int i, fd;
-       int ncpus = 1, ntasks = 1, ntypes = 1, naddrs = 1;
+       int ncpus = 1, ntasks = 1, ntypes = 1, naddrs = 1, ncgrps = 1;
        struct evlist *evlist = con->evlist;
        struct target *target = con->target;
 
@@ -51,6 +51,8 @@ int lock_contention_prepare(struct lock_contention *con)
                ntasks = perf_thread_map__nr(evlist->core.threads);
        if (con->filters->nr_types)
                ntypes = con->filters->nr_types;
+       if (con->filters->nr_cgrps)
+               ncgrps = con->filters->nr_cgrps;
 
        /* resolve lock name filters to addr */
        if (con->filters->nr_syms) {
@@ -85,6 +87,7 @@ int lock_contention_prepare(struct lock_contention *con)
        bpf_map__set_max_entries(skel->maps.task_filter, ntasks);
        bpf_map__set_max_entries(skel->maps.type_filter, ntypes);
        bpf_map__set_max_entries(skel->maps.addr_filter, naddrs);
+       bpf_map__set_max_entries(skel->maps.cgroup_filter, ncgrps);
 
        if (lock_contention_bpf__load(skel) < 0) {
                pr_err("Failed to load lock-contention BPF skeleton\n");
@@ -146,6 +149,16 @@ int lock_contention_prepare(struct lock_contention *con)
                        bpf_map_update_elem(fd, &con->filters->addrs[i], &val, BPF_ANY);
        }
 
+       if (con->filters->nr_cgrps) {
+               u8 val = 1;
+
+               skel->bss->has_cgroup = 1;
+               fd = bpf_map__fd(skel->maps.cgroup_filter);
+
+               for (i = 0; i < con->filters->nr_cgrps; i++)
+                       bpf_map_update_elem(fd, &con->filters->cgrps[i], &val, BPF_ANY);
+       }
+
        /* these don't work well if in the rodata section */
        skel->bss->stack_skip = con->stack_skip;
        skel->bss->aggr_mode = con->aggr_mode;
index 823354999022d073050cf621d9f26a23d896d8e3..4900a5dfb4a4d9cc5aaed7b5c40b368aee01f760 100644 (file)
@@ -92,6 +92,13 @@ struct {
        __uint(max_entries, 1);
 } addr_filter SEC(".maps");
 
+struct {
+       __uint(type, BPF_MAP_TYPE_HASH);
+       __uint(key_size, sizeof(__u64));
+       __uint(value_size, sizeof(__u8));
+       __uint(max_entries, 1);
+} cgroup_filter SEC(".maps");
+
 struct rw_semaphore___old {
        struct task_struct *owner;
 } __attribute__((preserve_access_index));
@@ -114,6 +121,7 @@ int has_cpu;
 int has_task;
 int has_type;
 int has_addr;
+int has_cgroup;
 int needs_callstack;
 int stack_skip;
 int lock_owner;
@@ -194,6 +202,15 @@ static inline int can_record(u64 *ctx)
                        return 0;
        }
 
+       if (has_cgroup) {
+               __u8 *ok;
+               __u64 cgrp = get_current_cgroup_id();
+
+               ok = bpf_map_lookup_elem(&cgroup_filter, &cgrp);
+               if (!ok)
+                       return 0;
+       }
+
        return 1;
 }
 
index d03651098dde811b851b7bfcae6af7b053a9732a..fcb50905849969b380cea44432bda5fa76cf0d01 100644 (file)
@@ -114,7 +114,7 @@ static struct cgroup *evlist__find_cgroup(struct evlist *evlist, const char *str
        return NULL;
 }
 
-static struct cgroup *cgroup__new(const char *name, bool do_open)
+struct cgroup *cgroup__new(const char *name, bool do_open)
 {
        struct cgroup *cgroup = zalloc(sizeof(*cgroup));
 
index beb6fe1012ede629a56e8c364c5a2faf9e76bace..de8882d6e8d3f2a97efe277a54fa16b38dc5483d 100644 (file)
@@ -26,6 +26,7 @@ void cgroup__put(struct cgroup *cgroup);
 struct evlist;
 struct rblist;
 
+struct cgroup *cgroup__new(const char *name, bool do_open);
 struct cgroup *evlist__findnew_cgroup(struct evlist *evlist, const char *name);
 int evlist__expand_cgroup(struct evlist *evlist, const char *cgroups,
                          struct rblist *metric_events, bool open_cgroup);
index a073cc6a82d229782fd4242e5d2a00b1d70bfc30..1a7248ff388947e12b5cc109a88c8ac924dbc40c 100644 (file)
@@ -9,9 +9,11 @@ struct lock_filter {
        int                     nr_types;
        int                     nr_addrs;
        int                     nr_syms;
+       int                     nr_cgrps;
        unsigned int            *types;
        unsigned long           *addrs;
        char                    **syms;
+       u64                     *cgrps;
 };
 
 struct lock_stat {