Em Wed, Aug 30, 2023 at 04:01:22PM -0700, Namhyung Kim escreveu:
> The read_all_cgroups() is to build a tree of cgroups in the system and
> users can look up a cgroup using __cgroup_find().
⬢[acme@toolbox perf-tools-next]$ alias m='make -k BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools-next -C tools/perf install-bin && git status && perf test python'
⬢[acme@toolbox perf-tools-next]$ m
make: Entering directory '/var/home/acme/git/perf-tools-next/tools/perf'
BUILD: Doing 'make -j32' parallel build
Warning: Kernel ABI header differences:
diff -u tools/include/uapi/linux/perf_event.h include/uapi/linux/perf_event.h
diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h
diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h
diff -u tools/arch/arm64/include/uapi/asm/perf_regs.h arch/arm64/include/uapi/asm/perf_regs.h
INSTALL libsubcmd_headers
INSTALL libperf_headers
INSTALL libapi_headers
INSTALL libsymbol_headers
INSTALL libbpf_headers
CC /tmp/build/perf-tools-next/builtin-lock.o
CC /tmp/build/perf-tools-next/util/bpf_lock_contention.o
builtin-lock.c: In function ‘__cmd_contention’:
builtin-lock.c:2162:9: error: too few arguments to function ‘lock_contention_finish’
2162 | lock_contention_finish();
| ^~~~~~~~~~~~~~~~~~~~~~
In file included from builtin-lock.c:14:
util/lock-contention.h:156:5: note: declared here
156 | int lock_contention_finish(struct lock_contention *con);
| ^~~~~~~~~~~~~~~~~~~~~~
make[3]: *** [/var/home/acme/git/perf-tools-next/tools/build/Makefile.build:97: /tmp/build/perf-tools-next/builtin-lock.o] Error 1
make[3]: *** Waiting for unfinished jobs....
util/bpf_lock_contention.c: In function ‘lock_contention_get_name’:
util/bpf_lock_contention.c:231:34: error: ‘struct contention_key’ has no member named ‘lock_addr_or_cgroup’
231 | u64 cgrp_id = key->lock_addr_or_cgroup;
| ^~
make[4]: *** [/var/home/acme/git/perf-tools-next/tools/build/Makefile.build:97: /tmp/build/perf-tools-next/util/bpf_lock_contention.o] Error 1
make[3]: *** [/var/home/acme/git/perf-tools-next/tools/build/Makefile.build:150: util] Error 2
make[2]: *** [Makefile.perf:662: /tmp/build/perf-tools-next/perf-in.o] Error 2
make[1]: *** [Makefile.perf:238: sub-make] Error 2
make: *** [Makefile:113: install-bin] Error 2
make: Leaving directory '/var/home/acme/git/perf-tools-next/tools/perf'
⬢[acme@toolbox perf-tools-next]$
Trying to figure this out.
- Arnaldo
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
> tools/perf/util/cgroup.c | 61 ++++++++++++++++++++++++++++++++++------
> tools/perf/util/cgroup.h | 4 +++
> 2 files changed, 57 insertions(+), 8 deletions(-)
>
> diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
> index bfb13306d82c..2e969d1464f4 100644
> --- a/tools/perf/util/cgroup.c
> +++ b/tools/perf/util/cgroup.c
> @@ -48,28 +48,36 @@ static int open_cgroup(const char *name)
> }
>
> #ifdef HAVE_FILE_HANDLE
> -int read_cgroup_id(struct cgroup *cgrp)
> +static u64 __read_cgroup_id(const char *path)
> {
> - char path[PATH_MAX + 1];
> - char mnt[PATH_MAX + 1];
> struct {
> struct file_handle fh;
> uint64_t cgroup_id;
> } handle;
> int mount_id;
>
> + handle.fh.handle_bytes = sizeof(handle.cgroup_id);
> + if (name_to_handle_at(AT_FDCWD, path, &handle.fh, &mount_id, 0) < 0)
> + return -1ULL;
> +
> + return handle.cgroup_id;
> +}
> +
> +int read_cgroup_id(struct cgroup *cgrp)
> +{
> + char path[PATH_MAX + 1];
> + char mnt[PATH_MAX + 1];
> +
> if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1, "perf_event"))
> return -1;
>
> scnprintf(path, PATH_MAX, "%s/%s", mnt, cgrp->name);
>
> - handle.fh.handle_bytes = sizeof(handle.cgroup_id);
> - if (name_to_handle_at(AT_FDCWD, path, &handle.fh, &mount_id, 0) < 0)
> - return -1;
> -
> - cgrp->id = handle.cgroup_id;
> + cgrp->id = __read_cgroup_id(path);
> return 0;
> }
> +#else
> +static inline u64 __read_cgroup_id(const char *path) { return -1ULL; }
> #endif /* HAVE_FILE_HANDLE */
>
> #ifndef CGROUP2_SUPER_MAGIC
> @@ -562,6 +570,11 @@ struct cgroup *cgroup__findnew(struct perf_env *env, uint64_t id,
> return cgrp;
> }
>
> +struct cgroup *__cgroup__find(struct rb_root *root, uint64_t id)
> +{
> + return __cgroup__findnew(root, id, /*create=*/false, /*path=*/NULL);
> +}
> +
> struct cgroup *cgroup__find(struct perf_env *env, uint64_t id)
> {
> struct cgroup *cgrp;
> @@ -587,3 +600,35 @@ void perf_env__purge_cgroups(struct perf_env *env)
> }
> up_write(&env->cgroups.lock);
> }
> +
> +void read_all_cgroups(struct rb_root *root)
> +{
> + char mnt[PATH_MAX];
> + struct cgroup_name *cn;
> + int prefix_len;
> +
> + if (cgroupfs_find_mountpoint(mnt, sizeof(mnt), "perf_event"))
> + return;
> +
> + /* cgroup_name will have a full path, skip the root directory */
> + prefix_len = strlen(mnt);
> +
> + /* collect all cgroups in the cgroup_list */
> + if (nftw(mnt, add_cgroup_name, 20, 0) < 0)
> + return;
> +
> + list_for_each_entry(cn, &cgroup_list, list) {
> + const char *name;
> + u64 cgrp_id;
> +
> + /* cgroup_name might have a full path, skip the prefix */
> + name = cn->name + prefix_len;
> + if (name[0] == '\0')
> + name = "/";
> +
> + cgrp_id = __read_cgroup_id(cn->name);
> + __cgroup__findnew(root, cgrp_id, /*create=*/true, name);
> + }
> +
> + release_cgroup_list();
> +}
> diff --git a/tools/perf/util/cgroup.h b/tools/perf/util/cgroup.h
> index 12256b78608c..beb6fe1012ed 100644
> --- a/tools/perf/util/cgroup.h
> +++ b/tools/perf/util/cgroup.h
> @@ -37,6 +37,7 @@ int parse_cgroups(const struct option *opt, const char *str, int unset);
> struct cgroup *cgroup__findnew(struct perf_env *env, uint64_t id,
> const char *path);
> struct cgroup *cgroup__find(struct perf_env *env, uint64_t id);
> +struct cgroup *__cgroup__find(struct rb_root *root, uint64_t id);
>
> void perf_env__purge_cgroups(struct perf_env *env);
>
> @@ -49,6 +50,9 @@ static inline int read_cgroup_id(struct cgroup *cgrp __maybe_unused)
> }
> #endif /* HAVE_FILE_HANDLE */
>
> +/* read all cgroups in the system and save them in the rbtree */
> +void read_all_cgroups(struct rb_root *root);
> +
> int cgroup_is_v2(const char *subsys);
>
> #endif /* __CGROUP_H__ */
> --
> 2.42.0.283.g2d96d420d3-goog
>
--
- Arnaldo
