[libvirt] [PATCH 44/53] vircgroupmock: add support to test cgroup v2

[Michal Privoznik]

On 10/02/2018 10:44 AM, Pavel Hrdina wrote:
> We need to create the cgroup v2 sysfs the same way as we do for
> cgroup v1.
> 
> This introduces new VIR_CGROUP_MOCK_MODE env variable which will
> configure which cgroup mode each test requires.  There are three
> different modes:
> 
>     - legacy: only cgroup v1 is available and it's the default mode
>     - hybrid: both cgroup v1 and cgroup v2 are available and have some
>         controllers
>     - unified: only cgroup v2 is available
> 
> Signed-off-by: Pavel Hrdina <phrdina at redhat.com>
> ---
>  tests/vircgroupmock.c | 153 +++++++++++++++++++++++++++++++++++++-----
>  1 file changed, 138 insertions(+), 15 deletions(-)
> 
> diff --git a/tests/vircgroupmock.c b/tests/vircgroupmock.c
> index 5c48ef012a..1ed00ea91c 100644
> --- a/tests/vircgroupmock.c
> +++ b/tests/vircgroupmock.c
> @@ -105,7 +105,8 @@ static int make_file(const char *path,
>      return ret;
>  }
>  
> -static int make_controller(const char *path, mode_t mode)
> +
> +static int make_controller_v1(const char *path, mode_t mode)
>  {
>      int ret = -1;
>      const char *controller;
> @@ -231,11 +232,86 @@ static int make_controller(const char *path, mode_t mode)
>          goto cleanup;
>      }
>  
> +# undef MAKE_FILE
> +
>      ret = 0;
>   cleanup:
>      return ret;
>  }
>  
> +
> +static int make_controller_v2(const char *path, mode_t mode)
> +{
> +    if (!STRPREFIX(path, fakesysfscgroupdir)) {
> +        errno = EINVAL;
> +        return -1;
> +    }
> +
> +    if (real_mkdir(path, mode) < 0 && errno != EEXIST)
> +        return -1;
> +
> +# define MAKE_FILE(name, value) \
> +    do { \
> +        if (make_file(path, name, value) < 0) \
> +            return -1; \
> +    } while (0)
> +
> +    MAKE_FILE("cgroup.controllers", "cpu io memory\n");
> +    MAKE_FILE("cgroup.subtree_control", "");
> +    MAKE_FILE("cgroup.type", "domain\n");
> +    MAKE_FILE("cpu.max", "max 100000\n");
> +    MAKE_FILE("cpu.stat",
> +              "usage_usec 0\n"
> +              "user_usec 0\n"
> +              "system_usec 0\n"
> +              "nr_periods 0\n"
> +              "nr_throttled 0\n"
> +              "throttled_usec 0\n");
> +    MAKE_FILE("cpu.weight", "100\n");
> +    MAKE_FILE("memory.current", "1455321088\n");
> +    MAKE_FILE("memory.high", "max\n");
> +    MAKE_FILE("memory.max", "max\n");
> +    MAKE_FILE("memory.stat",
> +              "anon 0\n"
> +              "file 0\n"
> +              "kernel_stack 0\n"
> +              "slab 0\n"
> +              "sock 0\n"
> +              "shmem 0\n"
> +              "file_mapped 0\n"
> +              "file_dirty 0\n"
> +              "file_writeback 0\n"
> +              "inactive_anon 0\n"
> +              "active_anon 0\n"
> +              "inactive_file 0\n"
> +              "active_file 0\n"
> +              "unevictable 0\n"
> +              "slab_reclaimable 0\n"
> +              "slab_unreclaimable 0\n"
> +              "pgfault 0\n"
> +              "pgmajfault 0\n"
> +              "pgrefill 0\n"
> +              "pgscan 0\n"
> +              "pgsteal 0\n"
> +              "pgactivate 0\n"
> +              "pgdeactivate 0\n"
> +              "pglazyfree 0\n"
> +              "pglazyfreed 0\n"
> +              "workingset_refault 0\n"
> +              "workingset_activate 0\n"
> +              "workingset_nodereclaim 0\n");
> +    MAKE_FILE("memory.swap.current", "0\n");
> +    MAKE_FILE("memory.swap.max", "max\n");
> +    MAKE_FILE("io.stat", "8:0 rbytes=26828800 wbytes=77062144 rios=2256 wios=7849 dbytes=0 dios=0\n");
> +    MAKE_FILE("io.max", "");
> +    MAKE_FILE("io.weight", "default 100\n");
> +
> +# undef MAKE_FILE
> +
> +    return 0;
> +}
> +
> +
>  static void init_syms(void)
>  {
>      if (real_fopen)
> @@ -249,16 +325,56 @@ static void init_syms(void)
>      VIR_MOCK_REAL_INIT(open);
>  }
>  
> +
> +static int make_controller(const char *path, mode_t mode)
> +{
> +    const char *mock;
> +    bool unified = false;
> +    bool hybrid = false;
> +
> +    mock = getenv("VIR_CGROUP_MOCK_MODE");
> +    if (mock) {
> +        if (STREQ(mock, "unified"))
> +            unified = true;
> +        else if (STREQ(mock, "hybrid"))
> +            hybrid = true;
> +    }
> +
> +    if (unified || (hybrid && strstr(path, "unified"))) {
> +        return make_controller_v2(path, mode);
> +    } else {
> +        return make_controller_v1(path, mode);
> +    }
> +}
> +
> +
>  static void init_sysfs(void)
>  {
> -    if (fakerootdir && fakesysfscgroupdir)
> -        return;
> +    const char *mock;
> +    char *newfakerootdir;
> +    bool unified = false;
> +    bool hybrid = false;
>  
> -    if (!(fakerootdir = getenv("LIBVIRT_FAKE_ROOT_DIR"))) {
> +    if (!(newfakerootdir = getenv("LIBVIRT_FAKE_ROOT_DIR"))) {
>          fprintf(stderr, "Missing LIBVIRT_FAKE_ROOT_DIR env variable\n");
>          abort();
>      }
>  
> +    if (fakerootdir && STREQ(fakerootdir, newfakerootdir))

or simply STREQ_NULLABLE()

> +        return;
> +
> +    fakerootdir = newfakerootdir;
> +
> +    mock = getenv("VIR_CGROUP_MOCK_MODE");
> +    if (mock) {
> +        if (STREQ(mock, "unified"))
> +            unified = true;
> +        else if (STREQ(mock, "hybrid"))
> +            hybrid = true;

abort(unknown mode $mock);

> +    }
> +
> +    VIR_FREE(fakesysfscgroupdir);
> +
>      if (virAsprintfQuiet(&fakesysfscgroupdir, "%s%s",
>                           fakerootdir, SYSFS_CGROUP_PREFIX) < 0)
>          abort();
> @@ -281,18 +397,25 @@ static void init_sysfs(void)
>          free(path); \
>      } while (0)
>  
> -    MAKE_CONTROLLER("cpu");
> -    MAKE_CONTROLLER("cpuacct");
> -    MAKE_CONTROLLER("cpu,cpuacct");
> -    MAKE_CONTROLLER("cpu,cpuacct/system");
> -    MAKE_CONTROLLER("cpuset");
> -    MAKE_CONTROLLER("blkio");
> -    MAKE_CONTROLLER("memory");
> -    MAKE_CONTROLLER("freezer");
> +    if (unified) {
> +        MAKE_CONTROLLER("");
> +    } else if (hybrid) {
> +        MAKE_CONTROLLER("unified");
> +        MAKE_CONTROLLER("cpuset");
> +        MAKE_CONTROLLER("freezer");
> +    } else {
> +        MAKE_CONTROLLER("cpu");
> +        MAKE_CONTROLLER("cpuacct");
> +        MAKE_CONTROLLER("cpu,cpuacct");
> +        MAKE_CONTROLLER("cpuset");
> +        MAKE_CONTROLLER("blkio");
> +        MAKE_CONTROLLER("memory");
> +        MAKE_CONTROLLER("freezer");
>  
> -    if (make_file(fakesysfscgroupdir,
> -                  SYSFS_CPU_PRESENT_MOCKED, "8-23,48-159\n") < 0)
> -        abort();
> +        if (make_file(fakesysfscgroupdir,
> +                      SYSFS_CPU_PRESENT_MOCKED, "8-23,48-159\n") < 0)
> +            abort();
> +    }
>  }
>  
>  
> 


ACK

Michal