lkml.org 
[lkml]   [2014]   [Nov]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Subject[PATCH v4 4/5] perf/sdt: Delete SDT events from cache
    From
    Date
    This patch adds the support to delete SDT events from the cache.
    To delete an event corresponding to a file, first the cache is read into
    the file_hash list. The key is calculated from the file name.
    And then, the file_list for that file_hash entry is traversed to find out
    the target file_list entry. Once, it is found, its contents are all freed up.

    # ./perf sdt-cache --del /usr/lib64/libc-2.16.so
    8 event(s) removed for /usr/lib64/libc-2.16.so

    Signed-off-by: Hemant Kumar <hemant@linux.vnet.ibm.com>
    ---
    tools/perf/Documentation/perf-sdt-cache.txt | 6 +++-
    tools/perf/builtin-sdt-cache.c | 21 +++++++++++++-
    tools/perf/util/parse-events.h | 1 +
    tools/perf/util/sdt.c | 41 +++++++++++++++++++++++++++
    4 files changed, 67 insertions(+), 2 deletions(-)

    diff --git a/tools/perf/Documentation/perf-sdt-cache.txt b/tools/perf/Documentation/perf-sdt-cache.txt
    index e57a867..523dcda 100644
    --- a/tools/perf/Documentation/perf-sdt-cache.txt
    +++ b/tools/perf/Documentation/perf-sdt-cache.txt
    @@ -8,7 +8,7 @@ perf-sdt-cache - Manage SDT events' cache.
    SYNOPSIS
    --------
    [verse]
    -'perf sdt-cache --add <file_name>'
    +'perf sdt-cache [--add | --del] <file_name>'
    'perf sdt-cache --dump'

    DESCRIPTION
    @@ -23,6 +23,10 @@ OPTIONS
    --add::
    Add SDT events in the specified file to the cache. Takes file name
    as an argument.
    +-d::
    +--del::
    + Remove SDT events in the specified file from the cache. Takes file as an
    + argument.
    -D::
    --dump::
    Dump the contents of SDT events cache onto stdout.
    diff --git a/tools/perf/builtin-sdt-cache.c b/tools/perf/builtin-sdt-cache.c
    index 11f41a2..b35d844 100644
    --- a/tools/perf/builtin-sdt-cache.c
    +++ b/tools/perf/builtin-sdt-cache.c
    @@ -16,6 +16,7 @@
    /* Session management structure */
    static struct {
    bool add;
    + bool del;
    bool dump;
    const char *target;
    } params;
    @@ -29,6 +30,16 @@ static int opt_add_sdt_events(const struct option *opt __maybe_unused,
    return 0;
    }

    +static int opt_del_sdt_events(const struct option *opt __maybe_unused,
    + const char *str, int unset __maybe_unused)
    +{
    + params.del = true;
    + params.target = str;
    +
    + return 0;
    +}
    +
    +
    static int opt_show_sdt_events(const struct option *opt __maybe_unused,
    const char *str, int unset __maybe_unused)
    {
    @@ -45,6 +56,9 @@ int cmd_sdt_cache(int argc, const char **argv, const char *prefix __maybe_unused
    OPT_CALLBACK('a', "add", NULL, "filename",
    "add SDT events from a file.",
    opt_add_sdt_events),
    + OPT_CALLBACK('d', "del", NULL, "filename",
    + "Remove SDT events corresponding to a file from the sdt cache.",
    + opt_del_sdt_events),
    OPT_CALLBACK_NOOPT('D', "dump", NULL, "show SDT events",
    "Read SDT events from cache and display.",
    opt_show_sdt_events),
    @@ -52,13 +66,14 @@ int cmd_sdt_cache(int argc, const char **argv, const char *prefix __maybe_unused
    };

    const char * const sdt_cache_usage[] = {
    - "perf sdt-cache --add filename",
    + "perf sdt-cache [--add | --del] filename",
    "perf sdt-cache --dump",
    NULL
    };

    set_option_flag(sdt_cache_options, 'a', "add", PARSE_OPT_EXCLUSIVE);
    set_option_flag(sdt_cache_options, 'D', "dump", PARSE_OPT_EXCLUSIVE);
    + set_option_flag(sdt_cache_options, 'd', "del", PARSE_OPT_EXCLUSIVE);

    argc = parse_options(argc, argv, sdt_cache_options,
    sdt_cache_usage,
    @@ -71,6 +86,10 @@ int cmd_sdt_cache(int argc, const char **argv, const char *prefix __maybe_unused
    ret = add_sdt_events(params.target);
    if (ret < 0)
    pr_err("Cannot add SDT events to cache\n");
    + } else if (params.del) {
    + ret = remove_sdt_events(params.target);
    + if (ret < 0)
    + pr_err("Cannot remove SDT events from cache\n");
    } else if (params.dump) {
    if (argc == 0) {
    ret = dump_sdt_events();
    diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
    index cca6859..cafdab6 100644
    --- a/tools/perf/util/parse-events.h
    +++ b/tools/perf/util/parse-events.h
    @@ -125,5 +125,6 @@ extern int valid_debugfs_mount(const char *debugfs);

    int add_sdt_events(const char *file);
    int dump_sdt_events(void);
    +int remove_sdt_events(const char *str);

    #endif /* __PERF_PARSE_EVENTS_H */
    diff --git a/tools/perf/util/sdt.c b/tools/perf/util/sdt.c
    index 5f70dd6..9dd7e4da 100644
    --- a/tools/perf/util/sdt.c
    +++ b/tools/perf/util/sdt.c
    @@ -192,6 +192,7 @@ static int file_hash_list__remove(struct hash_table *file_hash,
    nr_del = cleanup_sdt_note_list(&fse->sdt_list);
    hlist_del(&fse->file_list);
    free(fse);
    + break;
    }
    free(res_path);
    return nr_del;
    @@ -661,3 +662,43 @@ int dump_sdt_events(void)
    file_hash_list__cleanup(&file_hash);
    return ret;
    }
    +
    +/**
    + * remove_sdt_events: remove SDT events from cache
    + * @str: filename
    + *
    + * Removes the SDT events from the cache corresponding to the file name
    + * @str.
    + */
    +int remove_sdt_events(const char *str)
    +{
    + struct hash_table file_hash;
    + char *res_path;
    + int nr_del, ret = -ENOMEM;
    +
    + res_path = realpath(str, NULL);
    + if (!res_path) {
    + pr_err("%s: Bad file name\n", str);
    + goto out_err;
    + }
    + /* Initialize the hash_lists */
    + ret = file_hash_list__init(&file_hash);
    + if (ret < 0)
    + goto out;
    +
    + /* Remove the file_list entry from file_hash and update the file_hash */
    + nr_del = file_hash_list__remove(&file_hash, res_path);
    + if (nr_del > 0) {
    + printf("%4d event(s) removed for %s\n", nr_del, res_path);
    + flush_hash_list_to_cache(&file_hash);
    + ret = nr_del;
    + goto out;
    + } else if (!nr_del)
    + pr_err("Error: Events for %s not found\n", str);
    +
    +out:
    + free(res_path);
    + file_hash_list__cleanup(&file_hash);
    +out_err:
    + return ret;
    +}


    \
     
     \ /
      Last update: 2014-11-02 14:21    [W:4.721 / U:0.496 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site