Em Wed, Jan 29, 2014 at 04:14:44PM +0200, Adrian Hunter escreveu:
> perf buildid-cache does not make another
> copy of kcore if the buildid and modules
> match an existing copy. That does not
Humm, what is the problem? Having the ref reloc symbol we can fix things
up, no? I.e. just using map->reloc the old kcore copy should be ok to
use, no need to replace the kcore copy in the cache. Or am I missing
something?
- Arnaldo
> take into account the possibility that
> the kernel has been relocated. Extend
> the check to check if the reference
> relocation symbol matches too, otherwise
> do make a copy.
>
> Signed-off-by: Adrian Hunter <adrian.hun...@intel.com>
> ---
> tools/perf/builtin-buildid-cache.c | 33 +++++++++++++++++++++++++++++----
> 1 file changed, 29 insertions(+), 4 deletions(-)
>
> diff --git a/tools/perf/builtin-buildid-cache.c
> b/tools/perf/builtin-buildid-cache.c
> index cfede86..b22dbb1 100644
> --- a/tools/perf/builtin-buildid-cache.c
> +++ b/tools/perf/builtin-buildid-cache.c
> @@ -63,11 +63,35 @@ static int build_id_cache__kcore_dir(char *dir, size_t sz)
> return 0;
> }
>
> +static bool same_kallsyms_reloc(const char *from_dir, char *to_dir)
> +{
> + char from[PATH_MAX];
> + char to[PATH_MAX];
> + const char *name;
> + u64 addr1 = 0, addr2 = 0;
> + int i;
> +
> + scnprintf(from, sizeof(from), "%s/kallsyms", from_dir);
> + scnprintf(to, sizeof(to), "%s/kallsyms", to_dir);
> +
> + for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
> + addr1 = kallsyms__get_function_start(from, name);
> + if (addr1)
> + break;
> + }
> +
> + if (name)
> + addr2 = kallsyms__get_function_start(to, name);
> +
> + return addr1 == addr2;
> +}
> +
> static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
> size_t to_dir_sz)
> {
> char from[PATH_MAX];
> char to[PATH_MAX];
> + char to_subdir[PATH_MAX];
> struct dirent *dent;
> int ret = -1;
> DIR *d;
> @@ -86,10 +110,11 @@ static int build_id_cache__kcore_existing(const char
> *from_dir, char *to_dir,
> continue;
> scnprintf(to, sizeof(to), "%s/%s/modules", to_dir,
> dent->d_name);
> - if (!compare_proc_modules(from, to)) {
> - scnprintf(to, sizeof(to), "%s/%s", to_dir,
> - dent->d_name);
> - strlcpy(to_dir, to, to_dir_sz);
> + scnprintf(to_subdir, sizeof(to_subdir), "%s/%s",
> + to_dir, dent->d_name);
> + if (!compare_proc_modules(from, to) &&
> + same_kallsyms_reloc(from_dir, to_subdir)) {
> + strlcpy(to_dir, to_subdir, to_dir_sz);
> ret = 0;
> break;
> }
> --
> 1.7.11.7
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