perf buildid-cache does not make another copy of kcore if the buildid and modules match an existing copy. That does not 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/