From: Chenggang Qin <[email protected]> Vdso is only one in a system. It is not necessory to traverse the macine->user_dsos list when looking for the dso of vdso. The flag vdso_found should be replaced by a pointor that point to the dso of vdso. If the pointer is NULL, dso of vdso have not been created. Else, the pointor can be returned directly in function vdso__dso_findnew(). The list traversing can be avoided by this method. Thanks.
Cc: David Ahern <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Arjan van de Ven <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Yanmin Zhang <[email protected]> Cc: Wu Fengguang <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Andrew Morton <[email protected]> Signed-off-by: Chenggang Qin <[email protected]> --- tools/perf/util/vdso.c | 22 ++++++++-------------- 1 files changed, 8 insertions(+), 14 deletions(-) diff --git a/tools/perf/util/vdso.c b/tools/perf/util/vdso.c index 3915982..8022ef0 100644 --- a/tools/perf/util/vdso.c +++ b/tools/perf/util/vdso.c @@ -13,7 +13,7 @@ #include "symbol.h" #include "linux/string.h" -static bool vdso_found; +static struct dso *vdso_dso = NULL; static char vdso_file[] = "/tmp/perf-vdso.so-XXXXXX"; static int find_vdso_map(void **start, void **end) @@ -55,9 +55,6 @@ static char *get_file(void) size_t size; int fd; - if (vdso_found) - return vdso_file; - if (find_vdso_map(&start, &end)) return NULL; @@ -79,33 +76,30 @@ static char *get_file(void) out: free(buf); - vdso_found = (vdso != NULL); return vdso; } void vdso__exit(void) { - if (vdso_found) + if (vdso_dso) unlink(vdso_file); } struct dso *vdso__dso_findnew(struct list_head *head) { - struct dso *dso = dsos__find(head, VDSO__MAP_NAME, true); - - if (!dso) { + if (!vdso_dso) { char *file; file = get_file(); if (!file) return NULL; - dso = dso__new(VDSO__MAP_NAME); - if (dso != NULL) { - dsos__add(head, dso); - dso__set_long_name(dso, file); + vdso_dso = dso__new(VDSO__MAP_NAME); + if (vdso_dso != NULL) { + dsos__add(head, vdso_dso); + dso__set_long_name(vdso_dso, file); } } - return dso; + return vdso_dso; } -- 1.7.8.rc2.5.g815b -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
