path: root/tools/perf/util/namespaces.h
diff options
authorJiri Olsa <jolsa@kernel.org>2018-11-01 18:00:01 +0100
committerArnaldo Carvalho de Melo <acme@redhat.com>2018-11-19 12:12:26 -0800
commitb01c1f69c8660eaeab7d365cd570103c5c073a02 (patch)
treee1ab044702056dbba650751977fae990e60e4a0b /tools/perf/util/namespaces.h
parenttools build feature: Check if get_current_dir_name() is available (diff)
perf tools: Restore proper cwd on return from mnt namespace
When reporting on 'record' server we try to retrieve/use the mnt namespace of the profiled tasks. We use following API with cookie to hold the return namespace, roughly: nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc) setns(newns, 0); ... new ns related open.. ... nsinfo__mountns_exit(struct nscookie *nc) setns(nc->oldns) Once finished we setns to old namespace, which also sets the current working directory (cwd) to "/", trashing the cwd we had. This is mostly fine, because we use absolute paths almost everywhere, but it screws up 'perf diff': # perf diff failed to open perf.data: No such file or directory (try 'perf record' first) ... Adding the current working directory to be part of the cookie and restoring it in the nsinfo__mountns_exit call. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Krister Johansen <kjlx@templeofstupid.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Fixes: 843ff37bb59e ("perf symbols: Find symbols in different mount namespace") Link: http://lkml.kernel.org/r/20181101170001.30019-1-jolsa@kernel.org [ No need to check for NULL args for free(), use zfree() for struct members ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/namespaces.h')
1 files changed, 1 insertions, 0 deletions
diff --git a/tools/perf/util/namespaces.h b/tools/perf/util/namespaces.h
index cae1a9a39722..d5f46c09ea31 100644
--- a/tools/perf/util/namespaces.h
+++ b/tools/perf/util/namespaces.h
@@ -38,6 +38,7 @@ struct nsinfo {
struct nscookie {
int oldns;
int newns;
+ char *oldcwd;
int nsinfo__init(struct nsinfo *nsi);