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author | Konstantin Khlebnikov <khlebnikov@yandex-team.ru> | 2017-02-08 14:28:55 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-02-10 16:02:26 +0100 |
commit | 17627157cda13089d8a6c1c2d35acb07334b899c (patch) | |
tree | 9a717bcda9657c2e46943d852631e0a53fe3e45a /include/trace | |
parent | 64e90a8acb8590c2468c919f803652f081e3a4bf (diff) | |
download | linux-17627157cda13089d8a6c1c2d35acb07334b899c.tar.gz linux-17627157cda13089d8a6c1c2d35acb07334b899c.tar.bz2 linux-17627157cda13089d8a6c1c2d35acb07334b899c.zip |
kernfs: handle null pointers while printing node name and path
Null kernfs nodes could be found at cgroups during construction.
It seems safer to handle these null pointers right in kernfs in
the same way as printf prints "(null)" for null pointer string.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/trace')
-rw-r--r-- | include/trace/events/cgroup.h | 20 |
1 files changed, 6 insertions, 14 deletions
diff --git a/include/trace/events/cgroup.h b/include/trace/events/cgroup.h index ab68640a18d0..c226f50e88fa 100644 --- a/include/trace/events/cgroup.h +++ b/include/trace/events/cgroup.h @@ -61,19 +61,15 @@ DECLARE_EVENT_CLASS(cgroup, __field( int, id ) __field( int, level ) __dynamic_array(char, path, - cgrp->kn ? cgroup_path(cgrp, NULL, 0) + 1 - : strlen("(null)")) + cgroup_path(cgrp, NULL, 0) + 1) ), TP_fast_assign( __entry->root = cgrp->root->hierarchy_id; __entry->id = cgrp->id; __entry->level = cgrp->level; - if (cgrp->kn) - cgroup_path(cgrp, __get_dynamic_array(path), - __get_dynamic_array_len(path)); - else - __assign_str(path, "(null)"); + cgroup_path(cgrp, __get_dynamic_array(path), + __get_dynamic_array_len(path)); ), TP_printk("root=%d id=%d level=%d path=%s", @@ -119,8 +115,7 @@ DECLARE_EVENT_CLASS(cgroup_migrate, __field( int, dst_id ) __field( int, dst_level ) __dynamic_array(char, dst_path, - dst_cgrp->kn ? cgroup_path(dst_cgrp, NULL, 0) + 1 - : strlen("(null)")) + cgroup_path(dst_cgrp, NULL, 0) + 1) __field( int, pid ) __string( comm, task->comm ) ), @@ -129,11 +124,8 @@ DECLARE_EVENT_CLASS(cgroup_migrate, __entry->dst_root = dst_cgrp->root->hierarchy_id; __entry->dst_id = dst_cgrp->id; __entry->dst_level = dst_cgrp->level; - if (dst_cgrp->kn) - cgroup_path(dst_cgrp, __get_dynamic_array(dst_path), - __get_dynamic_array_len(dst_path)); - else - __assign_str(dst_path, "(null)"); + cgroup_path(dst_cgrp, __get_dynamic_array(dst_path), + __get_dynamic_array_len(dst_path)); __entry->pid = task->pid; __assign_str(comm, task->comm); ), |