lsfd: don't collect and print redundant information about threads

Signed-off-by: Masatake YAMATO <yamato@redhat.com>

diff --git a/misc-utils/lsfd.c b/misc-utils/lsfd.c
index 23b980898bdcb006bebb69806901217036fd14ee..4f831c0ff5a190e59485b2e645cb464f40177e1f 100644 (file)
--- a/misc-utils/lsfd.c
+++ b/misc-utils/lsfd.c
@@ -30,6 +30,14 @@
 #include <unistd.h>
 #include <getopt.h>
 
+#include <sys/syscall.h>
+#include <linux/kcmp.h>
+static int kcmp(pid_t pid1, pid_t pid2, int type,
+               unsigned long idx1, unsigned long idx2)
+{
+       return syscall(SYS_kcmp, pid1, pid2, type, idx1, idx2);
+}
+
 #include "c.h"
 #include "nls.h"
 #include "xalloc.h"
@@ -459,13 +467,25 @@ static void collect_outofbox_files(struct proc *proc,
        closedir(dirp);
 }
 
-static void collect_execve_files(struct proc *proc)
+static void collect_execve_file(struct proc *proc)
 {
        const char *execve_template = "/proc/%d";
-       enum association execve_assocs[] = { ASSOC_CWD, ASSOC_EXE, ASSOC_ROOT };
+       enum association execve_assocs[] = { ASSOC_EXE };
+       const char* execve_assoc_names[] = {
+               [ASSOC_EXE]  = "exe",
+       };
+       collect_outofbox_files(proc, execve_template,
+                              execve_assocs, execve_assoc_names,
+                              ARRAY_SIZE(execve_assocs));
+}
+
+static void collect_execve_and_fs_files(struct proc *proc)
+{
+       const char *execve_template = "/proc/%d";
+       enum association execve_assocs[] = { ASSOC_EXE, ASSOC_CWD, ASSOC_ROOT };
        const char* execve_assoc_names[] = {
-               [ASSOC_CWD]  = "cwd",
                [ASSOC_EXE]  = "exe",
+               [ASSOC_CWD]  = "cwd",
                [ASSOC_ROOT] = "root",
        };
        collect_outofbox_files(proc, execve_template,
@@ -514,10 +534,30 @@ static void fill_proc(struct proc *proc)
        if (!proc->command)
                proc->command = xstrdup(_("(unknown)"));
 
-       collect_execve_files(proc);
+
+       if (proc->pid == proc->leader->pid
+           || kcmp(proc->leader->pid, proc->pid,
+                   KCMP_FS, 0, 0) != 0)
+               collect_execve_and_fs_files(proc);
+       else
+               collect_execve_file(proc);
+
        collect_namespace_files(proc);
-       collect_mem_files(proc);
-       collect_fd_files(proc);
+
+       /* If kcmp is not available,
+        * there is no way to no whether threads share resources.
+        * In such cases, we must pay the costs: call collect_mem_files()
+        * and collect_fd_files().
+        */
+       if (proc->pid == proc->leader->pid
+           || kcmp(proc->leader->pid, proc->pid,
+                   KCMP_VM, 0, 0) != 0)
+               collect_mem_files(proc);
+
+       if (proc->pid == proc->leader->pid
+           || kcmp(proc->leader->pid, proc->pid,
+                   KCMP_FILES, 0, 0) != 0)
+               collect_fd_files(proc);
 }
 
 static void *fill_procs(void *arg)

diff --git a/misc-utils/lsfd.h b/misc-utils/lsfd.h
index 3ee71a265f8b97030fd3de03c701694ada926bd9..72cd84bc1978f3a9d399a75c95588eab677fc5b5 100644 (file)
--- a/misc-utils/lsfd.h
+++ b/misc-utils/lsfd.h
@@ -73,8 +73,8 @@ enum {
  * Process structure
  */
 enum association {
-       ASSOC_CWD = 1,
-       ASSOC_EXE,
+       ASSOC_EXE = 1,
+       ASSOC_CWD,
        ASSOC_ROOT,
        ASSOC_NS_CGROUP,
        ASSOC_NS_IPC,