lsfd: optimize -i/--inet option

The original code filters sockets in convert() stage.
This code adds weak-filtering in collect_processes() stage to improve
the performe.

Without this optimization:

    # time ./lsfd --json -i > /tmp/lsfd.txt
    0.43user 0.57system 0:01.02elapsed 99%CPU (0avgtext+0avgdata 52724maxresident)k
    0inputs+0outputs (0major+14263minor)pagefaults 0swaps

With this optimization:

    # time ./lsfd --json -i > /tmp/lsfd-i.txt
    0.08user 0.27system 0:00.36elapsed 98%CPU (0avgtext+0avgdata 7060maxresident)k
    0inputs+0outputs (0major+2831minor)pagefaults 0swaps

About three times faster.

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

diff --git a/misc-utils/lsfd.c b/misc-utils/lsfd.c
index cfc1948b5c35411ff088ef4d348ed4147a544862..40fcc5218220736d7c61766e4cf94f8ecbdddda3 100644 (file)
--- a/misc-utils/lsfd.c
+++ b/misc-utils/lsfd.c
@@ -365,7 +365,8 @@ struct lsfd_control {
                        notrunc : 1,
                        threads : 1,
                        show_main : 1,          /* print main table */
-                       show_summary : 1;       /* print summary/counters */
+                       show_summary : 1,       /* print summary/counters */
+                       sockets_only : 1;       /* display only SOCKETS */
 
        struct lsfd_filter *filter;
        struct lsfd_counter **counters;         /* NULL terminated array. */
@@ -636,7 +637,8 @@ static void read_fdinfo(struct file *file, FILE *fdinfo)
 static struct file *collect_file_symlink(struct path_cxt *pc,
                                         struct proc *proc,
                                         const char *name,
-                                        int assoc)
+                                        int assoc,
+                                        bool sockets_only)
 {
        char sym[PATH_MAX] = { '\0' };
        struct stat sb;
@@ -654,10 +656,20 @@ static struct file *collect_file_symlink(struct path_cxt *pc,
                f = copy_file(prev);
                f->association = assoc;
        } else {
+               const struct file_class *class;
+
                if (ul_path_stat(pc, &sb, 0, name) < 0)
                        return NULL;
 
-               f = new_file(proc, stat2class(&sb));
+               class = stat2class(&sb);
+               if (sockets_only
+                   /* A nsfs is not a socket but the nsfs can be used to
+                    * collect information from other network namespaces.
+                    * Besed on the information, various columns of sockets.
+                    */
+                   && (class != &sock_class)&& (class != &nsfs_file_class))
+                       return NULL;
+               f = new_file(proc, class);
                file_set_path(f, &sb, sym, assoc);
        }
 
@@ -690,7 +702,8 @@ static struct file *collect_file_symlink(struct path_cxt *pc,
 
 /* read symlinks from /proc/#/fd
  */
-static void collect_fd_files(struct path_cxt *pc, struct proc *proc)
+static void collect_fd_files(struct path_cxt *pc, struct proc *proc,
+                            bool sockets_only)
 {
        DIR *sub = NULL;
        struct dirent *d = NULL;
@@ -703,7 +716,7 @@ static void collect_fd_files(struct path_cxt *pc, struct proc *proc)
                        continue;
 
                snprintf(path, sizeof(path), "fd/%ju", (uintmax_t) num);
-               collect_file_symlink(pc, proc, path, num);
+               collect_file_symlink(pc, proc, path, num, sockets_only);
        }
 }
 
@@ -809,31 +822,37 @@ static void collect_outofbox_files(struct path_cxt *pc,
                                   struct proc *proc,
                                   enum association assocs[],
                                   const char *names[],
-                                  size_t count)
+                                  size_t count,
+                                  bool sockets_only)
 {
        size_t i;
 
        for (i = 0; i < count; i++)
-               collect_file_symlink(pc, proc, names[assocs[i]], assocs[i] * -1);
+               collect_file_symlink(pc, proc, names[assocs[i]], assocs[i] * -1,
+                                    sockets_only);
 }
 
-static void collect_execve_file(struct path_cxt *pc, struct proc *proc)
+static void collect_execve_file(struct path_cxt *pc, struct proc *proc,
+                               bool sockets_only)
 {
        enum association assocs[] = { ASSOC_EXE };
        const char *names[] = {
                [ASSOC_EXE]  = "exe",
        };
-       collect_outofbox_files(pc, proc, assocs, names, ARRAY_SIZE(assocs));
+       collect_outofbox_files(pc, proc, assocs, names, ARRAY_SIZE(assocs),
+                              sockets_only);
 }
 
-static void collect_fs_files(struct path_cxt *pc, struct proc *proc)
+static void collect_fs_files(struct path_cxt *pc, struct proc *proc,
+                            bool sockets_only)
 {
        enum association assocs[] = { ASSOC_EXE, ASSOC_CWD, ASSOC_ROOT };
        const char *names[] = {
                [ASSOC_CWD]  = "cwd",
                [ASSOC_ROOT] = "root",
        };
-       collect_outofbox_files(pc, proc, assocs, names, ARRAY_SIZE(assocs));
+       collect_outofbox_files(pc, proc, assocs, names, ARRAY_SIZE(assocs),
+                              sockets_only);
 }
 
 static void collect_namespace_files(struct path_cxt *pc, struct proc *proc)
@@ -862,7 +881,9 @@ static void collect_namespace_files(struct path_cxt *pc, struct proc *proc)
                [ASSOC_NS_USER]   = "ns/user",
                [ASSOC_NS_UTS]    = "ns/uts",
        };
-       collect_outofbox_files(pc, proc, assocs, names, ARRAY_SIZE(assocs));
+       collect_outofbox_files(pc, proc, assocs, names, ARRAY_SIZE(assocs),
+                              /* Namespace information is alwasys needed. */
+                              false);
 }
 
 static struct nodev *new_nodev(unsigned long minor, const char *filesystem)
@@ -1303,11 +1324,11 @@ static void read_process(struct lsfd_control *ctl, struct path_cxt *pc,
                free(pat);
        }
 
-       collect_execve_file(pc, proc);
+       collect_execve_file(pc, proc, ctl->sockets_only);
 
        if (proc->pid == proc->leader->pid
            || kcmp(proc->leader->pid, proc->pid, KCMP_FS, 0, 0) != 0)
-               collect_fs_files(pc, proc);
+               collect_fs_files(pc, proc, ctl->sockets_only);
 
        if (proc->ns_mnt == 0 || !has_mnt_ns(proc->ns_mnt)) {
                FILE *mnt = ul_path_fopen(pc, "r", "mountinfo");
@@ -1326,13 +1347,14 @@ static void read_process(struct lsfd_control *ctl, struct path_cxt *pc,
         * 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)
+       if ((!ctl->sockets_only)
+           && (proc->pid == proc->leader->pid
+               || kcmp(proc->leader->pid, proc->pid, KCMP_VM, 0, 0) != 0))
                collect_mem_files(pc, proc);
 
        if (proc->pid == proc->leader->pid
            || kcmp(proc->leader->pid, proc->pid, KCMP_FILES, 0, 0) != 0)
-               collect_fd_files(pc, proc);
+               collect_fd_files(pc, proc, ctl->sockets_only);
 
        list_add_tail(&proc->procs, &ctl->procs);
        if (tsearch(proc, &proc_tree, proc_tree_compare) == NULL)
@@ -1797,6 +1819,8 @@ int main(int argc, char *argv[])
                        break;
                case 'i': {
                        const char *subexpr = NULL;
+
+                       ctl.sockets_only = 1;
                        if (optarg == NULL)
                                subexpr = inet46_subexpr;
                        else if (strcmp(optarg, "4") == 0)