fix firemon, speed-up

1 files changed, 18 insertions, 10 deletions

diff --git a/src/lib/pid.c b/src/lib/pid.c
index ad6403f65..3cf0df909 100644
--- a/src/lib/pid.c
+++ b/src/lib/pid.c
@@ -30,7 +30,7 @@
 #define PIDS_BUFLEN 4096
 //Process pids[max_pids];
 Process *pids = NULL;
-int max_pids=32769;
+int max_pids=32769; // recalculated for every read_pid() call
 
 // get the memory associated with this pid
 void pid_getmem(unsigned pid, unsigned *rss, unsigned *shared) {
@@ -303,20 +303,22 @@ void pid_store_cpu(unsigned index, unsigned parent, unsigned *utime, unsigned *s
 
 // mon_pid: pid of sandbox to be monitored, 0 if all sandboxes are included
 void pid_read(pid_t mon_pid) {
-        if (pids == NULL) {
-                FILE *fp = fopen("/proc/sys/kernel/pid_max", "r");
-                if (fp) {
-                        int val;
-                        if (fscanf(fp, "%d", &val) == 1) {
-                                if (val >= max_pids)
-                                        max_pids = val + 1;
-                        }
-                        fclose(fp);
+        FILE *fp = fopen("/proc/sys/kernel/pid_max", "r");
+        if (fp) {
+                int val;
+                if (fscanf(fp, "%d", &val) == 1) {
+                        if (val >= max_pids)
+                                max_pids = val + 1;
                 }
+                fclose(fp);
+        }
+
+        if (pids == NULL) {
                 pids = malloc(sizeof(Process) * max_pids);
                 if (pids == NULL)
                         errExit("malloc");
         }
+
         memset(pids, 0, sizeof(Process) * max_pids);
         pid_t mypid = getpid();
 
@@ -332,9 +334,12 @@ void pid_read(pid_t mon_pid) {
 
         struct dirent *entry;
         char *end;
+        pid_t new_max_pids = 0;
         while ((entry = readdir(dir))) {
                 pid_t pid = strtol(entry->d_name, &end, 10);
                 pid %= max_pids;
+                if (pid > new_max_pids)
+                        new_max_pids = pid;
                 if (end == entry->d_name || *end)
                         continue;
                 if (pid == mypid)
@@ -418,6 +423,9 @@ void pid_read(pid_t mon_pid) {
         }
         closedir(dir);
 
+        // update max_pid
+        max_pids = new_max_pids;
+
         pid_t pid;
         for (pid = 0; pid < max_pids; pid++) {
                 int parent = pids[pid].parent;