pidstat: Add option -R to display priority and policy information

Processes' scheduling priority and policy information are no longer
displayed with context switches stats. Create a dedicated report
instead, which can be displayed using pidstat's new option -R.

Signed-off-by: Sebastien GODARD <[email protected]>

pidstat.c

@@ -87,8 +87,8 @@ void usage(char *progname)
  progname);
 
  fprintf(stderr, _("Options are:\n"
- "[ -d ] [ -h ] [ -I ] [ -l ] [ -r ] [ -s ] [ -t ] [ -U [ <username> ] ] [ -u ]\n"
- "[ -V ] [ -v ] [ -w ] [ -C <command> ] [ -G <process_name> ]\n"
+ "[ -d ] [ -h ] [ -I ] [ -l ] [ -R ] [ -r ] [ -s ] [ -t ] [ -U [ <username> ] ]\n"
+ "[ -u ] [ -V ] [ -v ] [ -w ] [ -C <command> ] [ -G <process_name> ]\n"
  "[ -p { <pid> [,...] | SELF | ALL } ] [ -T { TASK | CHILD | ALL } ]\n"));
  exit(1);
 }
@@ -205,7 +205,8 @@ void check_flags(void)
 
  /* Check that requested activities are available */
  if (DISPLAY_TASK_STATS(tskflag)) {
- act |= P_A_CPU + P_A_MEM + P_A_IO + P_A_CTXSW + P_A_STACK + P_A_KTAB;
+ act |= P_A_CPU + P_A_MEM + P_A_IO + P_A_CTXSW
+ + P_A_STACK + P_A_KTAB + P_A_RT;
  }
  if (DISPLAY_CHILD_STATS(tskflag)) {
  act |= P_A_CPU + P_A_MEM;
@@ -1103,8 +1104,13 @@ int get_pid_to_display(int prev, int curr, int p, unsigned int activity,
 
  if (DISPLAY_CTXSW(activity) && (!isActive)) {
  if (((*pstc)->nvcsw != (*pstp)->nvcsw) ||
- ((*pstc)->nivcsw != (*pstp)->nivcsw) ||
- ((*pstc)->priority != (*pstp)->priority) ||
+ ((*pstc)->nivcsw != (*pstp)->nivcsw)) {
+ isActive = TRUE;
+ }
+ }
+
+ if (DISPLAY_RT(activity) && (!isActive)) {
+ if (((*pstc)->priority != (*pstp)->priority) ||
  ((*pstc)->policy != (*pstp)->policy)) {
  isActive = TRUE;
  }
@@ -1291,11 +1297,14 @@ int write_pid_task_all_stats(int prev, int curr, int dis,
  printf(" kB_rd/s kB_wr/s kB_ccwr/s iodelay");
  }
  if (DISPLAY_CTXSW(actflag)) {
- printf(" cswch/s nvcswch/s prio policy");
+ printf(" cswch/s nvcswch/s");
  }
  if (DISPLAY_KTAB(actflag)) {
  printf(" threads fd-nr");
  }
+ if (DISPLAY_RT(actflag)) {
+ printf(" prio policy");
+ }
  printf(" Command\n");
  }
 
@@ -1362,11 +1371,9 @@ int write_pid_task_all_stats(int prev, int curr, int dis,
  }
 
  if (DISPLAY_CTXSW(actflag)) {
- printf(" %9.2f %9.2f %4u %6s",
+ printf(" %9.2f %9.2f",
  S_VALUE(pstp->nvcsw, pstc->nvcsw, itv),
- S_VALUE(pstp->nivcsw, pstc->nivcsw, itv),
- pstc->priority,
- PRINT_POLICY(pstc->policy));
+ S_VALUE(pstp->nivcsw, pstc->nivcsw, itv));
  }
 
  if (DISPLAY_KTAB(actflag)) {
@@ -1380,6 +1387,12 @@ int write_pid_task_all_stats(int prev, int curr, int dis,
  }
  }
 
+ if (DISPLAY_RT(actflag)) {
+ printf(" %4u %6s",
+ pstc->priority,
+ GET_POLICY(pstc->policy));
+ }
+
  print_comm(pstc);
  again = 1;
  }
@@ -1946,7 +1959,7 @@ int write_pid_ctxswitch_stats(int prev, int curr, int dis,
 
  if (dis) {
  PRINT_ID_HDR(prev_string, pidflag);
- printf(" cswch/s nvcswch/s prio policy  Command\n");
+ printf(" cswch/s nvcswch/s Command\n");
  }
 
  for (p = 0; p < pid_nr; p++) {
@@ -1956,11 +1969,60 @@ int write_pid_ctxswitch_stats(int prev, int curr, int dis,
  continue;
 
  print_line_id(curr_string, pstc);
- printf(" %9.2f %9.2f %4u %6s",
+ printf(" %9.2f %9.2f",
  S_VALUE(pstp->nvcsw, pstc->nvcsw, itv),
- S_VALUE(pstp->nivcsw, pstc->nivcsw, itv),
+ S_VALUE(pstp->nivcsw, pstc->nivcsw, itv));
+ print_comm(pstc);
+ again = 1;
+ }
+
+ return again;
+}
+
+/*
+ ***************************************************************************
+ * Display scheduling priority and policy information.
+ *
+ * IN:
+ * @prev Index in array where stats used as reference are.
+ * @curr Index in array for current sample statistics.
+ * @dis TRUE if a header line must be printed.
+ * @prev_string String displayed at the beginning of a header line. This is
+ * the timestamp of the previous sample, or "Average" when
+ * displaying average stats.
+ * @curr_string String displayed at the beginning of current sample stats.
+ * This is the timestamp of the current sample, or "Average"
+ * when displaying average stats.
+ * @itv Interval of time in jiffies.
+ *
+ * RETURNS:
+ * 0 if all the processes to display have terminated.
+ * <> 0 if there are still some processes left to display.
+ ***************************************************************************
+ */
+int write_pid_rt_stats(int prev, int curr, int dis,
+ char *prev_string, char *curr_string,
+ unsigned long long itv)
+{
+ struct pid_stats *pstc, *pstp;
+ unsigned int p;
+ int again = 0;
+
+ if (dis) {
+ PRINT_ID_HDR(prev_string, pidflag);
+ printf(" prio policy Command\n");
+ }
+
+ for (p = 0; p < pid_nr; p++) {
+
+ if (get_pid_to_display(prev, curr, p, P_A_RT, P_NULL,
+ &pstc, &pstp) <= 0)
+ continue;
+
+ print_line_id(curr_string, pstc);
+ printf(" %4u %6s",
  pstc->priority,
- PRINT_POLICY(pstc->policy));
+ GET_POLICY(pstc->policy));
  print_comm(pstc);
  again = 1;
  }
@@ -2154,6 +2216,12 @@ int write_stats_core(int prev, int curr, int dis, int disp_avg,
  again += write_pid_ktab_stats(prev, curr, dis, disp_avg,
  prev_string, curr_string, itv);
  }
+
+ /* Display scheduling priority and policy information */
+ if (DISPLAY_RT(actflag)) {
+ again += write_pid_rt_stats(prev, curr, dis, prev_string,
+ curr_string, itv);
+ }
  }
 
  if (DISPLAY_ALL_PID(pidflag)) {
@@ -2492,6 +2560,12 @@ int main(int argc, char **argv)
  pidflag |= P_D_CMDLINE;
  break;
 
+ case 'R':
+ /* Display priority and policy info */
+ actflag |= P_A_RT;
+ dis_hdr++;
+ break;
+
  case 'r':
  /* Display memory usage */
  actflag |= P_A_MEM;

pidstat.h

@@ -26,13 +26,15 @@
 #define P_A_CTXSW 0x08
 #define P_A_STACK 0x10
 #define P_A_KTAB 0x20
+#define P_A_RT 0x40
 
 #define DISPLAY_CPU(m) (((m) & P_A_CPU) == P_A_CPU)
 #define DISPLAY_MEM(m) (((m) & P_A_MEM) == P_A_MEM)
 #define DISPLAY_IO(m) (((m) & P_A_IO) == P_A_IO)
 #define DISPLAY_CTXSW(m) (((m) & P_A_CTXSW) == P_A_CTXSW)
 #define DISPLAY_STACK(m) (((m) & P_A_STACK) == P_A_STACK)
 #define DISPLAY_KTAB(m) (((m) & P_A_KTAB) == P_A_KTAB)
+#define DISPLAY_RT(m) (((m) & P_A_RT) == P_A_RT)
 
 /* TASK/CHILD */
 #define P_NULL 0x00
@@ -107,7 +109,7 @@
  } \
  } while (0)
 
-#define PRINT_POLICY(p) \
+#define GET_POLICY(p) \
  (p == SCHED_NORMAL ? "NORMAL" : \
  (p == SCHED_FIFO ? "FIFO" : \
  (p == SCHED_RR ? "RR" : \