delayacct: improve the average delay precision of getdelay tool to microsecond

Improve the average delay precision of getdelay tool to microsecond.  When
using the getdelay tool, it is sometimes found that the average delay
except CPU is not 0, but display is 0, because the precison is too low.
For example, see delay average of SWAP below when using ZRAM.

print delayacct stats ON
PID	32915
CPU             count     real total  virtual total    delay total  delay average
               339202     2793871936     9233585504        7951112          0.000ms
IO              count    delay total  delay average
                   41      419296904             10ms
SWAP            count    delay total  delay average
               242589     1045792384              0ms

This wrong display is misleading, so improve the millisecond precision of
the average delay to microsecond just like CPU.  Then user would get more
accurate information of delay time.

Link: https://lkml.kernel.org/r/202302131408087983857@zte.com.cn
Signed-off-by: Wang Yong <wang.yong12@zte.com.cn>
Reviewed-by: Yang Yang <yang.yang29@zte.com.cn>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/Documentation/accounting/delay-accounting.rst b/Documentation/accounting/delay-accounting.rst
index 7103b62ba6d7eaa1359abcdef3c2e15ee5356d86..79f537c9f160b35b6cd83b1f9843318e2382c24f 100644 (file)
--- a/Documentation/accounting/delay-accounting.rst
+++ b/Documentation/accounting/delay-accounting.rst
@@ -109,17 +109,17 @@ Get sum of delays, since system boot, for all pids with tgid 5::
        CPU             count     real total  virtual total    delay total  delay average
                            8        7000000        6872122        3382277          0.423ms
        IO              count    delay total  delay average
-                           0              0              0ms
+                   0              0          0.000ms
        SWAP            count    delay total  delay average
-                           0              0              0ms
+                       0              0          0.000ms
        RECLAIM         count    delay total  delay average
-                           0              0              0ms
+                   0              0          0.000ms
        THRASHING       count    delay total  delay average
-                           0              0              0ms
+                       0              0          0.000ms
        COMPACT         count    delay total  delay average
-                           0              0              0ms
-        WPCOPY          count    delay total  delay average
-                            0              0              0ms
+                       0              0          0.000ms
+   WPCOPY          count    delay total  delay average
+                       0              0          0.000ms
 
 Get IO accounting for pid 1, it works only with -p::
 

diff --git a/Documentation/translations/zh_CN/accounting/delay-accounting.rst b/Documentation/translations/zh_CN/accounting/delay-accounting.rst
index a01dc3d5b0dbb7d5d983db2c426640b8b4c81c7e..7b8693ccf80a909c66f5531ce87bbd49de812357 100644 (file)
--- a/Documentation/translations/zh_CN/accounting/delay-accounting.rst
+++ b/Documentation/translations/zh_CN/accounting/delay-accounting.rst
@@ -92,15 +92,15 @@ getdelays命令的一般格式::
        CPU             count     real total  virtual total    delay total  delay average
                            8        7000000        6872122        3382277          0.423ms
        IO              count    delay total  delay average
-                           0              0              0ms
+                           0              0              0.000ms
        SWAP            count    delay total  delay average
-                           0              0              0ms
+                           0              0              0.000ms
        RECLAIM         count    delay total  delay average
-                           0              0              0ms
+                           0              0              0.000ms
        THRASHING       count    delay total  delay average
-                           0              0              0ms
+                           0              0              0.000ms
        COMPACT         count    delay total  delay average
-                           0              0              0ms
+                           0              0              0.000ms
     WPCOPY          count    delay total  delay average
                        0              0              0ms
 

diff --git a/tools/accounting/getdelays.c b/tools/accounting/getdelays.c
index 938dec0dfaad844caf823024812c8e79b9c81a2f..23a15d8f2bf4f4e4b4528204a563125f155585bb 100644 (file)
--- a/tools/accounting/getdelays.c
+++ b/tools/accounting/getdelays.c
@@ -198,17 +198,17 @@ static void print_delayacct(struct taskstats *t)
        printf("\n\nCPU   %15s%15s%15s%15s%15s\n"
               "      %15llu%15llu%15llu%15llu%15.3fms\n"
               "IO    %15s%15s%15s\n"
-              "      %15llu%15llu%15llums\n"
+          "      %15llu%15llu%15.3fms\n"
               "SWAP  %15s%15s%15s\n"
-              "      %15llu%15llu%15llums\n"
+          "      %15llu%15llu%15.3fms\n"
               "RECLAIM  %12s%15s%15s\n"
-              "      %15llu%15llu%15llums\n"
+          "      %15llu%15llu%15.3fms\n"
               "THRASHING%12s%15s%15s\n"
-              "      %15llu%15llu%15llums\n"
+          "      %15llu%15llu%15.3fms\n"
               "COMPACT  %12s%15s%15s\n"
-              "      %15llu%15llu%15llums\n"
+          "      %15llu%15llu%15.3fms\n"
               "WPCOPY   %12s%15s%15s\n"
-              "      %15llu%15llu%15llums\n",
+          "      %15llu%15llu%15.3fms\n",
               "count", "real total", "virtual total",
               "delay total", "delay average",
               (unsigned long long)t->cpu_count,
@@ -219,27 +219,27 @@ static void print_delayacct(struct taskstats *t)
               "count", "delay total", "delay average",
               (unsigned long long)t->blkio_count,
               (unsigned long long)t->blkio_delay_total,
-              average_ms(t->blkio_delay_total, t->blkio_count),
+          average_ms((double)t->blkio_delay_total, t->blkio_count),
               "count", "delay total", "delay average",
               (unsigned long long)t->swapin_count,
               (unsigned long long)t->swapin_delay_total,
-              average_ms(t->swapin_delay_total, t->swapin_count),
+          average_ms((double)t->swapin_delay_total, t->swapin_count),
               "count", "delay total", "delay average",
               (unsigned long long)t->freepages_count,
               (unsigned long long)t->freepages_delay_total,
-              average_ms(t->freepages_delay_total, t->freepages_count),
+          average_ms((double)t->freepages_delay_total, t->freepages_count),
               "count", "delay total", "delay average",
               (unsigned long long)t->thrashing_count,
               (unsigned long long)t->thrashing_delay_total,
-              average_ms(t->thrashing_delay_total, t->thrashing_count),
+          average_ms((double)t->thrashing_delay_total, t->thrashing_count),
               "count", "delay total", "delay average",
               (unsigned long long)t->compact_count,
               (unsigned long long)t->compact_delay_total,
-              average_ms(t->compact_delay_total, t->compact_count),
+          average_ms((double)t->compact_delay_total, t->compact_count),
               "count", "delay total", "delay average",
               (unsigned long long)t->wpcopy_count,
               (unsigned long long)t->wpcopy_delay_total,
-              average_ms(t->wpcopy_delay_total, t->wpcopy_count));
+          average_ms((double)t->wpcopy_delay_total, t->wpcopy_count));
 }
 
 static void task_context_switch_counts(struct taskstats *t)