top: add config option and code for global CPU % display

This commit is contained in:
Denis Vlasenko 2007-06-10 17:11:59 +00:00
parent e8a0788b24
commit 5a65447e30
4 changed files with 70 additions and 20 deletions

View File

@ -43,6 +43,16 @@ takes 55k of memory on 64-bit x86 kernel.
On 32-bit kernel we need ~26k per applet.
Script:
i=1000; while test $i != 0; do
echo -n .
busybox sleep 30 &
i=$((i - 1))
done
echo
wait
(Data from NOMMU arches are sought. Provide 'size busybox' output too)

View File

@ -79,8 +79,15 @@ const char* get_cached_groupname(gid_t gid)
static int read_to_buf(const char *filename, void *buf)
{
ssize_t ret;
ret = open_read_close(filename, buf, PROCPS_BUFSIZE-1);
int fd;
/* open_read_close() would do two reads, checking for EOF.
* When you have 10000 /proc/$NUM/stat to read, it isn't desirable */
ssize_t ret = -1;
fd = open(filename, O_RDONLY);
if (fd >= 0) {
ret = read(fd, buf, PROCPS_BUFSIZE-1);
close(fd);
}
((char *)buf)[ret > 0 ? ret : 0] = '\0';
return ret;
}

View File

@ -102,11 +102,18 @@ config TOP
system.
config FEATURE_TOP_CPU_USAGE_PERCENTAGE
bool "Support showing CPU usage percentage (add 2k bytes)"
bool "Show CPU per-process usage percentage (adds 2k bytes)"
default y
depends on TOP
help
Make top display CPU usage.
Make top display CPU usage for each process.
config FEATURE_TOP_CPU_GLOBAL_PERCENTS
bool "Show CPU global usage percentage (adds 1k byte)"
default y
depends on FEATURE_TOP_CPU_USAGE_PERCENTAGE
help
Makes top display "CPU: n.n% us n.n% sy n.n% ni..." line.
config UPTIME
bool "uptime"

View File

@ -221,7 +221,6 @@ static unsigned long display_generic(int scr_width)
char scrbuf[80];
char *end;
unsigned long total, used, mfree, shared, buffers, cached;
unsigned int needs_conversion = 1;
/* read memory info */
fp = xfopen("meminfo", "r");
@ -241,13 +240,19 @@ static unsigned long display_generic(int scr_width)
fscanf(fp, "Mem: %lu %lu %lu %lu %lu %lu",
&total, &used, &mfree, &shared, &buffers, &cached);
/* convert to kilobytes */
used /= 1024;
mfree /= 1024;
shared /= 1024;
buffers /= 1024;
cached /= 1024;
total /= 1024;
} else {
/*
* Revert to manual parsing, which incidentally already has the
* sizes in kilobytes. This should be safe for both 2.4 and
* 2.6.
*/
needs_conversion = 0;
fscanf(fp, "MemFree: %lu %s\n", &mfree, buf);
@ -273,16 +278,6 @@ static unsigned long display_generic(int scr_width)
if (end) end = strchr(end+1, ' ');
if (end) *end = '\0';
if (needs_conversion) {
/* convert to kilobytes */
used /= 1024;
mfree /= 1024;
shared /= 1024;
buffers /= 1024;
cached /= 1024;
total /= 1024;
}
/* output memory info and load average */
/* clear screen & go to top */
if (scr_width > sizeof(scrbuf))
@ -293,8 +288,39 @@ static unsigned long display_generic(int scr_width)
printf(OPT_BATCH_MODE ? "%s\n" : "\e[H\e[J%s\n", scrbuf);
if (ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS) {
/*
* xxx% = (jif.xxx - prev_jif.xxx) / (jif.total - prev_jif.total) * 100%
*/
#define CALC_STAT(xxx) div_t xxx = div(1000 * (jif.xxx - prev_jif.xxx) / total_diff, 10)
#define SHOW_STAT(xxx) xxx.quot, '0'+xxx.rem
unsigned total_diff = (jif.total - prev_jif.total ? : 1);
CALC_STAT(usr);
CALC_STAT(sys);
CALC_STAT(nic);
CALC_STAT(idle);
CALC_STAT(iowait);
CALC_STAT(irq);
CALC_STAT(softirq);
//CALC_STAT(steal);
snprintf(scrbuf, scr_width,
/* %3u.%c in practice almost never displays "100.0"
* and thus has implicit leading space: " 99.6" */
"CPU:%3u.%c%% us%3u.%c%% sy%3u.%c%% ni%3u.%c%% id%3u.%c%% wa%3u.%c%% hi%3u.%c%% si",
// %3u.%c%%st", - what is this 'steal' thing?
// I doubt anyone needs to know it
SHOW_STAT(usr), SHOW_STAT(sys), SHOW_STAT(nic), SHOW_STAT(idle),
SHOW_STAT(iowait), SHOW_STAT(irq), SHOW_STAT(softirq)
//, SHOW_STAT(steal)
);
puts(scrbuf);
#undef SHOW_STAT
#undef CALC_STAT
}
snprintf(scrbuf, scr_width, "Load average: %s", buf);
printf("%s\n", scrbuf);
puts(scrbuf);
return total;
}
@ -479,7 +505,7 @@ int top_main(int argc, char **argv)
procps_status_t *p = NULL;
/* Default to 25 lines - 5 lines for status */
lines = 24 - 3;
lines = 24 - 3 USE_FEATURE_TOP_CPU_GLOBAL_PERCENTS( - 1);
col = 79;
#if ENABLE_FEATURE_USE_TERMIOS
get_terminal_width_height(0, &col, &lines);
@ -487,7 +513,7 @@ int top_main(int argc, char **argv)
sleep(interval);
continue;
}
lines -= 3;
lines -= 3 USE_FEATURE_TOP_CPU_GLOBAL_PERCENTS( + 1);
#endif /* FEATURE_USE_TERMIOS */
/* read process IDs & status for all the processes */