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[S390] dasd: improve dasd statistics proc interface
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For a large number of I/O requests the values were shifted binary.
The shift was not transparent for the user because the shift value
was not displayed. To make this interface more human readable the
values are shifted decimal and the scale factor is displayed.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Stefan Haberland authored and Martin Schwidefsky committed Dec 25, 2008
1 parent bd43a42 commit 2bf373b
Showing 1 changed file with 15 additions and 13 deletions.
28 changes: 15 additions & 13 deletions drivers/s390/block/dasd_proc.c
Original file line number Diff line number Diff line change
Expand Up @@ -180,12 +180,12 @@ dasd_calc_metrics(char *page, char **start, off_t off,

#ifdef CONFIG_DASD_PROFILE
static char *
dasd_statistics_array(char *str, unsigned int *array, int shift)
dasd_statistics_array(char *str, unsigned int *array, int factor)
{
int i;

for (i = 0; i < 32; i++) {
str += sprintf(str, "%7d ", array[i] >> shift);
str += sprintf(str, "%7d ", array[i] / factor);
if (i == 15)
str += sprintf(str, "\n");
}
Expand All @@ -202,7 +202,7 @@ dasd_statistics_read(char *page, char **start, off_t off,
#ifdef CONFIG_DASD_PROFILE
struct dasd_profile_info_t *prof;
char *str;
int shift;
int factor;

/* check for active profiling */
if (dasd_profile_level == DASD_PROFILE_OFF) {
Expand All @@ -214,12 +214,14 @@ dasd_statistics_read(char *page, char **start, off_t off,

prof = &dasd_global_profile;
/* prevent couter 'overflow' on output */
for (shift = 0; (prof->dasd_io_reqs >> shift) > 9999999; shift++);
for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
factor *= 10);

str = page;
str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
str += sprintf(str, "with %d sectors(512B each)\n",
str += sprintf(str, "with %u sectors(512B each)\n",
prof->dasd_io_sects);
str += sprintf(str, "Scale Factor is %d\n", factor);
str += sprintf(str,
" __<4 ___8 __16 __32 __64 _128 "
" _256 _512 __1k __2k __4k __8k "
Expand All @@ -230,22 +232,22 @@ dasd_statistics_read(char *page, char **start, off_t off,
" __1G __2G __4G " " _>4G\n");

str += sprintf(str, "Histogram of sizes (512B secs)\n");
str = dasd_statistics_array(str, prof->dasd_io_secs, shift);
str = dasd_statistics_array(str, prof->dasd_io_secs, factor);
str += sprintf(str, "Histogram of I/O times (microseconds)\n");
str = dasd_statistics_array(str, prof->dasd_io_times, shift);
str = dasd_statistics_array(str, prof->dasd_io_times, factor);
str += sprintf(str, "Histogram of I/O times per sector\n");
str = dasd_statistics_array(str, prof->dasd_io_timps, shift);
str = dasd_statistics_array(str, prof->dasd_io_timps, factor);
str += sprintf(str, "Histogram of I/O time till ssch\n");
str = dasd_statistics_array(str, prof->dasd_io_time1, shift);
str = dasd_statistics_array(str, prof->dasd_io_time1, factor);
str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
str = dasd_statistics_array(str, prof->dasd_io_time2, shift);
str = dasd_statistics_array(str, prof->dasd_io_time2, factor);
str += sprintf(str, "Histogram of I/O time between ssch "
"and irq per sector\n");
str = dasd_statistics_array(str, prof->dasd_io_time2ps, shift);
str = dasd_statistics_array(str, prof->dasd_io_time2ps, factor);
str += sprintf(str, "Histogram of I/O time between irq and end\n");
str = dasd_statistics_array(str, prof->dasd_io_time3, shift);
str = dasd_statistics_array(str, prof->dasd_io_time3, factor);
str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
str = dasd_statistics_array(str, prof->dasd_io_nr_req, shift);
str = dasd_statistics_array(str, prof->dasd_io_nr_req, factor);
len = str - page;
#else
len = sprintf(page, "Statistics are not activated in this kernel\n");
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