Mainly running scripts/Lindent, from kernel dir, to replace indent spaces by tabs. Cc: Yang Feng <philip.yang@xxxxxxxxxx> Cc: Christophe Varoqui <christophe.varoqui@xxxxxxxxxxx> Cc: device-mapper development <dm-devel@xxxxxxxxxx> Signed-off-by: Xose Vazquez Perez <xose.vazquez@xxxxxxxxx> --- libmultipath/prioritizers/path_latency.c | 354 +++++++++++++++---------------- 1 file changed, 177 insertions(+), 177 deletions(-) diff --git a/libmultipath/prioritizers/path_latency.c b/libmultipath/prioritizers/path_latency.c index 34b734b..9fc2dfc 100644 --- a/libmultipath/prioritizers/path_latency.c +++ b/libmultipath/prioritizers/path_latency.c @@ -17,8 +17,8 @@ * Author(s): Yang Feng <philip.yang@xxxxxxxxxx> * * This file is released under the GPL version 2, or any later version. - * */ + #include <stdio.h> #include <math.h> #include <ctype.h> @@ -31,27 +31,28 @@ #define pp_pl_log(prio, fmt, args...) condlog(prio, "path_latency prio: " fmt, ##args) -#define MAX_IO_NUM 200 -#define MIN_IO_NUM 2 +#define MAX_IO_NUM 200 +#define MIN_IO_NUM 2 -#define MAX_BASE_NUM 10 -#define MIN_BASE_NUM 2 +#define MAX_BASE_NUM 10 +#define MIN_BASE_NUM 2 -#define MAX_AVG_LATENCY 100000000. /*Unit: us*/ -#define MIN_AVG_LATENCY 1. /*Unit: us*/ +#define MAX_AVG_LATENCY 100000000. /* Unit: us */ +#define MIN_AVG_LATENCY 1. /* Unit: us */ -#define DEFAULT_PRIORITY 0 +#define DEFAULT_PRIORITY 0 -#define MAX_CHAR_SIZE 30 +#define MAX_CHAR_SIZE 30 -#define USEC_PER_SEC 1000000LL -#define NSEC_PER_USEC 1000LL +#define USEC_PER_SEC 1000000LL +#define NSEC_PER_USEC 1000LL static long long path_latency[MAX_IO_NUM]; static inline long long timeval_to_us(const struct timespec *tv) { - return ((long long) tv->tv_sec * USEC_PER_SEC) + (tv->tv_nsec / NSEC_PER_USEC); + return ((long long)tv->tv_sec * USEC_PER_SEC) + + (tv->tv_nsec / NSEC_PER_USEC); } static int do_readsector0(int fd, unsigned int timeout) @@ -60,198 +61,197 @@ static int do_readsector0(int fd, unsigned int timeout) unsigned char sbuf[SENSE_BUFF_LEN]; int ret; - ret = sg_read(fd, &buf[0], 4096, &sbuf[0], - SENSE_BUFF_LEN, timeout); + ret = sg_read(fd, &buf[0], 4096, &sbuf[0], SENSE_BUFF_LEN, timeout); return ret; } int check_args_valid(int io_num, int base_num) { - if ((io_num < MIN_IO_NUM) || (io_num > MAX_IO_NUM)) - { - pp_pl_log(0, "args io_num is outside the valid range"); - return 0; - } - - if ((base_num < MIN_BASE_NUM) || (base_num > MAX_BASE_NUM)) - { - pp_pl_log(0, "args base_num is outside the valid range"); - return 0; - } - - return 1; + if ((io_num < MIN_IO_NUM) || (io_num > MAX_IO_NUM)) { + pp_pl_log(0, "args io_num is outside the valid range"); + return 0; + } + + if ((base_num < MIN_BASE_NUM) || (base_num > MAX_BASE_NUM)) { + pp_pl_log(0, "args base_num is outside the valid range"); + return 0; + } + + return 1; } -/* In multipath.conf, args form: io_num|base_num. For example, -* args is "20|10", this function can get io_num value 20, and - base_num value 10. -*/ -static int get_ionum_and_basenum(char *args, - int *ionum, - int *basenum) +/* + * In multipath.conf, args form: io_num|base_num. For example, + * args is "20|10", this function can get io_num value 20, and + * base_num value 10. + */ +static int get_ionum_and_basenum(char *args, int *ionum, int *basenum) { - char source[MAX_CHAR_SIZE]; - char vertica = '|'; - char *endstrbefore = NULL; - char *endstrafter = NULL; - unsigned int size = strlen(args); - - if ((args == NULL) || (ionum == NULL) || (basenum == NULL)) - { - pp_pl_log(0, "args string is NULL"); - return 0; - } - - if ((size < 1) || (size > MAX_CHAR_SIZE-1)) - { - pp_pl_log(0, "args string's size is too long"); - return 0; - } - - memcpy(source, args, size+1); - - if (!isdigit(source[0])) - { - pp_pl_log(0, "invalid prio_args format: %s", source); - return 0; - } - - *ionum = (int)strtoul(source, &endstrbefore, 10); - if (endstrbefore[0] != vertica) - { - pp_pl_log(0, "invalid prio_args format: %s", source); - return 0; - } - - if (!isdigit(endstrbefore[1])) - { - pp_pl_log(0, "invalid prio_args format: %s", source); - return 0; - } - - *basenum = (long long)strtol(&endstrbefore[1], &endstrafter, 10); - if (check_args_valid(*ionum, *basenum) == 0) - { - return 0; - } - - return 1; + char source[MAX_CHAR_SIZE]; + char vertica = '|'; + char *endstrbefore = NULL; + char *endstrafter = NULL; + unsigned int size = strlen(args); + + if ((args == NULL) || (ionum == NULL) || (basenum == NULL)) { + pp_pl_log(0, "args string is NULL"); + return 0; + } + + if ((size < 1) || (size > MAX_CHAR_SIZE - 1)) { + pp_pl_log(0, "args string's size is too long"); + return 0; + } + + memcpy(source, args, size + 1); + + if (!isdigit(source[0])) { + pp_pl_log(0, "invalid prio_args format: %s", source); + return 0; + } + + *ionum = (int)strtoul(source, &endstrbefore, 10); + if (endstrbefore[0] != vertica) { + pp_pl_log(0, "invalid prio_args format: %s", source); + return 0; + } + + if (!isdigit(endstrbefore[1])) { + pp_pl_log(0, "invalid prio_args format: %s", source); + return 0; + } + + *basenum = (long long)strtol(&endstrbefore[1], &endstrafter, 10); + if (check_args_valid(*ionum, *basenum) == 0) { + return 0; + } + + return 1; } -long long calc_standard_deviation(long long *path_latency, int size, long long avglatency) +long long calc_standard_deviation(long long *path_latency, int size, + long long avglatency) { - int index; - long long total = 0; + int index; + long long total = 0; - for (index = 0; index < size; index++) - { - total += (path_latency[index] - avglatency) * (path_latency[index] - avglatency); - } + for (index = 0; index < size; index++) { + total += + (path_latency[index] - avglatency) * (path_latency[index] - + avglatency); + } - total /= (size-1); + total /= (size - 1); - return (long long)sqrt((double)total); + return (long long)sqrt((double)total); } -int calcPrio(double avglatency, double max_avglatency, double min_avglatency, double base_num) +int calcPrio(double avglatency, double max_avglatency, double min_avglatency, + double base_num) { - double lavglatency = log(avglatency)/log(base_num); - double lmax_avglatency = log(max_avglatency)/log(base_num); - double lmin_avglatency = log(min_avglatency)/log(base_num); + double lavglatency = log(avglatency) / log(base_num); + double lmax_avglatency = log(max_avglatency) / log(base_num); + double lmin_avglatency = log(min_avglatency) / log(base_num); - if (lavglatency <= lmin_avglatency) - return (int)(lmax_avglatency + 1.); + if (lavglatency <= lmin_avglatency) + return (int)(lmax_avglatency + 1.); - if (lavglatency > lmax_avglatency) - return 0; + if (lavglatency > lmax_avglatency) + return 0; - return (int)(lmax_avglatency - lavglatency + 1.); + return (int)(lmax_avglatency - lavglatency + 1.); } /* Calc the latency interval corresponding to the average latency */ long long calc_latency_interval(double avglatency, double max_avglatency, - double min_avglatency, double base_num) + double min_avglatency, double base_num) { - double lavglatency = log(avglatency)/log(base_num); - double lmax_avglatency = log(max_avglatency)/log(base_num); - double lmin_avglatency = log(min_avglatency)/log(base_num); - - if ((lavglatency <= lmin_avglatency) - || (lavglatency > lmax_avglatency)) - return 0;/* Invalid value */ - - if ((double)((int)lavglatency) == lavglatency) - return (long long)(avglatency - (avglatency / base_num)); - else - return (long long)(pow(base_num, (double)((int)lavglatency + 1)) - - pow(base_num, (double)((int)lavglatency))); + double lavglatency = log(avglatency) / log(base_num); + double lmax_avglatency = log(max_avglatency) / log(base_num); + double lmin_avglatency = log(min_avglatency) / log(base_num); + + if ((lavglatency <= lmin_avglatency) + || (lavglatency > lmax_avglatency)) + return 0; /* Invalid value */ + + if ((double)((int)lavglatency) == lavglatency) + return (long long)(avglatency - (avglatency / base_num)); + else + return (long long)(pow(base_num, (double)((int)lavglatency + 1)) + - pow(base_num, (double)((int)lavglatency))); } -int getprio (struct path *pp, char *args, unsigned int timeout) +int getprio(struct path *pp, char *args, unsigned int timeout) { - int rc, temp; - int index = 0; - int io_num; - int base_num; - long long avglatency; - long long latency_interval; - long long standard_deviation; - long long toldelay = 0; - long long before, after; - struct timespec tv; - - if (pp->fd < 0) - return -1; - - if (get_ionum_and_basenum(args, &io_num, &base_num) == 0) - { - pp_pl_log(0, "%s: get path_latency args fail", pp->dev); - return DEFAULT_PRIORITY; - } - - memset(path_latency, 0, sizeof(path_latency)); - - temp = io_num; - while (temp-- > 0) - { - (void)clock_gettime(CLOCK_MONOTONIC, &tv); - before = timeval_to_us(&tv); - - if (do_readsector0(pp->fd, timeout) == 2) - { - pp_pl_log(0, "%s: path down", pp->dev); - return -1; - } - - (void)clock_gettime(CLOCK_MONOTONIC, &tv); - after = timeval_to_us(&tv); - - path_latency[index] = after - before; - toldelay += path_latency[index++]; - } - - avglatency = toldelay/(long long)io_num; - pp_pl_log(4, "%s: average latency is (%lld us)", pp->dev, avglatency); - - if (avglatency > MAX_AVG_LATENCY) - { - pp_pl_log(0, "%s: average latency (%lld us) is outside the thresold (%lld us)", - pp->dev, avglatency, (long long)MAX_AVG_LATENCY); - return DEFAULT_PRIORITY; - } - - /* Min average latency and max average latency are constant, the args base_num - set can change latency_interval value corresponding to avglatency and is not constant. - Warn the user if latency_interval is smaller than (2 * standard_deviation), or equal */ - standard_deviation = calc_standard_deviation(path_latency, index, avglatency); - latency_interval = calc_latency_interval(avglatency, MAX_AVG_LATENCY, MIN_AVG_LATENCY, base_num); - if ((latency_interval!= 0) - && (latency_interval <= (2 * standard_deviation))) - pp_pl_log(3, "%s: latency interval (%lld) according to average latency (%lld us) is smaller than " - "2 * standard deviation (%lld us), or equal, args base_num (%d) needs to be set bigger value", - pp->dev, latency_interval, avglatency, standard_deviation, base_num); - - rc = calcPrio(avglatency, MAX_AVG_LATENCY, MIN_AVG_LATENCY, base_num); - return rc; + int rc, temp; + int index = 0; + int io_num; + int base_num; + long long avglatency; + long long latency_interval; + long long standard_deviation; + long long toldelay = 0; + long long before, after; + struct timespec tv; + + if (pp->fd < 0) + return -1; + + if (get_ionum_and_basenum(args, &io_num, &base_num) == 0) { + pp_pl_log(0, "%s: get path_latency args fail", pp->dev); + return DEFAULT_PRIORITY; + } + + memset(path_latency, 0, sizeof(path_latency)); + + temp = io_num; + while (temp-- > 0) { + (void)clock_gettime(CLOCK_MONOTONIC, &tv); + before = timeval_to_us(&tv); + + if (do_readsector0(pp->fd, timeout) == 2) { + pp_pl_log(0, "%s: path down", pp->dev); + return -1; + } + + (void)clock_gettime(CLOCK_MONOTONIC, &tv); + after = timeval_to_us(&tv); + + path_latency[index] = after - before; + toldelay += path_latency[index++]; + } + + avglatency = toldelay / (long long)io_num; + pp_pl_log(4, "%s: average latency is (%lld us)", pp->dev, avglatency); + + if (avglatency > MAX_AVG_LATENCY) { + pp_pl_log(0, + "%s: average latency (%lld us) is outside the thresold (%lld us)", + pp->dev, avglatency, (long long)MAX_AVG_LATENCY); + return DEFAULT_PRIORITY; + } + + /* + * Min average latency and max average latency are constant, the args + * base_num set can change latency_interval value corresponding to + * avglatency and is not constant. + * Warn the user if latency_interval is smaller than (2 * standard_deviation), + * or equal. + */ + standard_deviation = + calc_standard_deviation(path_latency, index, avglatency); + latency_interval = + calc_latency_interval(avglatency, MAX_AVG_LATENCY, MIN_AVG_LATENCY, + base_num); + if ((latency_interval != 0) + && (latency_interval <= (2 * standard_deviation))) + pp_pl_log(3, + "%s: latency interval (%lld) according to average latency (%lld us) is smaller than " + "2 * standard deviation (%lld us), or equal, args base_num (%d) needs to be set bigger value", + pp->dev, latency_interval, avglatency, + standard_deviation, base_num); + + rc = calcPrio(avglatency, MAX_AVG_LATENCY, MIN_AVG_LATENCY, base_num); + return rc; } -- 2.13.1 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel