[CRIU] [PATCH v2 5/6] log_dirty: add log_dirty_total - get total amount of dirty memory pages

[Pavel Tikhomirov]

iterate through all processes in dump tree and update total_pages,
and total_dirty_pages counters, write summs for all tree to image
do not continuously iterate, add sleep to increase iteration
time by say 1.5 every step

v2: merge sleep_us to these patch to fix compilation warn that
function is unused

Signed-off-by: Pavel Tikhomirov <ptikhomirov at virtuozzo.com>
---
 criu/dirty-logger.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 120 insertions(+)

diff --git a/criu/dirty-logger.c b/criu/dirty-logger.c
index 745c289..811be23 100644
--- a/criu/dirty-logger.c
+++ b/criu/dirty-logger.c
@@ -1,18 +1,94 @@
 #include <pthread.h>
+#include <sys/time.h>
 
 #include "imgset.h"
+#include "pstree.h"
+#include "protobuf.h"
+
+#include "images/stats.pb-c.h"
+
+#define NSEC_PER_USEC	1000L
+#define USEC_PER_SEC	1000000L
+
+static int sleep_us(long us) {
+	struct timespec ts, rts;
+	ts.tv_sec = us / USEC_PER_SEC;
+	ts.tv_nsec = NSEC_PER_USEC * (us % USEC_PER_SEC);
+	while (nanosleep(&ts, &rts)) {
+		if (errno != EINTR)
+			return -1;
+		ts = rts;
+	}
+
+	return 0;
+}
 
 void img_cleanup(void *arg)
 {
        close_image((struct cr_img *)arg);
 }
 
+static int pid_log_dirty_total(pid_t pid, long *total_pages, long *total_dirty_pages)
+{
+	return 0;
+}
+
+static int log_dirty_total(struct cr_img *img, struct timeval *start)
+{
+	struct pstree_item *item;
+	long total_pages = 0;
+	long total_dirty_pages = 0;
+	struct timeval tv;
+	int ret;
+	DirtyLogEntry dle = DIRTY_LOG_ENTRY__INIT;
+
+	/*
+	 * Calculate dirty pages total cout across the tree
+	 */
+	for_each_pstree_item(item) {
+		if (pid_log_dirty_total(item->pid.real, &total_pages, &total_dirty_pages))
+			return -1;
+	}
+
+	ret = gettimeofday(&tv, NULL);
+	if (ret == -1) {
+		pr_perror("Failed gettimeofday");
+		return -1;
+	}
+	timediff(start, &tv);
+
+	dle.sec = tv.tv_sec;
+	dle.usec = tv.tv_usec;
+	dle.total_pages = total_pages;
+	dle.total_dirty_pages = total_dirty_pages;
+
+	ret = pb_write_one(img, &dle, PB_DIRTY_LOG);
+	if (ret == -1) {
+		pr_perror("Failed pb_write_one");
+		return -1;
+	}
+
+	return 0;
+}
+
 #define CR_DIRTY_LOG "dirty-log.img"
 
+#define INC_ITER_TIME 1.5
+
 void *dirty_logger_pthread(void *arg)
 {
 	int *pret = (int *)arg;
 	struct cr_img *img;
+	long double next_iter_time = 0;
+	struct timeval start;
+	int ret;
+
+	ret = gettimeofday(&start, NULL);
+	if (ret == -1) {
+		pr_perror("Failed gettimeofday");
+		*pret = -1;
+		pthread_exit(NULL);
+	}
 
 	img = open_image_at(AT_FDCWD, CR_FD_DIRTY_LOG, O_DUMP);
 	if (!img) {
@@ -21,6 +97,50 @@ void *dirty_logger_pthread(void *arg)
 	}
 	pthread_cleanup_push(img_cleanup, (void *)img);
 
+	while(1) {
+		struct timeval iter_start, iter_end;
+		long sleep_time;
+
+		ret = gettimeofday(&iter_start, NULL);
+		if (ret == -1) {
+			pr_perror("Failed gettimeofday");
+			*pret = -1;
+			pthread_exit(NULL);
+		}
+
+		ret = log_dirty_total(img, &start);
+		if (ret == -1) {
+			*pret = -1;
+			pthread_exit(NULL);
+		}
+
+		ret = gettimeofday(&iter_end, NULL);
+		if (ret == -1) {
+			pr_perror("Failed gettimeofday");
+			*pret = -1;
+			pthread_exit(NULL);
+		}
+
+		timediff(&iter_start, &iter_end);
+
+		if (!next_iter_time)
+			next_iter_time = iter_end.tv_sec * USEC_PER_SEC
+				+ iter_end.tv_usec;
+
+		sleep_time = next_iter_time - (iter_end.tv_sec * USEC_PER_SEC
+				+ iter_end.tv_usec);
+		if (sleep_time <= 0)
+			continue;
+
+		ret = sleep_us((long)sleep_time);
+		if (ret == -1) {
+			pr_perror("Failed sleep_us");
+			*pret = -1;
+			pthread_exit(NULL);
+		}
+		next_iter_time *= INC_ITER_TIME;
+	}
+
 	*pret = 0;
 	pthread_cleanup_pop(1);
 	pthread_exit(NULL);
-- 
2.5.5