Dynamically allocate bootchart logs

Instead of storing bootchart sample data in arrays, this patch moves
storage to linked lists so that there is no more limit on samples.

This patch also fixes parsing of /proc/<pid>/smaps in kernels > 3.7.

1 files changed, 34 insertions, 14 deletions

diff --git a/src/bootchart/bootchart.c b/src/bootchart/bootchart.c
index b73319123f..8be5a27afa 100644
--- a/src/bootchart/bootchart.c
+++ b/src/bootchart/bootchart.c
@@ -59,14 +59,11 @@
 #include "store.h"
 #include "svg.h"
 #include "bootchart.h"
+#include "list.h"
 
 double graph_start;
 double log_start;
-double sampletime[MAXSAMPLES];
 struct ps_struct *ps_first;
-struct block_stat_struct blockstat[MAXSAMPLES];
-int entropy_avail[MAXSAMPLES];
-struct cpu_stat_struct cpustat[MAXCPUS];
 int pscount;
 int cpus;
 double interval;
@@ -87,6 +84,8 @@ int arg_samples_len = 500; /* we record len+1 (1 start sample) */
 double arg_hz = 25.0;   /* 20 seconds log time */
 double arg_scale_x = 100.0; /* 100px = 1sec */
 double arg_scale_y = 20.0;  /* 16px = 1 process bar */
+static struct list_sample_data *sampledata;
+struct list_sample_data *head;
 
 char arg_init_path[PATH_MAX] = "/sbin/init";
 char arg_output_path[PATH_MAX] = "/run/log";
@@ -227,11 +226,6 @@ static int parse_args(int argc, char *argv[]) {
                 }
         }
 
-        if (arg_samples_len > MAXSAMPLES) {
-                fprintf(stderr, "Error: samples exceeds maximum\n");
-                return -EINVAL;
-        }
-
         if (arg_hz <= 0.0) {
                 fprintf(stderr, "Error: Frequency needs to be > 0\n");
                 return -EINVAL;
@@ -338,6 +332,8 @@ int main(int argc, char *argv[]) {
 
         log_uptime();
 
+        LIST_HEAD_INIT(struct list_sample_data, head);
+
         /* main program loop */
         for (samples = 0; !exiting && samples < arg_samples_len; samples++) {
                 int res;
@@ -348,7 +344,14 @@ int main(int argc, char *argv[]) {
                 double elapsed;
                 double timeleft;
 
-                sampletime[samples] = gettime_ns();
+                sampledata = new0(struct list_sample_data, 1);
+                if (sampledata == NULL) {
+                        log_error("Failed to allocate memory for a node: %m");
+                        return -1;
+                }
+
+                sampledata->sampletime = gettime_ns();
+                sampledata->counter = samples;
 
                 if (!of && (access(arg_output_path, R_OK|W_OK|X_OK) == 0)) {
                         t = time(NULL);
@@ -369,11 +372,11 @@ int main(int argc, char *argv[]) {
                 if (graph_start <= 0.0)
                         log_uptime();
                 else
-                        log_sample(samples);
+                        log_sample(samples, &sampledata);
 
                 sample_stop = gettime_ns();
 
-                elapsed = (sample_stop - sampletime[samples]) * 1000000000.0;
+                elapsed = (sample_stop - sampledata->sampletime) * 1000000000.0;
                 timeleft = interval - elapsed;
 
                 newint_s = (time_t)(timeleft / 1000000000.0);
@@ -403,6 +406,7 @@ int main(int argc, char *argv[]) {
                         /* calculate how many samples we lost and scrap them */
                         arg_samples_len -= (int)(newint_ns / interval);
                 }
+                LIST_PREPEND(struct list_sample_data, link, head, sampledata);
         }
 
         /* do some cleanup, close fd's */
@@ -443,16 +447,32 @@ int main(int argc, char *argv[]) {
                 close(sysfd);
 
         /* nitpic cleanups */
-        ps = ps_first;
+        ps = ps_first->next_ps;
         while (ps->next_ps) {
-                struct ps_struct *old = ps;
+                struct ps_struct *old;
+
+                old = ps;
+                old->sample = ps->first;
                 ps = ps->next_ps;
+                while (old->sample->next) {
+                        struct ps_sched_struct *oldsample = old->sample;
+
+                        old->sample = old->sample->next;
+                        free(oldsample);
+                }
                 free(old->sample);
                 free(old);
         }
         free(ps->sample);
         free(ps);
 
+        sampledata = head;
+        while (sampledata->link_prev) {
+                struct list_sample_data *old_sampledata = sampledata;
+                sampledata = sampledata->link_prev;
+                free(old_sampledata);
+        }
+        free(sampledata);
         /* don't complain when overrun once, happens most commonly on 1st sample */
         if (overrun > 1)
                 fprintf(stderr, "systemd-boochart: Warning: sample time overrun %i times\n", overrun);