The following changes since commit d1ab783430f5a832e973ed9a293da146c04c6702:
iowatcher: link with -lrt (2016-08-23 08:45:45 -0600)
are available in the git repository at:
git://git.kernel.dk/blktrace.git master
for you to fetch changes up to 8772bc4fb049bdd879de5952d6f291a34112fae0:
blktrace: Create empty output files for non-existent cpus (2017-01-26 10:06:05 -0700)
----------------------------------------------------------------
Jan Kara (3):
blktrace: Add support for sparse CPU numbers
blktrace: Reorganize creation of output file name
blktrace: Create empty output files for non-existent cpus
blktrace.c | 191 ++++++++++++++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 156 insertions(+), 35 deletions(-)
---
Diff of recent changes:
diff --git a/blktrace.c b/blktrace.c
index b445524..e8f2f87 100644
--- a/blktrace.c
+++ b/blktrace.c
@@ -274,7 +274,9 @@ static char blktrace_version[] = "2.0.0";
int data_is_native = -1;
static int ndevs;
+static int max_cpus;
static int ncpus;
+static cpu_set_t *online_cpus;
static int pagesize;
static int act_mask = ~0U;
static int kill_running_trace;
@@ -623,8 +625,9 @@ static int lock_on_cpu(int cpu)
{
cpu_set_t * cpu_mask;
size_t size;
- cpu_mask = CPU_ALLOC(ncpus);
- size = CPU_ALLOC_SIZE(ncpus);
+
+ cpu_mask = CPU_ALLOC(max_cpus);
+ size = CPU_ALLOC_SIZE(max_cpus);
CPU_ZERO_S(size, cpu_mask);
CPU_SET_S(cpu, size, cpu_mask);
@@ -882,7 +885,7 @@ static int net_send_header(int fd, int cpu, char *buts_name, int len)
strncpy(hdr.buts_name, buts_name, sizeof(hdr.buts_name));
hdr.buts_name[sizeof(hdr.buts_name) - 1] = '\0';
hdr.cpu = cpu;
- hdr.max_cpus = ncpus;
+ hdr.max_cpus = max_cpus;
hdr.len = len;
hdr.cl_id = getpid();
hdr.buf_size = buf_size;
@@ -1026,9 +1029,12 @@ static int net_setup_client(void)
static int open_client_connections(void)
{
int cpu;
+ size_t alloc_size = CPU_ALLOC_SIZE(max_cpus);
cl_fds = calloc(ncpus, sizeof(*cl_fds));
- for (cpu = 0; cpu < ncpus; cpu++) {
+ for (cpu = 0; cpu < max_cpus; cpu++) {
+ if (!CPU_ISSET_S(cpu, alloc_size, online_cpus))
+ continue;
cl_fds[cpu] = net_setup_client();
if (cl_fds[cpu] < 0)
goto err;
@@ -1046,8 +1052,11 @@ static void close_client_connections(void)
{
if (cl_fds) {
int cpu, *fdp;
+ size_t alloc_size = CPU_ALLOC_SIZE(max_cpus);
- for (cpu = 0, fdp = cl_fds; cpu < ncpus; cpu++, fdp++) {
+ for (cpu = 0, fdp = cl_fds; cpu < max_cpus; cpu++, fdp++) {
+ if (!CPU_ISSET_S(cpu, alloc_size, online_cpus))
+ continue;
if (*fdp >= 0) {
net_send_drops(*fdp);
net_close_connection(fdp);
@@ -1071,7 +1080,7 @@ static void setup_buts(void)
buts.act_mask = act_mask;
if (ioctl(dpp->fd, BLKTRACESETUP, &buts) >= 0) {
- dpp->ncpus = ncpus;
+ dpp->ncpus = max_cpus;
dpp->buts_name = strdup(buts.name);
if (dpp->stats)
free(dpp->stats);
@@ -1155,7 +1164,7 @@ static void free_tracer_heads(struct devpath *dpp)
int cpu;
struct tracer_devpath_head *hd;
- for (cpu = 0, hd = dpp->heads; cpu < ncpus; cpu++, hd++) {
+ for (cpu = 0, hd = dpp->heads; cpu < max_cpus; cpu++, hd++) {
if (hd->prev)
free(hd->prev);
@@ -1177,8 +1186,8 @@ static int setup_tracer_devpaths(void)
struct tracer_devpath_head *hd;
struct devpath *dpp = list_entry(p, struct devpath, head);
- dpp->heads = calloc(ncpus, sizeof(struct tracer_devpath_head));
- for (cpu = 0, hd = dpp->heads; cpu < ncpus; cpu++, hd++) {
+ dpp->heads = calloc(max_cpus, sizeof(struct tracer_devpath_head));
+ for (cpu = 0, hd = dpp->heads; cpu < max_cpus; cpu++, hd++) {
INIT_LIST_HEAD(&hd->head);
pthread_mutex_init(&hd->mutex, NULL);
hd->prev = NULL;
@@ -1426,7 +1435,7 @@ static void __process_trace_bufs(void)
struct devpath *dpp = list_entry(p, struct devpath, head);
struct tracer_devpath_head *hd = dpp->heads;
- for (cpu = 0; cpu < ncpus; cpu++, hd++) {
+ for (cpu = 0; cpu < max_cpus; cpu++, hd++) {
pthread_mutex_lock(&hd->mutex);
if (list_empty(&hd->head)) {
pthread_mutex_unlock(&hd->mutex);
@@ -1493,30 +1502,25 @@ static inline int net_sendfile_data(struct tracer *tp, struct io_info *iop)
return net_sendfile(iop);
}
-static int fill_ofname(struct io_info *iop, int cpu)
+static int fill_ofname(char *dst, int dstlen, char *subdir, char *buts_name,
+ int cpu)
{
int len;
struct stat sb;
- char *dst = iop->ofn;
if (output_dir)
- len = snprintf(iop->ofn, sizeof(iop->ofn), "%s/", output_dir);
+ len = snprintf(dst, dstlen, "%s/", output_dir);
else
- len = snprintf(iop->ofn, sizeof(iop->ofn), "./");
+ len = snprintf(dst, dstlen, "./");
- if (net_mode == Net_server) {
- struct cl_conn *nc = iop->nc;
-
- len += sprintf(dst + len, "%s-", nc->ch->hostname);
- len += strftime(dst + len, 64, "%F-%T/",
- gmtime(&iop->dpp->cl_connect_time));
- }
+ if (subdir)
+ len += snprintf(dst + len, dstlen - len, "%s", subdir);
- if (stat(iop->ofn, &sb) < 0) {
+ if (stat(dst, &sb) < 0) {
if (errno != ENOENT) {
fprintf(stderr,
"Destination dir %s stat failed: %d/%s\n",
- iop->ofn, errno, strerror(errno));
+ dst, errno, strerror(errno));
return 1;
}
/*
@@ -1524,20 +1528,20 @@ static int fill_ofname(struct io_info *iop, int cpu)
* trying to create the directory at once. It's harmless
* to let them try, so just detect the problem and move on.
*/
- if (mkdir(iop->ofn, 0755) < 0 && errno != EEXIST) {
+ if (mkdir(dst, 0755) < 0 && errno != EEXIST) {
fprintf(stderr,
"Destination dir %s can't be made: %d/%s\n",
- iop->ofn, errno, strerror(errno));
+ dst, errno, strerror(errno));
return 1;
}
}
if (output_name)
- snprintf(iop->ofn + len, sizeof(iop->ofn), "%s.blktrace.%d",
+ snprintf(dst + len, dstlen - len, "%s.blktrace.%d",
output_name, cpu);
else
- snprintf(iop->ofn + len, sizeof(iop->ofn), "%s.blktrace.%d",
- iop->dpp->buts_name, cpu);
+ snprintf(dst + len, dstlen - len, "%s.blktrace.%d",
+ buts_name, cpu);
return 0;
}
@@ -1558,8 +1562,23 @@ static int set_vbuf(struct io_info *iop, int mode, size_t size)
static int iop_open(struct io_info *iop, int cpu)
{
+ char hostdir[MAXPATHLEN + 64];
+
iop->ofd = -1;
- if (fill_ofname(iop, cpu))
+ if (net_mode == Net_server) {
+ struct cl_conn *nc = iop->nc;
+ int len;
+
+ len = snprintf(hostdir, sizeof(hostdir), "%s-",
+ nc->ch->hostname);
+ len += strftime(hostdir + len, sizeof(hostdir) - len, "%F-%T/",
+ gmtime(&iop->dpp->cl_connect_time));
+ } else {
+ hostdir[0] = 0;
+ }
+
+ if (fill_ofname(iop->ofn, sizeof(iop->ofn), hostdir,
+ iop->dpp->buts_name, cpu))
return 1;
iop->ofp = my_fopen(iop->ofn, "w+");
@@ -1874,16 +1893,49 @@ static int start_tracer(int cpu)
return 0;
}
+static int create_output_files(int cpu)
+{
+ char fname[MAXPATHLEN + 64];
+ struct list_head *p;
+ FILE *f;
+
+ __list_for_each(p, &devpaths) {
+ struct devpath *dpp = list_entry(p, struct devpath, head);
+
+ if (fill_ofname(fname, sizeof(fname), NULL, dpp->buts_name,
+ cpu))
+ return 1;
+ f = my_fopen(fname, "w+");
+ if (!f)
+ return 1;
+ fclose(f);
+ }
+ return 0;
+}
+
static void start_tracers(void)
{
- int cpu;
+ int cpu, started = 0;
struct list_head *p;
+ size_t alloc_size = CPU_ALLOC_SIZE(max_cpus);
- for (cpu = 0; cpu < ncpus; cpu++)
+ for (cpu = 0; cpu < max_cpus; cpu++) {
+ if (!CPU_ISSET_S(cpu, alloc_size, online_cpus)) {
+ /*
+ * Create fake empty output files so that other tools
+ * like blkparse don't have to bother with sparse CPU
+ * number space.
+ */
+ if (create_output_files(cpu))
+ break;
+ continue;
+ }
if (start_tracer(cpu))
break;
+ started++;
+ }
- wait_tracers_ready(cpu);
+ wait_tracers_ready(started);
__list_for_each(p, &tracers) {
struct tracer *tp = list_entry(p, struct tracer, head);
@@ -2657,15 +2709,83 @@ static int run_tracers(void)
return 0;
}
+static cpu_set_t *get_online_cpus(void)
+{
+ FILE *cpus;
+ cpu_set_t *set;
+ size_t alloc_size;
+ int cpuid, prevcpuid = -1;
+ char nextch;
+ int n, ncpu, curcpu = 0;
+ int *cpu_nums;
+
+ ncpu = sysconf(_SC_NPROCESSORS_CONF);
+ if (ncpu < 0)
+ return NULL;
+
+ cpu_nums = malloc(sizeof(int)*ncpu);
+ if (!cpu_nums) {
+ errno = ENOMEM;
+ return NULL;
+ }
+
+ /*
+ * There is no way to easily get maximum CPU number. So we have to
+ * parse the file first to find it out and then create appropriate
+ * cpuset
+ */
+ cpus = my_fopen("/sys/devices/system/cpu/online", "r");
+ for (;;) {
+ n = fscanf(cpus, "%d%c", &cpuid, &nextch);
+ if (n <= 0)
+ break;
+ if (n == 2 && nextch == '-') {
+ prevcpuid = cpuid;
+ continue;
+ }
+ if (prevcpuid == -1)
+ prevcpuid = cpuid;
+ while (prevcpuid <= cpuid) {
+ /* More CPUs listed than configured? */
+ if (curcpu >= ncpu) {
+ errno = EINVAL;
+ return NULL;
+ }
+ cpu_nums[curcpu++] = prevcpuid++;
+ }
+ prevcpuid = -1;
+ }
+ fclose(cpus);
+
+ ncpu = curcpu;
+ max_cpus = cpu_nums[ncpu - 1] + 1;
+
+ /* Now that we have maximum cpu number, create a cpuset */
+ set = CPU_ALLOC(max_cpus);
+ if (!set) {
+ errno = ENOMEM;
+ return NULL;
+ }
+ alloc_size = CPU_ALLOC_SIZE(max_cpus);
+ CPU_ZERO_S(alloc_size, set);
+
+ for (curcpu = 0; curcpu < ncpu; curcpu++)
+ CPU_SET_S(cpu_nums[curcpu], alloc_size, set);
+
+ free(cpu_nums);
+
+ return set;
+}
+
int main(int argc, char *argv[])
{
int ret = 0;
setlocale(LC_NUMERIC, "en_US");
pagesize = getpagesize();
- ncpus = sysconf(_SC_NPROCESSORS_ONLN);
- if (ncpus < 0) {
- fprintf(stderr, "sysconf(_SC_NPROCESSORS_ONLN) failed %d/%s\n",
+ online_cpus = get_online_cpus();
+ if (!online_cpus) {
+ fprintf(stderr, "cannot get online cpus %d/%s\n",
errno, strerror(errno));
ret = 1;
goto out;
@@ -2674,6 +2794,7 @@ int main(int argc, char *argv[])
goto out;
}
+ ncpus = CPU_COUNT_S(CPU_ALLOC_SIZE(max_cpus), online_cpus);
if (ndevs > 1 && output_name && strcmp(output_name, "-") != 0) {
fprintf(stderr, "-o not supported with multiple devices\n");
ret = 1;
--
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