Hi, Please find attached a patch that removes the hardcoded number of threads and allows setting the number of worker threads from the commandline using the new arguments -t/--threads . The default value for number of threads, if -t/--threads are not specified, is 4, to match the behaviour of tgtd before this patch. Attached both as text and in gzip format in case gmail mangles the patch. regards ronnie sahlberg
From 4261a4704556029c7e1c134d29244e9a139b0bc1 Mon Sep 17 00:00:00 2001
From: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx>
Date: Mon, 21 Sep 2009 11:52:55 +1000
Subject: [PATCH] Add an argument --threads/-t to allow setting the number of threads at runtime.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx>
---
usr/bs.c | 24 ++++++++++++++----------
usr/bs_mmap.c | 2 +-
usr/bs_rdwr.c | 2 +-
usr/bs_thread.h | 4 ++--
usr/tgtd.c | 11 ++++++++++-
usr/tgtd.h | 1 +
6 files changed, 29 insertions(+), 15 deletions(-)
diff --git a/usr/bs.c b/usr/bs.c
index d0fcce4..2b070c0 100644
--- a/usr/bs.c
+++ b/usr/bs.c
@@ -276,6 +276,14 @@ int bs_thread_open(struct bs_thread_info *info, request_func_t *rfn,
pthread_mutex_init(&info->pending_lock, NULL);
pthread_mutex_init(&info->startup_lock, NULL);
+ info->num_worker_threads = nr_threads;
+ info->worker_threads = malloc(sizeof(pthread_t *) * nr_threads);
+ if (info->worker_threads == NULL) {
+ eprintf("failed to allocate array for %d threads\n",
+ nr_threads);
+ goto destroy_cond_mutex;
+ }
+
ret = pipe(info->command_fd);
if (ret) {
eprintf("failed to create command pipe, %m\n");
@@ -303,14 +311,10 @@ int bs_thread_open(struct bs_thread_info *info, request_func_t *rfn,
goto event_del;
}
- if (nr_threads > ARRAY_SIZE(info->worker_thread)) {
- eprintf("too many threads %d\n", nr_threads);
- nr_threads = ARRAY_SIZE(info->worker_thread);
- }
-
+ dprintf("starting %d threads\n", nr_threads);
pthread_mutex_lock(&info->startup_lock);
for (i = 0; i < nr_threads; i++) {
- ret = pthread_create(&info->worker_thread[i], NULL,
+ ret = pthread_create(&info->worker_threads[i], NULL,
bs_thread_worker_fn, info);
if (ret) {
@@ -339,7 +343,7 @@ destroy_threads:
pthread_mutex_unlock(&info->startup_lock);
for (; i > 0; i--) {
- pthread_join(info->worker_thread[i - 1], NULL);
+ pthread_join(info->worker_threads[i - 1], NULL);
eprintf("stopped the worker thread %d\n", i - 1);
}
event_del:
@@ -372,9 +376,9 @@ void bs_thread_close(struct bs_thread_info *info)
info->stop = 1;
pthread_cond_broadcast(&info->pending_cond);
- for (i = 0; info->worker_thread[i] &&
- i < ARRAY_SIZE(info->worker_thread); i++)
- pthread_join(info->worker_thread[i], NULL);
+ for (i = 0; info->worker_threads[i] &&
+ i < info->num_worker_threads; i++)
+ pthread_join(info->worker_threads[i], NULL);
pthread_cond_destroy(&info->finished_cond);
pthread_cond_destroy(&info->pending_cond);
diff --git a/usr/bs_mmap.c b/usr/bs_mmap.c
index b62c8e6..46c0981 100644
--- a/usr/bs_mmap.c
+++ b/usr/bs_mmap.c
@@ -93,7 +93,7 @@ static void bs_mmap_close(struct scsi_lu *lu)
static int bs_mmap_init(struct scsi_lu *lu)
{
struct bs_thread_info *info = BS_THREAD_I(lu);
- return bs_thread_open(info, bs_mmap_request, NR_WORKER_THREADS);
+ return bs_thread_open(info, bs_mmap_request, num_worker_threads);
}
static void bs_mmap_exit(struct scsi_lu *lu)
diff --git a/usr/bs_rdwr.c b/usr/bs_rdwr.c
index 6068479..4dfc617 100644
--- a/usr/bs_rdwr.c
+++ b/usr/bs_rdwr.c
@@ -146,7 +146,7 @@ static int bs_rdwr_init(struct scsi_lu *lu)
{
struct bs_thread_info *info = BS_THREAD_I(lu);
- return bs_thread_open(info, bs_rdwr_request, NR_WORKER_THREADS);
+ return bs_thread_open(info, bs_rdwr_request, num_worker_threads);
}
static void bs_rdwr_exit(struct scsi_lu *lu)
diff --git a/usr/bs_thread.h b/usr/bs_thread.h
index 9dfbbd5..0509059 100644
--- a/usr/bs_thread.h
+++ b/usr/bs_thread.h
@@ -1,10 +1,10 @@
-#define NR_WORKER_THREADS 4
typedef void (request_func_t) (struct scsi_cmd *);
struct bs_thread_info {
pthread_t ack_thread;
- pthread_t worker_thread[NR_WORKER_THREADS];
+ int num_worker_threads;
+ pthread_t *worker_threads;
/* protected by pipe */
struct list_head ack_list;
diff --git a/usr/tgtd.c b/usr/tgtd.c
index b07a445..fe5ae2b 100644
--- a/usr/tgtd.c
+++ b/usr/tgtd.c
@@ -42,6 +42,7 @@
unsigned long pagesize, pageshift, pagemask;
int system_active = 1;
+int num_worker_threads;
static int ep_fd;
static char program_name[] = "tgtd";
static LIST_HEAD(tgt_events_list);
@@ -50,12 +51,13 @@ static LIST_HEAD(tgt_sched_events_list);
static struct option const long_options[] =
{
{"foreground", no_argument, 0, 'f'},
+ {"threads", required_argument, 0, 't'},
{"debug", required_argument, 0, 'd'},
{"help", no_argument, 0, 'h'},
{0, 0, 0, 0},
};
-static char *short_options = "fd:h";
+static char *short_options = "fd:ht:";
static void usage(int status)
{
@@ -66,6 +68,7 @@ static void usage(int status)
printf("\
Target framework daemon, version %s\n\
-f, --foreground make the program run in the foreground\n\
+ -t, --threads num number of pthreads to use\n\
-d, --debug debuglevel print debugging information\n\
-h, --help display this help and exit\n\
", TGT_VERSION);
@@ -334,6 +337,9 @@ int main(int argc, char **argv)
case 'f':
is_daemon = 0;
break;
+ case 't':
+ num_worker_threads = atoi(optarg);
+ break;
case 'd':
is_debug = atoi(optarg);
break;
@@ -349,6 +355,9 @@ int main(int argc, char **argv)
}
}
+ if (num_worker_threads == 0)
+ num_worker_threads = 4;
+
err = log_init(program_name, LOG_SPACE_SIZE, is_daemon, is_debug);
if (err)
exit(1);
diff --git a/usr/tgtd.h b/usr/tgtd.h
index 303627e..fe8e4bb 100644
--- a/usr/tgtd.h
+++ b/usr/tgtd.h
@@ -185,6 +185,7 @@ static inline int kreq_init(void) \
#endif
extern int system_active;
+extern int num_worker_threads;
extern int kspace_send_tsk_mgmt_res(struct mgmt_req *mreq);
extern int kspace_send_cmd_res(uint64_t nid, int result, struct scsi_cmd *);
--
1.5.6
Attachment:
0001-Add-an-argument-threads-t-to-allow-setting-the-nu.patch.gz
Description: GNU Zip compressed data
