performance improvements

1 files changed, 83 insertions, 14 deletions

diff --git a/lib/fuse_mt.c b/lib/fuse_mt.c
index 19cc33c..6120554 100644
--- a/lib/fuse_mt.c
+++ b/lib/fuse_mt.c
@@ -13,23 +13,64 @@
 #include <string.h>
 #include <pthread.h>
 #include <signal.h>
+#include <errno.h>
+#include <sys/time.h>
 
-struct fuse_thr_data {
+#define FUSE_WORKER_IDLE 10
+
+static pthread_mutex_t fuse_mt_lock = PTHREAD_MUTEX_INITIALIZER;
+
+
+struct fuse_worker {
+    struct fuse_worker *next;
+    struct fuse_worker *prev;
     struct fuse *f;
     void *data;
     fuse_processor_t proc;
     struct fuse_cmd *cmd;
+    int avail;
+    pthread_cond_t start;
 };
 
 static void *do_work(void *data)
 {
-    struct fuse_thr_data *d = (struct fuse_thr_data *) data;
-    d->proc(d->f, d->cmd, d->data);
-    free(d);
+    struct fuse_worker *w = (struct fuse_worker *) data;
+    int ret;
+    
+    do {
+        struct timeval now;
+        struct timespec timeout;
+
+        w->proc(w->f, w->cmd, w->data);
+
+        pthread_mutex_lock(&fuse_mt_lock);
+        w->avail = 1;
+        w->cmd = NULL;
+        gettimeofday(&now, NULL);
+        timeout.tv_sec = now.tv_sec + FUSE_WORKER_IDLE;
+        timeout.tv_nsec = now.tv_usec * 1000;
+
+        ret = 0;
+        while(w->cmd == NULL && ret != ETIMEDOUT)
+            ret = pthread_cond_timedwait(&w->start, &fuse_mt_lock, &timeout);
+
+        if(ret == ETIMEDOUT) {
+            struct fuse_worker *next = w->next;
+            struct fuse_worker *prev = w->prev;
+            prev->next = next;
+            next->prev = prev;
+            pthread_cond_destroy(&w->start);
+            free(w);
+        }
+        w->avail = 0;
+        pthread_mutex_unlock(&fuse_mt_lock);
+
+    } while(ret != ETIMEDOUT);
+
     return NULL;
 }
 
-static void start_thread(struct fuse_thr_data *d)
+static void start_thread(struct fuse_worker *w)
 {
     pthread_t thrid;
     sigset_t oldset;
@@ -39,7 +80,7 @@ static void start_thread(struct fuse_thr_data *d)
     /* Disallow signal reception in worker threads */
     sigfillset(&newset);
     pthread_sigmask(SIG_SETMASK, &newset, &oldset);
-    res = pthread_create(&thrid, NULL, do_work, d);
+    res = pthread_create(&thrid, NULL, do_work, w);
     pthread_sigmask(SIG_SETMASK, &oldset, NULL);
     if(res != 0) {
         fprintf(stderr, "Error creating thread: %s\n", strerror(res));
@@ -50,19 +91,47 @@ static void start_thread(struct fuse_thr_data *d)
 
 void __fuse_loop_mt(struct fuse *f, fuse_processor_t proc, void *data)
 {
+    struct fuse_worker *head;
+
+    head = malloc(sizeof(struct fuse_worker));
+    head->next = head;
+    head->prev = head;
+
     while(1) {
-        struct fuse_thr_data *d;
+        struct fuse_worker *w;
         struct fuse_cmd *cmd = __fuse_read_cmd(f);
         if(cmd == NULL)
             exit(1);
 
-        d = malloc(sizeof(struct fuse_thr_data));
-        d->proc = proc;
-        d->f = f;
-        d->cmd = cmd;
-        d->data = data;
-        
-        start_thread(d);
+        pthread_mutex_lock(&fuse_mt_lock);
+        for(w = head->next; w != head; w = w->next) 
+            if(w->avail)
+                break;
+
+        if(w != head) {
+            pthread_cond_signal(&w->start);
+            w->cmd = cmd;
+            w = NULL;
+        }
+        else {
+            struct fuse_worker *prev = head->prev;
+            struct fuse_worker *next = head;
+            w = malloc(sizeof(struct fuse_worker));
+            w->prev = prev;
+            w->next = next;
+            next->prev = w;
+            prev->next = w;
+            w->f = f;
+            w->data = data;
+            w->proc = proc;
+            w->cmd = cmd;
+            w->avail = 0;
+            pthread_cond_init(&w->start, NULL);
+        }
+        pthread_mutex_unlock(&fuse_mt_lock);
+
+        if(w != NULL)
+            start_thread(w);
     }
 }