nuke-redundant-interpreter-locks-experiment

Author: joesuf4

src/modules/perl/modperl_interp.c

@@ -48,7 +48,6 @@ modperl_interp_t *modperl_interp_new(modperl_interp_pool_t *mip,
 
     interp->mip = mip;
     interp->refcnt = 0;
-    MUTEX_INIT(&interp->lock);
 
     if (perl) {
 #ifdef MP_USE_GTOP
@@ -129,7 +128,6 @@ void modperl_interp_destroy(modperl_interp_t *interp)
 
     modperl_xs_dl_handles_close(handles);
 
-    MUTEX_DESTROY(&interp->lock);
     free(interp);
 
 }
@@ -269,22 +267,19 @@ apr_status_t modperl_interp_unselect(void *data)
     modperl_interp_t *interp = (modperl_interp_t *)data;
     modperl_interp_pool_t *mip = interp->mip;
     modperl_tipool_t *tipool = mip->tipool;
-    MUTEX_LOCK(&interp->lock);
     MP_ASSERT(interp && MpInterpIN_USE(interp) && interp->refcnt > 0);
     MP_TRACE_i(MP_FUNC, "unselect(interp=%pp): refcnt=%d",
                interp, interp->refcnt);
 
     if (--interp->refcnt > 0) {
         MP_TRACE_i(MP_FUNC, "interp=0x%lx, refcnt=%d -- interp still in use",
                    (unsigned long)interp, interp->refcnt);
-        MUTEX_UNLOCK(&interp->lock);
         return APR_SUCCESS;
     }
 
     if (!MpInterpIN_USE(interp)){
         MP_TRACE_i(MP_FUNC, "interp=0x%pp, refcnt=%d -- interp already not in use",
                    interp, interp->refcnt);
-        MUTEX_UNLOCK(&interp->lock);
         return APR_SUCCESS;
     }
 
@@ -307,7 +302,7 @@ apr_status_t modperl_interp_unselect(void *data)
         MP_TRACE_i(MP_FUNC, "interp=%pp freed, tipool(size=%ld, in_use=%ld)",
                    interp, tipool->size, tipool->in_use);
     }
-    MUTEX_UNLOCK(&interp->lock);
+
     return APR_SUCCESS;
 }
 
@@ -434,7 +429,7 @@ modperl_interp_t *modperl_interp_select(request_rec *r, conn_rec *c, server_rec
     if (!((r || c) && modperl_threaded_mpm())) {
         interp = scfg->mip->parent;
         MpInterpIN_USE_On(interp);
-        interp->refcnt++;
+        interp->refcnt = 1;
         /* XXX: if no VirtualHosts w/ PerlOptions +Parent we can skip this */
         PERL_SET_CONTEXT(interp->perl);
         /* let the perl interpreter point back to its interp */
@@ -457,14 +452,9 @@ modperl_interp_t *modperl_interp_select(request_rec *r, conn_rec *c, server_rec
     if (c)
         ccfg = modperl_config_con_get(c);
 
-    static perl_mutex lock = PTHREAD_MUTEX_INITIALIZER;
-    MUTEX_LOCK(&lock);
     if (p && (interp = modperl_interp_pool_get(p)) && MpInterpIN_USE(interp)) {
-        MUTEX_LOCK(&interp->lock);
-        MUTEX_UNLOCK(&lock);
         interp->refcnt++;
         interp->num_requests++;
-        MUTEX_UNLOCK(&interp->lock);
         MP_TRACE_i(MP_FUNC,
                    "found interp 0x%lx (perl=0x%pp) in r->pool config, refcnt=%d",
                    (unsigned long)interp, interp->perl, interp->refcnt);
@@ -475,7 +465,6 @@ modperl_interp_t *modperl_interp_select(request_rec *r, conn_rec *c, server_rec
     MP_TRACE_i(MP_FUNC,
                "fetching interp for %s:%d", s->server_hostname, s->port);
     interp = modperl_interp_get(s);
-    MUTEX_LOCK(&interp->lock);
     MP_TRACE_i(MP_FUNC, "  --> got %pp (perl=%pp)", interp, interp->perl);
     ++interp->num_requests; /* should only get here once per request */
     interp->refcnt = 1;
@@ -512,8 +501,6 @@ modperl_interp_t *modperl_interp_select(request_rec *r, conn_rec *c, server_rec
         */
         interp->refcnt++, set_interp(p), interp->pool = p;
 
-    MUTEX_UNLOCK(&interp->lock);
-    MUTEX_UNLOCK(&lock);
     return interp;
 }
 

src/modules/perl/modperl_types.h

@@ -67,7 +67,6 @@ struct modperl_interp_t {
 #ifdef MP_TRACE
     unsigned long tid;
 #endif
-    perl_mutex lock;
 };
 
 typedef struct {