CVS commit: xsrc/external/mit/libxshmfence/dist/src
Module Name:xsrc
Committed By: tnn
Date: Sun Feb 23 23:18:01 UTC 2020
Modified Files:
xsrc/external/mit/libxshmfence/dist/src: xshmfence_semaphore.c
xshmfence_semaphore.h
Log Message:
sync from pkgsrc:
> libxshmfence: improve performance of semaphore backend. Bump rev.
>
> It used more locking than necessary. We only need two semaphores.
> One to tell waiters to wake up and one to let the last waiter that
> wakes up notify xshmfence_trigger() it may now return.
To generate a diff of this commit:
cvs rdiff -u -r1.1 -r1.2 \
xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c \
xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c
diff -u xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c:1.1 xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c:1.2
--- xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c:1.1 Sun Aug 14 03:43:37 2016
+++ xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c Sun Feb 23 23:18:01 2020
@@ -33,12 +33,12 @@
#include "xshmfenceint.h"
-static sem_t *mksemtemp(char *, const char *);
+static sem_t *mksemtemp(char *, size_t, const char *);
-#define LOCK() do {} while (sem_wait(f->lock) != 0)
-#define UNLOCK() do { sem_post(f->lock); } while (0)
-#define COND_WAIT() do {} while (sem_wait(f->cond) != 0)
-#define COND_SIGNAL() do { sem_post(f->cond); } while (0)
+#define COND_WAIT_W() do {} while (sem_wait(f->cond_w) != 0)
+#define COND_SIGNAL_W() do { sem_post(f->cond_w); } while (0)
+#define COND_WAIT_T() do {} while (sem_wait(f->cond_t) != 0)
+#define COND_SIGNAL_T() do { sem_post(f->cond_t); } while (0)
/**
* xshmfence_trigger:
@@ -52,30 +52,23 @@ static sem_t *mksemtemp(char *, const ch
int
xshmfence_trigger(struct xshmfence *f) {
int v, waiting;
- LOCK();
v = __sync_bool_compare_and_swap(>triggered, 0, 1);
if (v == 0) {
/* already triggered */
- UNLOCK();
return 0;
}
-
- waiting = __sync_fetch_and_add(>waiting, 0);
- while (waiting > 0) {
- COND_SIGNAL();
- waiting--;
- }
-
- while (__sync_fetch_and_add(>waiting, 0) > 0) {
- /*
- * Busy wait until they all woke up.
- * No new sleepers should arrive since
- * the lock is still held.
- */
- /* yield(); */
+ while ((waiting = __sync_fetch_and_add(>waiting, 0)) > 0) {
+ if (__sync_bool_compare_and_swap(>waiting, waiting, 0)) {
+ __sync_fetch_and_add(>wakeups, waiting);
+ while (waiting--) {
+COND_SIGNAL_W();
+ }
+ COND_WAIT_T();
+ return 0;
+ }
}
- UNLOCK();
+
return 0;
}
@@ -92,24 +85,18 @@ xshmfence_trigger(struct xshmfence *f) {
int
xshmfence_await(struct xshmfence *f) {
- LOCK();
if (__sync_fetch_and_add(>triggered, 0) == 1) {
- UNLOCK();
return 0;
}
do {
__sync_fetch_and_add(>waiting, 1);
- /*
- * These next operations are not atomic.
- * But we busy-wait in xshmfence_trigger, so that's ok.
- */
- UNLOCK();
- COND_WAIT();
- __sync_fetch_and_sub(>waiting, 1);
- LOCK();
+ COND_WAIT_W();
+ } while (__sync_fetch_and_add(>triggered, 0) == 0);
+
+ if (__sync_sub_and_fetch(>wakeups, 1) == 0) {
+ COND_SIGNAL_T();
}
- while (__sync_fetch_and_add(>triggered, 0) == 0);
- UNLOCK();
+
return 0;
}
@@ -121,11 +108,7 @@ xshmfence_await(struct xshmfence *f) {
**/
int
xshmfence_query(struct xshmfence *f) {
- int ret;
- LOCK();
- ret = __sync_fetch_and_add(>triggered, 0);
- UNLOCK();
- return ret;
+ return __sync_fetch_and_add(>triggered, 0);
}
/**
@@ -137,9 +120,7 @@ xshmfence_query(struct xshmfence *f) {
**/
void
xshmfence_reset(struct xshmfence *f) {
- LOCK();
__sync_bool_compare_and_swap(>triggered, 1, 0);
- UNLOCK();
}
/**
@@ -151,27 +132,26 @@ xshmfence_reset(struct xshmfence *f) {
void
xshmfence_init(int fd)
{
- sem_t *lock;
- sem_t *cond;
+ sem_t *cond_w, *cond_t;
struct xshmfence f;
__sync_fetch_and_and(, 0);
__sync_fetch_and_and(, 0);
__sync_fetch_and_and(, 0);
-
- lock = mksemtemp(f.lockname, "/xshmfl-%i");
- if (lock == SEM_FAILED) {
+ __sync_fetch_and_and(, 0);
+
+ cond_w = mksemtemp(f.condname_w, sizeof(f.condname_w), "w");
+ if (cond_w == SEM_FAILED) {
err(EXIT_FAILURE, "xshmfence_init: sem_open");
}
-
- cond = mksemtemp(f.condname, "/xshmfc-%i");
- if (cond == SEM_FAILED) {
+ cond_t = mksemtemp(f.condname_t, sizeof(f.condname_t), "t");
+ if (cond_t == SEM_FAILED) {
err(EXIT_FAILURE, "xshmfence_init: sem_open");
}
-
- sem_close(lock);
- sem_close(cond);
-
+
+ sem_close(cond_w);
+ sem_close(cond_t);
+
pwrite(fd, , sizeof(f), 0);
}
@@ -187,7 +167,7 @@ xshmfence_open_semaphore(struct xshmfenc
/*
* map process local memory to page 2
*/
- if (mmap ((void*)>lock,
+ if (mmap ((void*)>cond_w,
LIBXSHM_PAGESIZE,
PROT_READ|PROT_WRITE,
MAP_FIXED|MAP_ANON,
@@ -195,11 +175,11 @@
CVS commit: xsrc/external/mit/libxshmfence/dist/src
Module Name:xsrc
Committed By: mrg
Date: Sun Aug 14 03:43:37 UTC 2016
Modified Files:
xsrc/external/mit/libxshmfence/dist/src: xshmfence_alloc.c
xshmfenceint.h
Added Files:
xsrc/external/mit/libxshmfence/dist/src: xshmfence_semaphore.c
xshmfence_semaphore.h
Log Message:
port across patches from pkgsrc.
To generate a diff of this commit:
cvs rdiff -u -r1.1.1.1 -r1.2 \
xsrc/external/mit/libxshmfence/dist/src/xshmfence_alloc.c \
xsrc/external/mit/libxshmfence/dist/src/xshmfenceint.h
cvs rdiff -u -r0 -r1.1 \
xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c \
xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: xsrc/external/mit/libxshmfence/dist/src/xshmfence_alloc.c
diff -u xsrc/external/mit/libxshmfence/dist/src/xshmfence_alloc.c:1.1.1.1 xsrc/external/mit/libxshmfence/dist/src/xshmfence_alloc.c:1.2
--- xsrc/external/mit/libxshmfence/dist/src/xshmfence_alloc.c:1.1.1.1 Sat Aug 13 22:04:04 2016
+++ xsrc/external/mit/libxshmfence/dist/src/xshmfence_alloc.c Sun Aug 14 03:43:37 2016
@@ -110,6 +110,9 @@ xshmfence_map_shm(int fd)
close (fd);
return 0;
}
+#ifdef HAVE_SEMAPHORE
+ xshmfence_open_semaphore(addr);
+#endif
return addr;
}
@@ -121,5 +124,8 @@ xshmfence_map_shm(int fd)
void
xshmfence_unmap_shm(struct xshmfence *f)
{
+#ifdef HAVE_SEMAPHORE
+ xshmfence_close_semaphore(f);
+#endif
munmap(f, sizeof (struct xshmfence));
}
Index: xsrc/external/mit/libxshmfence/dist/src/xshmfenceint.h
diff -u xsrc/external/mit/libxshmfence/dist/src/xshmfenceint.h:1.1.1.1 xsrc/external/mit/libxshmfence/dist/src/xshmfenceint.h:1.2
--- xsrc/external/mit/libxshmfence/dist/src/xshmfenceint.h:1.1.1.1 Sat Aug 13 22:04:04 2016
+++ xsrc/external/mit/libxshmfence/dist/src/xshmfenceint.h Sun Aug 14 03:43:37 2016
@@ -32,6 +32,10 @@
#include "xshmfence_futex.h"
#endif
+#if HAVE_SEMAPHORE
+#include "xshmfence_semaphore.h"
+#endif
+
#if HAVE_PTHREAD
#include "xshmfence_pthread.h"
#endif
Added files:
Index: xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c
diff -u /dev/null xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c:1.1
--- /dev/null Sun Aug 14 03:43:37 2016
+++ xsrc/external/mit/libxshmfence/dist/src/xshmfence_semaphore.c Sun Aug 14 03:43:37 2016
@@ -0,0 +1,242 @@
+/*
+ * Copyright © 2015 Tobias Nygren
+ * Copyright © 2013 Keith Packard
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. The copyright holders make no representations
+ * about the suitability of this software for any purpose. It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include
+#include
+#include
+#include
+#include
+
+#include "xshmfenceint.h"
+
+static sem_t *mksemtemp(char *, const char *);
+
+#define LOCK() do {} while (sem_wait(f->lock) != 0)
+#define UNLOCK() do { sem_post(f->lock); } while (0)
+#define COND_WAIT() do {} while (sem_wait(f->cond) != 0)
+#define COND_SIGNAL() do { sem_post(f->cond); } while (0)
+
+/**
+ * xshmfence_trigger:
+ * @f: An X fence
+ *
+ * Set @f to triggered, waking all waiters.
+ *
+ * Return value: 0 on success and -1 on error (in which case, errno
+ * will be set as appropriate).
+ **/
+int
+xshmfence_trigger(struct xshmfence *f) {
+ int v, waiting;
+ LOCK();
+ v = __sync_bool_compare_and_swap(>triggered, 0, 1);
+ if (v == 0) {
+ /* already triggered */
+ UNLOCK();
+ return 0;
+ }
+
+ waiting = __sync_fetch_and_add(>waiting, 0);
+
+ while (waiting > 0) {
+ COND_SIGNAL();
+ waiting--;
+ }
+
+ while (__sync_fetch_and_add(>waiting, 0) > 0) {
+ /*
+ * Busy wait until they all woke up.
+ * No new sleepers should arrive since
+ * the lock is still held.
+ */
+ /* yield(); */
+ }
+ UNLOCK();
+ return 0;
+}
+
+/**
+ * xshmfence_await:
+ * @f: An X fence
+ *
+ * Wait for @f to be triggered. If @f is already triggered, this
+ *
