diff mbox series

[v2,6/9] util: Share qemu_try_memalign() implementation between POSIX and Windows

Message ID 20220304112126.2261039-7-peter.maydell@linaro.org
State Superseded
Headers show
Series Cleanup of qemu_oom_check() and qemu_memalign() | expand

Commit Message

Peter Maydell March 4, 2022, 11:21 a.m. UTC 
The qemu_try_memalign() functions for POSIX and Windows used to be
significantly different, but these days they are identical except for
the actual allocation function called, and the POSIX version already
has to have ifdeffery for different allocation functions.

Move to a single implementation in memalign.c, which uses the Windows
_aligned_malloc if we detect that function in meson.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220226180723.1706285-7-peter.maydell@linaro.org
---
 meson.build        |  1 +
 util/memalign.c    | 39 +++++++++++++++++++++++++++++++++++++++
 util/oslib-posix.c | 29 -----------------------------
 util/oslib-win32.c | 17 -----------------
 4 files changed, 40 insertions(+), 46 deletions(-)

Comments

Philippe Mathieu-Daudé March 4, 2022, 2:02 p.m. UTC | #1 
On 4/3/22 12:21, Peter Maydell wrote:
> The qemu_try_memalign() functions for POSIX and Windows used to be
> significantly different, but these days they are identical except for
> the actual allocation function called, and the POSIX version already
> has to have ifdeffery for different allocation functions.
> 
> Move to a single implementation in memalign.c, which uses the Windows
> _aligned_malloc if we detect that function in meson.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Message-id: 20220226180723.1706285-7-peter.maydell@linaro.org
> ---
>   meson.build        |  1 +
>   util/memalign.c    | 39 +++++++++++++++++++++++++++++++++++++++
>   util/oslib-posix.c | 29 -----------------------------
>   util/oslib-win32.c | 17 -----------------
>   4 files changed, 40 insertions(+), 46 deletions(-)

Nice.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Richard Henderson March 4, 2022, 8:20 p.m. UTC | #2 
On 3/4/22 01:21, Peter Maydell wrote:
> +     * platform APIs (for instance _alligned_malloc() will

Typo there with the 'll'.


r~
diff mbox series

Patch

diff --git a/meson.build b/meson.build
index 73fd17a0523..eae0e4febb3 100644
--- a/meson.build
+++ b/meson.build
@@ -1622,6 +1622,7 @@  config_host_data.set('CONFIG_POSIX_FALLOCATE', cc.has_function('posix_fallocate'
 # Note that we need to specify prefix: here to avoid incorrectly
 # thinking that Windows has posix_memalign()
 config_host_data.set('CONFIG_POSIX_MEMALIGN', cc.has_function('posix_memalign', prefix: '#include <stdlib.h>'))
+config_host_data.set('CONFIG_ALIGNED_MALLOC', cc.has_function('_aligned_malloc'))
 config_host_data.set('CONFIG_PPOLL', cc.has_function('ppoll'))
 config_host_data.set('CONFIG_PREADV', cc.has_function('preadv', prefix: '#include <sys/uio.h>'))
 config_host_data.set('CONFIG_SEM_TIMEDWAIT', cc.has_function('sem_timedwait', dependencies: threads))
diff --git a/util/memalign.c b/util/memalign.c
index 6dfc20abbb1..c3280528d24 100644
--- a/util/memalign.c
+++ b/util/memalign.c
@@ -25,6 +25,45 @@ 
  */
 
 #include "qemu/osdep.h"
+#include "qemu/host-utils.h"
+#include "trace.h"
+
+void *qemu_try_memalign(size_t alignment, size_t size)
+{
+    void *ptr;
+
+    if (alignment < sizeof(void*)) {
+        alignment = sizeof(void*);
+    } else {
+        g_assert(is_power_of_2(alignment));
+    }
+
+    /*
+     * Handling of 0 allocations varies among the different
+     * platform APIs (for instance _alligned_malloc() will
+     * fail) -- ensure that we always return a valid non-NULL
+     * pointer that can be freed by qemu_vfree().
+     */
+    if (size == 0) {
+        size++;
+    }
+#if defined(CONFIG_POSIX_MEMALIGN)
+    int ret;
+    ret = posix_memalign(&ptr, alignment, size);
+    if (ret != 0) {
+        errno = ret;
+        ptr = NULL;
+    }
+#elif defined(CONFIG_ALIGNED_MALLOC)
+    ptr = _aligned_malloc(size, alignment);
+#elif defined(CONFIG_BSD)
+    ptr = valloc(size);
+#else
+    ptr = memalign(alignment, size);
+#endif
+    trace_qemu_memalign(alignment, size, ptr);
+    return ptr;
+}
 
 void *qemu_memalign(size_t alignment, size_t size)
 {
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index f7e22f4ff9b..91798f7e504 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -199,35 +199,6 @@  fail_close:
     return false;
 }
 
-void *qemu_try_memalign(size_t alignment, size_t size)
-{
-    void *ptr;
-
-    if (alignment < sizeof(void*)) {
-        alignment = sizeof(void*);
-    } else {
-        g_assert(is_power_of_2(alignment));
-    }
-
-    if (size == 0) {
-        size++;
-    }
-#if defined(CONFIG_POSIX_MEMALIGN)
-    int ret;
-    ret = posix_memalign(&ptr, alignment, size);
-    if (ret != 0) {
-        errno = ret;
-        ptr = NULL;
-    }
-#elif defined(CONFIG_BSD)
-    ptr = valloc(size);
-#else
-    ptr = memalign(alignment, size);
-#endif
-    trace_qemu_memalign(alignment, size, ptr);
-    return ptr;
-}
-
 /* alloc shared memory pages */
 void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment, bool shared,
                           bool noreserve)
diff --git a/util/oslib-win32.c b/util/oslib-win32.c
index 8c28d70904d..d9768532bec 100644
--- a/util/oslib-win32.c
+++ b/util/oslib-win32.c
@@ -44,23 +44,6 @@ 
 /* this must come after including "trace.h" */
 #include <shlobj.h>
 
-void *qemu_try_memalign(size_t alignment, size_t size)
-{
-    void *ptr;
-
-    if (alignment < sizeof(void *)) {
-        alignment = sizeof(void *);
-    } else {
-        g_assert(is_power_of_2(alignment));
-    }
-    if (size == 0) {
-        size++;
-    }
-    ptr = _aligned_malloc(size, alignment);
-    trace_qemu_memalign(alignment, size, ptr);
-    return ptr;
-}
-
 static int get_allocation_granularity(void)
 {
     SYSTEM_INFO system_info;