[PATCH v5 0/2] util/oslib: qemu_try_memalign() improvements

[PATCH v5 0/2] util/oslib: qemu_try_memalign() improvements

[Philippe Mathieu-Daudé]

- Use _aligned_malloc for qemu_try_memalign on win32
- Assert qemu_try_memalign() alignment is a power of 2

Since v4:
- Drop superfluous assert (Richard)

Philippe Mathieu-Daudé (1):
  util/oslib: Assert qemu_try_memalign() alignment is a power of 2

Richard Henderson (1):
  util/oslib-win32: Use _aligned_malloc for qemu_try_memalign

 util/oslib-posix.c |  2 ++
 util/oslib-win32.c | 12 +++++-------
 2 files changed, 7 insertions(+), 7 deletions(-)

-- 
2.26.2

[PATCH v5 1/2] util/oslib-win32: Use _aligned_malloc for qemu_try_memalign

[Philippe Mathieu-Daudé]

From: Richard Henderson <richard.henderson@linaro.org>

We do not need or want to be allocating page sized quanta.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-Id: <20201018164836.1149452-1-richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 util/oslib-win32.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/util/oslib-win32.c b/util/oslib-win32.c
index e99debfb8dd..29dd05d59d7 100644
--- a/util/oslib-win32.c
+++ b/util/oslib-win32.c
@@ -39,6 +39,7 @@
 #include "trace.h"
 #include "qemu/sockets.h"
 #include "qemu/cutils.h"
+#include <malloc.h>
 
 /* this must come after including "trace.h" */
 #include <shlobj.h>
@@ -56,10 +57,8 @@ void *qemu_try_memalign(size_t alignment, size_t size)
 {
     void *ptr;
 
-    if (!size) {
-        abort();
-    }
-    ptr = VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
+    g_assert(size != 0);
+    ptr = _aligned_malloc(alignment, size);
     trace_qemu_memalign(alignment, size, ptr);
     return ptr;
 }
@@ -93,9 +92,7 @@ void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared)
 void qemu_vfree(void *ptr)
 {
     trace_qemu_vfree(ptr);
-    if (ptr) {
-        VirtualFree(ptr, 0, MEM_RELEASE);
-    }
+    _aligned_free(ptr);
 }
 
 void qemu_anon_ram_free(void *ptr, size_t size)
-- 
2.26.2

[PATCH v5 2/2] util/oslib: Assert qemu_try_memalign() alignment is a power of 2

[Philippe Mathieu-Daudé]

qemu_try_memalign() expects a power of 2 alignment:

- posix_memalign(3):

  The address of the allocated memory will be a multiple of alignment,
  which must be a power of two and a multiple of sizeof(void *).

- _aligned_malloc()

  The alignment value, which must be an integer power of 2.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 util/oslib-posix.c | 2 ++
 util/oslib-win32.c | 1 +
 2 files changed, 3 insertions(+)

diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index f15234b5c03..3e022d7206b 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -200,6 +200,8 @@ void *qemu_try_memalign(size_t alignment, size_t size)
 
     if (alignment < sizeof(void*)) {
         alignment = sizeof(void*);
+    } else {
+        g_assert(is_power_of_2(alignment));
     }
 
 #if defined(CONFIG_POSIX_MEMALIGN)
diff --git a/util/oslib-win32.c b/util/oslib-win32.c
index 29dd05d59d7..72e4ee910ce 100644
--- a/util/oslib-win32.c
+++ b/util/oslib-win32.c
@@ -58,6 +58,7 @@ void *qemu_try_memalign(size_t alignment, size_t size)
     void *ptr;
 
     g_assert(size != 0);
+    g_assert(is_power_of_2(alignment));
     ptr = _aligned_malloc(alignment, size);
     trace_qemu_memalign(alignment, size, ptr);
     return ptr;
-- 
2.26.2

Re: [PATCH v5 0/2] util/oslib: qemu_try_memalign() improvements

[Richard Henderson]

On 10/21/20 12:38 PM, Philippe Mathieu-Daudé wrote:
> - Use _aligned_malloc for qemu_try_memalign on win32
> - Assert qemu_try_memalign() alignment is a power of 2
> 
> Since v4:
> - Drop superfluous assert (Richard)
> 
> Philippe Mathieu-Daudé (1):
>   util/oslib: Assert qemu_try_memalign() alignment is a power of 2
> 
> Richard Henderson (1):
>   util/oslib-win32: Use _aligned_malloc for qemu_try_memalign
> 
>  util/oslib-posix.c |  2 ++
>  util/oslib-win32.c | 12 +++++-------
>  2 files changed, 7 insertions(+), 7 deletions(-)
> 

Ping.


r~

Re: [PATCH v5 0/2] util/oslib: qemu_try_memalign() improvements

[Richard Henderson]

On 12/16/20 9:24 AM, Richard Henderson wrote:
> On 10/21/20 12:38 PM, Philippe Mathieu-Daudé wrote:
>> - Use _aligned_malloc for qemu_try_memalign on win32
>> - Assert qemu_try_memalign() alignment is a power of 2
>>
>> Since v4:
>> - Drop superfluous assert (Richard)
>>
>> Philippe Mathieu-Daudé (1):
>>   util/oslib: Assert qemu_try_memalign() alignment is a power of 2
>>
>> Richard Henderson (1):
>>   util/oslib-win32: Use _aligned_malloc for qemu_try_memalign
>>
>>  util/oslib-posix.c |  2 ++
>>  util/oslib-win32.c | 12 +++++-------
>>  2 files changed, 7 insertions(+), 7 deletions(-)
>>
> 
> Ping.

Ping2.  Shall I just queue this to tcg-next?


r~

Re: [PATCH v5 0/2] util/oslib: qemu_try_memalign() improvements

[Paolo Bonzini]

On 05/01/21 01:06, Richard Henderson wrote:
> On 12/16/20 9:24 AM, Richard Henderson wrote:
>> On 10/21/20 12:38 PM, Philippe Mathieu-Daudé wrote:
>>> - Use _aligned_malloc for qemu_try_memalign on win32
>>> - Assert qemu_try_memalign() alignment is a power of 2
>>>
>>> Since v4:
>>> - Drop superfluous assert (Richard)
>>>
>>> Philippe Mathieu-Daudé (1):
>>>    util/oslib: Assert qemu_try_memalign() alignment is a power of 2
>>>
>>> Richard Henderson (1):
>>>    util/oslib-win32: Use _aligned_malloc for qemu_try_memalign
>>>
>>>   util/oslib-posix.c |  2 ++
>>>   util/oslib-win32.c | 12 +++++-------
>>>   2 files changed, 7 insertions(+), 7 deletions(-)
>>>
>>
>> Ping.
> 
> Ping2.  Shall I just queue this to tcg-next?

Yes, just go ahead.  util/ is everybody's land, maintainers are supposed 
to know what they're doing. :)

Paolo