qemu-arm
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PATCH v1 3/4] accel/tcg: only USE_STATIC_CODE_GEN_BUFFER on 32 bit


From: Niek Linnenbank
Subject: Re: [PATCH v1 3/4] accel/tcg: only USE_STATIC_CODE_GEN_BUFFER on 32 bit hosts
Date: Thu, 27 Feb 2020 20:20:14 +0100



On Wed, Feb 26, 2020 at 7:12 PM Alex Bennée <address@hidden> wrote:
There is no particular reason to use a static codegen buffer on 64 bit
hosts as we have address space to burn. Allow the common CONFIG_USER
case to use the mmap'ed buffers like SoftMMU.

Signed-off-by: Alex Bennée <address@hidden>
---
 accel/tcg/translate-all.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
index 5b66af783b5..4ce5d1b3931 100644
--- a/accel/tcg/translate-all.c
+++ b/accel/tcg/translate-all.c
@@ -892,11 +892,12 @@ static void page_lock_pair(PageDesc **ret_p1, tb_page_addr_t phys1,
     }
 }

-#if defined(CONFIG_USER_ONLY)
-/* Currently it is not recommended to allocate big chunks of data in
-   user mode. It will change when a dedicated libc will be used.  */
-/* ??? 64-bit hosts ought to have no problem mmaping data outside the
-   region in which the guest needs to run.  Revisit this.  */
+#if defined(CONFIG_USER_ONLY) && TCG_TARGET_REG_BITS == 32
+/*
+ * For user mode on smaller 32 bit systems we may run into trouble
+ * allocating big chunks of data in the right place. On these systems
+ * we utilise a static code generation buffer directly in the binary.
+ */
 #define USE_STATIC_CODE_GEN_BUFFER
 #endif

--
2.20.1


Reviewed-by: Niek Linnenbank <address@hidden>

--
Niek Linnenbank


reply via email to

[Prev in Thread] Current Thread [Next in Thread]