Changeset d7365604 in mainline for uspace/lib/libc/arch/ia32/src

Timestamp:

2009-10-22T17:45:31Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

af6cad4

Parents:

50989793 (diff), 5328d63 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge support for SYSENTER autodetection.

Location:

uspace/lib/libc/arch/ia32/src

Files:

• entry.s (modified) (3 diffs)
• syscall.S (modified) (3 diffs)

uspace/lib/libc/arch/ia32/src/entry.s

@@ -27 +27 @@
 #
 
+INTEL_CPUID_STANDARD = 1
+INTEL_SEP = 11
+
 .section .init, "ax"
 
@@ -35 +38 @@
 ## User-space task entry point
 #
-# %ebx contains the PCB pointer
+# %edi contains the PCB pointer
 #
 __entry:
@@ -44 +47 @@
         # Do not set %gs, it contains descriptor that can see TLS
 
+        # Detect the mechanism used for making syscalls
+        movl $(INTEL_CPUID_STANDARD), %eax
+        cpuid
+        bt $(INTEL_SEP), %edx
+        jnc 0f
+        leal __syscall_fast_func, %eax
+        movl $__syscall_fast, (%eax)
+0:
+
         # Pass the PCB pointer to __main as the first argument
-        pushl %ebx
+        pushl %edi
         call __main
 

uspace/lib/libc/arch/ia32/src/syscall.S

@@ -27 +27 @@
 #
 
+.data
+
+.global __syscall_fast_func
+__syscall_fast_func:
+        .long __syscall_slow
+
 .text
 
@@ -35 +41 @@
  * could benefit from this and not save unused registers on the stack.
  */
-.global __syscall_int
-__syscall_int:
+.global __syscall_slow
+__syscall_slow:
         pushl %ebx
         pushl %esi
@@ -64 +70 @@
  * segment, otherwise the SYSENTER wouldn't work in the first place).
  */
-.global __syscall_sysenter
-__syscall_sysenter:
+.global __syscall_fast
+__syscall_fast:
         pushl %ebx
         pushl %esi