diff options
Diffstat (limited to 'linux-uml/linux-uml-2.6.7/sysemu_cmdParam.patch')
| -rw-r--r-- | linux-uml/linux-uml-2.6.7/sysemu_cmdParam.patch | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/linux-uml/linux-uml-2.6.7/sysemu_cmdParam.patch b/linux-uml/linux-uml-2.6.7/sysemu_cmdParam.patch index e69de29bb2..2422867a17 100644 --- a/linux-uml/linux-uml-2.6.7/sysemu_cmdParam.patch +++ b/linux-uml/linux-uml-2.6.7/sysemu_cmdParam.patch @@ -0,0 +1,67 @@ + +Adds the "nosysemu" command line parameter to disable SYSEMU + +Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade_spam@yahoo.it> +--- + + uml-linux-2.6.7-paolo/arch/um/kernel/process.c | 26 +++++++++++++++++++++---- + 1 files changed, 22 insertions(+), 4 deletions(-) + +diff -puN arch/um/kernel/process.c~sysemu_cmdParam arch/um/kernel/process.c +--- uml-linux-2.6.7/arch/um/kernel/process.c~sysemu_cmdParam 2004-06-29 21:03:04.131009360 +0200 ++++ uml-linux-2.6.7-paolo/arch/um/kernel/process.c 2004-06-29 21:03:04.134008904 +0200 +@@ -196,6 +196,22 @@ static void stop_ptraced_child(int pid, + panic("check_ptrace : munmap failed, errno = %d", errno); + } + ++static int force_sysemu_disabled = 0; ++ ++static int __init nosysemu_cmd_param(char *str, int* add) ++{ ++ force_sysemu_disabled = 1; ++ return 0; ++} ++ ++__uml_setup("nosysemu", nosysemu_cmd_param, ++ "nosysemu\n" ++ " Turns off syscall emulation patch for ptrace (SYSEMU) on.\n" ++ " SYSEMU is a performance-patch introduced by Laurent Vivier. It changes\n" ++ " behaviour of ptrace() and helps reducing host context switch rate.\n" ++ " To make it working, you need a kernel patch for your host, too.\n" ++ " See http://perso.wanadoo.fr/laurent.vivier/UML/ for further information.\n"); ++ + void __init check_ptrace(void) + { + void *stack; +@@ -229,7 +245,6 @@ void __init check_ptrace(void) + stop_ptraced_child(pid, stack, 0); + printk("OK\n"); + +-#ifdef PTRACE_SYSEMU + printk("Checking syscall emulation patch for ptrace..."); + use_sysemu = 0; + pid = start_ptraced_child(&stack); +@@ -252,8 +267,12 @@ void __init check_ptrace(void) + + stop_ptraced_child(pid, stack, 0); + +- printk("OK\n"); +- use_sysemu = 1; ++ if (!force_sysemu_disabled) { ++ printk("found\n"); ++ use_sysemu = 1; ++ } else { ++ printk("found but disabled\n"); ++ } + } + else + { +@@ -261,7 +280,6 @@ void __init check_ptrace(void) + stop_ptraced_child(pid, stack, 1); + } + +-# endif /* PTRACE_SYSEMU */ + } + + int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr) +_ |