diff options
Diffstat (limited to 'linux-uml/linux-uml-2.6.7/um-sysemu.patch')
| -rw-r--r-- | linux-uml/linux-uml-2.6.7/um-sysemu.patch | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/linux-uml/linux-uml-2.6.7/um-sysemu.patch b/linux-uml/linux-uml-2.6.7/um-sysemu.patch index e69de29bb2..c97dff2415 100644 --- a/linux-uml/linux-uml-2.6.7/um-sysemu.patch +++ b/linux-uml/linux-uml-2.6.7/um-sysemu.patch @@ -0,0 +1,145 @@ + +Turns off syscall emulation patch for ptrace (SYSEMU) on. +SYSEMU is a performance-patch introduced by Laurent Vivier. It changes +behaviour of ptrace() and helps reducing host context switch rate. +To make it working, you need a kernel patch for your host, too. +See http://perso.wanadoo.fr/laurent.vivier/UML/ for further information. + +Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade_spam@yahoo.it> +--- + + uml-linux-2.6.7-paolo/arch/um/kernel/process.c | 35 ++++++++++ + uml-linux-2.6.7-paolo/arch/um/kernel/skas/include/ptrace-skas.h | 7 ++ + uml-linux-2.6.7-paolo/arch/um/kernel/skas/process.c | 22 ++++++ + 3 files changed, 64 insertions(+) + +diff -puN arch/um/kernel/process.c~um-sysemu arch/um/kernel/process.c +--- uml-linux-2.6.7/arch/um/kernel/process.c~um-sysemu 2004-06-29 21:03:03.801059520 +0200 ++++ uml-linux-2.6.7-paolo/arch/um/kernel/process.c 2004-06-29 21:03:03.806058760 +0200 +@@ -19,6 +19,7 @@ + #include <asm/sigcontext.h> + #include <asm/unistd.h> + #include <asm/page.h> ++#include <asm/user.h> + #include "user_util.h" + #include "kern_util.h" + #include "user.h" +@@ -227,6 +228,40 @@ 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); ++ if(ptrace(PTRACE_SYSEMU, pid, 0, 0) >= 0) { ++ struct user_regs_struct regs; ++ ++ if (waitpid(pid, &status, WUNTRACED) < 0) ++ panic("check_ptrace : wait failed, errno = %d", errno); ++ if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP)) ++ panic("check_ptrace : expected SIGTRAP, " ++ "got status = %d", status); ++ ++ if (ptrace(PTRACE_GETREGS, pid, 0, ®s) < 0) ++ panic("check_ptrace : failed to read child " ++ "registers, errno = %d", errno); ++ regs.orig_eax = pid; ++ if (ptrace(PTRACE_SETREGS, pid, 0, ®s) < 0) ++ panic("check_ptrace : failed to modify child " ++ "registers, errno = %d", errno); ++ ++ stop_ptraced_child(pid, stack, 0); ++ ++ printk("OK\n"); ++ use_sysemu = 1; ++ } ++ else ++ { ++ printk("missing\n"); ++ stop_ptraced_child(pid, stack, 1); ++ } ++ ++# endif /* PTRACE_SYSEMU */ + } + + int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr) +diff -puN arch/um/kernel/skas/include/ptrace-skas.h~um-sysemu arch/um/kernel/skas/include/ptrace-skas.h +--- uml-linux-2.6.7/arch/um/kernel/skas/include/ptrace-skas.h~um-sysemu 2004-06-29 21:03:03.802059368 +0200 ++++ uml-linux-2.6.7-paolo/arch/um/kernel/skas/include/ptrace-skas.h 2004-06-29 21:03:03.806058760 +0200 +@@ -10,6 +10,13 @@ + + #ifdef UML_CONFIG_MODE_SKAS + ++/* syscall emulation path in ptrace */ ++ ++#ifndef PTRACE_SYSEMU ++#define PTRACE_SYSEMU 31 ++#endif ++extern int use_sysemu; ++ + #include "skas_ptregs.h" + + #define HOST_FRAME_SIZE 17 +diff -puN arch/um/kernel/skas/process.c~um-sysemu arch/um/kernel/skas/process.c +--- uml-linux-2.6.7/arch/um/kernel/skas/process.c~um-sysemu 2004-06-29 21:03:03.803059216 +0200 ++++ uml-linux-2.6.7-paolo/arch/um/kernel/skas/process.c 2004-06-29 21:03:03.806058760 +0200 +@@ -28,6 +28,10 @@ + #include "chan_user.h" + #include "signal_user.h" + ++#ifdef PTRACE_SYSEMU ++int use_sysemu = 0; ++#endif ++ + int is_skas_winch(int pid, int fd, void *data) + { + if(pid != getpid()) +@@ -68,6 +72,10 @@ static void handle_trap(int pid, union u + return; + } + ++#ifdef PTRACE_SYSEMU ++ if (!use_sysemu) ++ { ++#endif + err = ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET, __NR_getpid); + if(err < 0) + panic("handle_trap - nullifying syscall failed errno = %d\n", +@@ -82,6 +90,9 @@ static void handle_trap(int pid, union u + if((err < 0) || !WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP)) + panic("handle_trap - failed to wait at end of syscall, " + "errno = %d, status = %d\n", errno, status); ++#ifdef PTRACE_SYSEMU ++ } ++#endif + + handle_syscall(regs); + } +@@ -139,6 +150,11 @@ void userspace(union uml_pt_regs *regs) + + restore_registers(regs); + ++#ifdef PTRACE_SYSEMU ++ if (use_sysemu) ++ err = ptrace(PTRACE_SYSEMU, pid, 0, 0); ++ else ++#endif + err = ptrace(PTRACE_SYSCALL, pid, 0, 0); + if(err) + panic("userspace - PTRACE_SYSCALL failed, errno = %d\n", +@@ -177,6 +193,12 @@ void userspace(union uml_pt_regs *regs) + + restore_registers(regs); + ++#ifdef PTRACE_SYSEMU ++ if (use_sysemu) ++ op = singlestepping_skas() ? PTRACE_SINGLESTEP : ++ PTRACE_SYSEMU; ++ else ++#endif + op = singlestepping_skas() ? PTRACE_SINGLESTEP : + PTRACE_SYSCALL; + err = ptrace(op, pid, 0, 0); +_ |