diff options
| author | Jan Beulich <jbeulich@novell.com> | 2006-12-07 02:14:02 +0100 |
|---|---|---|
| committer | Andi Kleen <andi@basil.nowhere.org> | 2006-12-07 02:14:02 +0100 |
| commit | bcddc0155f351ab3f06c6ede6d91fd399ef9e18f (patch) | |
| tree | e3ba814c9cb319f6e486aea8e0fe537177f9594f /arch/x86_64 | |
| parent | da68933e0a999fb13636653c710cca701b457ad2 (diff) | |
[PATCH] x86-64: miscellaneous entry.S adjustments
This patch:
- makes ret_from_sys_call no longer global (all external users were
previously switched to use int_ret_from_sys_call)
- adjusts placement of a CFI_{REMEMBER,RESTORE}_STATE pair to better
fit logic flow
- eliminates an unnecessary pair of CFI_{REMEMBER,RESTORE}_STATE
- glues together function- and unwinder-wise the previously separate
system_call and int_ret_from_sys_call function fragments
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Diffstat (limited to 'arch/x86_64')
| -rw-r--r-- | arch/x86_64/kernel/entry.S | 36 |
1 files changed, 6 insertions, 30 deletions
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 7d401b00d82..601d332c4b7 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -230,7 +230,6 @@ ENTRY(system_call) CFI_REL_OFFSET rip,RIP-ARGOFFSET GET_THREAD_INFO(%rcx) testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),threadinfo_flags(%rcx) - CFI_REMEMBER_STATE jnz tracesys cmpq $__NR_syscall_max,%rax ja badsys @@ -241,7 +240,6 @@ ENTRY(system_call) * Syscall return path ending with SYSRET (fast path) * Has incomplete stack frame and undefined top of stack. */ - .globl ret_from_sys_call ret_from_sys_call: movl $_TIF_ALLWORK_MASK,%edi /* edi: flagmask */ @@ -251,8 +249,8 @@ sysret_check: TRACE_IRQS_OFF movl threadinfo_flags(%rcx),%edx andl %edi,%edx - CFI_REMEMBER_STATE jnz sysret_careful + CFI_REMEMBER_STATE /* * sysretq will re-enable interrupts: */ @@ -265,10 +263,10 @@ sysret_check: swapgs sysretq + CFI_RESTORE_STATE /* Handle reschedules */ /* edx: work, edi: workmask */ sysret_careful: - CFI_RESTORE_STATE bt $TIF_NEED_RESCHED,%edx jnc sysret_signal TRACE_IRQS_ON @@ -306,7 +304,6 @@ badsys: /* Do syscall tracing */ tracesys: - CFI_RESTORE_STATE SAVE_REST movq $-ENOSYS,RAX(%rsp) FIXUP_TOP_OF_STACK %rdi @@ -322,32 +319,13 @@ tracesys: call *sys_call_table(,%rax,8) 1: movq %rax,RAX-ARGOFFSET(%rsp) /* Use IRET because user could have changed frame */ - jmp int_ret_from_sys_call - CFI_ENDPROC -END(system_call) /* * Syscall return path ending with IRET. * Has correct top of stack, but partial stack frame. - */ -ENTRY(int_ret_from_sys_call) - CFI_STARTPROC simple - CFI_SIGNAL_FRAME - CFI_DEF_CFA rsp,SS+8-ARGOFFSET - /*CFI_REL_OFFSET ss,SS-ARGOFFSET*/ - CFI_REL_OFFSET rsp,RSP-ARGOFFSET - /*CFI_REL_OFFSET rflags,EFLAGS-ARGOFFSET*/ - /*CFI_REL_OFFSET cs,CS-ARGOFFSET*/ - CFI_REL_OFFSET rip,RIP-ARGOFFSET - CFI_REL_OFFSET rdx,RDX-ARGOFFSET - CFI_REL_OFFSET rcx,RCX-ARGOFFSET - CFI_REL_OFFSET rax,RAX-ARGOFFSET - CFI_REL_OFFSET rdi,RDI-ARGOFFSET - CFI_REL_OFFSET rsi,RSI-ARGOFFSET - CFI_REL_OFFSET r8,R8-ARGOFFSET - CFI_REL_OFFSET r9,R9-ARGOFFSET - CFI_REL_OFFSET r10,R10-ARGOFFSET - CFI_REL_OFFSET r11,R11-ARGOFFSET + */ + .globl int_ret_from_sys_call +int_ret_from_sys_call: cli TRACE_IRQS_OFF testl $3,CS-ARGOFFSET(%rsp) @@ -394,8 +372,6 @@ int_very_careful: popq %rdi CFI_ADJUST_CFA_OFFSET -8 andl $~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edi - cli - TRACE_IRQS_OFF jmp int_restore_rest int_signal: @@ -411,7 +387,7 @@ int_restore_rest: TRACE_IRQS_OFF jmp int_with_check CFI_ENDPROC -END(int_ret_from_sys_call) +END(system_call) /* * Certain special system calls that need to save a complete full stack frame. |