| Message ID | 20230411133004.2268170-2-josimmon@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | x86_64: aarch64: Set call number just before syscall | expand |
On Tue, Apr 11, 2023 at 8:32 AM Joe Simmons-Talbott via Libc-alpha < libc-alpha@sourceware.org> wrote: > > To make identifying syscalls easier during call tree analysis load the > syscall number just before performing the syscall. > --- > sysdeps/unix/sysv/linux/x86_64/sysdep.h | 33 +++++++++++++++++++++++++ > 1 file changed, 33 insertions(+) > > diff --git a/sysdeps/unix/sysv/linux/x86_64/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/sysdep.h > index cfb51be8c5..800a56723f 100644 > --- a/sysdeps/unix/sysv/linux/x86_64/sysdep.h > +++ b/sysdeps/unix/sysv/linux/x86_64/sysdep.h > @@ -250,12 +250,20 @@ > (long int) resultvar; \ > }) > > +#define MSTR_HELPER(x) #x > +#define MSTR(x) MSTR_HELPER(x) > + > #undef internal_syscall1 > #define internal_syscall1(number, arg1) \ > ({ \ > unsigned long int resultvar; \ > TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > + if (__builtin_constant_p(number)) \ > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > + : /* no outputs */ \ > + : "i" (number) \ > + : "eax"); \ > asm volatile ( \ > "syscall\n\t" \ > : "=a" (resultvar) \ > @@ -272,6 +280,11 @@ > TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > + if (__builtin_constant_p(number)) \ > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > + : /* no outputs */ \ > + : "i" (number) \ > + : "eax"); \ Is it ever possible for another instruction to be re-ordered between setting `eax` and the `syscall`? > asm volatile ( \ > "syscall\n\t" \ > : "=a" (resultvar) \ > @@ -290,6 +303,11 @@ > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > + if (__builtin_constant_p(number)) \ > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > + : /* no outputs */ \ > + : "i" (number) \ > + : "eax"); \ > asm volatile ( \ > "syscall\n\t" \ > : "=a" (resultvar) \ > @@ -310,6 +328,11 @@ > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > + if (__builtin_constant_p(number)) \ > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > + : /* no outputs */ \ > + : "i" (number) \ > + : "eax"); \ > asm volatile ( \ > "syscall\n\t" \ > : "=a" (resultvar) \ > @@ -332,6 +355,11 @@ > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > + if (__builtin_constant_p(number)) \ > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > + : /* no outputs */ \ > + : "i" (number) \ > + : "eax"); \ > asm volatile ( \ > "syscall\n\t" \ > : "=a" (resultvar) \ > @@ -357,6 +385,11 @@ > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > + if (__builtin_constant_p(number)) \ > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > + : /* no outputs */ \ > + : "i" (number) \ > + : "eax"); \ > asm volatile ( \ > "syscall\n\t" \ > : "=a" (resultvar) \ > -- > 2.39.2 >
On Mon, Apr 17, 2023 at 5:35 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote: > > > > On Tue, Apr 11, 2023 at 8:32 AM Joe Simmons-Talbott via Libc-alpha <libc-alpha@sourceware.org> wrote: > > > > To make identifying syscalls easier during call tree analysis load the > > syscall number just before performing the syscall. > > --- > > sysdeps/unix/sysv/linux/x86_64/sysdep.h | 33 +++++++++++++++++++++++++ > > 1 file changed, 33 insertions(+) > > > > diff --git a/sysdeps/unix/sysv/linux/x86_64/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/sysdep.h > > index cfb51be8c5..800a56723f 100644 > > --- a/sysdeps/unix/sysv/linux/x86_64/sysdep.h > > +++ b/sysdeps/unix/sysv/linux/x86_64/sysdep.h > > @@ -250,12 +250,20 @@ > > (long int) resultvar; \ > > }) > > > > +#define MSTR_HELPER(x) #x > > +#define MSTR(x) MSTR_HELPER(x) > > + > > #undef internal_syscall1 > > #define internal_syscall1(number, arg1) \ > > ({ \ > > unsigned long int resultvar; \ > > TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ > > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > > + if (__builtin_constant_p(number)) \ > > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > > + : /* no outputs */ \ > > + : "i" (number) \ > > + : "eax"); \ > > asm volatile ( \ > > "syscall\n\t" \ > > : "=a" (resultvar) \ > > @@ -272,6 +280,11 @@ > > TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ > > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > > + if (__builtin_constant_p(number)) \ > > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > > + : /* no outputs */ \ > > + : "i" (number) \ > > + : "eax"); \ > Is it ever possible for another instruction to be re-ordered between setting > `eax` and the `syscall`? nevermind, you addressed in V2. > > asm volatile ( \ > > "syscall\n\t" \ > > : "=a" (resultvar) \ > > @@ -290,6 +303,11 @@ > > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > > + if (__builtin_constant_p(number)) \ > > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > > + : /* no outputs */ \ > > + : "i" (number) \ > > + : "eax"); \ > > asm volatile ( \ > > "syscall\n\t" \ > > : "=a" (resultvar) \ > > @@ -310,6 +328,11 @@ > > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > > + if (__builtin_constant_p(number)) \ > > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > > + : /* no outputs */ \ > > + : "i" (number) \ > > + : "eax"); \ > > asm volatile ( \ > > "syscall\n\t" \ > > : "=a" (resultvar) \ > > @@ -332,6 +355,11 @@ > > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > > + if (__builtin_constant_p(number)) \ > > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > > + : /* no outputs */ \ > > + : "i" (number) \ > > + : "eax"); \ > > asm volatile ( \ > > "syscall\n\t" \ > > : "=a" (resultvar) \ > > @@ -357,6 +385,11 @@ > > register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ > > register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ > > register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ > > + if (__builtin_constant_p(number)) \ > > + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ > > + : /* no outputs */ \ > > + : "i" (number) \ > > + : "eax"); \ > > asm volatile ( \ > > "syscall\n\t" \ > > : "=a" (resultvar) \ > > -- > > 2.39.2 > >
diff --git a/sysdeps/unix/sysv/linux/x86_64/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/sysdep.h index cfb51be8c5..800a56723f 100644 --- a/sysdeps/unix/sysv/linux/x86_64/sysdep.h +++ b/sysdeps/unix/sysv/linux/x86_64/sysdep.h @@ -250,12 +250,20 @@ (long int) resultvar; \ }) +#define MSTR_HELPER(x) #x +#define MSTR(x) MSTR_HELPER(x) + #undef internal_syscall1 #define internal_syscall1(number, arg1) \ ({ \ unsigned long int resultvar; \ TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ + if (__builtin_constant_p(number)) \ + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ + : /* no outputs */ \ + : "i" (number) \ + : "eax"); \ asm volatile ( \ "syscall\n\t" \ : "=a" (resultvar) \ @@ -272,6 +280,11 @@ TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ + if (__builtin_constant_p(number)) \ + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ + : /* no outputs */ \ + : "i" (number) \ + : "eax"); \ asm volatile ( \ "syscall\n\t" \ : "=a" (resultvar) \ @@ -290,6 +303,11 @@ register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ + if (__builtin_constant_p(number)) \ + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ + : /* no outputs */ \ + : "i" (number) \ + : "eax"); \ asm volatile ( \ "syscall\n\t" \ : "=a" (resultvar) \ @@ -310,6 +328,11 @@ register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ + if (__builtin_constant_p(number)) \ + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ + : /* no outputs */ \ + : "i" (number) \ + : "eax"); \ asm volatile ( \ "syscall\n\t" \ : "=a" (resultvar) \ @@ -332,6 +355,11 @@ register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ + if (__builtin_constant_p(number)) \ + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ + : /* no outputs */ \ + : "i" (number) \ + : "eax"); \ asm volatile ( \ "syscall\n\t" \ : "=a" (resultvar) \ @@ -357,6 +385,11 @@ register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ + if (__builtin_constant_p(number)) \ + asm volatile ("movl $" MSTR(number) ", %%eax\n\t" \ + : /* no outputs */ \ + : "i" (number) \ + : "eax"); \ asm volatile ( \ "syscall\n\t" \ : "=a" (resultvar) \