Wire up the thread-local ABI system call on x86 32/64.

This provides an ABI improving the speed of a getcpu operation
on x86 by removing the need to perform a function call, "lsl"
instruction, or system call on the fast path.

The thread-local ABI can be extended to add features in the future.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
CC: Russell King <li...@arm.linux.org.uk>
CC: Catalin Marinas <catalin.mari...@arm.com>
CC: Will Deacon <will.dea...@arm.com>
CC: Thomas Gleixner <t...@linutronix.de>
CC: Paul Turner <p...@google.com>
CC: Andrew Hunter <a...@google.com>
CC: Peter Zijlstra <pet...@infradead.org>
CC: Andy Lutomirski <l...@amacapital.net>
CC: Andi Kleen <a...@firstfloor.org>
CC: Dave Watson <davejwat...@fb.com>
CC: Chris Lameter <c...@linux.com>
CC: Ingo Molnar <mi...@redhat.com>
CC: "H. Peter Anvin" <h...@zytor.com>
CC: Ben Maurer <bmau...@fb.com>
CC: Steven Rostedt <rost...@goodmis.org>
CC: "Paul E. McKenney" <paul...@linux.vnet.ibm.com>
CC: Josh Triplett <j...@joshtriplett.org>
CC: Linus Torvalds <torva...@linux-foundation.org>
CC: Andrew Morton <a...@linux-foundation.org>
CC: Boqun Feng <boqun.f...@gmail.com>
CC: linux-...@vger.kernel.org
---
 arch/x86/entry/syscalls/syscall_32.tbl | 1 +
 arch/x86/entry/syscalls/syscall_64.tbl | 1 +
 2 files changed, 2 insertions(+)

diff --git a/arch/x86/entry/syscalls/syscall_32.tbl 
b/arch/x86/entry/syscalls/syscall_32.tbl
index cb713df..e31d5a5 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -384,3 +384,4 @@
 375    i386    membarrier              sys_membarrier
 376    i386    mlock2                  sys_mlock2
 377    i386    copy_file_range         sys_copy_file_range
+378    i386    thread_local_abi        sys_thread_local_abi
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl 
b/arch/x86/entry/syscalls/syscall_64.tbl
index dc1040a..6aaddb4b 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -333,6 +333,7 @@
 324    common  membarrier              sys_membarrier
 325    common  mlock2                  sys_mlock2
 326    common  copy_file_range         sys_copy_file_range
+326    common  thread_local_abi        sys_thread_local_abi
 
 #
 # x32-specific system call numbers start at 512 to avoid cache impact
-- 
2.1.4

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