Wire up the rseq system call on 32-bit ARM. This provides an ABI improving the speed of a user-space getcpu operation on ARM by skipping the getcpu system call on the fast path, as well as improving the speed of user-space operations on per-cpu data compared to using load-linked/store-conditional. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> CC: Russell King <linux@xxxxxxxxxxxxxxxx> CC: Catalin Marinas <catalin.marinas@xxxxxxx> CC: Will Deacon <will.deacon@xxxxxxx> CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CC: Paul Turner <pjt@xxxxxxxxxx> CC: Andrew Hunter <ahh@xxxxxxxxxx> CC: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CC: Andy Lutomirski <luto@xxxxxxxxxxxxxx> CC: Andi Kleen <andi@xxxxxxxxxxxxxx> CC: Dave Watson <davejwatson@xxxxxx> CC: Chris Lameter <cl@xxxxxxxxx> CC: Ingo Molnar <mingo@xxxxxxxxxx> CC: Ben Maurer <bmaurer@xxxxxx> CC: Steven Rostedt <rostedt@xxxxxxxxxxx> CC: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> CC: Josh Triplett <josh@xxxxxxxxxxxxxxxx> CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> CC: Boqun Feng <boqun.feng@xxxxxxxxx> CC: linux-api@xxxxxxxxxxxxxxx --- arch/arm/include/uapi/asm/unistd.h | 1 + arch/arm/kernel/calls.S | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/arm/include/uapi/asm/unistd.h b/arch/arm/include/uapi/asm/unistd.h index 2cb9dc7..8f61c79 100644 --- a/arch/arm/include/uapi/asm/unistd.h +++ b/arch/arm/include/uapi/asm/unistd.h @@ -420,6 +420,7 @@ #define __NR_copy_file_range (__NR_SYSCALL_BASE+391) #define __NR_preadv2 (__NR_SYSCALL_BASE+392) #define __NR_pwritev2 (__NR_SYSCALL_BASE+393) +#define __NR_rseq (__NR_SYSCALL_BASE+394) /* * The following SWIs are ARM private. diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S index 703fa0f..0865c04 100644 --- a/arch/arm/kernel/calls.S +++ b/arch/arm/kernel/calls.S @@ -403,6 +403,7 @@ CALL(sys_copy_file_range) CALL(sys_preadv2) CALL(sys_pwritev2) + CALL(sys_rseq) #ifndef syscalls_counted .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls #define syscalls_counted -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
