[Patch v4 12/18] x86: Group thread info flags by functionality

From: Tim Chen
Date: Tue Oct 30 2018 - 15:22:49 EST


The thread info flags are currently randomly distributed in the header
file arch/x86/include/asm/thread_info.h.

This patch groups the TIF flags according to these functionalities:
operation mode, syscall mode, pending work, task status and security
status.

Signed-off-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/thread_info.h | 93 ++++++++++++++++++++++----------------
1 file changed, 54 insertions(+), 39 deletions(-)

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 523c69e..60798a0 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -74,58 +74,73 @@ struct thread_info {
* - these are process state flags that various assembly files
* may need to access
*/
-#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
-#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
-#define TIF_SIGPENDING 2 /* signal pending */
-#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
-#define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/
-#define TIF_SSBD 5 /* Speculative store bypass disable */
-#define TIF_SYSCALL_EMU 6 /* syscall emulation active */
-#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
-#define TIF_SECCOMP 8 /* secure computing */
-#define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */
-#define TIF_UPROBE 12 /* breakpointed or singlestepping */
-#define TIF_PATCH_PENDING 13 /* pending live patching update */
-#define TIF_NOCPUID 15 /* CPUID is not accessible in userland */
-#define TIF_NOTSC 16 /* TSC is not accessible in userland */
-#define TIF_IA32 17 /* IA32 compatibility process */
-#define TIF_NOHZ 19 /* in adaptive nohz mode */
-#define TIF_MEMDIE 20 /* is terminating due to OOM killer */
-#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */
-#define TIF_IO_BITMAP 22 /* uses I/O bitmap */
-#define TIF_FORCED_TF 24 /* true if TF in eflags artificially */
-#define TIF_BLOCKSTEP 25 /* set when we want DEBUGCTLMSR_BTF */
-#define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */
-#define TIF_SYSCALL_TRACEPOINT 28 /* syscall tracepoint instrumentation */
-#define TIF_ADDR32 29 /* 32-bit address space on 64 bits */
-#define TIF_X32 30 /* 32-bit native x86-64 binary */
-#define TIF_FSCHECK 31 /* Check FS is USER_DS on return */
+
+/* Operation mode */
+#define TIF_NOCPUID 0 /* CPUID is not accessible in userland */
+#define TIF_NOTSC 1 /* TSC is not accessible in userland */
+#define TIF_IA32 2 /* IA32 compatibility process */
+#define TIF_NOHZ 3 /* In adaptive nohz mode */
+#define TIF_ADDR32 4 /* 32-bit address space on 64 bits */
+#define TIF_X32 5 /* 32-bit native x86-64 binary */
+
+/* Syscall mode */
+#define TIF_SYSCALL_TRACE 6 /* Syscall trace active */
+#define TIF_SYSCALL_EMU 7 /* Syscall emulation active */
+#define TIF_SYSCALL_AUDIT 8 /* Syscall auditing active */
+#define TIF_SYSCALL_TRACEPOINT 9 /* Syscall tracepoint instrumentation */
+
+/* Pending work */
+#define TIF_NOTIFY_RESUME 10 /* Callback before returning to user */
+#define TIF_SIGPENDING 11 /* Signal pending */
+#define TIF_NEED_RESCHED 12 /* Rescheduling necessary */
+#define TIF_SINGLESTEP 13 /* Reenable singlestep on user return*/
+#define TIF_USER_RETURN_NOTIFY 14 /* Notify kernel of userspace return */
+#define TIF_PATCH_PENDING 15 /* Pending live patching update */
+#define TIF_FSCHECK 16 /* Check FS is USER_DS on return */
+
+/* Task status */
+#define TIF_UPROBE 18 /* Breakpointed or singlestepping */
+#define TIF_MEMDIE 19 /* Is terminating due to OOM killer */
+#define TIF_POLLING_NRFLAG 20 /* Idle is polling for TIF_NEED_RESCHED */
+#define TIF_IO_BITMAP 21 /* Uses I/O bitmap */
+#define TIF_FORCED_TF 22 /* True if TF in eflags artificially */
+#define TIF_BLOCKSTEP 23 /* Set when we want DEBUGCTLMSR_BTF */
+#define TIF_LAZY_MMU_UPDATES 24 /* Task is updating the mmu lazily */
+
+/* Security mode */
+#define TIF_SECCOMP 25 /* Secure computing */
+#define TIF_SSBD 26 /* Speculative store bypass disable */
+
+#define _TIF_NOCPUID (1 << TIF_NOCPUID)
+#define _TIF_NOTSC (1 << TIF_NOTSC)
+#define _TIF_IA32 (1 << TIF_IA32)
+#define _TIF_NOHZ (1 << TIF_NOHZ)
+#define _TIF_ADDR32 (1 << TIF_ADDR32)
+#define _TIF_X32 (1 << TIF_X32)

#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
+#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
+#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
+#define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT)
+
#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
-#define _TIF_SSBD (1 << TIF_SSBD)
-#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
-#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
-#define _TIF_SECCOMP (1 << TIF_SECCOMP)
#define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY)
-#define _TIF_UPROBE (1 << TIF_UPROBE)
#define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING)
-#define _TIF_NOCPUID (1 << TIF_NOCPUID)
-#define _TIF_NOTSC (1 << TIF_NOTSC)
-#define _TIF_IA32 (1 << TIF_IA32)
-#define _TIF_NOHZ (1 << TIF_NOHZ)
+#define _TIF_FSCHECK (1 << TIF_FSCHECK)
+
+#define _TIF_UPROBE (1 << TIF_UPROBE)
+#define _TIF_MEMDIE (1 << TIF_MEMDIE)
#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
#define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
#define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
#define _TIF_BLOCKSTEP (1 << TIF_BLOCKSTEP)
#define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES)
-#define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT)
-#define _TIF_ADDR32 (1 << TIF_ADDR32)
-#define _TIF_X32 (1 << TIF_X32)
-#define _TIF_FSCHECK (1 << TIF_FSCHECK)
+
+#define _TIF_SECCOMP (1 << TIF_SECCOMP)
+#define _TIF_SSBD (1 << TIF_SSBD)

/*
* work to do in syscall_trace_enter(). Also includes TIF_NOHZ for
--
2.9.4