All of lore.kernel.org
 help / color / mirror / Atom feed
From: Mike Christie <michael.christie@oracle.com>
To: geert@linux-m68k.org, vverma@digitalocean.com, hdanton@sina.com,
	hch@infradead.org, stefanha@redhat.com, jasowang@redhat.com,
	mst@redhat.com, sgarzare@redhat.com,
	virtualization@lists.linux-foundation.org,
	christian.brauner@ubuntu.com, axboe@kernel.dk,
	linux-kernel@vger.kernel.org
Subject: [PATCH V6 02/10] fork/vm: Move common PF_IO_WORKER behavior to new flag
Date: Mon, 29 Nov 2021 13:46:59 -0600	[thread overview]
Message-ID: <20211129194707.5863-3-michael.christie@oracle.com> (raw)
In-Reply-To: <20211129194707.5863-1-michael.christie@oracle.com>

This adds a new flag, PF_USER_WORKER, that's used for behavior common to
to both PF_IO_WORKER and users like vhost which will use the new
user_worker helpers that will use the flag and are added later in this
patchset.

The common behavior PF_USER_WORKER covers is the initial frame and fpu
setup and the vm reclaim handling.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
[For m68k changes]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
 arch/alpha/kernel/process.c      | 2 +-
 arch/arc/kernel/process.c        | 2 +-
 arch/arm/kernel/process.c        | 2 +-
 arch/arm64/kernel/process.c      | 2 +-
 arch/csky/kernel/process.c       | 2 +-
 arch/h8300/kernel/process.c      | 2 +-
 arch/hexagon/kernel/process.c    | 2 +-
 arch/ia64/kernel/process.c       | 2 +-
 arch/m68k/kernel/process.c       | 2 +-
 arch/microblaze/kernel/process.c | 2 +-
 arch/mips/kernel/process.c       | 2 +-
 arch/nds32/kernel/process.c      | 2 +-
 arch/nios2/kernel/process.c      | 2 +-
 arch/openrisc/kernel/process.c   | 2 +-
 arch/parisc/kernel/process.c     | 2 +-
 arch/powerpc/kernel/process.c    | 2 +-
 arch/riscv/kernel/process.c      | 2 +-
 arch/s390/kernel/process.c       | 2 +-
 arch/sh/kernel/process_32.c      | 2 +-
 arch/sparc/kernel/process_32.c   | 2 +-
 arch/sparc/kernel/process_64.c   | 2 +-
 arch/um/kernel/process.c         | 2 +-
 arch/x86/kernel/fpu/core.c       | 4 ++--
 arch/x86/kernel/process.c        | 2 +-
 arch/xtensa/kernel/process.c     | 2 +-
 include/linux/sched.h            | 1 +
 include/linux/sched/task.h       | 3 ++-
 kernel/fork.c                    | 5 ++++-
 mm/vmscan.c                      | 4 ++--
 29 files changed, 35 insertions(+), 30 deletions(-)

diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c
index 5f8527081da9..f4759e4ee4a9 100644
--- a/arch/alpha/kernel/process.c
+++ b/arch/alpha/kernel/process.c
@@ -249,7 +249,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	childti->pcb.ksp = (unsigned long) childstack;
 	childti->pcb.flags = 1;	/* set FEN, clear everything else */
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(childstack, 0,
 			sizeof(struct switch_stack) + sizeof(struct pt_regs));
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index 8e90052f6f05..b409ecb1407f 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -191,7 +191,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	childksp[0] = 0;			/* fp */
 	childksp[1] = (unsigned long)ret_from_fork; /* blink */
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(c_regs, 0, sizeof(struct pt_regs));
 
 		c_callee->r13 = kthread_arg;
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index d47159f3791c..44603062d661 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -251,7 +251,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 	thread->cpu_domain = get_domain();
 #endif
 
-	if (likely(!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))) {
+	if (likely(!(p->flags & (PF_KTHREAD | PF_USER_WORKER)))) {
 		*childregs = *current_pt_regs();
 		childregs->ARM_r0 = 0;
 		if (stack_start)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index aacf2f5559a8..b4c6c41847be 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -333,7 +333,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 
 	ptrauth_thread_init_kernel(p);
 
-	if (likely(!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))) {
+	if (likely(!(p->flags & (PF_KTHREAD | PF_USER_WORKER)))) {
 		*childregs = *current_pt_regs();
 		childregs->regs[0] = 0;
 
diff --git a/arch/csky/kernel/process.c b/arch/csky/kernel/process.c
index 3d0ca22cd0e2..509f2bfe4ace 100644
--- a/arch/csky/kernel/process.c
+++ b/arch/csky/kernel/process.c
@@ -49,7 +49,7 @@ int copy_thread(unsigned long clone_flags,
 	/* setup thread.sp for switch_to !!! */
 	p->thread.sp = (unsigned long)childstack;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childstack->r15 = (unsigned long) ret_from_kernel_thread;
 		childstack->r10 = kthread_arg;
diff --git a/arch/h8300/kernel/process.c b/arch/h8300/kernel/process.c
index 8833fa4f5d51..050aca44ba6d 100644
--- a/arch/h8300/kernel/process.c
+++ b/arch/h8300/kernel/process.c
@@ -112,7 +112,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 
 	childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->retpc = (unsigned long) ret_from_kernel_thread;
 		childregs->er4 = topstk; /* arg */
diff --git a/arch/hexagon/kernel/process.c b/arch/hexagon/kernel/process.c
index 232dfd8956aa..40f8294c6c7c 100644
--- a/arch/hexagon/kernel/process.c
+++ b/arch/hexagon/kernel/process.c
@@ -73,7 +73,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 						    sizeof(*ss));
 	ss->lr = (unsigned long)ret_from_fork;
 	p->thread.switch_sp = ss;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		/* r24 <- fn, r25 <- arg */
 		ss->r24 = usp;
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 834df24a88f1..29015ebdcf1d 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -338,7 +338,7 @@ copy_thread(unsigned long clone_flags, unsigned long user_stack_base,
 
 	ia64_drop_fpu(p);	/* don't pick up stale state from a CPU's fph */
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		if (unlikely(!user_stack_base)) {
 			/* fork_idle() called us */
 			return 0;
diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c
index a6030dbaa089..cbb693012b5e 100644
--- a/arch/m68k/kernel/process.c
+++ b/arch/m68k/kernel/process.c
@@ -157,7 +157,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	 */
 	p->thread.fc = USER_DATA;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(frame, 0, sizeof(struct fork_frame));
 		frame->regs.sr = PS_S;
diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c
index 5e2b91c1e8ce..de1da9900f7e 100644
--- a/arch/microblaze/kernel/process.c
+++ b/arch/microblaze/kernel/process.c
@@ -59,7 +59,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct pt_regs *childregs = task_pt_regs(p);
 	struct thread_info *ti = task_thread_info(p);
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* if we're creating a new kernel thread then just zeroing all
 		 * the registers. That's OK for a brand new thread.*/
 		memset(childregs, 0, sizeof(struct pt_regs));
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index cbff1b974f88..6f1ed337cd41 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -120,7 +120,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	/*  Put the stack after the struct pt_regs.  */
 	childksp = (unsigned long) childregs;
 	p->thread.cp0_status = (read_c0_status() & ~(ST0_CU2|ST0_CU1)) | ST0_KERNEL_CUMASK;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		unsigned long status = p->thread.cp0_status;
 		memset(childregs, 0, sizeof(struct pt_regs));
diff --git a/arch/nds32/kernel/process.c b/arch/nds32/kernel/process.c
index 49fab9e39cbf..dba91dd1e289 100644
--- a/arch/nds32/kernel/process.c
+++ b/arch/nds32/kernel/process.c
@@ -156,7 +156,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 
 	memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context));
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		/* kernel thread fn */
 		p->thread.cpu_context.r6 = stack_start;
diff --git a/arch/nios2/kernel/process.c b/arch/nios2/kernel/process.c
index f8ea522a1588..eabf3452e5e2 100644
--- a/arch/nios2/kernel/process.c
+++ b/arch/nios2/kernel/process.c
@@ -109,7 +109,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct switch_stack *childstack =
 		((struct switch_stack *)childregs) - 1;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childstack, 0,
 			sizeof(struct switch_stack) + sizeof(struct pt_regs));
 
diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c
index 3c0c91bcdcba..aa110383cfa1 100644
--- a/arch/openrisc/kernel/process.c
+++ b/arch/openrisc/kernel/process.c
@@ -172,7 +172,7 @@ copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	sp -= sizeof(struct pt_regs);
 	kregs = (struct pt_regs *)sp;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(kregs, 0, sizeof(struct pt_regs));
 		kregs->gpr[20] = usp; /* fn, kernel thread */
 		kregs->gpr[22] = arg;
diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c
index ea3d83b6fb62..a76120e30eb4 100644
--- a/arch/parisc/kernel/process.c
+++ b/arch/parisc/kernel/process.c
@@ -197,7 +197,7 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
 	extern void * const ret_from_kernel_thread;
 	extern void * const child_return;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(cregs, 0, sizeof(struct pt_regs));
 		if (!usp) /* idle thread */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 406d7ee9e322..0b06b7809816 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1700,7 +1700,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	/* Copy registers */
 	sp -= sizeof(struct pt_regs);
 	childregs = (struct pt_regs *) sp;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->gpr[1] = sp + sizeof(struct pt_regs);
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 03ac3aa611f5..8deeb94eb51e 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -125,7 +125,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct pt_regs *childregs = task_pt_regs(p);
 
 	/* p->thread holds context to be restored by __switch_to() */
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* Kernel thread */
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->gp = gp_in_global;
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index e8858b2de24b..5ce90a23b1eb 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -130,7 +130,7 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
 	frame->sf.gprs[9] = (unsigned long)frame;
 
 	/* Store access registers to kernel stack of new process. */
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(&frame->childregs, 0, sizeof(struct pt_regs));
 		frame->childregs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_DAT |
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
index 1c28e3cddb60..0506a739b0a8 100644
--- a/arch/sh/kernel/process_32.c
+++ b/arch/sh/kernel/process_32.c
@@ -114,7 +114,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 
 	childregs = task_pt_regs(p);
 	p->thread.sp = (unsigned long) childregs;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		p->thread.pc = (unsigned long) ret_from_kernel_thread;
 		childregs->regs[4] = arg;
diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c
index 2dc0bf9fe62e..5386e56b5e6c 100644
--- a/arch/sparc/kernel/process_32.c
+++ b/arch/sparc/kernel/process_32.c
@@ -296,7 +296,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 	ti->ksp = (unsigned long) new_stack;
 	p->thread.kregs = childregs;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		extern int nwindows;
 		unsigned long psr;
 		memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index f5b2cac8669f..6058b3966f71 100644
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -594,7 +594,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 				       sizeof(struct sparc_stackf));
 	t->fpsaved[0] = 0;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(child_trap_frame, 0, child_stack_sz);
 		__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
 			(current_pt_regs()->tstate + 1) & TSTATE_CWP;
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 82107373ac7e..2cb57aefacbe 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -157,7 +157,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 		unsigned long arg, struct task_struct * p, unsigned long tls)
 {
 	void (*handler)(void);
-	int kthread = current->flags & (PF_KTHREAD | PF_IO_WORKER);
+	int kthread = current->flags & (PF_KTHREAD | PF_USER_WORKER);
 	int ret = 0;
 
 	p->thread = (struct thread_struct) INIT_THREAD;
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 8ea306b1bf8e..f3fc1b1db999 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -485,10 +485,10 @@ int fpu_clone(struct task_struct *dst, unsigned long clone_flags)
 	set_tsk_thread_flag(dst, TIF_NEED_FPU_LOAD);
 
 	/*
-	 * No FPU state inheritance for kernel threads and IO
+	 * No FPU state inheritance for kernel threads and user
 	 * worker threads.
 	 */
-	if (dst->flags & (PF_KTHREAD | PF_IO_WORKER)) {
+	if (dst->flags & (PF_KTHREAD | PF_USER_WORKER)) {
 		/* Clear out the minimal state */
 		memcpy(&dst_fpu->fpstate->regs, &init_fpstate.regs,
 		       init_fpstate_copy_size());
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 04143a653a8a..7c451f234c26 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -195,7 +195,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 	task_user_gs(p) = get_user_gs(current_pt_regs());
 #endif
 
-	if (unlikely(p->flags & PF_IO_WORKER)) {
+	if (unlikely(p->flags & PF_USER_WORKER)) {
 		/*
 		 * An IO thread is a user space thread, but it doesn't
 		 * return to ret_after_fork().
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index bd80df890b1e..00d81668ead4 100644
--- a/arch/xtensa/kernel/process.c
+++ b/arch/xtensa/kernel/process.c
@@ -224,7 +224,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
 #error Unsupported Xtensa ABI
 #endif
 
-	if (!(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (!(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		struct pt_regs *regs = current_pt_regs();
 		unsigned long usp = usp_thread_fn ?
 			usp_thread_fn : regs->areg[1];
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 78c351e35fec..5ca45456a77a 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1683,6 +1683,7 @@ extern struct pid *cad_pid;
 #define PF_KTHREAD		0x00200000	/* I am a kernel thread */
 #define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
 #define PF_SWAPWRITE		0x00800000	/* Allowed to write to swap */
+#define PF_USER_WORKER		0x01000000	/* Kernel thread cloned from userspace thread */
 #define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
 #define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
 #define PF_MEMALLOC_PIN		0x10000000	/* Allocation context constrained to zones which allow long term pinning. */
diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index 65d5ec3a8a04..b7861cb6a74b 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -18,7 +18,8 @@ struct css_set;
 /* All the bits taken by the old clone syscall. */
 #define CLONE_LEGACY_FLAGS 0xffffffffULL
 
-#define USER_WORKER_IO		BIT(0)
+#define USER_WORKER		BIT(0)
+#define USER_WORKER_IO		BIT(1)
 
 struct kernel_clone_args {
 	u64 flags;
diff --git a/kernel/fork.c b/kernel/fork.c
index 6effd839d566..0d278ac26f2f 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2032,6 +2032,9 @@ static __latent_entropy struct task_struct *copy_process(
 		siginitsetinv(&p->blocked, sigmask(SIGKILL)|sigmask(SIGSTOP));
 	}
 
+	if (args->worker_flags & USER_WORKER)
+		p->flags |= PF_USER_WORKER;
+
 	/*
 	 * This _must_ happen before we call free_task(), i.e. before we jump
 	 * to any of the bad_fork_* labels. This is to avoid freeing
@@ -2524,7 +2527,7 @@ struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node)
 		.exit_signal	= (lower_32_bits(flags) & CSIGNAL),
 		.stack		= (unsigned long)fn,
 		.stack_size	= (unsigned long)arg,
-		.worker_flags	= USER_WORKER_IO,
+		.worker_flags	= USER_WORKER | USER_WORKER_IO,
 	};
 
 	return copy_process(NULL, 0, node, &args);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index fb9584641ac7..f504ff88a09d 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1028,12 +1028,12 @@ void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason)
 	DEFINE_WAIT(wait);
 
 	/*
-	 * Do not throttle IO workers, kthreads other than kswapd or
+	 * Do not throttle user workers, kthreads other than kswapd or
 	 * workqueues. They may be required for reclaim to make
 	 * forward progress (e.g. journalling workqueues or kthreads).
 	 */
 	if (!current_is_kswapd() &&
-	    current->flags & (PF_IO_WORKER|PF_KTHREAD))
+	    current->flags & (PF_USER_WORKER|PF_KTHREAD))
 		return;
 
 	/*
-- 
2.25.1

_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

WARNING: multiple messages have this Message-ID (diff)
From: Mike Christie <michael.christie@oracle.com>
To: geert@linux-m68k.org, vverma@digitalocean.com, hdanton@sina.com,
	hch@infradead.org, stefanha@redhat.com, jasowang@redhat.com,
	mst@redhat.com, sgarzare@redhat.com,
	virtualization@lists.linux-foundation.org,
	christian.brauner@ubuntu.com, axboe@kernel.dk,
	linux-kernel@vger.kernel.org
Cc: Mike Christie <michael.christie@oracle.com>
Subject: [PATCH V6 02/10] fork/vm: Move common PF_IO_WORKER behavior to new flag
Date: Mon, 29 Nov 2021 13:46:59 -0600	[thread overview]
Message-ID: <20211129194707.5863-3-michael.christie@oracle.com> (raw)
In-Reply-To: <20211129194707.5863-1-michael.christie@oracle.com>

This adds a new flag, PF_USER_WORKER, that's used for behavior common to
to both PF_IO_WORKER and users like vhost which will use the new
user_worker helpers that will use the flag and are added later in this
patchset.

The common behavior PF_USER_WORKER covers is the initial frame and fpu
setup and the vm reclaim handling.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
[For m68k changes]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
 arch/alpha/kernel/process.c      | 2 +-
 arch/arc/kernel/process.c        | 2 +-
 arch/arm/kernel/process.c        | 2 +-
 arch/arm64/kernel/process.c      | 2 +-
 arch/csky/kernel/process.c       | 2 +-
 arch/h8300/kernel/process.c      | 2 +-
 arch/hexagon/kernel/process.c    | 2 +-
 arch/ia64/kernel/process.c       | 2 +-
 arch/m68k/kernel/process.c       | 2 +-
 arch/microblaze/kernel/process.c | 2 +-
 arch/mips/kernel/process.c       | 2 +-
 arch/nds32/kernel/process.c      | 2 +-
 arch/nios2/kernel/process.c      | 2 +-
 arch/openrisc/kernel/process.c   | 2 +-
 arch/parisc/kernel/process.c     | 2 +-
 arch/powerpc/kernel/process.c    | 2 +-
 arch/riscv/kernel/process.c      | 2 +-
 arch/s390/kernel/process.c       | 2 +-
 arch/sh/kernel/process_32.c      | 2 +-
 arch/sparc/kernel/process_32.c   | 2 +-
 arch/sparc/kernel/process_64.c   | 2 +-
 arch/um/kernel/process.c         | 2 +-
 arch/x86/kernel/fpu/core.c       | 4 ++--
 arch/x86/kernel/process.c        | 2 +-
 arch/xtensa/kernel/process.c     | 2 +-
 include/linux/sched.h            | 1 +
 include/linux/sched/task.h       | 3 ++-
 kernel/fork.c                    | 5 ++++-
 mm/vmscan.c                      | 4 ++--
 29 files changed, 35 insertions(+), 30 deletions(-)

diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c
index 5f8527081da9..f4759e4ee4a9 100644
--- a/arch/alpha/kernel/process.c
+++ b/arch/alpha/kernel/process.c
@@ -249,7 +249,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	childti->pcb.ksp = (unsigned long) childstack;
 	childti->pcb.flags = 1;	/* set FEN, clear everything else */
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(childstack, 0,
 			sizeof(struct switch_stack) + sizeof(struct pt_regs));
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index 8e90052f6f05..b409ecb1407f 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -191,7 +191,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	childksp[0] = 0;			/* fp */
 	childksp[1] = (unsigned long)ret_from_fork; /* blink */
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(c_regs, 0, sizeof(struct pt_regs));
 
 		c_callee->r13 = kthread_arg;
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index d47159f3791c..44603062d661 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -251,7 +251,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 	thread->cpu_domain = get_domain();
 #endif
 
-	if (likely(!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))) {
+	if (likely(!(p->flags & (PF_KTHREAD | PF_USER_WORKER)))) {
 		*childregs = *current_pt_regs();
 		childregs->ARM_r0 = 0;
 		if (stack_start)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index aacf2f5559a8..b4c6c41847be 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -333,7 +333,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 
 	ptrauth_thread_init_kernel(p);
 
-	if (likely(!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))) {
+	if (likely(!(p->flags & (PF_KTHREAD | PF_USER_WORKER)))) {
 		*childregs = *current_pt_regs();
 		childregs->regs[0] = 0;
 
diff --git a/arch/csky/kernel/process.c b/arch/csky/kernel/process.c
index 3d0ca22cd0e2..509f2bfe4ace 100644
--- a/arch/csky/kernel/process.c
+++ b/arch/csky/kernel/process.c
@@ -49,7 +49,7 @@ int copy_thread(unsigned long clone_flags,
 	/* setup thread.sp for switch_to !!! */
 	p->thread.sp = (unsigned long)childstack;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childstack->r15 = (unsigned long) ret_from_kernel_thread;
 		childstack->r10 = kthread_arg;
diff --git a/arch/h8300/kernel/process.c b/arch/h8300/kernel/process.c
index 8833fa4f5d51..050aca44ba6d 100644
--- a/arch/h8300/kernel/process.c
+++ b/arch/h8300/kernel/process.c
@@ -112,7 +112,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 
 	childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->retpc = (unsigned long) ret_from_kernel_thread;
 		childregs->er4 = topstk; /* arg */
diff --git a/arch/hexagon/kernel/process.c b/arch/hexagon/kernel/process.c
index 232dfd8956aa..40f8294c6c7c 100644
--- a/arch/hexagon/kernel/process.c
+++ b/arch/hexagon/kernel/process.c
@@ -73,7 +73,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 						    sizeof(*ss));
 	ss->lr = (unsigned long)ret_from_fork;
 	p->thread.switch_sp = ss;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		/* r24 <- fn, r25 <- arg */
 		ss->r24 = usp;
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 834df24a88f1..29015ebdcf1d 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -338,7 +338,7 @@ copy_thread(unsigned long clone_flags, unsigned long user_stack_base,
 
 	ia64_drop_fpu(p);	/* don't pick up stale state from a CPU's fph */
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		if (unlikely(!user_stack_base)) {
 			/* fork_idle() called us */
 			return 0;
diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c
index a6030dbaa089..cbb693012b5e 100644
--- a/arch/m68k/kernel/process.c
+++ b/arch/m68k/kernel/process.c
@@ -157,7 +157,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	 */
 	p->thread.fc = USER_DATA;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(frame, 0, sizeof(struct fork_frame));
 		frame->regs.sr = PS_S;
diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c
index 5e2b91c1e8ce..de1da9900f7e 100644
--- a/arch/microblaze/kernel/process.c
+++ b/arch/microblaze/kernel/process.c
@@ -59,7 +59,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct pt_regs *childregs = task_pt_regs(p);
 	struct thread_info *ti = task_thread_info(p);
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* if we're creating a new kernel thread then just zeroing all
 		 * the registers. That's OK for a brand new thread.*/
 		memset(childregs, 0, sizeof(struct pt_regs));
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index cbff1b974f88..6f1ed337cd41 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -120,7 +120,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	/*  Put the stack after the struct pt_regs.  */
 	childksp = (unsigned long) childregs;
 	p->thread.cp0_status = (read_c0_status() & ~(ST0_CU2|ST0_CU1)) | ST0_KERNEL_CUMASK;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		unsigned long status = p->thread.cp0_status;
 		memset(childregs, 0, sizeof(struct pt_regs));
diff --git a/arch/nds32/kernel/process.c b/arch/nds32/kernel/process.c
index 49fab9e39cbf..dba91dd1e289 100644
--- a/arch/nds32/kernel/process.c
+++ b/arch/nds32/kernel/process.c
@@ -156,7 +156,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 
 	memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context));
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		/* kernel thread fn */
 		p->thread.cpu_context.r6 = stack_start;
diff --git a/arch/nios2/kernel/process.c b/arch/nios2/kernel/process.c
index f8ea522a1588..eabf3452e5e2 100644
--- a/arch/nios2/kernel/process.c
+++ b/arch/nios2/kernel/process.c
@@ -109,7 +109,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct switch_stack *childstack =
 		((struct switch_stack *)childregs) - 1;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childstack, 0,
 			sizeof(struct switch_stack) + sizeof(struct pt_regs));
 
diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c
index 3c0c91bcdcba..aa110383cfa1 100644
--- a/arch/openrisc/kernel/process.c
+++ b/arch/openrisc/kernel/process.c
@@ -172,7 +172,7 @@ copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	sp -= sizeof(struct pt_regs);
 	kregs = (struct pt_regs *)sp;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(kregs, 0, sizeof(struct pt_regs));
 		kregs->gpr[20] = usp; /* fn, kernel thread */
 		kregs->gpr[22] = arg;
diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c
index ea3d83b6fb62..a76120e30eb4 100644
--- a/arch/parisc/kernel/process.c
+++ b/arch/parisc/kernel/process.c
@@ -197,7 +197,7 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
 	extern void * const ret_from_kernel_thread;
 	extern void * const child_return;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(cregs, 0, sizeof(struct pt_regs));
 		if (!usp) /* idle thread */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 406d7ee9e322..0b06b7809816 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1700,7 +1700,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	/* Copy registers */
 	sp -= sizeof(struct pt_regs);
 	childregs = (struct pt_regs *) sp;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->gpr[1] = sp + sizeof(struct pt_regs);
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 03ac3aa611f5..8deeb94eb51e 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -125,7 +125,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct pt_regs *childregs = task_pt_regs(p);
 
 	/* p->thread holds context to be restored by __switch_to() */
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* Kernel thread */
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->gp = gp_in_global;
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index e8858b2de24b..5ce90a23b1eb 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -130,7 +130,7 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
 	frame->sf.gprs[9] = (unsigned long)frame;
 
 	/* Store access registers to kernel stack of new process. */
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		/* kernel thread */
 		memset(&frame->childregs, 0, sizeof(struct pt_regs));
 		frame->childregs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_DAT |
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
index 1c28e3cddb60..0506a739b0a8 100644
--- a/arch/sh/kernel/process_32.c
+++ b/arch/sh/kernel/process_32.c
@@ -114,7 +114,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 
 	childregs = task_pt_regs(p);
 	p->thread.sp = (unsigned long) childregs;
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		p->thread.pc = (unsigned long) ret_from_kernel_thread;
 		childregs->regs[4] = arg;
diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c
index 2dc0bf9fe62e..5386e56b5e6c 100644
--- a/arch/sparc/kernel/process_32.c
+++ b/arch/sparc/kernel/process_32.c
@@ -296,7 +296,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 	ti->ksp = (unsigned long) new_stack;
 	p->thread.kregs = childregs;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		extern int nwindows;
 		unsigned long psr;
 		memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index f5b2cac8669f..6058b3966f71 100644
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -594,7 +594,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 				       sizeof(struct sparc_stackf));
 	t->fpsaved[0] = 0;
 
-	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		memset(child_trap_frame, 0, child_stack_sz);
 		__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
 			(current_pt_regs()->tstate + 1) & TSTATE_CWP;
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 82107373ac7e..2cb57aefacbe 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -157,7 +157,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 		unsigned long arg, struct task_struct * p, unsigned long tls)
 {
 	void (*handler)(void);
-	int kthread = current->flags & (PF_KTHREAD | PF_IO_WORKER);
+	int kthread = current->flags & (PF_KTHREAD | PF_USER_WORKER);
 	int ret = 0;
 
 	p->thread = (struct thread_struct) INIT_THREAD;
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 8ea306b1bf8e..f3fc1b1db999 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -485,10 +485,10 @@ int fpu_clone(struct task_struct *dst, unsigned long clone_flags)
 	set_tsk_thread_flag(dst, TIF_NEED_FPU_LOAD);
 
 	/*
-	 * No FPU state inheritance for kernel threads and IO
+	 * No FPU state inheritance for kernel threads and user
 	 * worker threads.
 	 */
-	if (dst->flags & (PF_KTHREAD | PF_IO_WORKER)) {
+	if (dst->flags & (PF_KTHREAD | PF_USER_WORKER)) {
 		/* Clear out the minimal state */
 		memcpy(&dst_fpu->fpstate->regs, &init_fpstate.regs,
 		       init_fpstate_copy_size());
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 04143a653a8a..7c451f234c26 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -195,7 +195,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 	task_user_gs(p) = get_user_gs(current_pt_regs());
 #endif
 
-	if (unlikely(p->flags & PF_IO_WORKER)) {
+	if (unlikely(p->flags & PF_USER_WORKER)) {
 		/*
 		 * An IO thread is a user space thread, but it doesn't
 		 * return to ret_after_fork().
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index bd80df890b1e..00d81668ead4 100644
--- a/arch/xtensa/kernel/process.c
+++ b/arch/xtensa/kernel/process.c
@@ -224,7 +224,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
 #error Unsupported Xtensa ABI
 #endif
 
-	if (!(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+	if (!(p->flags & (PF_KTHREAD | PF_USER_WORKER))) {
 		struct pt_regs *regs = current_pt_regs();
 		unsigned long usp = usp_thread_fn ?
 			usp_thread_fn : regs->areg[1];
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 78c351e35fec..5ca45456a77a 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1683,6 +1683,7 @@ extern struct pid *cad_pid;
 #define PF_KTHREAD		0x00200000	/* I am a kernel thread */
 #define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
 #define PF_SWAPWRITE		0x00800000	/* Allowed to write to swap */
+#define PF_USER_WORKER		0x01000000	/* Kernel thread cloned from userspace thread */
 #define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
 #define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
 #define PF_MEMALLOC_PIN		0x10000000	/* Allocation context constrained to zones which allow long term pinning. */
diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index 65d5ec3a8a04..b7861cb6a74b 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -18,7 +18,8 @@ struct css_set;
 /* All the bits taken by the old clone syscall. */
 #define CLONE_LEGACY_FLAGS 0xffffffffULL
 
-#define USER_WORKER_IO		BIT(0)
+#define USER_WORKER		BIT(0)
+#define USER_WORKER_IO		BIT(1)
 
 struct kernel_clone_args {
 	u64 flags;
diff --git a/kernel/fork.c b/kernel/fork.c
index 6effd839d566..0d278ac26f2f 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2032,6 +2032,9 @@ static __latent_entropy struct task_struct *copy_process(
 		siginitsetinv(&p->blocked, sigmask(SIGKILL)|sigmask(SIGSTOP));
 	}
 
+	if (args->worker_flags & USER_WORKER)
+		p->flags |= PF_USER_WORKER;
+
 	/*
 	 * This _must_ happen before we call free_task(), i.e. before we jump
 	 * to any of the bad_fork_* labels. This is to avoid freeing
@@ -2524,7 +2527,7 @@ struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node)
 		.exit_signal	= (lower_32_bits(flags) & CSIGNAL),
 		.stack		= (unsigned long)fn,
 		.stack_size	= (unsigned long)arg,
-		.worker_flags	= USER_WORKER_IO,
+		.worker_flags	= USER_WORKER | USER_WORKER_IO,
 	};
 
 	return copy_process(NULL, 0, node, &args);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index fb9584641ac7..f504ff88a09d 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1028,12 +1028,12 @@ void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason)
 	DEFINE_WAIT(wait);
 
 	/*
-	 * Do not throttle IO workers, kthreads other than kswapd or
+	 * Do not throttle user workers, kthreads other than kswapd or
 	 * workqueues. They may be required for reclaim to make
 	 * forward progress (e.g. journalling workqueues or kthreads).
 	 */
 	if (!current_is_kswapd() &&
-	    current->flags & (PF_IO_WORKER|PF_KTHREAD))
+	    current->flags & (PF_USER_WORKER|PF_KTHREAD))
 		return;
 
 	/*
-- 
2.25.1


  parent reply	other threads:[~2021-11-29 19:47 UTC|newest]

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-29 19:46 [PATCH V6 01/10] Use copy_process in vhost layer Mike Christie
2021-11-29 19:46 ` Mike Christie
2021-11-29 19:46 ` [PATCH V6 01/10] fork: Make IO worker options flag based Mike Christie
2021-11-29 19:46   ` Mike Christie
2021-11-29 19:46 ` Mike Christie [this message]
2021-11-29 19:46   ` [PATCH V6 02/10] fork/vm: Move common PF_IO_WORKER behavior to new flag Mike Christie
2021-11-29 19:47 ` [PATCH V6 03/10] fork: add USER_WORKER flag to not dup/clone files Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-11-29 19:47 ` [PATCH V6 04/10] fork: Add USER_WORKER flag to ignore signals Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-11-29 19:47 ` [PATCH V6 05/10] signal: Perfom autoreap for PF_USER_WORKER Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-12-17 18:42   ` Eric W. Biederman
2021-12-17 18:42     ` Eric W. Biederman
2021-11-29 19:47 ` [PATCH V6 06/10] fork: add helpers to clone a process for kernel use Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-12-17 18:53   ` Eric W. Biederman
2021-12-17 18:53     ` Eric W. Biederman
2021-11-29 19:47 ` [PATCH V6 07/10] io_uring: switch to user_worker Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-11-29 19:47 ` [PATCH V6 08/10] fork: remove create_io_thread Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-11-29 19:47 ` [PATCH V6 09/10] vhost: move worker thread fields to new struct Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-11-29 19:47 ` [PATCH V6 10/10] vhost: use user_worker to check RLIMITs Mike Christie
2021-11-29 19:47   ` Mike Christie
2021-12-17 19:01   ` Eric W. Biederman
2021-12-17 19:01     ` Eric W. Biederman
2021-12-08 20:34 ` [PATCH V6 01/10] Use copy_process in vhost layer Michael S. Tsirkin
2021-12-08 20:34   ` Michael S. Tsirkin
2021-12-08 22:13   ` michael.christie
2021-12-08 22:13     ` michael.christie
2021-12-09  9:32     ` Christian Brauner
2021-12-17 19:26 ` Eric W. Biederman
2021-12-17 19:26   ` Eric W. Biederman
2021-12-17 22:08   ` michael.christie
2021-12-17 22:08     ` michael.christie
2021-12-22  0:20     ` Eric W. Biederman
2021-12-22  0:20       ` Eric W. Biederman
2021-12-22 17:32       ` Mike Christie
2021-12-22 17:32         ` Mike Christie
2021-12-22 18:24         ` Eric W. Biederman
2021-12-22 18:24           ` Eric W. Biederman
2021-12-22 20:25           ` Michael S. Tsirkin
2021-12-22 20:25             ` Michael S. Tsirkin
2022-01-17 16:41           ` Mike Christie
2022-01-17 16:41             ` Mike Christie
2022-01-17 17:31             ` Eric W. Biederman
2022-01-17 17:31               ` Eric W. Biederman
2022-01-18 18:51               ` Mike Christie
2022-01-18 18:51                 ` Mike Christie
2022-01-18 19:00                 ` Mike Christie
2022-01-18 19:00                   ` Mike Christie
2022-01-18 19:12                 ` Eric W. Biederman
2022-01-18 19:12                   ` Eric W. Biederman
2022-02-02 21:02                   ` Mike Christie
2022-02-02 21:02                     ` Mike Christie

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211129194707.5863-3-michael.christie@oracle.com \
    --to=michael.christie@oracle.com \
    --cc=axboe@kernel.dk \
    --cc=christian.brauner@ubuntu.com \
    --cc=geert@linux-m68k.org \
    --cc=hch@infradead.org \
    --cc=hdanton@sina.com \
    --cc=jasowang@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mst@redhat.com \
    --cc=sgarzare@redhat.com \
    --cc=stefanha@redhat.com \
    --cc=virtualization@lists.linux-foundation.org \
    --cc=vverma@digitalocean.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.