X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=syslet.h;h=16f81d2f52ec446c447abaf0a3ad9294a3dde9a5;hp=d89abd440822f0fcf74c9cb7c3cb3c9670749a02;hb=2ba1c290d09af6d630d84a58b97b8032f73bc2ce;hpb=ad18c1ecc367c55e4d10acb05790be2c946053e2

diff --git a/syslet.h b/syslet.h
index d89abd44..16f81d2f 100644
--- a/syslet.h
+++ b/syslet.h
@@ -1,140 +1,50 @@
-#ifndef _LINUX_SYSLET_H
-#define _LINUX_SYSLET_H
-/*
- * The syslet subsystem - asynchronous syscall execution support.
- *
- * Started by Ingo Molnar:
- *
- *  Copyright (C) 2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- *
- * User-space API/ABI definitions:
- */
+#ifndef _SYSLET_H_
+#define _SYSLET_H_
 
-#ifndef __user
-# define __user
-#endif
+#include "kcompat.h"
 
-/*
- * This is the 'Syslet Atom' - the basic unit of execution
- * within the syslet framework. A syslet always represents
- * a single system-call plus its arguments, plus has conditions
- * attached to it that allows the construction of larger
- * programs from these atoms. User-space variables can be used
- * (for example a loop index) via the special sys_umem*() syscalls.
- *
- * Arguments are implemented via pointers to arguments. This not
- * only increases the flexibility of syslet atoms (multiple syslets
- * can share the same variable for example), but is also an
- * optimization: copy_uatom() will only fetch syscall parameters
- * up until the point it meets the first NULL pointer. 50% of all
- * syscalls have 2 or less parameters (and 90% of all syscalls have
- * 4 or less parameters).
- *
- * [ Note: since the argument array is at the end of the atom, and the
- *   kernel will not touch any argument beyond the final NULL one, atoms
- *   might be packed more tightly. (the only special case exception to
- *   this rule would be SKIP_TO_NEXT_ON_STOP atoms, where the kernel will
- *   jump a full syslet_uatom number of bytes.) ]
- */
-struct syslet_uatom {
-	unsigned long				flags;
-	unsigned long				nr;
-	long __user				*ret_ptr;
-	struct syslet_uatom	__user		*next;
-	unsigned long		__user		*arg_ptr[6];
-	/*
-	 * User-space can put anything in here, kernel will not
-	 * touch it:
-	 */
-	void __user				*private;
+struct syslet_frame {
+	u64 ip;
+	u64 sp;
 };
 
-/*
- * Flags to modify/control syslet atom behavior:
- */
-
-/*
- * Immediately queue this syslet asynchronously - do not even
- * attempt to execute it synchronously in the user context:
- */
-#define SYSLET_ASYNC				0x00000001
-
-/*
- * Never queue this syslet asynchronously - even if synchronous
- * execution causes a context-switching:
- */
-#define SYSLET_SYNC				0x00000002
+struct syslet_args {
+	u64 ring_ptr;
+	u64 caller_data;
+	struct syslet_frame frame;
+};
 
-/*
- * Do not queue the syslet in the completion ring when done.
- *
- * ( the default is that the final atom of a syslet is queued
- *   in the completion ring. )
- *
- * Some syscalls generate implicit completion events of their
- * own.
- */
-#define SYSLET_NO_COMPLETE			0x00000004
+struct syslet_completion {
+	u64 status;
+	u64 caller_data;
+};
 
-/*
- * Execution control: conditions upon the return code
- * of the previous syslet atom. 'Stop' means syslet
- * execution is stopped and the atom is put into the
- * completion ring:
- */
-#define SYSLET_STOP_ON_NONZERO			0x00000008
-#define SYSLET_STOP_ON_ZERO			0x00000010
-#define SYSLET_STOP_ON_NEGATIVE			0x00000020
-#define SYSLET_STOP_ON_NON_POSITIVE		0x00000040
+struct syslet_ring {
+	u32 kernel_head;
+	u32 user_tail;
+	u32 elements;
+	u32 wait_group;
+	struct syslet_completion comp[0];
+};
 
-#define SYSLET_STOP_MASK				\
-	(	SYSLET_STOP_ON_NONZERO		|	\
-		SYSLET_STOP_ON_ZERO		|	\
-		SYSLET_STOP_ON_NEGATIVE		|	\
-		SYSLET_STOP_ON_NON_POSITIVE		)
+#ifdef __x86_64__
+#define __NR_syslet_ring_wait	287
+#elif defined __i386__
+#define __NR_syslet_ring_wait	326
+#endif
 
-/*
- * Special modifier to 'stop' handling: instead of stopping the
- * execution of the syslet, the linearly next syslet is executed.
- * (Normal execution flows along atom->next, and execution stops
- *  if atom->next is NULL or a stop condition becomes true.)
- *
- * This is what allows true branches of execution within syslets.
- */
-#define SYSLET_SKIP_TO_NEXT_ON_STOP		0x00000080
+#define ESYSLETPENDING   132
 
-/*
- * This is the (per-user-context) descriptor of the async completion
- * ring. This gets registered via sys_async_register().
- */
-struct async_head_user {
-	/*
-	 * Pointers to completed async syslets (i.e. syslets that
-	 * generated a cachemiss and went async, returning -EASYNCSYSLET
-	 * to the user context by sys_async_exec()) are queued here.
-	 * Syslets that were executed synchronously are not queued here.
-	 *
-	 * Note: the final atom that generated the exit condition is
-	 * queued here. Normally this would be the last atom of a syslet.
-	 */
-	struct syslet_uatom __user		**completion_ring;
-	/*
-	 * Ring size in bytes:
-	 */
-	unsigned long				ring_size_bytes;
+typedef void (*syslet_return_func_t)(void);
 
-	/*
-	 * Maximum number of asynchronous contexts the kernel creates.
-	 *
-	 * -1UL has a special meaning: the kernel manages the optimal
-	 * size of the async pool.
-	 *
-	 * Note: this field should be valid for the lifetime of async
-	 * processing, because future kernels detect changes to this
-	 * field. (enabling user-space to control the size of the async
-	 * pool in a low-overhead fashion)
-	 */
-	unsigned long				max_nr_threads;
-};
+void fill_syslet_args(struct syslet_args *args, struct syslet_ring *ring,
+		      uint64_t caller_data, syslet_return_func_t func,
+		      void *stack)
+{
+	args->ring_ptr = (u64)(unsigned long)ring;
+	args->caller_data = caller_data;
+	args->frame.ip = (u64)(unsigned long)func;
+	args->frame.sp = (u64)(unsigned long)stack;
+}
 
 #endif