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add semtimedop call to kernel 2.4.19

PATCH In review Mark Fasheh 2 participants 3 messages Nov 4, 2002 – Nov 5, 2002

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Mark Fasheh

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#0 lore raw

PATCH 1/1 add semtimedop call to kernel 2.4.19

Hello,
Included is a patch against 2.4.19 to allow semaphore operations
with timeouts. The new call functions exactly like semtimedop in Solaris. Userspace code to use/test this new syscall can be found at:
http://www.exothermic.org/linux/semtimedop.tar.gz
Feedback is greatly appreciated :)

	--Mark

If merged, this patch can be attributed to [email protected]

arch/i386/kernel/sys_i386.c +5 -1
diff -urNp linux-2.4.19-orig/arch/i386/kernel/sys_i386.c linux-2.4.19/arch/i386/kernel/sys_i386.c
@@ -139,7 +139,11 @@ asmlinkage int sys_ipc (uint call, int f
 
 	switch (call) {
 	case SEMOP:
-		return sys_semop (first, (struct sembuf *)ptr, second);
+		return sys_semtimedop (first, (struct sembuf *)ptr, second, 
+				       NULL);
+	case SEMTIMEDOP:
+		return sys_semtimedop (first, (struct sembuf *)ptr, second,
+				       (const struct timespec *)fifth);
 	case SEMGET:
 		return sys_semget (first, second, third);
 	case SEMCTL: {
arch/ia64/ia32/sys_ia32.c +17 -1
diff -urNp linux-2.4.19-orig/arch/ia64/ia32/sys_ia32.c linux-2.4.19/arch/ia64/ia32/sys_ia32.c
@@ -2125,6 +2125,7 @@ struct ipc_kludge {
 #define SEMOP		 1
 #define SEMGET		 2
 #define SEMCTL		 3
+#define SEMTIMEDOP   4
 #define MSGSND		11
 #define MSGRCV		12
 #define MSGGET		13

@@ -2552,6 +2553,18 @@ shmctl32 (int first, int second, void *u
 	return err;
 }
 
+static long
+semtimedop32(int semid, struct sembuf *tsems, int nsems,
+			 const struct timespec32 *timeout32)
+{
+  struct timespec t;
+  if (get_user (t.tv_sec, &timeout32->tv_sec) || 
+	  get_user (t.tv_nsec, &timeout32->tv_nsec))
+	return -EFAULT;
+  
+  return sys_semtimedop(semid, tsems, nsems, &t);
+}
+
 asmlinkage long
 sys32_ipc (u32 call, int first, int second, int third, u32 ptr, u32 fifth)
 {

@@ -2563,7 +2576,10 @@ sys32_ipc (u32 call, int first, int seco
 	switch (call) {
 	      case SEMOP:
 		/* struct sembuf is the same on 32 and 64bit :)) */
-		return sys_semop(first, (struct sembuf *)AA(ptr), second);
+ 		return sys_semtimedop(first, (struct sembuf *)AA(ptr), second, NULL);
+ 	      case SEMTIMEDOP:
+ 		return semtimedop32(first, (struct sembuf *)AA(ptr), second,
+ 				    (const struct timespec32 *)AA(fifth));
 	      case SEMGET:
 		return sys_semget(first, second, third);
 	      case SEMCTL:
arch/ia64/kernel/entry.S +1 -1
diff -urNp linux-2.4.19-orig/arch/ia64/kernel/entry.S linux-2.4.19/arch/ia64/kernel/entry.S
@@ -1133,7 +1133,7 @@ sys_call_table:
 	data8 sys_getdents64
 	data8 sys_getunwind			// 1215
 	data8 sys_readahead
-	data8 ia64_ni_syscall
+	data8 sys_semtimedop
 	data8 ia64_ni_syscall
 	data8 ia64_ni_syscall
 	data8 ia64_ni_syscall			// 1220
include/asm-i386/ipc.h +1 -0
diff -urNp linux-2.4.19-orig/include/asm-i386/ipc.h linux-2.4.19/include/asm-i386/ipc.h
@@ -14,6 +14,7 @@ struct ipc_kludge {
 #define SEMOP		 1
 #define SEMGET		 2
 #define SEMCTL		 3
+#define SEMTIMEDOP	 4
 #define MSGSND		11
 #define MSGRCV		12
 #define MSGGET		13
include/asm-ia64/unistd.h +1 -0
diff -urNp linux-2.4.19-orig/include/asm-ia64/unistd.h linux-2.4.19/include/asm-ia64/unistd.h
@@ -206,6 +206,7 @@
 #define __NR_getdents64			1214
 #define __NR_getunwind			1215
 #define __NR_readahead			1216
+#define __NR_semtimedop     1217
 #define __NR_tkill			1229
 
 #if !defined(__ASSEMBLY__) && !defined(ASSEMBLER)
include/linux/sem.h +2 -0
diff -urNp linux-2.4.19-orig/include/linux/sem.h linux-2.4.19/include/linux/sem.h
@@ -124,6 +124,8 @@ struct sem_undo {
 asmlinkage long sys_semget (key_t key, int nsems, int semflg);
 asmlinkage long sys_semop (int semid, struct sembuf *sops, unsigned nsops);
 asmlinkage long sys_semctl (int semid, int semnum, int cmd, union semun arg);
+asmlinkage long sys_semtimedop (int semid, struct sembuf *sops,
+							   unsigned nsops, const struct timespec *timeout);
 
 #endif /* __KERNEL__ */
ipc/sem.c +25 -2
diff -urNp linux-2.4.19-orig/ipc/sem.c linux-2.4.19/ipc/sem.c
@@ -62,6 +62,7 @@
 #include <linux/spinlock.h>
 #include <linux/init.h>
 #include <linux/proc_fs.h>
+#include <linux/time.h>
 #include <asm/uaccess.h>
 #include "util.h"
 

@@ -839,6 +840,12 @@ static int alloc_undo(struct sem_array *
 
 asmlinkage long sys_semop (int semid, struct sembuf *tsops, unsigned nsops)
 {
+  return sys_semtimedop(semid, tsops, nsops, NULL);
+}
+
+asmlinkage long sys_semtimedop (int semid, struct sembuf *tsops,
+								unsigned nsops, const struct timespec *timeout)
+{
 	int error = -EINVAL;
 	struct sem_array *sma;
 	struct sembuf fast_sops[SEMOPM_FAST];

@@ -846,6 +853,7 @@ asmlinkage long sys_semop (int semid, st
 	struct sem_undo *un;
 	int undos = 0, decrease = 0, alter = 0;
 	struct sem_queue queue;
+	unsigned long jiffies = MAX_SCHEDULE_TIMEOUT;
 
 	if (nsops < 1 || semid < 0)
 		return -EINVAL;

@@ -860,6 +868,19 @@ asmlinkage long sys_semop (int semid, st
 		error=-EFAULT;
 		goto out_free;
 	}
+ 	if (timeout) {
+	  struct timespec _timeout;
+	  if (copy_from_user(&_timeout, timeout, sizeof(*timeout))) {
+		error = -EFAULT;
+		goto out_free;
+	  }
+	  if (_timeout.tv_sec < 0 || _timeout.tv_nsec < 0 ||
+		  _timeout.tv_nsec >= 1000000000L) {
+		error = -EINVAL;
+		goto out_free;
+	  }
+	  jiffies = timespec_to_jiffies(&_timeout);
+	}
 	sma = sem_lock(semid);
 	error=-EINVAL;
 	if(sma==NULL)

@@ -932,7 +953,7 @@ asmlinkage long sys_semop (int semid, st
 		current->state = TASK_INTERRUPTIBLE;
 		sem_unlock(semid);
 
-		schedule();
+		jiffies = schedule_timeout(jiffies);
 
 		tmp = sem_lock(semid);
 		if(tmp==NULL) {

@@ -943,7 +964,7 @@ asmlinkage long sys_semop (int semid, st
 			goto out_free;
 		}
 		/*
-		 * If queue.status == 1 we where woken up and
+		 * If queue.status == 1 we were woken up and
 		 * have to retry else we simply return.
 		 * If an interrupt occurred we have to clean up the
 		 * queue

@@ -957,6 +978,8 @@ asmlinkage long sys_semop (int semid, st
 				break;
 		} else {
 			error = queue.status;
+ 			if (error == -EINTR && jiffies == 0)
+			    error = -EAGAIN;
 			if (queue.prev) /* got Interrupt */
 				break;
 			/* Everything done by update_queue */
ipc/util.c +6 -0
diff -urNp linux-2.4.19-orig/ipc/util.c linux-2.4.19/ipc/util.c
@@ -355,6 +355,12 @@ asmlinkage long sys_semop (int semid, st
 	return -ENOSYS;
 }
 
+asmlinkage long sys_semtimedop (int semid, struct sembuf *sops, unsigned nsops,
+								const struct timespec *timeout)
+{
+  return -ENOSYS;
+}
+
 asmlinkage long sys_semctl (int semid, int semnum, int cmd, union semun arg)
 {
 	return -ENOSYS;
#1 lore raw
Quoted 6 lines · Mark Fasheh

Hello,
Included is a patch against 2.4.19 to allow semaphore operations
with timeouts. The new call functions exactly like semtimedop in Solaris. Userspace code to use/test this new syscall can be found at:
http://www.exothermic.org/linux/semtimedop.tar.gz
Feedback is greatly appreciated :)

Only two feedbacks from a first glance - its a 2.5 type change not a 2.4 one. Also call your local variable something other than "jiffies" as that is used for a global to do with time !

author
#2 lore raw

Re: [PATCH] add semtimedop call to kernel 2.5.46 (was against 2.4.19)

Alan, thank you very much for the feedback. I fixed the dumb variable naming and have ported the patch to kernel 2.5.46 (inlined below). As always, I'd love feedback, otherwise it'd be cool to see this merged :)

Quoted 11 lines · Alan Cox
Quoted 6 lines · Mark Fasheh

Hello,
Included is a patch against 2.4.19 to allow semaphore operations
with timeouts. The new call functions exactly like semtimedop in Solaris. Userspace code to use/test this new syscall can be found at:
http://www.exothermic.org/linux/semtimedop.tar.gz
Feedback is greatly appreciated :)

Only two feedbacks from a first glance - its a 2.5 type change not a 2.4 one. Also call your local variable something other than "jiffies" as that is used for a global to do with time !

arch/i386/kernel/sys_i386.c +5 -1
diff -urNp linux-2.5.46-orig/arch/i386/kernel/sys_i386.c linux-2.5.46/arch/i386/kernel/sys_i386.c
@@ -140,7 +140,11 @@ asmlinkage int sys_ipc (uint call, int f
 
 	switch (call) {
 	case SEMOP:
-		return sys_semop (first, (struct sembuf *)ptr, second);
+		return sys_semtimedop (first, (struct sembuf *)ptr, second, NULL);
+	case SEMTIMEDOP:
+		return sys_semtimedop (first, (struct sembuf *)ptr, second,
+							   (const struct timespec *)fifth);
+
 	case SEMGET:
 		return sys_semget (first, second, third);
 	case SEMCTL: {
arch/ia64/ia32/sys_ia32.c +1 -0
diff -urNp linux-2.5.46-orig/arch/ia64/ia32/sys_ia32.c linux-2.5.46/arch/ia64/ia32/sys_ia32.c
@@ -2124,6 +2124,7 @@ struct ipc_kludge {
 #define SEMOP		 1
 #define SEMGET		 2
 #define SEMCTL		 3
+#define SEMTIMEDOP	 4
 #define MSGSND		11
 #define MSGRCV		12
 #define MSGGET		13
arch/ia64/kernel/entry.S +1 -1
diff -urNp linux-2.5.46-orig/arch/ia64/kernel/entry.S linux-2.5.46/arch/ia64/kernel/entry.S
@@ -1254,7 +1254,7 @@ sys_call_table:
 	data8 sys_epoll_create
 	data8 sys_epoll_ctl
 	data8 sys_epoll_wait			// 1245
-	data8 ia64_ni_syscall
+	data8 sys_semtimedop
 	data8 ia64_ni_syscall
 	data8 ia64_ni_syscall
 	data8 ia64_ni_syscall
include/asm-i386/ipc.h +1 -0
diff -urNp linux-2.5.46-orig/include/asm-i386/ipc.h linux-2.5.46/include/asm-i386/ipc.h
@@ -14,6 +14,7 @@ struct ipc_kludge {
 #define SEMOP		 1
 #define SEMGET		 2
 #define SEMCTL		 3
+#define SEMTIMEDOP	 4
 #define MSGSND		11
 #define MSGRCV		12
 #define MSGGET		13
include/asm-ia64/unistd.h +1 -0
diff -urNp linux-2.5.46-orig/include/asm-ia64/unistd.h linux-2.5.46/include/asm-ia64/unistd.h
@@ -235,6 +235,7 @@
 #define __NR_epoll_create		1243
 #define __NR_epoll_ctl			1244
 #define __NR_epoll_wait			1245
+#define __NR_semtimedop			1246
 
 #if !defined(__ASSEMBLY__) && !defined(ASSEMBLER)
include/linux/sem.h +2 -0
diff -urNp linux-2.5.46-orig/include/linux/sem.h linux-2.5.46/include/linux/sem.h
@@ -140,6 +140,8 @@ struct sysv_sem {
 asmlinkage long sys_semget (key_t key, int nsems, int semflg);
 asmlinkage long sys_semop (int semid, struct sembuf *sops, unsigned nsops);
 asmlinkage long sys_semctl (int semid, int semnum, int cmd, union semun arg);
+asmlinkage long sys_semtimedop (int semid, struct sembuf *sops,
+								unsigned nsops, const struct timespec *timeout);
 
 #endif /* __KERNEL__ */
ipc/sem.c +24 -1
diff -urNp linux-2.5.46-orig/ipc/sem.c linux-2.5.46/ipc/sem.c
@@ -62,6 +62,7 @@
 #include <linux/spinlock.h>
 #include <linux/init.h>
 #include <linux/proc_fs.h>
+#include <linux/time.h>
 #include <linux/smp_lock.h>
 #include <linux/security.h>
 #include <asm/uaccess.h>

@@ -969,6 +970,12 @@ static int alloc_undo(struct sem_array *
 
 asmlinkage long sys_semop (int semid, struct sembuf *tsops, unsigned nsops)
 {
+    return sys_semtimedop(semid, tsops, nsops, NULL);
+}
+
+asmlinkage long sys_semtimedop (int semid, struct sembuf *tsops,
+								unsigned nsops, const struct timespec *timeout)
+{
 	int error = -EINVAL;
 	struct sem_array *sma;
 	struct sembuf fast_sops[SEMOPM_FAST];

@@ -976,6 +983,7 @@ asmlinkage long sys_semop (int semid, st
 	struct sem_undo *un;
 	int undos = 0, decrease = 0, alter = 0;
 	struct sem_queue queue;
+	unsigned long offset = MAX_SCHEDULE_TIMEOUT;
 
 
 	if (nsops < 1 || semid < 0)

@@ -991,6 +999,19 @@ asmlinkage long sys_semop (int semid, st
 		error=-EFAULT;
 		goto out_free;
 	}
+ 	if (timeout) {
+	  struct timespec _timeout;
+	  if (copy_from_user(&_timeout, timeout, sizeof(*timeout))) {
+		error = -EFAULT;
+		goto out_free;
+	  }
+	  if (_timeout.tv_sec < 0 || _timeout.tv_nsec < 0 ||
+		  _timeout.tv_nsec >= 1000000000L) {
+		error = -EINVAL;
+		goto out_free;
+	  }
+	  offset = timespec_to_jiffies(&_timeout);
+	}
 	lock_semundo();
 	sma = sem_lock(semid);
 	error=-EINVAL;

@@ -1058,7 +1079,7 @@ asmlinkage long sys_semop (int semid, st
 		sem_unlock(sma);
 		unlock_semundo();
 
-		schedule();
+		offset = schedule_timeout(offset);
 
 		lock_semundo();
 		sma = sem_lock(semid);

@@ -1084,6 +1105,8 @@ asmlinkage long sys_semop (int semid, st
 				break;
 		} else {
 			error = queue.status;
+ 			if (error == -EINTR && offset == 0)
+			    error = -EAGAIN;
 			if (queue.prev) /* got Interrupt */
 				break;
 			/* Everything done by update_queue */
ipc/util.c +7 -0
diff -urNp linux-2.5.46-orig/ipc/util.c linux-2.5.46/ipc/util.c
@@ -532,6 +532,13 @@ asmlinkage long sys_semop (int semid, st
 	return -ENOSYS;
 }
 
+asmlinkage long sys_semtimedop (int semid, struct sembuf *sops, unsigned nsops,
+								const struct timespec *timeout)
+{
+	return -ENOSYS;
+}
+
+
 asmlinkage long sys_semctl (int semid, int semnum, int cmd, union semun arg)
 {
 	return -ENOSYS;