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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2015-01-15 09:46:14 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2015-01-15 09:46:14 -0800
commit0c49cd295d42d0032af11d55e2140dbec11dc8d0 (patch)
tree1e7d0e50b6b6d6e4de1fb6bb0b6d856c3932da58 /include/uapi/linux/sem.h
parent0c3e99437a66e4c869c60c2398449e6d98f3a988 (diff)
parenteaa27f34e91a14cdceed26ed6c6793ec1d186115 (diff)
Merge tag 'v3.19-rc4' into next
Merge with mainline to bring in the latest thermal and other changes.
Diffstat (limited to 'include/uapi/linux/sem.h')
-rw-r--r--include/uapi/linux/sem.h18
1 files changed, 15 insertions, 3 deletions
diff --git a/include/uapi/linux/sem.h b/include/uapi/linux/sem.h
index 541fce03b50c..dd73b908b2f3 100644
--- a/include/uapi/linux/sem.h
+++ b/include/uapi/linux/sem.h
@@ -63,10 +63,22 @@ struct seminfo {
int semaem;
};
-#define SEMMNI 128 /* <= IPCMNI max # of semaphore identifiers */
-#define SEMMSL 250 /* <= 8 000 max num of semaphores per id */
+/*
+ * SEMMNI, SEMMSL and SEMMNS are default values which can be
+ * modified by sysctl.
+ * The values has been chosen to be larger than necessary for any
+ * known configuration.
+ *
+ * SEMOPM should not be increased beyond 1000, otherwise there is the
+ * risk that semop()/semtimedop() fails due to kernel memory fragmentation when
+ * allocating the sop array.
+ */
+
+
+#define SEMMNI 32000 /* <= IPCMNI max # of semaphore identifiers */
+#define SEMMSL 32000 /* <= INT_MAX max num of semaphores per id */
#define SEMMNS (SEMMNI*SEMMSL) /* <= INT_MAX max # of semaphores in system */
-#define SEMOPM 32 /* <= 1 000 max num of ops per semop call */
+#define SEMOPM 500 /* <= 1 000 max num of ops per semop call */
#define SEMVMX 32767 /* <= 32767 semaphore maximum value */
#define SEMAEM SEMVMX /* adjust on exit max value */