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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/fs/ocfs2/cluster/masklog.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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diff --git a/kernel/fs/ocfs2/cluster/masklog.h b/kernel/fs/ocfs2/cluster/masklog.h
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+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * Copyright (C) 2005 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef O2CLUSTER_MASKLOG_H
+#define O2CLUSTER_MASKLOG_H
+
+/*
+ * For now this is a trivial wrapper around printk() that gives the critical
+ * ability to enable sets of debugging output at run-time. In the future this
+ * will almost certainly be redirected to relayfs so that it can pay a
+ * substantially lower heisenberg tax.
+ *
+ * Callers associate the message with a bitmask and a global bitmask is
+ * maintained with help from /proc. If any of the bits match the message is
+ * output.
+ *
+ * We must have efficient bit tests on i386 and it seems gcc still emits crazy
+ * code for the 64bit compare. It emits very good code for the dual unsigned
+ * long tests, though, completely avoiding tests that can never pass if the
+ * caller gives a constant bitmask that fills one of the longs with all 0s. So
+ * the desire is to have almost all of the calls decided on by comparing just
+ * one of the longs. This leads to having infrequently given bits that are
+ * frequently matched in the high bits.
+ *
+ * _ERROR and _NOTICE are used for messages that always go to the console and
+ * have appropriate KERN_ prefixes. We wrap these in our function instead of
+ * just calling printk() so that this can eventually make its way through
+ * relayfs along with the debugging messages. Everything else gets KERN_DEBUG.
+ * The inline tests and macro dance give GCC the opportunity to quite cleverly
+ * only emit the appropriage printk() when the caller passes in a constant
+ * mask, as is almost always the case.
+ *
+ * All this bitmask nonsense is managed from the files under
+ * /sys/fs/o2cb/logmask/. Reading the files gives a straightforward
+ * indication of which bits are allowed (allow) or denied (off/deny).
+ * ENTRY deny
+ * EXIT deny
+ * TCP off
+ * MSG off
+ * SOCKET off
+ * ERROR allow
+ * NOTICE allow
+ *
+ * Writing changes the state of a given bit and requires a strictly formatted
+ * single write() call:
+ *
+ * write(fd, "allow", 5);
+ *
+ * Echoing allow/deny/off string into the logmask files can flip the bits
+ * on or off as expected; here is the bash script for example:
+ *
+ * log_mask="/sys/fs/o2cb/log_mask"
+ * for node in ENTRY EXIT TCP MSG SOCKET ERROR NOTICE; do
+ * echo allow >"$log_mask"/"$node"
+ * done
+ *
+ * The debugfs.ocfs2 tool can also flip the bits with the -l option:
+ *
+ * debugfs.ocfs2 -l TCP allow
+ */
+
+/* for task_struct */
+#include <linux/sched.h>
+
+/* bits that are frequently given and infrequently matched in the low word */
+/* NOTE: If you add a flag, you need to also update masklog.c! */
+#define ML_TCP 0x0000000000000001ULL /* net cluster/tcp.c */
+#define ML_MSG 0x0000000000000002ULL /* net network messages */
+#define ML_SOCKET 0x0000000000000004ULL /* net socket lifetime */
+#define ML_HEARTBEAT 0x0000000000000008ULL /* hb all heartbeat tracking */
+#define ML_HB_BIO 0x0000000000000010ULL /* hb io tracing */
+#define ML_DLMFS 0x0000000000000020ULL /* dlm user dlmfs */
+#define ML_DLM 0x0000000000000040ULL /* dlm general debugging */
+#define ML_DLM_DOMAIN 0x0000000000000080ULL /* dlm domain debugging */
+#define ML_DLM_THREAD 0x0000000000000100ULL /* dlm domain thread */
+#define ML_DLM_MASTER 0x0000000000000200ULL /* dlm master functions */
+#define ML_DLM_RECOVERY 0x0000000000000400ULL /* dlm master functions */
+#define ML_DLM_GLUE 0x0000000000000800ULL /* ocfs2 dlm glue layer */
+#define ML_VOTE 0x0000000000001000ULL /* ocfs2 node messaging */
+#define ML_CONN 0x0000000000002000ULL /* net connection management */
+#define ML_QUORUM 0x0000000000004000ULL /* net connection quorum */
+#define ML_BASTS 0x0000000000008000ULL /* dlmglue asts and basts */
+#define ML_CLUSTER 0x0000000000010000ULL /* cluster stack */
+
+/* bits that are infrequently given and frequently matched in the high word */
+#define ML_ERROR 0x1000000000000000ULL /* sent to KERN_ERR */
+#define ML_NOTICE 0x2000000000000000ULL /* setn to KERN_NOTICE */
+#define ML_KTHREAD 0x4000000000000000ULL /* kernel thread activity */
+
+#define MLOG_INITIAL_AND_MASK (ML_ERROR|ML_NOTICE)
+#ifndef MLOG_MASK_PREFIX
+#define MLOG_MASK_PREFIX 0
+#endif
+
+/*
+ * When logging is disabled, force the bit test to 0 for anything other
+ * than errors and notices, allowing gcc to remove the code completely.
+ * When enabled, allow all masks.
+ */
+#if defined(CONFIG_OCFS2_DEBUG_MASKLOG)
+#define ML_ALLOWED_BITS ~0
+#else
+#define ML_ALLOWED_BITS (ML_ERROR|ML_NOTICE)
+#endif
+
+#define MLOG_MAX_BITS 64
+
+struct mlog_bits {
+ unsigned long words[MLOG_MAX_BITS / BITS_PER_LONG];
+};
+
+extern struct mlog_bits mlog_and_bits, mlog_not_bits;
+
+#if BITS_PER_LONG == 32
+
+#define __mlog_test_u64(mask, bits) \
+ ( (u32)(mask & 0xffffffff) & bits.words[0] || \
+ ((u64)(mask) >> 32) & bits.words[1] )
+#define __mlog_set_u64(mask, bits) do { \
+ bits.words[0] |= (u32)(mask & 0xffffffff); \
+ bits.words[1] |= (u64)(mask) >> 32; \
+} while (0)
+#define __mlog_clear_u64(mask, bits) do { \
+ bits.words[0] &= ~((u32)(mask & 0xffffffff)); \
+ bits.words[1] &= ~((u64)(mask) >> 32); \
+} while (0)
+#define MLOG_BITS_RHS(mask) { \
+ { \
+ [0] = (u32)(mask & 0xffffffff), \
+ [1] = (u64)(mask) >> 32, \
+ } \
+}
+
+#else /* 32bit long above, 64bit long below */
+
+#define __mlog_test_u64(mask, bits) ((mask) & bits.words[0])
+#define __mlog_set_u64(mask, bits) do { \
+ bits.words[0] |= (mask); \
+} while (0)
+#define __mlog_clear_u64(mask, bits) do { \
+ bits.words[0] &= ~(mask); \
+} while (0)
+#define MLOG_BITS_RHS(mask) { { (mask) } }
+
+#endif
+
+/*
+ * smp_processor_id() "helpfully" screams when called outside preemptible
+ * regions in current kernels. sles doesn't have the variants that don't
+ * scream. just do this instead of trying to guess which we're building
+ * against.. *sigh*.
+ */
+#define __mlog_cpu_guess ({ \
+ unsigned long _cpu = get_cpu(); \
+ put_cpu(); \
+ _cpu; \
+})
+
+/* In the following two macros, the whitespace after the ',' just
+ * before ##args is intentional. Otherwise, gcc 2.95 will eat the
+ * previous token if args expands to nothing.
+ */
+#define __mlog_printk(level, fmt, args...) \
+ printk(level "(%s,%u,%lu):%s:%d " fmt, current->comm, \
+ task_pid_nr(current), __mlog_cpu_guess, \
+ __PRETTY_FUNCTION__, __LINE__ , ##args)
+
+#define mlog(mask, fmt, args...) do { \
+ u64 __m = MLOG_MASK_PREFIX | (mask); \
+ if ((__m & ML_ALLOWED_BITS) && \
+ __mlog_test_u64(__m, mlog_and_bits) && \
+ !__mlog_test_u64(__m, mlog_not_bits)) { \
+ if (__m & ML_ERROR) \
+ __mlog_printk(KERN_ERR, "ERROR: "fmt , ##args); \
+ else if (__m & ML_NOTICE) \
+ __mlog_printk(KERN_NOTICE, fmt , ##args); \
+ else __mlog_printk(KERN_INFO, fmt , ##args); \
+ } \
+} while (0)
+
+#define mlog_errno(st) ({ \
+ int _st = (st); \
+ if (_st != -ERESTARTSYS && _st != -EINTR && \
+ _st != AOP_TRUNCATED_PAGE && _st != -ENOSPC && \
+ _st != -EDQUOT) \
+ mlog(ML_ERROR, "status = %lld\n", (long long)_st); \
+ _st; \
+})
+
+#define mlog_bug_on_msg(cond, fmt, args...) do { \
+ if (cond) { \
+ mlog(ML_ERROR, "bug expression: " #cond "\n"); \
+ mlog(ML_ERROR, fmt, ##args); \
+ BUG(); \
+ } \
+} while (0)
+
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
+int mlog_sys_init(struct kset *o2cb_subsys);
+void mlog_sys_shutdown(void);
+
+#endif /* O2CLUSTER_MASKLOG_H */