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* crc32: select an algorithm via KconfigDarrick J. Wong2012-03-232-0/+61
| | | | | | | | | Allow the kernel builder to choose a crc32* algorithm for the kernel. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: add self-test code for crc32cDarrick J. Wong2012-03-231-102/+261
| | | | | | | | | Add self-test code for crc32c. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: bolt on crc32cDarrick J. Wong2012-03-234-34/+95
| | | | | | | | | | | Reuse the existing crc32 code to stamp out a crc32c implementation. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Bob Pearson <rpearson@systemfabricworks.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: add note about this patchset to crc32.cBob Pearson2012-03-231-0/+4
| | | | | | | | | | Add a comment at the top of crc32.c [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: optimize loop counter for x86Bob Pearson2012-03-231-0/+13
| | | | | | | | | | | | | | | | | | | | | | | Add two changes that improve the performance of x86 systems 1. replace main loop with incrementing counter this change improves the performance of the selftest by about 5-6% on Nehalem CPUs. The apparent reason is that the compiler can use the loop index to perform an indexed memory access. This is reported to make the performance of PowerPC CPUs to get worse. 2. replace the rem_len loop with incrementing counter this change improves the performance of the selftest, which has more than the usual number of occurances, by about 1-2% on x86 CPUs. In actual work loads the length is most often a multiple of 4 bytes and this code does not get executed as often if at all. Again this change is reported to make the performance of PowerPC get worse. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: add slice-by-8 algorithm to existing codeBob Pearson2012-03-233-35/+75
| | | | | | | | | | | | | | | Add slicing-by-8 algorithm to the existing slicing-by-4 algorithm. This consists of: - extend largest BITS size from 32 to 64 - extend tables from tab[4][256] to up to tab[8][256] - Add code for inner loop. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: make CRC_*_BITS definition correspond to actual bit countsBob Pearson2012-03-233-12/+34
| | | | | | | | | | | | | | | | | | | | | | | | | crc32.c provides a choice of one of several algorithms for computing the LSB and LSB versions of the CRC32 checksum based on the parameters CRC_LE_BITS and CRC_BE_BITS. In the original version the values 1, 2, 4 and 8 respectively selected versions of the alrogithm that computed the crc 1, 2, 4 and 32 bits as a time. This patch series adds a new version that computes the CRC 64 bits at a time. To make things easier to understand the parameter has been reinterpreted to actually stand for the number of bits processed in each step of the algorithm so that the old value 8 has been replaced with the value 32. This also allows us to add in a widely used crc algorithm that computes the crc 8 bits at a time called the Sarwate algorithm. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: fix mixing of endian-specific typesBob Pearson2012-03-231-6/+6
| | | | | | | | | | | | crc32.c in its original version freely mixed u32, __le32 and __be32 types which caused warnings from sparse with __CHECK_ENDIAN__. This patch fixes these by forcing the types to u32. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: miscellaneous cleanupsBob Pearson2012-03-232-71/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | Misc cleanup of lib/crc32.c and related files. - remove unnecessary header files. - straighten out some convoluted ifdef's - rewrite some references to 2 dimensional arrays as 1 dimensional arrays to make them correct. I.e. replace tab[i] with tab[0][i]. - a few trivial whitespace changes - fix a warning in gen_crc32tables.c caused by a mismatch in the type of the pointer passed to output table. Since the table is only used at kernel compile time, it is simpler to make the table big enough to hold the largest column size used. One cannot make the column size smaller in output_table because it has to be used by both the le and be tables and they can have different column sizes. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: simplify unit test codeBob Pearson2012-03-232-117/+691
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the unit test provided in crc32.c, which doesn't have a makefile and doesn't compile with current headers, with a simpler self test routine that also gives a measure of performance and runs at module init time. The self test option can be enabled through a configuration option CONFIG_CRC32_SELFTEST. The test stresses the pre and post loops and is thus not very realistic since actual uses will likely have addresses and lengths that are at least 4 byte aligned. However, the main loop is long enough so that the performance is dominated by that loop. The expected values for crc32_le and crc32_be were generated with the original version of crc32.c using CRC_BITS_LE = 8 and CRC_BITS_BE = 8. These values were then used to check all the values of the BITS parameters in both the original and new versions. The performance results show some variability from run to run in spite of attempts to both warm the cache and reduce the amount of OS noise by limiting interrutps during the test. To get comparable results and to analyse options wrt performance the best time reported over a small sample of runs has been taken. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: move long comment about crc32 fundamentals to Documentation/Bob Pearson2012-03-231-127/+2
| | | | | | | | | | | | | | | | Move a long comment from lib/crc32.c to Documentation/crc32.txt where it will more likely get read. Edited the resulting document to add an explanation of the slicing-by-n algorithm. [djwong@us.ibm.com: minor changelog tweaks] [akpm@linux-foundation.org: fix typo, per George] Signed-off-by: George Spelvin <linux@horizon.com> Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crc32: remove two instances of trailing whitespacesBob Pearson2012-03-232-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patchset (re)uses Bob Pearson's crc32 slice-by-8 code to stamp out a software crc32c implementation. It removes the crc32c implementation in crypto/ in favor of using the stamped-out one in lib/. There is also a change to Kconfig so that the kernel builder can pick an implementation best suited for the hardware. The motivation for this patchset is that I am working on adding full metadata checksumming to ext4. As far as performance impact of adding checksumming goes, I see nearly no change with a standard mail server ffsb simulation. On a test that involves only file creation and deletion and extent tree writes, I see a drop of about 50 pcercent with the current kernel crc32c implementation; this improves to a drop of about 20 percent with the enclosed crc32c code. When metadata is usually a small fraction of total IO, this new implementation doesn't help much because metadata is usually a small fraction of total IO. However, when we are doing IO that is almost all metadata (such as rm -rf'ing a tree), then this patch speeds up the operation substantially. Incidentally, given that iscsi, sctp, and btrfs also use crc32c, this patchset should improve their speed as well. I have not yet quantified that, however. This latest submission combines Bob's patches from late August 2011 with mine so that they can be one coherent patch set. Please excuse my inability to combine some of the patches; I've been advised to leave Bob's patches alone and build atop them instead. :/ Since the last posting, I've also collected some crc32c test results on a bunch of different x86/powerpc/sparc platforms. The results can be viewed here: http://goo.gl/sgt3i ; the "crc32-kern-le" and "crc32c" columns describe the performance of the kernel's current crc32 and crc32c software implementations. The "crc32c-by8-le" column shows crc32c performance with this patchset applied. I expect crc32 performance to be roughly the same. The two _boost columns at the right side of the spreadsheet shows how much faster the new implementation is over the old one. As you can see, crc32 rises substantially, and crc32c experiences a huge increase. This patch: - remove trailing whitespace from lib/crc32.c - remove trailing whitespace from lib/crc32defs.h [djwong@us.ibm.com: changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* prio_tree: introduce prio_set_parent()Xiao Guangrong2012-03-231-25/+22
| | | | | | | | | Introduce prio_set_parent() to abstract the operation which is used to attach the node to its parent. Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* prio_tree: simplify prio_tree_expand()Xiao Guangrong2012-03-231-24/+14
| | | | | | | | | | In current code, the deleted-node is recorded from first to last, actually, we can directly attach these node on 'node' we will insert as the left child, it can let the code more readable. Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* prio_tree: cleanup prio_tree_left()/prio_tree_right()Xiao Guangrong2012-03-231-41/+37
| | | | | | | | | Introduce iter_walk_down()/iter_walk_up() to remove the common code between prio_tree_left() and prio_tree_right(). Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* prio_tree: remove unnecessary code in prio_tree_replaceXiao Guangrong2012-03-231-1/+0
| | | | | | | | | Remove the code since 'node' has already been initialized in the begin of the function Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* string: memchr_inv() speed improvementsAkinobu Mita2012-03-231-4/+16
| | | | | | | | | | | | | | | | | | | | | | | - Generate a 64-bit pattern more efficiently memchr_inv needs to generate a 64-bit pattern filled with a target character. The operation can be done by more efficient way. - Don't call the slow check_bytes() if the memory area is 64-bit aligned memchr_inv compares contiguous 64-bit words with the 64-bit pattern as much as possible. The outside of the region is checked by check_bytes() that scans for each byte. Unfortunately, the first 64-bit word is unexpectedly scanned by check_bytes() even if the memory area is aligned to a 64-bit boundary. Both changes were originally suggested by Eric Dumazet. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* nmi watchdog: do not use cpp symbol in KconfigCong Wang2012-03-231-1/+1
| | | | | | | | | | | | | | | ARCH_HAS_NMI_WATCHDOG is a macro defined by arch, but config HARDLOCKUP_DETECTOR depends on it. This is wrong, ARCH_HAS_NMI_WATCHDOG has to be a Kconfig config, and arch's need it should select it explicitly. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Acked-by: Don Zickus <dzickus@redhat.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Cc: David Howells <dhowells@redhat.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* idr: make idr_get_next() good for rcu_read_lock()Hugh Dickins2012-03-211-3/+5
| | | | | | | | | | | | | | | Make one small adjustment to idr_get_next(): take the height from the top layer (stable under RCU) instead of from the root (unprotected by RCU), as idr_find() does: so that it can be used with RCU locking. Copied comment on RCU locking from idr_find(). Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'kmap_atomic' of git://github.com/congwang/linuxLinus Torvalds2012-03-212-5/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kmap_atomic cleanup from Cong Wang. It's been in -next for a long time, and it gets rid of the (no longer used) second argument to k[un]map_atomic(). Fix up a few trivial conflicts in various drivers, and do an "evil merge" to catch some new uses that have come in since Cong's tree. * 'kmap_atomic' of git://github.com/congwang/linux: (59 commits) feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename] drbd: remove the second argument of k[un]map_atomic() zcache: remove the second argument of k[un]map_atomic() gma500: remove the second argument of k[un]map_atomic() dm: remove the second argument of k[un]map_atomic() tomoyo: remove the second argument of k[un]map_atomic() sunrpc: remove the second argument of k[un]map_atomic() rds: remove the second argument of k[un]map_atomic() net: remove the second argument of k[un]map_atomic() mm: remove the second argument of k[un]map_atomic() lib: remove the second argument of k[un]map_atomic() power: remove the second argument of k[un]map_atomic() kdb: remove the second argument of k[un]map_atomic() udf: remove the second argument of k[un]map_atomic() ubifs: remove the second argument of k[un]map_atomic() squashfs: remove the second argument of k[un]map_atomic() reiserfs: remove the second argument of k[un]map_atomic() ocfs2: remove the second argument of k[un]map_atomic() ntfs: remove the second argument of k[un]map_atomic() ...
| * lib: remove the second argument of k[un]map_atomic()Cong Wang2012-03-202-5/+4
| | | | | | | | Signed-off-by: Cong Wang <amwang@redhat.com>
* | Merge tag 'driver-core-3.3' of ↵Linus Torvalds2012-03-203-95/+197
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches for 3.4-rc1 from Greg KH: "Here's the big driver core merge for 3.4-rc1. Lots of various things here, sysfs fixes/tweaks (with the nlink breakage reverted), dynamic debugging updates, w1 drivers, hyperv driver updates, and a variety of other bits and pieces, full information in the shortlog." * tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (78 commits) Tools: hv: Support enumeration from all the pools Tools: hv: Fully support the new KVP verbs in the user level daemon Drivers: hv: Support the newly introduced KVP messages in the driver Drivers: hv: Add new message types to enhance KVP regulator: Support driver probe deferral Revert "sysfs: Kill nlink counting." uevent: send events in correct order according to seqnum (v3) driver core: minor comment formatting cleanups driver core: move the deferred probe pointer into the private area drivercore: Add driver probe deferral mechanism DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave drivers w1_bq27000: Only one thread can access the bq27000 at a time. w1_bq27000 - remove w1_bq27000_write w1_bq27000: remove unnecessary NULL test. sysfs: Fix memory leak in sysfs_sd_setsecdata(). intel_idle: Revert change of auto_demotion_disable_flags for Nehalem w1: Fix w1_bq27000 driver-core: documentation: fix up Greg's email address powernow-k6: Really enable auto-loading powernow-k7: Fix CPU family number ...
| * \ Merge 3.3-rc6 into driver-core-nextGreg Kroah-Hartman2012-03-0914-157/+114
| |\ \ | | | | | | | | | | | | | | | | | | | | This was done to resolve a conflict in the drivers/base/cpu.c file. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | uevent: send events in correct order according to seqnum (v3)Andrew Vagin2012-03-081-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The queue handling in the udev daemon assumes that the events are ordered. Before this patch uevent_seqnum is incremented under sequence_lock, than an event is send uner uevent_sock_mutex. I want to say that code contained a window between incrementing seqnum and sending an event. This patch locks uevent_sock_mutex before incrementing uevent_seqnum. v2: delete sequence_lock, uevent_seqnum is protected by uevent_sock_mutex v3: unlock the mutex before the goto exit Thanks for Kay for the comments. Signed-off-by: Andrew Vagin <avagin@openvz.org> Tested-By: Kay Sievers <kay.sievers@vrfy.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | Remove useless get_driver()/put_driver() callsAlan Stern2012-01-241-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As part of the removal of get_driver()/put_driver(), this patch (as1512) gets rid of various useless and unnecessary calls in several drivers. In some cases it may be desirable to pin the driver by calling try_module_get(), but that can be done later. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: "David S. Miller" <davem@davemloft.net> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: Michael Buesch <m@bues.ch> CC: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: process multiple debug-queries on a lineJim Cromie2012-01-241-15/+58
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Insert ddebug_exec_queries() in place of ddebug_exec_query(). It splits the query string on [;\n], and calls ddebug_exec_query() on each. All queries are processed independent of errors, allowing a query to fail, for example when a module is not installed. Empty lines and comments are skipped. Errors are counted, and the last error seen (negative) or the number of callsites found (0 or positive) is returned. Return code checks are altered accordingly. With this, multiple queries can be given in ddebug_query, allowing more selective enabling of callsites. As a side effect, a set of commands can be batched in: cat cmd-file > $DBGMT/dynamic_debug/control We dont want a ddebug_query syntax error to kill the dynamic debug facility, so dynamic_debug_init() zeros ddebug_exec_queries()'s return code after logging the appropriate message, so that ddebug tables are preserved and $DBGMT/dynamic_debug/control file is created. This would be appropriate even without accepting multiple queries. This patch also alters ddebug_change() to return number of callsites matched (which typically is the same as number of callsites changed). ddebug_exec_query() also returns the number found, or a negative value if theres a parse error on the query. Splitting on [;\n] prevents their use in format-specs, but selecting callsites on punctuation is brittle anyway, meaningful and selective substrings are more typical. Note: splitting queries on ';' before handling trailing #comments means that a ';' also terminates a comment, and text after the ';' is treated as another query. This trailing query will almost certainly result in a parse error and thus have no effect other than the error message. The double corner case with unexpected results is: ddebug_query="func foo +p # enable foo ; +p" Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: factor vpr_info_dq out of ddebug_parse_queryJim Cromie2012-01-241-8/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Factor pr_info(query) out of ddebug_parse_query, into vpr_info_dq(), for reuse later. Also change the printed labels: file, func to agree with the query-spec keywords accepted in the control file. Pass "" when string is null, to avoid "(null)" output from sprintf. For format print, use precision to skip last char, assuming its '\n', no great harm if not, its a debug msg. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: add trim_prefix() to provide source-root relative pathsJim Cromie2012-01-241-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | trim_prefix(path) skips past the absolute source path root, and returns the pointer to the relative path from there. It is used to shorten the displayed path in $DBGMT/dynamic_debug/control via ddebug_proc_show(), and in ddebug_change() to allow relative filenames to be used in applied queries. For example: ~# echo file kernel/freezer.c +p > $DBGMT/dynamic_debug/control kernel/freezer.c:128 [freezer]cancel_freezing p " clean up: %s\012" trim_prefix(path) insures common prefix before trimming it, so out-of-tree module paths are shown as full absolute paths. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: enlarge command/query write bufferJim Cromie2012-01-241-4/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current query write buffer is 256 bytes, on stack. In comparison, the ddebug_query boot-arg is 1024. Allocate the buffer off heap, and enlarge it to 4096 bytes, big enough for ~100 queries (at 40 bytes each), and error out if not. This makes it play nicely with large query sets (to be added later). The buffer should be enough for most uses, and others should probably be split into subsets. [jbaron@redhat.com: changed USER_BUF_PAGE from 4095 -> 4096 ] Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: chop off comments in ddebug_tokenizeJim Cromie2012-01-241-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a token begins with #, the remainder of query string is a comment, so drop it. Doing it here avoids '#' in quoted strings. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: early return if _ddebug table is emptyJim Cromie2012-01-241-15/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If _ddebug table is empty (in a CONFIG_DYNAMIC_DEBUG build this shouldn't happen), then warn (error?) and return early. This skips empty table scan and parsing of setup-string, including the pr_info call noting the parse. By inspection, copy return-code handling from 1st ddebug_add_module() callsite to 2nd. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: tighten up error checking on debug queriesJim Cromie2012-01-241-6/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Issue error when a match-spec is given multiple times in a rule. Previous code kept last one, but was silent about it. Docs imply only one is allowed by saying match-specs are ANDed together, given that module M cannot match both A and B. Also error when last_line < 1st_line. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: describe_flags with '=[pmflt_]*'Jim Cromie2012-01-241-11/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change describe_flags() to emit '=[pmflt_]+' for current callsite flags, or just '=_' when they're disabled. Having '=' in output allows a more selective grep expression; in contrast '-' may appear in filenames, line-ranges, and format-strings. '=' also has better mnemonics, saying; "the current setting is equal to <flags>". This allows grep "=_" <dbgfs>/dynamic_debug/control to see disabled callsites while avoiding the many occurrences of " = " seen in format strings. Enlarge flagsbufs to handle additional flag char, and alter ddebug_parse_flags() to allow flags=0, so that user can turn off all debug flags via: ~# echo =_ > <dbgfs>/dynamic_debug/control Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: drop explicit !=NULL checksJim Cromie2012-01-241-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert 'if (x !=NULL)' checks into 'if (x)'. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: pr_err() call should not depend upon verbosityJim Cromie2012-01-241-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Issue keyword/parsing errors even w/o verbose set; uncover otherwize mysterious non-functionality. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: replace strcpy with strlcpy, in ddebug_setup_query()Jim Cromie2012-01-241-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace strcpy with strlcpy, and add define for the size constant. [jbaron@redhat.com: Use DDEBUG_STRING_SIZE for overflow check] Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: change verbosity at runtimeJim Cromie2012-01-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow changing dynamic_debug verbosity at run-time, to ease debugging of ddebug queries as you add them, improving usability. at boot time: dynamic_debug.verbose=1 at runtime: root@voyage:~# echo 1 > /sys/module/dynamic_debug/parameters/verbose Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: drop enabled field from struct _ddebug, use _DPRINTK_FLAGS_PRINTJim Cromie2012-01-241-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently any enabled dynamic-debug flag on a pr_debug callsite will enable printing, even if _DPRINTK_FLAGS_PRINT is off. Checking print flag directly allows "-p" to disable callsites without fussing with other flags, so the following disables everything, without altering flags user may have set: echo -p > $DBGFS/dynamic_debug/control Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | dynamic_debug: fix whitespace complaints from scripts/cleanfileJim Cromie2012-01-241-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Style cleanups. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | | | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2012-03-201-7/+11
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events changes for v3.4 from Ingo Molnar: - New "hardware based branch profiling" feature both on the kernel and the tooling side, on CPUs that support it. (modern x86 Intel CPUs with the 'LBR' hardware feature currently.) This new feature is basically a sophisticated 'magnifying glass' for branch execution - something that is pretty difficult to extract from regular, function histogram centric profiles. The simplest mode is activated via 'perf record -b', and the result looks like this in perf report: $ perf record -b any_call,u -e cycles:u branchy $ perf report -b --sort=symbol 52.34% [.] main [.] f1 24.04% [.] f1 [.] f3 23.60% [.] f1 [.] f2 0.01% [k] _IO_new_file_xsputn [k] _IO_file_overflow 0.01% [k] _IO_vfprintf_internal [k] _IO_new_file_xsputn 0.01% [k] _IO_vfprintf_internal [k] strchrnul 0.01% [k] __printf [k] _IO_vfprintf_internal 0.01% [k] main [k] __printf This output shows from/to branch columns and shows the highest percentage (from,to) jump combinations - i.e. the most likely taken branches in the system. "branches" can also include function calls and any other synchronous and asynchronous transitions of the instruction pointer that are not 'next instruction' - such as system calls, traps, interrupts, etc. This feature comes with (hopefully intuitive) flat ascii and TUI support in perf report. - Various 'perf annotate' visual improvements for us assembly junkies. It will now recognize function calls in the TUI and by hitting enter you can follow the call (recursively) and back, amongst other improvements. - Multiple threads/processes recording support in perf record, perf stat, perf top - which is activated via a comma-list of PIDs: perf top -p 21483,21485 perf stat -p 21483,21485 -ddd perf record -p 21483,21485 - Support for per UID views, via the --uid paramter to perf top, perf report, etc. For example 'perf top --uid mingo' will only show the tasks that I am running, excluding other users, root, etc. - Jump label restructurings and improvements - this includes the factoring out of the (hopefully much clearer) include/linux/static_key.h generic facility: struct static_key key = STATIC_KEY_INIT_FALSE; ... if (static_key_false(&key)) do unlikely code else do likely code ... static_key_slow_inc(); ... static_key_slow_inc(); ... The static_key_false() branch will be generated into the code with as little impact to the likely code path as possible. the static_key_slow_*() APIs flip the branch via live kernel code patching. This facility can now be used more widely within the kernel to micro-optimize hot branches whose likelihood matches the static-key usage and fast/slow cost patterns. - SW function tracer improvements: perf support and filtering support. - Various hardenings of the perf.data ABI, to make older perf.data's smoother on newer tool versions, to make new features integrate more smoothly, to support cross-endian recording/analyzing workflows better, etc. - Restructuring of the kprobes code, the splitting out of 'optprobes', and a corner case bugfix. - Allow the tracing of kernel console output (printk). - Improvements/fixes to user-space RDPMC support, allowing user-space self-profiling code to extract PMU counts without performing any system calls, while playing nice with the kernel side. - 'perf bench' improvements - ... and lots of internal restructurings, cleanups and fixes that made these features possible. And, as usual this list is incomplete as there were also lots of other improvements * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits) perf report: Fix annotate double quit issue in branch view mode perf report: Remove duplicate annotate choice in branch view mode perf/x86: Prettify pmu config literals perf report: Enable TUI in branch view mode perf report: Auto-detect branch stack sampling mode perf record: Add HEADER_BRANCH_STACK tag perf record: Provide default branch stack sampling mode option perf tools: Make perf able to read files from older ABIs perf tools: Fix ABI compatibility bug in print_event_desc() perf tools: Enable reading of perf.data files from different ABI rev perf: Add ABI reference sizes perf report: Add support for taken branch sampling perf record: Add support for sampling taken branch perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK x86/kprobes: Split out optprobe related code to kprobes-opt.c x86/kprobes: Fix a bug which can modify kernel code permanently x86/kprobes: Fix instruction recovery on optimized path perf: Add callback to flush branch_stack on context switch perf: Disable PERF_SAMPLE_BRANCH_* when not supported perf/x86: Add LBR software filter support for Intel CPUs ...
| * \ \ \ Merge branch 'perf/urgent' into perf/coreIngo Molnar2012-03-122-14/+12
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge reason: We are going to queue up a dependent patch. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * \ \ \ \ Merge branch 'perf/urgent' into perf/coreIngo Molnar2012-03-053-6/+17
| |\ \ \ \ \ | | | |_|/ / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: tools/perf/builtin-record.c tools/perf/builtin-top.c tools/perf/perf.h tools/perf/util/top.h Merge reason: resolve these cherry-picking conflicts. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | watchdog: Update Kconfig entriesFernando Luis Vázquez Cao2012-02-111-7/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The soft and hard lockup thresholds have changed so the corresponding Kconfig entries need to be updated accordingly. Add a reference to watchdog_thresh while at it. Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Don Zickus <dzickus@redhat.com> Link: http://lkml.kernel.org/r/1328827342-6253-2-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | | Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds2012-03-201-0/+24
|\ \ \ \ \ \ | |_|_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes for v3.4 from Ingo Molnar. The major features of this series are: - making RCU more aggressive about entering dyntick-idle mode in order to improve energy efficiency - converting a few more call_rcu()s to kfree_rcu()s - applying a number of rcutree fixes and cleanups to rcutiny - removing CONFIG_SMP #ifdefs from treercu - allowing RCU CPU stall times to be set via sysfs - adding CPU-stall capability to rcutorture - adding more RCU-abuse diagnostics - updating documentation - fixing yet more issues located by the still-ongoing top-to-bottom inspection of RCU, this time with a special focus on the CPU-hotplug code path. * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits) rcu: Stop spurious warnings from synchronize_sched_expedited rcu: Hold off RCU_FAST_NO_HZ after timer posted rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit() rcu: Remove redundant check for rcu_head misalignment PTR_ERR should be called before its argument is cleared. rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep rcu: Trace only after NULL-pointer check rcu: Call out dangers of expedited RCU primitives rcu: Rework detection of use of RCU by offline CPUs lockdep: Add CPU-idle/offline warning to lockdep-RCU splat rcu: No interrupt disabling for rcu_prepare_for_idle() rcu: Move synchronize_sched_expedited() to rcutree.c rcu: Check for illegal use of RCU from offlined CPUs rcu: Update stall-warning documentation rcu: Add CPU-stall capability to rcutorture rcu: Make documentation give more realistic rcutorture duration rcutorture: Permit holding off CPU-hotplug operations during boot rcu: Print scheduling-clock information on RCU CPU stall-warning messages ...
| * | | | | rcu: Print scheduling-clock information on RCU CPU stall-warning messagesPaul E. McKenney2012-02-211-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There have been situations where RCU CPU stall warnings were caused by issues in scheduling-clock timer initialization. To make it easier to track these down, this commit causes the RCU CPU stall-warning messages to print out the number of scheduling-clock interrupts taken in the current grace period for each stalled CPU. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| * | | | | rcu: Move RCU_TRACE to lib/Kconfig.debugPaul E. McKenney2012-02-211-0/+10
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The RCU_TRACE kernel parameter has always been intended for debugging, not for production use. Formalize this by moving RCU_TRACE from init/Kconfig to lib/Kconfig.debug. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | | | | dql: Fix undefined jiffiesTom Herbert2012-03-111-0/+1
| |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some configurations, jiffies may be undefined in lib/dynamic_queue_limits.c. Adding include of jiffies.h to avoid this. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | vsprintf: make %pV handling compatible with kasprintf()Jan Beulich2012-03-061-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kasprintf() (and potentially other functions that I didn't run across so far) want to evaluate argument lists twice. Caring to do so for the primary list is obviously their job, but they can't reasonably be expected to check the format string for instances of %pV, which however need special handling too: On architectures like x86-64 (as opposed to e.g. ix86), using the same argument list twice doesn't produce the expected results, as an internally managed cursor gets updated during the first run. Fix the problem by always acting on a copy of the original list when handling %pV. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | debugobjects: Fix selftest for static warningsStephen Boyd2012-03-051-11/+3
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | debugobjects is now printing a warning when a fixup for a NOTAVAILABLE object is run. This causes the selftest to fail like: ODEBUG: selftest warnings failed 4 != 5 We could just increase the number of warnings that the selftest is expecting to see because that is actually what has changed. But, it turns out that fixup_activate() was written with inverted logic and thus a fixup for a static object returned 1 indicating the object had been fixed, and 0 otherwise. Fix the logic to be correct and update the counts to reflect that nothing needed fixing for a static object. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Reduce the number of expensive division instructions done by _parse_integer()David Howells2012-02-091-5/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | _parse_integer() does one or two division instructions (which are slow) per digit parsed to perform the overflow check. Furthermore, these are particularly expensive examples of division instruction as the number of clock cycles required to complete them may go up with the position of the most significant set bit in the dividend: if (*res > div_u64(ULLONG_MAX - val, base)) which is as maximal as possible. Worse, on 32-bit arches, more than one of these division instructions may be required per digit. So, assuming we don't support a base of more than 16, skip the check if the top nibble of the result is not set at this point. Signed-off-by: David Howells <dhowells@redhat.com> [ Changed it to not dereference the pointer all the time - even if the compiler can and does optimize it away, the code just looks cleaner. And edited the top nybble test slightly to make the code generated on x86-64 better in the loop - test against a hoisted constant instead of shifting and testing the result ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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