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2013-11-08kernel: trace: blktrace: remove redundent memcpy() in compat_blk_trace_setup()Chen Gang
do_blk_trace_setup() will fully initialize 'buts.name', so can remove the related memcpy(). And also use BLKTRACE_BDEV_SIZE and ARRAY_SIZE instead of hard code number '32'. Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-11-08blktrace: Send BLK_TN_PROCESS events to all running tracesJan Kara
Currently each task sends BLK_TN_PROCESS event to the first traced device it interacts with after a new trace is started. When there are several traced devices and the task accesses more devices, this logic can result in BLK_TN_PROCESS being sent several times to some devices while it is never sent to other devices. Thus blkparse doesn't display command name when parsing some blktrace files. Fix the problem by sending BLK_TN_PROCESS event to all traced devices when a task interacts with any of them. Signed-off-by: Jan Kara <jack@suse.cz> Review-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-05-08Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "It might look big in volume, but when categorized, not a lot of drivers are touched. The pull request contains: - mtip32xx fixes from Micron. - A slew of drbd updates, this time in a nicer series. - bcache, a flash/ssd caching framework from Kent. - Fixes for cciss" * 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits) bcache: Use bd_link_disk_holder() bcache: Allocator cleanup/fixes cciss: bug fix to prevent cciss from loading in kdump crash kernel cciss: add cciss_allow_hpsa module parameter drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions mtip32xx: Workaround for unaligned writes bcache: Make sure blocksize isn't smaller than device blocksize bcache: Fix merge_bvec_fn usage for when it modifies the bvm bcache: Correctly check against BIO_MAX_PAGES bcache: Hack around stuff that clones up to bi_max_vecs bcache: Set ra_pages based on backing device's ra_pages bcache: Take data offset from the bdev superblock. mtip32xx: mtip32xx: Disable TRIM support mtip32xx: fix a smatch warning bcache: Disable broken btree fuzz tester bcache: Fix a format string overflow bcache: Fix a minor memory leak on device teardown bcache: Documentation updates bcache: Use WARN_ONCE() instead of __WARN() bcache: Add missing #include <linux/prefetch.h> ...
2013-04-29Merge tag 'trace-3.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "Along with the usual minor fixes and clean ups there are a few major changes with this pull request. 1) Multiple buffers for the ftrace facility This feature has been requested by many people over the last few years. I even heard that Google was about to implement it themselves. I finally had time and cleaned up the code such that you can now create multiple instances of the ftrace buffer and have different events go to different buffers. This way, a low frequency event will not be lost in the noise of a high frequency event. Note, currently only events can go to different buffers, the tracers (ie function, function_graph and the latency tracers) still can only be written to the main buffer. 2) The function tracer triggers have now been extended. The function tracer had two triggers. One to enable tracing when a function is hit, and one to disable tracing. Now you can record a stack trace on a single (or many) function(s), take a snapshot of the buffer (copy it to the snapshot buffer), and you can enable or disable an event to be traced when a function is hit. 3) A perf clock has been added. A "perf" clock can be chosen to be used when tracing. This will cause ftrace to use the same clock as perf uses, and hopefully this will make it easier to interleave the perf and ftrace data for analysis." * tag 'trace-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (82 commits) tracepoints: Prevent null probe from being added tracing: Compare to 1 instead of zero for is_signed_type() tracing: Remove obsolete macro guard _TRACE_PROFILE_INIT ftrace: Get rid of ftrace_profile_bits tracing: Check return value of tracing_init_dentry() tracing: Get rid of unneeded key calculation in ftrace_hash_move() tracing: Reset ftrace_graph_filter_enabled if count is zero tracing: Fix off-by-one on allocating stat->pages kernel: tracing: Use strlcpy instead of strncpy tracing: Update debugfs README file tracing: Fix ftrace_dump() tracing: Rename trace_event_mutex to trace_event_sem tracing: Fix comment about prefix in arch_syscall_match_sym_name() tracing: Convert trace_destroy_fields() to static tracing: Move find_event_field() into trace_events.c tracing: Use TRACE_MAX_PRINT instead of constant tracing: Use pr_warn_once instead of open coded implementation ring-buffer: Add ring buffer startup selftest tracing: Bring Documentation/trace/ftrace.txt up to date tracing: Add "perf" trace_clock ... Conflicts: kernel/trace/ftrace.c kernel/trace/trace.c
2013-04-18Revert "block: add missing block_bio_complete() tracepoint"Linus Torvalds
This reverts commit 3a366e614d0837d9fc23f78cdb1a1186ebc3387f. Wanlong Gao reports that it causes a kernel panic on his machine several minutes after boot. Reverting it removes the panic. Jens says: "It's not quite clear why that is yet, so I think we should just revert the commit for 3.9 final (which I'm assuming is pretty close). The wifi is crap at the LSF hotel, so sending this email instead of queueing up a revert and pull request." Reported-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Requested-by: Jens Axboe <axboe@kernel.dk> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-03-23Export blk_fill_rwbs()Kent Overstreet
Exported so it can be used by bcache's tracepoints Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Steven Rostedt <rostedt@goodmis.org> CC: Frederic Weisbecker <fweisbec@gmail.com> CC: Ingo Molnar <mingo@redhat.com>
2013-03-15tracing: Consolidate max_tr into main trace_array structureSteven Rostedt (Red Hat)
Currently, the way the latency tracers and snapshot feature works is to have a separate trace_array called "max_tr" that holds the snapshot buffer. For latency tracers, this snapshot buffer is used to swap the running buffer with this buffer to save the current max latency. The only items needed for the max_tr is really just a copy of the buffer itself, the per_cpu data pointers, the time_start timestamp that states when the max latency was triggered, and the cpu that the max latency was triggered on. All other fields in trace_array are unused by the max_tr, making the max_tr mostly bloat. This change removes the max_tr completely, and adds a new structure called trace_buffer, that holds the buffer pointer, the per_cpu data pointers, the time_start timestamp, and the cpu where the latency occurred. The trace_array, now has two trace_buffers, one for the normal trace and one for the max trace or snapshot. By doing this, not only do we remove the bloat from the max_trace but the instances of traces can now use their own snapshot feature and not have just the top level global_trace have the snapshot feature and latency tracers for itself. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-02-28Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block IO core bits from Jens Axboe: "Below are the core block IO bits for 3.9. It was delayed a few days since my workstation kept crashing every 2-8h after pulling it into current -git, but turns out it is a bug in the new pstate code (divide by zero, will report separately). In any case, it contains: - The big cfq/blkcg update from Tejun and and Vivek. - Additional block and writeback tracepoints from Tejun. - Improvement of the should sort (based on queues) logic in the plug flushing. - _io() variants of the wait_for_completion() interface, using io_schedule() instead of schedule() to contribute to io wait properly. - Various little fixes. You'll get two trivial merge conflicts, which should be easy enough to fix up" Fix up the trivial conflicts due to hlist traversal cleanups (commit b67bfe0d42ca: "hlist: drop the node parameter from iterators"). * 'for-3.9/core' of git://git.kernel.dk/linux-block: (39 commits) block: remove redundant check to bd_openers() block: use i_size_write() in bd_set_size() cfq: fix lock imbalance with failed allocations drivers/block/swim3.c: fix null pointer dereference block: don't select PERCPU_RWSEM block: account iowait time when waiting for completion of IO request sched: add wait_for_completion_io[_timeout] writeback: add more tracepoints block: add block_{touch|dirty}_buffer tracepoint buffer: make touch_buffer() an exported function block: add @req to bio_{front|back}_merge tracepoints block: add missing block_bio_complete() tracepoint block: Remove should_sort judgement when flush blk_plug block,elevator: use new hashtable implementation cfq-iosched: add hierarchical cfq_group statistics cfq-iosched: collect stats from dead cfqgs cfq-iosched: separate out cfqg_stats_reset() from cfq_pd_reset_stats() blkcg: make blkcg_print_blkgs() grab q locks instead of blkcg lock block: RCU free request_queue blkcg: implement blkg_[rw]stat_recursive_sum() and blkg_[rw]stat_merge() ...
2013-01-21tracing: Use this_cpu_ptr per-cpu helperShan Wei
typeof(&buffer) is a pointer to array of 1024 char, or char (*)[1024]. But, typeof(&buffer[0]) is a pointer to char which match the return type of get_trace_buf(). As well-known, the value of &buffer is equal to &buffer[0]. so return this_cpu_ptr(&percpu_buffer->buffer[0]) can avoid type cast. Link: http://lkml.kernel.org/r/50A1A800.3020102@gmail.com Reviewed-by: Christoph Lameter <cl@linux.com> Signed-off-by: Shan Wei <davidshan@tencent.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-01-14block: add @req to bio_{front|back}_merge tracepointsTejun Heo
bio_{front|back}_merge tracepoints report a bio merging into an existing request but didn't specify which request the bio is being merged into. Add @req to it. This makes it impossible to share the event template with block_bio_queue - split it out. @req isn't used or exported to userland at this point and there is no userland visible behavior change. Later changes will make use of the extra parameter. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-01-14block: add missing block_bio_complete() tracepointTejun Heo
bio completion didn't kick block_bio_complete TP. Only dm was explicitly triggering the TP on IO completion. This makes block_bio_complete TP useless for tracers which want to know about bios, and all other bio based drivers skip generating blktrace completion events. This patch makes all bio completions via bio_endio() generate block_bio_complete TP. * Explicit trace_block_bio_complete() invocation removed from dm and the trace point is unexported. * @rq dropped from trace_block_bio_complete(). bios may fly around w/o queue associated. Verifying and accessing the assocaited queue belongs to TP probes. * blktrace now gets both request and bio completions. Make it ignore bio completions if request completion path is happening. This makes all bio based drivers generate blktrace completion events properly and makes the block_bio_complete TP actually useful. v2: With this change, block_bio_complete TP could be invoked on sg commands which have bio's with %NULL bi_bdev. Update TP assignment code to check whether bio->bi_bdev is %NULL before dereferencing. Signed-off-by: Tejun Heo <tj@kernel.org> Original-patch-by: Namhyung Kim <namhyung@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alasdair Kergon <agk@redhat.com> Cc: dm-devel@redhat.com Cc: Neil Brown <neilb@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-05simple_open: automatically convert to simple_open()Stephen Boyd
Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: <smpl> @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; </smpl> [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-03switch debugfs to umode_tAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-10-31kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructurePaul Gortmaker
These files were getting <linux/module.h> via an implicit non-obvious path, but we want to crush those out of existence since they cost time during compiles of processing thousands of lines of headers for no reason. Give them the lightweight header that just contains the EXPORT_SYMBOL infrastructure. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-08-11blktrace: add FLUSH/FUA supportNamhyung Kim
Add FLUSH/FUA support to blktrace. As FLUSH precedes WRITE and/or FUA follows WRITE, use the same 'F' flag for both cases and distinguish them by their (relative) position. The end results look like (other flags might be shown also): - WRITE: W - WRITE_FLUSH: FW - WRITE_FUA: WF - WRITE_FLUSH_FUA: FWF Note that we reuse TC_BARRIER due to lack of bit space of act_mask so that the older versions of blktrace tools will report flush requests as barriers from now on. Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Namhyung Kim <namhyung@gmail.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-16block: make unplug timer trace event correspond to the schedule() unplugJens Axboe
It's a pretty close match to what we had before - the timer triggering would mean that nobody unplugged the plug in due time, in the new scheme this matches very closely what the schedule() unplug now is. It's essentially the difference between an explicit unplug (IO unplug) or an implicit unplug (timer unplug, we scheduled with pending IO queued). Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-12block: fixup block IO unplug trace callJens Axboe
It was removed with the on-stack plugging, readd it and track the depth of requests added when flushing the plug. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-12block: remove block_unplug_timer() trace pointJens Axboe
We no longer have an unplug timer running, so no point in keeping the trace point. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-11blktrace: Use rq->cmd_flags directly in blk_add_trace_rq.Tao Ma
In blk_add_trace_rq, we only chose the minor 2 bits from request's cmd_flags and did some check for discard. so most of other flags(e.g, REQ_SYNC) are missing. For example, with a sync write after blkparse we get: 8,16 1 1 0.001776503 7509 A WS 1349632 + 1024 <- (8,17) 1347584 8,16 1 2 0.001776813 7509 Q WS 1349632 + 1024 [dd] 8,16 1 3 0.001780395 7509 G WS 1349632 + 1024 [dd] 8,16 1 5 0.001783186 7509 I W 1349632 + 1024 [dd] 8,16 1 11 0.001816987 7509 D W 1349632 + 1024 [dd] 8,16 0 2 0.006218192 0 C W 1349632 + 1024 [0] Since now we have integrated the flags of both bio and request, it is safe to pass rq->cmd_flags directly to __blk_add_trace. With this patch, after a sync write we get: 8,16 1 1 0.001776900 5425 A WS 1189888 + 1024 <- (8,17) 1187840 8,16 1 2 0.001777179 5425 Q WS 1189888 + 1024 [dd] 8,16 1 3 0.001780797 5425 G WS 1189888 + 1024 [dd] 8,16 1 5 0.001783402 5425 I WS 1189888 + 1024 [dd] 8,16 1 11 0.001817468 5425 D WS 1189888 + 1024 [dd] 8,16 0 2 0.005640709 0 C WS 1189888 + 1024 [0] Signed-off-by: Tao Ma <boyu.mt@taobao.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-03blktrace: Remove blk_fill_rwbs_rq.Tao Ma
If we enable trace events to trace block actions, We use blk_fill_rwbs_rq to analyze the corresponding actions in request's cmd_flags, but we only choose the minor 2 bits from it, so most of other flags(e.g, REQ_SYNC) are missing. For example, with a sync write we get: write_test-2409 [001] 160.013869: block_rq_insert: 3,64 W 0 () 258135 + = 8 [write_test] Since now we have integrated the flags of both bio and request, it is safe to pass rq->cmd_flags directly to blk_fill_rwbs and blk_fill_rwbs_rq isn't needed any more. With this patch, after a sync write we get: write_test-2417 [000] 226.603878: block_rq_insert: 3,64 WS 0 () 258135 += 8 [write_test] Signed-off-by: Tao Ma <boyu.mt@taobao.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-19blktrace: Don't output messages if NOTIFY isn't set.Tao Ma
Now if we enable blktrace, cfq has too many messages output to the trace buffer. It is fine if we don't specify any action mask. But if I do like this: blktrace /dev/sdb -a issue -a complete -o - | blkparse -i - I only want to see 'D' and 'C', while with the following command dd if=/mnt/ocfs2/test of=/dev/null bs=4k count=1 iflag=direct I will get(with a 2.6.37 vanilla kernel): 8,16 0 0 0.000000000 0 m N cfq3805 alloced 8,16 0 0 0.000004126 0 m N cfq3805 insert_request 8,16 0 0 0.000004884 0 m N cfq3805 add_to_rr 8,16 0 0 0.000008417 0 m N cfq workload slice:300 8,16 0 0 0.000009557 0 m N cfq3805 set_active wl_prio:0 wl_type:2 8,16 0 0 0.000010640 0 m N cfq3805 fifo= (null) 8,16 0 0 0.000011193 0 m N cfq3805 dispatch_insert 8,16 0 0 0.000012221 0 m N cfq3805 dispatched a request 8,16 0 0 0.000012802 0 m N cfq3805 activate rq, drv=1 8,16 0 1 0.000013181 3805 D R 114759 + 8 [dd] 8,16 0 2 0.000164244 0 C R 114759 + 8 [0] 8,16 0 0 0.000167997 0 m N cfq3805 complete rqnoidle 0 8,16 0 0 0.000168782 0 m N cfq3805 set_slice=100 8,16 0 0 0.000169874 0 m N cfq3805 arm_idle: 8 group_idle: 0 8,16 0 0 0.000170189 0 m N cfq schedule dispatch 8,16 0 0 0.000397938 0 m N cfq3805 slice expired t=0 8,16 0 0 0.000399763 0 m N cfq3805 sl_used=1 disp=1 charge=1 iops=0 sect=8 8,16 0 0 0.000400227 0 m N cfq3805 del_from_rr 8,16 0 0 0.000400882 0 m N cfq3805 put_queue See, there are 19 lines while I only need 2. I don't think it is appropriate for a user. So this patch will disable any messages if the BLK_TC_NOTIFY isn't set. Now the output for the same command will look like: 8,16 0 1 0.000000000 4908 D R 114759 + 8 [dd] 8,16 0 2 0.000146827 0 C R 114759 + 8 [0] Yes, it is what I want to see. Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-10block: ensure that completion error gets properly tracedJens Axboe
We normally just use the BIO_UPTODATE flag to signal 0/-EIO. If we have more information available, we should pass that along to the trace output. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-07blktrace: add missing probe argument to block_bio_completeMathieu Desnoyers
blktrace.c block bio complete callback needs to gain a new argument to reflect the newly added "error" tracepoint argument. This is needed to match the new block_bio_complete TRACE_EVENT as of commit de983a7bfcb7c020901ca6e2314cf55a4207ab5a. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> CC: Jeff Moyer <jmoyer@redhat.com> CC: Steven Rostedt <rostedt@goodmis.org> CC: Frederic Weisbecker <fweisbec@gmail.com> CC: Ingo Molnar <mingo@elte.hu> CC: Thomas Gleixner <tglx@linutronix.de> CC: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-16block: Rename "block_remap" tracepoint to "block_bio_remap" to clarify the ↵Mike Snitzer
event. Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10block: remove REQ_HARDBARRIERChristoph Hellwig
REQ_HARDBARRIER is dead now, so remove the leftovers. What's left at this point is: - various checks inside the block layer. - sanity checks in bio based drivers. - now unused bio_empty_barrier helper. - Xen blockfront use of BLKIF_OP_WRITE_BARRIER - it's dead for a while, but Xen really needs to sort out it's barrier situaton. - setting of ordered tags in uas - dead code copied from old scsi drivers. - scsi different retry for barriers - it's dead and should have been removed when flushes were converted to FS requests. - blktrace handling of barriers - removed. Someone who knows blktrace better should add support for REQ_FLUSH and REQ_FUA, though. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-22Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bklLinus Torvalds
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: vfs: make no_llseek the default vfs: don't use BKL in default_llseek llseek: automatically add .llseek fop libfs: use generic_file_llseek for simple_attr mac80211: disallow seeks in minstrel debug code lirc: make chardev nonseekable viotape: use noop_llseek raw: use explicit llseek file operations ibmasmfs: use generic_file_llseek spufs: use llseek in all file operations arm/omap: use generic_file_llseek in iommu_debug lkdtm: use generic_file_llseek in debugfs net/wireless: use generic_file_llseek in debugfs drm: use noop_llseek
2010-10-19blktrace: remove the big kernel lockArnd Bergmann
According to Jens, this code does not need the BKL at all, it is sufficiently serialized by bd_mutex. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Jens Axboe <jaxboe@fusionio.com> Cc: Steven Rostedt <rostedt@goodmis.org>
2010-10-15llseek: automatically add .llseek fopArnd Bergmann
All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-12block: add secure discardAdrian Hunter
Secure discard is the same as discard except that all copies of the discarded sectors (perhaps created by garbage collection) must also be erased. Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com> Acked-by: Jens Axboe <axboe@kernel.dk> Cc: Kyungmin Park <kmpark@infradead.org> Cc: Madhusudhan Chikkature <madhu.cr@ti.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Ben Gardiner <bengardiner@nanometrics.ca> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-07block: push BKL into blktrace ioctlsArnd Bergmann
The blktrace driver currently needs the BKL, but we should not need to take that in the block layer, so just push it down into the driver itself. It is quite likely that the BKL is not actually required in blktrace code and could be removed in a follow-on patch. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07block: unify flags for struct bio and struct requestChristoph Hellwig
Remove the current bio flags and reuse the request flags for the bio, too. This allows to more easily trace the type of I/O from the filesystem down to the block driver. There were two flags in the bio that were missing in the requests: BIO_RW_UNPLUG and BIO_RW_AHEAD. Also I've renamed two request flags that had a superflous RW in them. Note that the flags are in bio.h despite having the REQ_ name - as blkdev.h includes bio.h that is the only way to go for now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07block: remove wrappers for request type/flagsChristoph Hellwig
Remove all the trivial wrappers for the cmd_type and cmd_flags fields in struct requests. This allows much easier grepping for different request types instead of unwinding through macros. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-05-31blktrace: Fix new kernel-doc warningsRandy Dunlap
Fix blktrace.c kernel-doc warnings: Warning(kernel/trace/blktrace.c:858): No description found for parameter 'ignore' Warning(kernel/trace/blktrace.c:890): No description found for parameter 'ignore' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20100529114507.c466fc1e.randy.dunlap@oracle.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-14tracing: Allow events to share their print functionsSteven Rostedt
Multiple events may use the same method to print their data. Instead of having all events have a pointer to their print funtions, the trace_event structure now points to a trace_event_functions structure that will hold the way to print ouf the event. The event itself is now passed to the print function to let the print function know what kind of event it should print. This opens the door to consolidating the way several events print their output. text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4900382 1048964 861512 6810858 67ecea vmlinux.init 4900446 1049028 861512 6810986 67ed6a vmlinux.preprint This change slightly increases the size but is needed for the next change. v3: Fix the branch tracer events to handle this change. v2: Fix the new function graph tracer event calls to handle this change. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-05-14tracing: Let tracepoints have data passed to tracepoint callbacksSteven Rostedt
This patch adds data to be passed to tracepoint callbacks. The created functions from DECLARE_TRACE() now need a mandatory data parameter. For example: DECLARE_TRACE(mytracepoint, int value, value) Will create the register function: int register_trace_mytracepoint((void(*)(void *data, int value))probe, void *data); As the first argument, all callbacks (probes) must take a (void *data) parameter. So a callback for the above tracepoint will look like: void myprobe(void *data, int value) { } The callback may choose to ignore the data parameter. This change allows callbacks to register a private data pointer along with the function probe. void mycallback(void *data, int value); register_trace_mytracepoint(mycallback, mydata); Then the mycallback() will receive the "mydata" as the first parameter before the args. A more detailed example: DECLARE_TRACE(mytracepoint, TP_PROTO(int status), TP_ARGS(status)); /* In the C file */ DEFINE_TRACE(mytracepoint, TP_PROTO(int status), TP_ARGS(status)); [...] trace_mytracepoint(status); /* In a file registering this tracepoint */ int my_callback(void *data, int status) { struct my_struct my_data = data; [...] } [...] my_data = kmalloc(sizeof(*my_data), GFP_KERNEL); init_my_data(my_data); register_trace_mytracepoint(my_callback, my_data); The same callback can also be registered to the same tracepoint as long as the data registered is different. Note, the data must also be used to unregister the callback: unregister_trace_mytracepoint(my_callback, my_data); Because of the data parameter, tracepoints declared this way can not have no args. That is: DECLARE_TRACE(mytracepoint, TP_PROTO(void), TP_ARGS()); will cause an error. If no arguments are needed, a new macro can be used instead: DECLARE_TRACE_NOARGS(mytracepoint); Since there are no arguments, the proto and args fields are left out. This is part of a series to make the tracepoint footprint smaller: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint Again, this patch also increases the size of the kernel, but lays the ground work for decreasing it. v5: Fixed net/core/drop_monitor.c to handle these updates. v4: Moved the DECLARE_TRACE() DECLARE_TRACE_NOARGS out of the #ifdef CONFIG_TRACE_POINTS, since the two are the same in both cases. The __DECLARE_TRACE() is what changes. Thanks to Frederic Weisbecker for pointing this out. v3: Made all register_* functions require data to be passed and all callbacks to take a void * parameter as its first argument. This makes the calling functions comply with C standards. Also added more comments to the modifications of DECLARE_TRACE(). v2: Made the DECLARE_TRACE() have the ability to pass arguments and added a new DECLARE_TRACE_NOARGS() for tracepoints that do not need any arguments. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-02-28blktrace: perform cleanup after setup errorDmitry Monakhov
Currently even if BLKTRACESETUP ioctl has failed user must call BLKTRACETEARDOWN to be shure what all staff was cleaned, which is contr-intuitive. Let's setup ioctl make necessery cleanup by it self. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-01Add a tracepoint for block request remappingJun'ichi Nomura
Since 2.6.31 now has request-based device-mapper, it's useful to have a tracepoint for request-remapping as well as bio-remapping. This patch adds a tracepoint for request-remapping, trace_block_rq_remap(). Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Cc: Alasdair G Kergon <agk@redhat.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-01Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfsZdenek Kabelac
Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs introduced in commit 1d54ad6da9192fed5dd3b60224d9f2dfea0dcd82. Release kobject also in case the request_fn is NULL. Problem was noticed via kmemleak backtrace when some sysfs entries were note properly destroyed during device removal: unreferenced object 0xffff88001aa76640 (size 80): comm "lvcreate", pid 2120, jiffies 4294885144 hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 f0 65 a7 1a 00 88 ff ff .........e...... 90 66 a7 1a 00 88 ff ff 86 1d 53 81 ff ff ff ff .f........S..... backtrace: [<ffffffff813f9cc6>] kmemleak_alloc+0x26/0x60 [<ffffffff8111d693>] kmem_cache_alloc+0x133/0x1c0 [<ffffffff81195891>] sysfs_new_dirent+0x41/0x120 [<ffffffff81194b0c>] sysfs_add_file_mode+0x3c/0xb0 [<ffffffff81197c81>] internal_create_group+0xc1/0x1a0 [<ffffffff81197d93>] sysfs_create_group+0x13/0x20 [<ffffffff810d8004>] blk_trace_init_sysfs+0x14/0x20 [<ffffffff8123f45c>] blk_register_queue+0x3c/0xf0 [<ffffffff812447e4>] add_disk+0x94/0x160 [<ffffffffa00d8b08>] dm_create+0x598/0x6e0 [dm_mod] [<ffffffffa00de951>] dev_create+0x51/0x350 [dm_mod] [<ffffffffa00de823>] ctl_ioctl+0x1a3/0x240 [dm_mod] [<ffffffffa00de8f2>] dm_compat_ctl_ioctl+0x12/0x20 [dm_mod] [<ffffffff81177bfd>] compat_sys_ioctl+0xcd/0x4f0 [<ffffffff81036ed8>] sysenter_dispatch+0x7/0x2c [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: Zdenek Kabelac <zkabelac@redhat.com> Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-06Merge commit 'v2.6.31-rc9' into tracing/coreIngo Molnar
Merge reason: move from -rc5 to -rc9. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04tracing: pass around ring buffer instead of tracerSteven Rostedt
The latency tracers (irqsoff and wakeup) can swap trace buffers on the fly. If an event is happening and has reserved data on one of the buffers, and the latency tracer swaps the global buffer with the max buffer, the result is that the event may commit the data to the wrong buffer. This patch changes the API to the trace recording to be recieve the buffer that was used to reserve a commit. Then this buffer can be passed in to the commit. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-12Remove double removal of blktrace directoryAlan D. Brunelle
commit fd51d251e4cdb21f68e9dbc4336514d64a105a79 Author: Stefan Raspl <raspl@linux.vnet.ibm.com> Date: Tue May 19 09:59:08 2009 +0200 blktrace: remove debugfs entries on bad path added in an explicit invocation of debugfs_remove for bt->dir, in blk_remove_buf_file_callback we are also getting the directory removed. On occasion I am seeing memory corruption that I have bisected down to this commit. [The testing involves a (long) series of I/O benchmarks with blktrace invoked around the actual runs.] I believe that this committed patch is correct, but the problem actually lies in the code in blk_remove_buf_file_callback. With this patch I am able to consistently get complete runs whereas previously I could not get a single run to complete. The first part of the patch simply moves the debugfs_remove below the relay_close: the relay_close call will remove files under bt->dir, and so we should not remove the directory until all the files we created have been removed. (Note: This is not sufficient to fix the problem - the file system code has ref counts on the directoy, so our invocation does not cause the directory to actually be removed. Nonetheless, we should not rely upon that feature.) Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-07-12headers: smp_lock.h reduxAlexey Dobriyan
* Remove smp_lock.h from files which don't need it (including some headers!) * Add smp_lock.h to files which do need it * Make smp_lock.h include conditional in hardirq.h It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT This will make hardirq.h inclusion cheaper for every PREEMPT=n config (which includes allmodconfig/allyesconfig, BTW) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits) block: add request clone interface (v2) floppy: fix hibernation ramdisk: remove long-deprecated "ramdisk=" boot-time parameter fs/bio.c: add missing __user annotation block: prevent possible io_context->refcount overflow Add serial number support for virtio_blk, V4a block: Add missing bounce_pfn stacking and fix comments Revert "block: Fix bounce limit setting in DM" cciss: decode unit attention in SCSI error handling code cciss: Remove no longer needed sendcmd reject processing code cciss: change SCSI error handling routines to work with interrupts enabled. cciss: separate error processing and command retrying code in sendcmd_withirq_core() cciss: factor out fix target status processing code from sendcmd functions cciss: simplify interface of sendcmd() and sendcmd_withirq() cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code cciss: Use schedule_timeout_uninterruptible in SCSI error handling code block: needs to set the residual length of a bidi request Revert "block: implement blkdev_readpages" block: Fix bounce limit setting in DM Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt ... Manually fix conflicts with tracing updates in: block/blk-sysfs.c drivers/ide/ide-atapi.c drivers/ide/ide-cd.c drivers/ide/ide-floppy.c drivers/ide/ide-tape.c include/trace/events/block.h kernel/trace/blktrace.c
2009-06-09tracing/events: convert block trace points to TRACE_EVENT()Li Zefan
TRACE_EVENT is a more generic way to define tracepoints. Doing so adds these new capabilities to this tracepoint: - zero-copy and per-cpu splice() tracing - binary tracing without printf overhead - structured logging records exposed under /debug/tracing/events - trace events embedded in function tracer output and other plugins - user-defined, per tracepoint filter expressions ... Cons: - no dev_t info for the output of plug, unplug_timer and unplug_io events. no dev_t info for getrq and sleeprq events if bio == NULL. no dev_t info for rq_abort,...,rq_requeue events if rq->rq_disk == NULL. This is mainly because we can't get the deivce from a request queue. But this may change in the future. - A packet command is converted to a string in TP_assign, not TP_print. While blktrace do the convertion just before output. Since pc requests should be rather rare, this is not a big issue. - In blktrace, an event can have 2 different print formats, but a TRACE_EVENT has a unique format, which means we have some unused data in a trace entry. The overhead is minimized by using __dynamic_array() instead of __array(). I've benchmarked the ioctl blktrace vs the splice based TRACE_EVENT tracing: dd dd + ioctl blktrace dd + TRACE_EVENT (splice) 1 7.36s, 42.7 MB/s 7.50s, 42.0 MB/s 7.41s, 42.5 MB/s 2 7.43s, 42.3 MB/s 7.48s, 42.1 MB/s 7.43s, 42.4 MB/s 3 7.38s, 42.6 MB/s 7.45s, 42.2 MB/s 7.41s, 42.5 MB/s So the overhead of tracing is very small, and no regression when using those trace events vs blktrace. And the binary output of TRACE_EVENT is much smaller than blktrace: # ls -l -h -rw-r--r-- 1 root root 8.8M 06-09 13:24 sda.blktrace.0 -rw-r--r-- 1 root root 195K 06-09 13:24 sda.blktrace.1 -rw-r--r-- 1 root root 2.7M 06-09 13:25 trace_splice.out Following are some comparisons between TRACE_EVENT and blktrace: plug: kjournald-480 [000] 303.084981: block_plug: [kjournald] kjournald-480 [000] 303.084981: 8,0 P N [kjournald] unplug_io: kblockd/0-118 [000] 300.052973: block_unplug_io: [kblockd/0] 1 kblockd/0-118 [000] 300.052974: 8,0 U N [kblockd/0] 1 remap: kjournald-480 [000] 303.085042: block_remap: 8,0 W 102736992 + 8 <- (8,8) 33384 kjournald-480 [000] 303.085043: 8,0 A W 102736992 + 8 <- (8,8) 33384 bio_backmerge: kjournald-480 [000] 303.085086: block_bio_backmerge: 8,0 W 102737032 + 8 [kjournald] kjournald-480 [000] 303.085086: 8,0 M W 102737032 + 8 [kjournald] getrq: kjournald-480 [000] 303.084974: block_getrq: 8,0 W 102736984 + 8 [kjournald] kjournald-480 [000] 303.084975: 8,0 G W 102736984 + 8 [kjournald] bash-2066 [001] 1072.953770: 8,0 G N [bash] bash-2066 [001] 1072.953773: block_getrq: 0,0 N 0 + 0 [bash] rq_complete: konsole-2065 [001] 300.053184: block_rq_complete: 8,0 W () 103669040 + 16 [0] konsole-2065 [001] 300.053191: 8,0 C W 103669040 + 16 [0] ksoftirqd/1-7 [001] 1072.953811: 8,0 C N (5a 00 08 00 00 00 00 00 24 00) [0] ksoftirqd/1-7 [001] 1072.953813: block_rq_complete: 0,0 N (5a 00 08 00 00 00 00 00 24 00) 0 + 0 [0] rq_insert: kjournald-480 [000] 303.084985: block_rq_insert: 8,0 W 0 () 102736984 + 8 [kjournald] kjournald-480 [000] 303.084986: 8,0 I W 102736984 + 8 [kjournald] Changelog from v2 -> v3: - use the newly introduced __dynamic_array(). Changelog from v1 -> v2: - use __string() instead of __array() to minimize the memory required to store hex dump of rq->cmd(). - support large pc requests. - add missing blk_fill_rwbs_rq() in block_rq_requeue TRACE_EVENT. - some cleanups. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4A2DF669.5070905@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-05-19blktrace: remove debugfs entries on bad pathStefan Raspl
debugfs directory entries for devices are not removed on some of the failure pathes in do_blk_trace_setup(). One way to reproduce is to start blktrace on multiple devices with insufficient Vmalloc space: Devices will fail with a message like this: BLKTRACESETUP(2) /dev/sdu failed: 5/Input/output error If so, the respective entries in debugfs (e.g. /sys/kernel/debug/block/sdu) will remain and subsequent attempts to start blktrace on the respective devices will not succeed due to existing directories. [ Impact: fix /debug/tracing file cleanup corner case ] Signed-off-by: Stefan Raspl <stefan.raspl@linux.vnet.ibm.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com LKML-Reference: <4A1266CC.5040801@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-11blktrace: pdu_buf of pc events should be unsignedLi Zefan
I got this: 8,0 1 305.417782332 2037 I R 32 (ffffff9e 10 00 ...) [bash] It should be: 8,0 1 305.417782332 2037 I R 32 (9e 10 00 ...) [bash] [ Impact: fix output of pc events ] Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4A07C6B3.9080802@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-11block: drop request->hard_* and *nr_sectorsTejun Heo
struct request has had a few different ways to represent some properties of a request. ->hard_* represent block layer's view of the request progress (completion cursor) and the ones without the prefix are supposed to represent the issue cursor and allowed to be updated as necessary by the low level drivers. The thing is that as block layer supports partial completion, the two cursors really aren't necessary and only cause confusion. In addition, manual management of request detail from low level drivers is cumbersome and error-prone at the very least. Another interesting duplicate fields are rq->[hard_]nr_sectors and rq->{hard_cur|current}_nr_sectors against rq->data_len and rq->bio->bi_size. This is more convoluted than the hard_ case. rq->[hard_]nr_sectors are initialized for requests with bio but blk_rq_bytes() uses it only for !pc requests. rq->data_len is initialized for all request but blk_rq_bytes() uses it only for pc requests. This causes good amount of confusion throughout block layer and its drivers and determining the request length has been a bit of black magic which may or may not work depending on circumstances and what the specific LLD is actually doing. rq->{hard_cur|current}_nr_sectors represent the number of sectors in the contiguous data area at the front. This is mainly used by drivers which transfers data by walking request segment-by-segment. This value always equals rq->bio->bi_size >> 9. However, data length for pc requests may not be multiple of 512 bytes and using this field becomes a bit confusing. In general, having multiple fields to represent the same property leads only to confusion and subtle bugs. With recent block low level driver cleanups, no driver is accessing or manipulating these duplicate fields directly. Drop all the duplicates. Now rq->sector means the current sector, rq->data_len the current total length and rq->bio->bi_size the current segment length. Everything else is defined in terms of these three and available only through accessors. * blk_recalc_rq_sectors() is collapsed into blk_update_request() and now handles pc and fs requests equally other than rq->sector update. This means that now pc requests can use partial completion too (no in-kernel user yet tho). * bio_cur_sectors() is replaced with bio_cur_bytes() as block layer now uses byte count as the primary data length. * blk_rq_pos() is now guranteed to be always correct. In-block users converted. * blk_rq_bytes() is now guaranteed to be always valid as is blk_rq_sectors(). In-block users converted. * blk_rq_sectors() is now guaranteed to equal blk_rq_bytes() >> 9. More convenient one is used. * blk_rq_bytes() and blk_rq_cur_bytes() are now inlined and take const pointer to request. [ Impact: API cleanup, single way to represent one property of a request ] Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11block: implement blk_rq_pos/[cur_]sectors() and convert obvious onesTejun Heo
Implement accessors - blk_rq_pos(), blk_rq_sectors() and blk_rq_cur_sectors() which return rq->hard_sector, rq->hard_nr_sectors and rq->hard_cur_sectors respectively and convert direct references of the said fields to the accessors. This is in preparation of request data length handling cleanup. Geert : suggested adding const to struct request * parameter to accessors Sergei : spotted error in patch description [ Impact: cleanup ] Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Grant Likely <grant.likely@secretlab.ca> Ackec-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Cc: Borislav Petkov <petkovbb@googlemail.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-06blktrace: from-sector redundant in trace_block_remapAlan D. Brunelle
Remove redundant from-sector parameter: it's /always/ the bio's sector passed in. [ Impact: cleanup ] Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com> Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <49FF517C.7000503@hp.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>