- 03 Mar, 2017 1 commit
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Steven Rostedt (VMware) authored
On boot up, if the kernel command line sets a graph funtion with the kernel command line options "ftrace_graph_filter" or "ftrace_graph_notrace" then it updates the corresponding function graph hash, ftrace_graph_hash or ftrace_graph_notrace_hash respectively. Unfortunately, at boot up, these variables are pointers to the "EMPTY_HASH" which is a constant used as a placeholder when a hash has no entities. The problem was that the comand line version to set the hashes updated the actual EMPTY_HASH instead of creating a new hash for the function graph. This broke the EMPTY_HASH because not only did it modify a constant (not sure how that was allowed to happen, except maybe because it was done at early boot, const variables were still mutable), but it made the filters have functions listed in them when they were actually empty. The kernel command line function needs to allocate a new hash for the function graph filters and assign the necessary variables to that new hash instead. Link: http://lkml.kernel.org/r/1488420091.7212.17.camel@linux.intel.com Cc: Namhyung Kim <namhyung@kernel.org> Fixes: b9b0c831 ("ftrace: Convert graph filter to use hash tables") Reported-by:
Todd Brandt <todd.e.brandt@linux.intel.com> Tested-by:
Todd Brandt <todd.e.brandt@linux.intel.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 27 Feb, 2017 1 commit
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Chunyu Hu authored
There is no function 'ftrace_ops_recurs_func' existing in the current code, it was renamed to ftrace_ops_assist_func() in commit c68c0fa2 ("ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too"). Update the comment to the correct function name. Link: http://lkml.kernel.org/r/1487723366-14463-1-git-send-email-chuhu@redhat.comSigned-off-by:
Chunyu Hu <chuhu@redhat.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 17 Feb, 2017 1 commit
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Joel Fernandes authored
The comment about ring buffer's organization is outdated and the code sits elsewhere, remove the comment. Link: http://lkml.kernel.org/r/20170217041058.23904-1-joelaf@google.com Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by:
Joel Fernandes <joelaf@google.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 15 Feb, 2017 8 commits
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Masami Hiramatsu authored
Since tracing/*probe_events will accept a probe definition up to 4096 - 2 ('\n' and '\0') bytes, it must show 4094 instead of 4096 in warning message. Note that there is one possible case of exceed 4094. If user prepare 4096 bytes null-terminated string and syscall write it with the count == 4095, then it can be accepted. However, if user puts a '\n' after that, it must rejected. So IMHO, the warning message should indicate shorter one, since it is safer. Link: http://lkml.kernel.org/r/148673290462.2579.7966778294009665632.stgit@devboxSigned-off-by:
Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Wei Yongjun authored
In case of error, the function kthread_run() returns ERR_PTR() and never returns NULL. The NULL test in the return value check should be replaced with IS_ERR(). Link: http://lkml.kernel.org/r/20170112135502.28556-1-weiyj.lk@gmail.com Cc: stable@vger.kernel.org Fixes: 81dc9f0e ("tracing: Add tracepoint benchmark tracepoint") Signed-off-by:
Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Arnd Bergmann authored
We get a lot of harmless warnings about this header file at W=1 level because of an unusual function declaration: kernel/trace/trace.h:766:1: error: 'inline' is not at beginning of declaration [-Werror=old-style-declaration] This moves the inline statement where it normally belongs, avoiding the warning. Link: http://lkml.kernel.org/r/20170123122521.3389010-1-arnd@arndb.de Fixes: 4046bf02 ("ftrace: Expose ftrace_hash_empty and ftrace_lookup_ip") Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Jason Baron authored
The static_key->next field goes mostly unused. The field is used for associating module uses with a static key. Most uses of struct static_key define a static key in the core kernel and make use of it entirely within the core kernel, or define the static key in a module and make use of it only from within that module. In fact, of the ~3,000 static keys defined, I found only about 5 or so that did not fit this pattern. Thus, we can remove the static_key->next field entirely and overload the static_key->entries field. That is, when all the static_key uses are contained within the same module, static_key->entries continues to point to those uses. However, if the static_key uses are not contained within the module where the static_key is defined, then we allocate a struct static_key_mod, store a pointer to the uses within that struct static_key_mod, and have the static key point at the static_key_mod. This does incur some extra memory usage when a static_key is used in a module that does not define it, but since there are only a handful of such cases there is a net savings. In order to identify if the static_key->entries pointer contains a struct static_key_mod or a struct jump_entry pointer, bit 1 of static_key->entries is set to 1 if it points to a struct static_key_mod and is 0 if it points to a struct jump_entry. We were already using bit 0 in a similar way to store the initial value of the static_key. This does mean that allocations of struct static_key_mod and that the struct jump_entry tables need to be at least 4-byte aligned in memory. As far as I can tell all arches meet this criteria. For my .config, the patch increased the text by 778 bytes, but reduced the data + bss size by 14912, for a net savings of 14,134 bytes. text data bss dec hex filename 8092427 5016512 790528 13899467 d416cb vmlinux.pre 8093205 5001600 790528 13885333 d3df95 vmlinux.post Link: http://lkml.kernel.org/r/1486154544-4321-1-git-send-email-jbaron@akamai.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by:
Jason Baron <jbaron@akamai.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Masami Hiramatsu authored
Show "trace_probe:", "trace_kprobe:" and "trace_uprobe:" headers for each warning/error/info message. This will help people to notice that kprobe/uprobe events caused those messages. Link: http://lkml.kernel.org/r/148646647813.24658.16705315294927615333.stgit@devboxSigned-off-by:
Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Luiz Capitulino authored
The ftrace hwlat does support a cpumask. Link: http://lkml.kernel.org/r/20170213122517.6e211955@redhat.comSigned-off-by:
Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Thomas Gleixner authored
The timer flags in the timer_start trace event contain lots of useful information, but the meaning is not clear in the trace output. Making tools rely on the bit positions is bad as they might change over time. Decode the flags in the print out. Tools can retrieve the bits and their meaning from the trace format file. Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1702101639290.4036@nanosRequested-by:
Arjan van de Ven <arjan@linux.intel.com> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
The code in traceprobe_probes_write() reads up to 4096 bytes from userpace for each line. If userspace passes in several lines to execute, the code will do a large read for each line, even though, it is highly likely that the first read from userspace received all of the lines at once. I changed the logic to do a single read from userspace, and to only read from userspace again if not all of the read from userspace made it in. I tested this by adding printk()s and writing files that would test -1, ==, and +1 the buffer size, to make sure that there's no overflows and that if a single line is written with +1 the buffer size, that it fails properly. Link: http://lkml.kernel.org/r/20170209180458.5c829ab2@gandalf.local.homeAcked-by:
Masami Hiramatsu <mhiramat@kernel.org> Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 10 Feb, 2017 1 commit
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Steven Rostedt (VMware) authored
The GLOB operation "~" should be able to work with the COMM filter key in order to trace programs with a glob. For example echo 'COMM ~ "systemd*"' > events/syscalls/filter Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 03 Feb, 2017 8 commits
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Steven Rostedt (VMware) authored
Currently, only one function can be written to set_graph_function and set_graph_notrace. The last function in the list will have saved, even though other functions will be added then removed. Change the behavior to be the same as set_ftrace_function as to allow multiple functions to be written. If any one fails, none of them will be added. The addition of the functions are done at the end when the file is closed. Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
The hashs ftrace_graph_hash and ftrace_graph_notrace_hash are modified within the graph_lock being held. Holding a pointer to them and passing them along can lead to a use of a stale pointer (fgd->hash). Move assigning the pointer and its use to within the holding of the lock. Note, it's an rcu_sched protected data, and other instances of referencing them are done with preemption disabled. But the file manipuation code must be protected by the lock. The fgd->hash pointer is set to NULL when the lock is being released. Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
trace_parser_put() simply frees the allocated parser buffer. But it does not reset the pointer that was freed. This means that if trace_parser_put() is called on the same parser more than once, it will corrupt the allocation system. Setting parser->buffer to NULL after free allows it to be called more than once without any ill effect. Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
Since reading the set_graph_functions uses seq functions, which sets the file->private_data pointer to a seq_file descriptor. On writes the ftrace_graph_data descriptor is set to file->private_data. But if the file is opened for RDWR, the ftrace_graph_write() will incorrectly use the file->private_data descriptor instead of ((struct seq_file *)file->private_data)->private pointer, and this can crash the kernel. Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
fgd->hash is saved and then freed, but is never reset to either ftrace_graph_hash nor ftrace_graph_notrace_hash. But if multiple writes are performed, then the freed hash could be accessed again. # cd /sys/kernel/debug/tracing # head -1000 available_filter_functions > /tmp/funcs # cat /tmp/funcs > set_graph_function Causes: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC Modules linked in: [...] CPU: 2 PID: 1337 Comm: cat Not tainted 4.10.0-rc2-test-00010-g6b052e9 #32 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012 task: ffff880113a12200 task.stack: ffffc90001940000 RIP: 0010:free_ftrace_hash+0x7c/0x160 RSP: 0018:ffffc90001943db0 EFLAGS: 00010246 RAX: 6b6b6b6b6b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: 6b6b6b6b6b6b6b6b RDX: 0000000000000002 RSI: 0000000000000001 RDI: ffff8800ce1e1d40 RBP: ffff8800ce1e1d50 R08: 0000000000000000 R09: 0000000000006400 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8800ce1e1d40 R14: 0000000000004000 R15: 0000000000000001 FS: 00007f9408a07740(0000) GS:ffff88011e500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000aee1f0 CR3: 0000000116bb4000 CR4: 00000000001406e0 Call Trace: ? ftrace_graph_write+0x150/0x190 ? __vfs_write+0x1f6/0x210 ? __audit_syscall_entry+0x17f/0x200 ? rw_verify_area+0xdb/0x210 ? _cond_resched+0x2b/0x50 ? __sb_start_write+0xb4/0x130 ? vfs_write+0x1c8/0x330 ? SyS_write+0x62/0xf0 ? do_syscall_64+0xa3/0x1b0 ? entry_SYSCALL64_slow_path+0x25/0x25 Code: 01 48 85 db 0f 84 92 00 00 00 b8 01 00 00 00 d3 e0 85 c0 7e 3f 83 e8 01 48 8d 6f 10 45 31 e4 4c 8d 34 c5 08 00 00 00 49 8b 45 08 <4a> 8b 34 20 48 85 f6 74 13 48 8b 1e 48 89 ef e8 20 fa ff ff 48 RIP: free_ftrace_hash+0x7c/0x160 RSP: ffffc90001943db0 ---[ end trace 999b48216bf4b393 ]--- Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
When the set_graph_function or set_graph_notrace contains no records, a banner is displayed of either "#### all functions enabled ####" or "#### all functions disabled ####" respectively. To tell the seq operations to do this, (void *)1 is passed as a return value. Instead of using a hardcoded meaningless variable, define it as a macro. Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
This is a micro-optimization, but as it has to deal with a fast path of the function tracer, these optimizations can be noticed. The ftrace_lookup_ip() returns true if the given ip is found in the hash. If it's not found or the hash is NULL, it returns false. But there's some cases that a NULL hash is a true, and the ftrace_hash_empty() is tested before calling ftrace_lookup_ip() in those cases. But as ftrace_lookup_ip() tests that first, that adds a few extra unneeded instructions in those cases. A new static "always_inlined" function is created that does not perform the hash empty test. This most only be used by callers that do the check first anyway, as an empty or NULL hash could cause a crash if a lookup is performed on it. Also add kernel doc for the ftrace_lookup_ip() main function. Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
Replace the couple of use cases that has small logic to produce the ftrace function key id with a helper function. No need for duplicate code. Acked-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 20 Jan, 2017 3 commits
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Namhyung Kim authored
Use ftrace_hash instead of a static array of a fixed size. This is useful when a graph filter pattern matches to a large number of functions. Now hash lookup is done with preemption disabled to protect from the hash being changed/freed. Link: http://lkml.kernel.org/r/20170120024447.26097-3-namhyung@kernel.orgSigned-off-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Namhyung Kim authored
It will be used when checking graph filter hashes later. Link: http://lkml.kernel.org/r/20170120024447.26097-2-namhyung@kernel.orgSigned-off-by:
Namhyung Kim <namhyung@kernel.org> [ Moved ftrace_hash dec and functions outside of FUNCTION_GRAPH define ] Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Namhyung Kim authored
The __ftrace_hash_move() is to allocates properly-sized hash and move entries in the src ftrace_hash. It will be used to set function graph filters which has nothing to do with the dyn_ftrace records. Link: http://lkml.kernel.org/r/20170120024447.26097-1-namhyung@kernel.orgSigned-off-by:
Namhyung Kim <namhyung@kernel.org> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 19 Jan, 2017 2 commits
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Steven Rostedt (VMware) authored
The unlikely/likely branch profiler now gets called even if the if statement is a constant (always goes in one direction without a compare). Add a value to denote this in the likely/unlikely tracer as well. Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
Now that constants are traced, it is useful to see the number of constants that are traced in the likely/unlikely profiler in order to know if they should be ignored or not. The likely/unlikely will display a number after the "correct" number if a "constant" count exists. Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 17 Jan, 2017 2 commits
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Steven Rostedt (VMware) authored
When running the likely/unlikely profiler, one of the results did not look accurate. It noted that the unlikely() in link_path_walk() was 100% incorrect. When I added a trace_printk() to see what was happening there, it became 80% correct! Looking deeper into what whas happening, I found that gcc split that if statement into two paths. One where the if statement became a constant, the other path a variable. The other path had the if statement always hit (making the unlikely there, always false), but since the #define unlikely() has: #define unlikely() (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 0)) Where constants are ignored by the branch profiler, the "constant" path made by the compiler was ignored, even though it was hit 80% of the time. By just passing the constant value to the __branch_check__() function and tracing it out of line (as always correct, as likely/unlikely isn't a factor for constants), then we get back the accurate readings of branches that were optimized by gcc causing part of the execution to become constant. Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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Kenny Yu authored
Previously, `create_trace_uprobe` found the *first* occurence of the ':' character when parsing `PATH:OFFSET` for a uprobe. However, if the path contains a ':' character, then the function would parse the path incorrectly. Even worse, if the path does not exist, the subsequent call to `kern_path()` would set `ret` to `ENOENT`, leading to very cryptic errno values in user space. The fix is to find the *last* occurence of ':'. How to repro:: The write fails with "No such file or directory", suggesting incorrectly that the `uprobe_events` file does not exist. $ mkdir testing && cd testing $ cp /bin/bash . $ cp /bin/bash ./bash:with:colon $ echo "p:uprobes/p__root_testing_bash_0x6 /root/testing/bash:0x6" > /sys/kernel/debug/tracing/uprobe_events # this works $ echo "p:uprobes/p__root_testing_bash_with_colon_0x6 /root/testing/bash:with:colon:0x6" >> /sys/kernel/debug/tracing/uprobe_events # this doesn't -bash: echo: write error: No such file or directory With the patch: $ echo "p:uprobes/p__root_testing_bash_0x6 /root/testing/bash:0x6" > /sys/kernel/debug/tracing/uprobe_events # this still works $ echo "p:uprobes/p__root_testing_bash_with_colon_0x6 /root/testing/bash:with:colon:0x6" >> /sys/kernel/debug/tracing/uprobe_events # this works now too! $ cat /sys/kernel/debug/tracing/uprobe_events p:uprobes/p__root_testing_bash_0x6 /root/testing/bash:0x0000000000000006 p:uprobes/p__root_testing_bash_with_colon_0x6 /root/testing/bash:with:colon:0x0000000000000006 Link: http://lkml.kernel.org/r/20170113165834.4081016-1-kennyyu@fb.comSigned-off-by:
Kenny Yu <kennyyu@fb.com> Reviewed-by:
Omar Sandoval <osandov@fb.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 01 Jan, 2017 2 commits
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimmLinus Torvalds authored
Pull DAX updates from Dan Williams: "The completion of Jan's DAX work for 4.10. As I mentioned in the libnvdimm-for-4.10 pull request, these are some final fixes for the DAX dirty-cacheline-tracking invalidation work that was merged through the -mm, ext4, and xfs trees in -rc1. These patches were prepared prior to the merge window, but we waited for 4.10-rc1 to have a stable merge base after all the prerequisites were merged. Quoting Jan on the overall changes in these patches: "So I'd like all these 6 patches to go for rc2. The first three patches fix invalidation of exceptional DAX entries (a bug which is there for a long time) - without these patches data loss can occur on power failure even though user called fsync(2). The other three patches change locking of DAX faults so that ->iomap_begin() is called in a more relaxed locking context and we are safe to start a transaction there for ext4" These have received a build success notification from the kbuild robot, and pass the latest libnvdimm unit tests. There have not been any -next releases since -rc1, so they have not appeared there" * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: ext4: Simplify DAX fault path dax: Call ->iomap_begin without entry lock during dax fault dax: Finish fault completely when loading holes dax: Avoid page invalidation races and unnecessary radix tree traversals mm: Invalidate DAX radix tree entries only if appropriate ext2: Return BH_New buffers for zeroed blocks
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- 30 Dec, 2016 2 commits
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git://git.lwn.net/linuxLinus Torvalds authored
Pull documentation fixes from Jonathan Corbet: "Two small fixes: - A merge error on my part broke the DocBook build. I've requisitioned one of tglx's frozen sharks for appropriate disciplinary action and resolved to be more careful about testing the DocBook stuff as long as it's still around. - Fix an error in unaligned-memory-access.txt" * tag 'docs-4.10-rc1-fix' of git://git.lwn.net/linux: Documentation/unaligned-memory-access.txt: fix incorrect comparison operator docs: Fix build failure
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git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds authored
Pull crypto fix from Herbert Xu: "This fixes a boot failure on some platforms when crypto self test is enabled along with the new acomp interface" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: testmgr - Use heap buffer for acomp test input
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- 29 Dec, 2016 2 commits
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Olof Johansson authored
mm/filemap.c: In function 'clear_bit_unlock_is_negative_byte': mm/filemap.c:933:9: error: too few arguments to function 'test_bit' return test_bit(PG_waiters); ^~~~~~~~ Fixes: b91e1302 ('mm: optimize PageWaiters bit use for unlock_page()') Signed-off-by:
Olof Johansson <olof@lixom.net> Brown-paper-bag-by:
Linus Torvalds <dummy@duh.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
In commit 62906027 ("mm: add PageWaiters indicating tasks are waiting for a page bit") Nick Piggin made our page locking no longer unconditionally touch the hashed page waitqueue, which not only helps performance in general, but is particularly helpful on NUMA machines where the hashed wait queues can bounce around a lot. However, the "clear lock bit atomically and then test the waiters bit" sequence turns out to be much more expensive than it needs to be, because you get a nasty stall when trying to access the same word that just got updated atomically. On architectures where locking is done with LL/SC, this would be trivial to fix with a new primitive that clears one bit and tests another atomically, but that ends up not working on x86, where the only atomic operations that return the result end up being cmpxchg and xadd. The atomic bit operations return the old value of the same bit we changed, not the value of an unrelated bit. On x86, we could put the lock bit in the high bit of the byte, and use "xadd" with that bit (where the overflow ends up not touching other bits), and look at the other bits of the result. However, an even simpler model is to just use a regular atomic "and" to clear the lock bit, and then the sign bit in eflags will indicate the resulting state of the unrelated bit #7. So by moving the PageWaiters bit up to bit #7, we can atomically clear the lock bit and test the waiters bit on x86 too. And architectures with LL/SC (which is all the usual RISC suspects), the particular bit doesn't matter, so they are fine with this approach too. This avoids the extra access to the same atomic word, and thus avoids the costly stall at page unlock time. The only downside is that the interface ends up being a bit odd and specialized: clear a bit in a byte, and test the sign bit. Nick doesn't love the resulting name of the new primitive, but I'd rather make the name be descriptive and very clear about the limitation imposed by trying to work across all relevant architectures than make it be some generic thing that doesn't make the odd semantics explicit. So this introduces the new architecture primitive clear_bit_unlock_is_negative_byte(); and adds the trivial implementation for x86. We have a generic non-optimized fallback (that just does a "clear_bit()"+"test_bit(7)" combination) which can be overridden by any architecture that can do better. According to Nick, Power has the same hickup x86 has, for example, but some other architectures may not even care. All these optimizations mean that my page locking stress-test (which is just executing a lot of small short-lived shell scripts: "make test" in the git source tree) no longer makes our page locking look horribly bad. Before all these optimizations, just the unlock_page() costs were just over 3% of all CPU overhead on "make test". After this, it's down to 0.66%, so just a quarter of the cost it used to be. (The difference on NUMA is bigger, but there this micro-optimization is likely less noticeable, since the big issue on NUMA was not the accesses to 'struct page', but the waitqueue accesses that were already removed by Nick's earlier commit). Acked-by:
Nick Piggin <npiggin@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Bob Peterson <rpeterso@redhat.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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- 28 Dec, 2016 2 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds authored
Pull crypto fix from Herbert Xu: "This fixes a hash corruption bug in the marvell driver" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: marvell - Copy IVDIG before launching partial DMA ahash requests
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) Various ipvlan fixes from Eric Dumazet and Mahesh Bandewar. The most important is to not assume the packet is RX just because the destination address matches that of the device. Such an assumption causes problems when an interface is put into loopback mode. 2) If we retry when creating a new tc entry (because we dropped the RTNL mutex in order to load a module, for example) we end up with -EAGAIN and then loop trying to replay the request. But we didn't reset some state when looping back to the top like this, and if another thread meanwhile inserted the same tc entry we were trying to, we re-link it creating an enless loop in the tc chain. Fix from Daniel Borkmann. 3) There are two different WRITE bits in the MDIO address register for the stmmac chip, depending upon the chip variant. Due to a bug we could set them both, fix from Hock Leong Kweh. 4) Fix mlx4 bug in XDP_TX handling, from Tariq Toukan. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: net: stmmac: fix incorrect bit set in gmac4 mdio addr register r8169: add support for RTL8168 series add-on card. net: xdp: remove unused bfp_warn_invalid_xdp_buffer() openvswitch: upcall: Fix vlan handling. ipv4: Namespaceify tcp_tw_reuse knob net: korina: Fix NAPI versus resources freeing net, sched: fix soft lockup in tc_classify net/mlx4_en: Fix user prio field in XDP forward tipc: don't send FIN message from connectionless socket ipvlan: fix multicast processing ipvlan: fix various issues in ipvlan_process_multicast()
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- 27 Dec, 2016 5 commits
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Cihangir Akturk authored
In the actual implementation ether_addr_equal function tests for equality to 0 when returning. It seems in commit 0d74c4 it is somehow overlooked to change this operator to reflect the actual function. Signed-off-by:
Cihangir Akturk <cakturk@gmail.com> Signed-off-by:
Jonathan Corbet <corbet@lwn.net>
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John Brooks authored
The 80211.tmpl DocBook file was removed in commit 819bf593 ("docs-rst: sphinxify 802.11 documentation"), but the 80211.xml target was re-added to the Makefile by commit 7ddedebb ("ALSA: doc: ReSTize writing-an-alsa-driver document"), leading to a failure when building the documentation: *** No rule to make target 'Documentation/DocBook/80211.xml', needed by 'Documentation/DocBook/80211.aux.xml'. cc: stable@vger.kernel.org Signed-off-by:
John Brooks <john@fastquake.com> Mea-culpa-by:
Jonathan Corbet <corbet@lwn.net> Signed-off-by:
Jonathan Corbet <corbet@lwn.net>
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Jonathan Corbet authored
Linux 4.10-rc1
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Kweh, Hock Leong authored
Fixing the gmac4 mdio write access to use MII_GMAC4_WRITE only instead of OR together with MII_WRITE. Signed-off-by:
Kweh, Hock Leong <hock.leong.kweh@intel.com> Acked-By:
Joao Pinto <jpinto@synopsys.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
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Chun-Hao Lin authored
This chip is the same as RTL8168, but its device id is 0x8161. Signed-off-by:
Chun-Hao Lin <hau@realtek.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
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