user/sven/linux.git/include/linux/cpumask.h, branch v4.4.27

cpumask_set_cpu_local_first => cpumask_local_spread, lament

2015-05-28T01:35:20Z

da91309e0a7e (cpumask: Utility function to set n'th cpu...) created a genuinely weird function. I never saw it before, it went through DaveM. (He only does this to make us other maintainers feel better about our own mistakes.) cpumask_set_cpu_local_first's purpose is say "I need to spread things across N online cpus, choose the ones on this numa node first"; you call it in a loop. It can fail. One of the two callers ignores this, the other aborts and fails the device open. It can fail in two ways: allocating the off-stack cpumask, or through a convoluted codepath which AFAICT can only occur if cpu_online_mask changes. Which shouldn't happen, because if cpu_online_mask can change while you call this, it could return a now-offline cpu anyway. It contains a nonsensical test "!cpumask_of_node(numa_node)". This was drawn to my attention by Geert, who said this causes a warning on Sparc. It sets a single bit in a cpumask instead of returning a cpu number, because that's what the callers want. It could be made more efficient by passing the previous cpu rather than an index, but that would be more invasive to the callers. Fixes: da91309e0a7e8966d916a74cce42ed170fde06bf Signed-off-by: Rusty Russell (then rebased) Tested-by: Amir Vadai Acked-by: Amir Vadai Acked-by: David S. Miller

cpumask: resurrect CPU_MASK_CPU0

2015-04-16T03:03:51Z

We removed it in 2f0f267ea072 (cpumask: remove deprecated functions.), but grep shows it still used by MIPS, and not unreasonably. Signed-off-by: Rusty Russell

linux/cpumask.h: add typechecking to cpumask_test_cpu

2015-03-31T03:25:31Z

The Subtlety (1) referred to vanished with 6ba2ef7baac2 ("cpumask: Move deprecated functions to end of header."). That used to mention some suboptimal code generation by a, by now, rather ancient gcc. With gcc 4.7, I don't see any change in the generated code by making it a static inline, so let's add type checking and get rid of the ghost reference. Signed-off-by: Rasmus Villemoes Signed-off-by: Rusty Russell

cpumask: only allocate nr_cpumask_bits.

2015-03-10T03:24:42Z

Now we'll find out the hard way if anyone has CPUMASK_OFFSTACK and is returning these or assigning them. Signed-off-by: Rusty Russell

cpumask: remove deprecated functions.

2015-03-10T03:24:41Z

Using these functions with offstack cpus is unsafe. They use all NR_CPUS bits, unstead of nr_cpumask_bits. In particular, lustre (in staging) used cpus_ and that caused a bug. Reported-by: Oleg Drokin Signed-off-by: Rusty Russell

CPU_MASK_ALL/CPU_MASK_NONE: remove from deprecated region.

2015-03-05T04:57:06Z

They're used to initialize various static fields, though static cpumasks should generally be avoided. Signed-off-by: Rusty Russell

bitmap, cpumask, nodemask: remove dedicated formatting functions

2015-02-14T05:21:39Z

Now that all bitmap formatting usages have been converted to '%*pb[l]', the separate formatting functions are unnecessary. The following functions are removed. * bitmap_scn[list]printf() * cpumask_scnprintf(), cpulist_scnprintf() * [__]nodemask_scnprintf(), [__]nodelist_scnprintf() * seq_bitmap[_list](), seq_cpumask[_list](), seq_nodemask[_list]() * seq_buf_bitmask() Signed-off-by: Tejun Heo Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

cpumask, nodemask: implement cpumask/nodemask_pr_args()

2015-02-14T05:21:36Z

printf family of functions can now format bitmaps using '%*pb[l]' and all cpumask and nodemask formatting will be converted to use it. To ease printing these masks with '%*pb[l]' which require two params - the number of bits and the actual bitmap, this patch implement cpumask_pr_args() and nodemask_pr_args() which can be used to provide arguments for '%*pb[l]' Signed-off-by: Tejun Heo Cc: Rusty Russell Cc: "David S. Miller" Cc: "James E.J. Bottomley" Cc: "John W. Linville" Cc: "Paul E. McKenney" Cc: Benjamin Herrenschmidt Cc: Chris Metcalf Cc: Chris Zankel Cc: Christoph Lameter Cc: Dmitry Torokhov Cc: Fenghua Yu Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Li Zefan Cc: Max Filippov Cc: Mike Travis Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Russell King Cc: Steffen Klassert Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Tony Luck Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

cpumask: always use nr_cpu_ids in formatting and parsing functions

2015-02-14T05:21:36Z

bitmap implements two variants of scnprintf functions to format a bitmap into a string and cpumask and nodemask wrap them to provide equivalent interfaces. The scnprintf family of functions require a string buffer as an output target which complicates code paths which just want to print out the mask through printk for informational or debug purposes as they have to worry about how large the buffer should be and whether it's too large to allocate on stack. Neither cpumask or nodemask provides a guildeline on how large the target buffer should be forcing users come up with their own solutions - some allocate an arbitrarily sized buffer which is small enough to allocate on stack but may be too short in corner cases, other come up with a custom upper limit calculation considering the output format, some allocate the buffer dynamically while one resorted to using lock to synchronize access to a static buffer. This is an artificial problem which is being solved repeatedly for no benefit. In a lot of cases, the output area already exists and can be targeted directly making the intermediate buffer unnecessary. This patchset teaches printf family of functions how to format bitmaps and replace the dedicated formatting functions with it. Pointer formatting is extended to cover bitmap formatting. It uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. For more details, please see 0002. This patch (of 31): Currently, the formatting and parsing functions in cpumask.h use nr_cpumask_bits like other cpumask functions; however, nr_cpumask_bits is either NR_CPUS or nr_cpu_ids depending on CONFIG_CPUMASK_OFFSTACK. This leads to inconsistent behaviors. With CONFIG_NR_CPUS=512 and !CONFIG_CPUMASK_OFFSTACK # cat /sys/devices/virtual/net/lo/queues/rx-0/rps_cpus 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000 # cat /proc/self/status | grep Cpus_allowed: Cpus_allowed: f With CONFIG_NR_CPUS=1024 and CONFIG_CPUMASK_OFFSTACK (fedora default) # cat /sys/devices/virtual/net/lo/queues/rx-0/rps_cpus 0 # cat /proc/self/status | grep Cpus_allowed: Cpus_allowed: f Note that /proc/self/status is always using nr_cpu_ids regardless of config. This is because seq cpumask formattings functions always use nr_cpu_ids. Given that the same output fields may switch between the two forms, converging on nr_cpu_ids always isn't too likely to surprise userland. This patch updates the formatting and parsing functions in cpumask.h to always use nr_cpu_ids. There's no point in dealing with CPUs which aren't even possible on the machine. Signed-off-by: Tejun Heo Cc: "David S. Miller" Cc: "James E.J. Bottomley" Cc: "John W. Linville" Cc: "Paul E. McKenney" Cc: Benjamin Herrenschmidt Cc: Chris Metcalf Cc: Chris Zankel Cc: Christoph Lameter Cc: Dmitry Torokhov Cc: Fenghua Yu Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Li Zefan Cc: Max Filippov Cc: Mike Travis Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Russell King Acked-by: Rusty Russell Cc: Steffen Klassert Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Tony Luck Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

linux/cpumask.h: update bitmap wrappers to take unsigned int

2015-02-13T02:54:14Z

Since the various bitmap_* functions now take an unsigned int as nbits parameter, it makes sense to also update the various wrappers, even though they're marked as obsolete. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds