user/sven/linux.git/include/linux/cpumask.h, branch v4.4.265

cpumask: Make for_each_cpu_wrap() available on UP as well

2020-05-27T14:40:33Z

commit d207af2eab3f8668b95ad02b21930481c42806fd upstream. for_each_cpu_wrap() was originally added in the #else half of a large "#if NR_CPUS == 1" statement, but was omitted in the #if half. This patch adds the missing #if half to prevent compile errors when NR_CPUS is 1. Reported-by: kbuild test robot Signed-off-by: Michael Kelley Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kys@microsoft.com Cc: martin.petersen@oracle.com Cc: mikelley@microsoft.com Fixes: c743f0a5c50f ("sched/fair, cpumask: Export for_each_cpu_wrap()") Link: http://lkml.kernel.org/r/SN6PR1901MB2045F087F59450507D4FCC17CBF50@SN6PR1901MB2045.namprd19.prod.outlook.com Signed-off-by: Ingo Molnar Cc: Signed-off-by: Greg Kroah-Hartman

sched/fair, cpumask: Export for_each_cpu_wrap()

2020-05-27T14:40:27Z

[ Upstream commit c743f0a5c50f2fcbc628526279cfa24f3dabe182 ] More users for for_each_cpu_wrap() have appeared. Promote the construct to generic cpumask interface. The implementation is slightly modified to reduce arguments. Signed-off-by: Peter Zijlstra (Intel) Cc: Lauro Ramos Venancio Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: lwang@redhat.com Link: http://lkml.kernel.org/r/20170414122005.o35me2h5nowqkxbv@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar [dj: include only what's added to the cpumask interface, 4.4 doesn't have them in the scheduler] Signed-off-by: Daniel Jordan Signed-off-by: Sasha Levin

cpumask: Add helper cpumask_available()

2018-04-08T09:51:57Z

commit f7e30f01a9e221067bb4b579e3cfc25cd2617467 upstream. With CONFIG_CPUMASK_OFFSTACK=y cpumask_var_t is a struct cpumask pointer, otherwise a struct cpumask array with a single element. Some code dealing with cpumasks needs to validate that a cpumask_var_t is not a NULL pointer when CONFIG_CPUMASK_OFFSTACK=y. This is typically done by performing the check always, regardless of the underlying type of cpumask_var_t. This works in both cases, however clang raises a warning like this when CONFIG_CPUMASK_OFFSTACK=n: kernel/irq/manage.c:839:28: error: address of array 'desc->irq_common_data.affinity' will always evaluate to 'true' [-Werror,-Wpointer-bool-conversion] Add the inline helper cpumask_available() which only performs the pointer check if CONFIG_CPUMASK_OFFSTACK=y. Signed-off-by: Matthias Kaehlcke Cc: Grant Grundler Cc: Rusty Russell Cc: Greg Hackmann Cc: Michael Davidson Cc: Andrew Morton Link: http://lkml.kernel.org/r/20170412182030.83657-1-mka@chromium.org Signed-off-by: Thomas Gleixner Cc: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

cpumask: use nr_cpumask_bits for parsing functions

2017-02-14T23:22:51Z

commit 4d59b6ccf000862beed6fc0765d3209f98a8d8a2 upstream. Commit 513e3d2d11c9 ("cpumask: always use nr_cpu_ids in formatting and parsing functions") converted both cpumask printing and parsing functions to use nr_cpu_ids instead of nr_cpumask_bits. While this was okay for the printing functions as it just picked one of the two output formats that we were alternating between depending on a kernel config, doing the same for parsing wasn't okay. nr_cpumask_bits can be either nr_cpu_ids or NR_CPUS. We can always use nr_cpu_ids but that is a variable while NR_CPUS is a constant, so it can be more efficient to use NR_CPUS when we can get away with it. Converting the printing functions to nr_cpu_ids makes sense because it affects how the masks get presented to userspace and doesn't break anything; however, using nr_cpu_ids for parsing functions can incorrectly leave the higher bits uninitialized while reading in these masks from userland. As all testing and comparison functions use nr_cpumask_bits which can be larger than nr_cpu_ids, the parsed cpumasks can erroneously yield false negative results. This made the taskstats interface incorrectly return -EINVAL even when the inputs were correct. Fix it by restoring the parse functions to use nr_cpumask_bits instead of nr_cpu_ids. Link: http://lkml.kernel.org/r/20170206182442.GB31078@htj.duckdns.org Fixes: 513e3d2d11c9 ("cpumask: always use nr_cpu_ids in formatting and parsing functions") Signed-off-by: Tejun Heo Reported-by: Martin Steigerwald Debugged-by: Ben Hutchings Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

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