talos-op-linux/lib/cpumask.c, branch v4.2.2

revert "cpumask: don't perform while loop in cpumask_next_and()"

2015-06-19T03:00:23+00:00

Revert commit 534b483a86e6 ("cpumask: don't perform while loop in cpumask_next_and()"). This was a minor optimization, but it puts a `struct cpumask' on the stack, which consumes too much stack space. Sergey Senozhatsky Reported-by: Peter Zijlstra Cc: Sergey Senozhatsky Cc: Tejun Heo Cc: "David S. Miller" Cc: Amir Vadai Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

cpumask_set_cpu_local_first => cpumask_local_spread, lament

2015-05-28T01:35:20+00:00

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

Merge tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2015-04-20T17:19:03+00:00

Pull final removal of deprecated cpus_* cpumask functions from Rusty Russell: "This is the final removal (after several years!) of the obsolete cpus_* functions, prompted by their mis-use in staging. With these function removed, all cpu functions should only iterate to nr_cpu_ids, so we finally only allocate that many bits when cpumasks are allocated offstack" * tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (25 commits) cpumask: remove __first_cpu / __next_cpu cpumask: resurrect CPU_MASK_CPU0 linux/cpumask.h: add typechecking to cpumask_test_cpu cpumask: only allocate nr_cpumask_bits. Fix weird uses of num_online_cpus(). cpumask: remove deprecated functions. mips: fix obsolete cpumask_of_cpu usage. x86: fix more deprecated cpu function usage. ia64: remove deprecated cpus_ usage. powerpc: fix deprecated CPU_MASK_CPU0 usage. CPU_MASK_ALL/CPU_MASK_NONE: remove from deprecated region. staging/lustre/o2iblnd: Don't use cpus_weight staging/lustre/libcfs: replace deprecated cpus_ calls with cpumask_ staging/lustre/ptlrpc: Do not use deprecated cpus_* functions blackfin: fix up obsolete cpu function usage. parisc: fix up obsolete cpu function usage. tile: fix up obsolete cpu function usage. arm64: fix up obsolete cpu function usage. mips: fix up obsolete cpu function usage. x86: fix up obsolete cpu function usage. ...

cpumask: remove __first_cpu / __next_cpu

2015-04-19T05:05:32+00:00

They were for use by the deprecated first_cpu() and next_cpu() wrappers, but sparc used them directly. They're now replaced by cpumask_first / cpumask_next. And __next_cpu_nr is completely obsolete. Signed-off-by: Rusty Russell Acked-by: David S. Miller

cpumask: don't perform while loop in cpumask_next_and()

2015-04-17T13:04:08+00:00

cpumask_next_and() is looking for cpumask_next() in src1 in a loop and tests if found cpu is also present in src2. remove that loop, perform cpumask_and() of src1 and src2 first and use that new mask to find cpumask_next(). Apart from removing while loop, ./bloat-o-meter on x86_64 shows add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8) function old new delta cpumask_next_and 62 54 -8 Signed-off-by: Sergey Senozhatsky Cc: Tejun Heo Cc: "David S. Miller" Cc: Amir Vadai Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

cpumask: only allocate nr_cpumask_bits.

2015-03-10T03:24:42+00:00

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

lib/cpumask: cpumask_set_cpu_local_first to use all cores when numa node is not defined

2014-07-03T01:29:23+00:00

When device is non numa aware (numa_node == -1), use all online cpu's. Signed-off-by: Amir Vadai Signed-off-by: David S. Miller

cpumask: Utility function to set n'th cpu - local cpu first

2014-06-11T21:58:16+00:00

This function sets the n'th cpu - local cpu's first. For example: in a 16 cores server with even cpu's local, will get the following values: cpumask_set_cpu_local_first(0, numa, cpumask) => cpu 0 is set cpumask_set_cpu_local_first(1, numa, cpumask) => cpu 2 is set ... cpumask_set_cpu_local_first(7, numa, cpumask) => cpu 14 is set cpumask_set_cpu_local_first(8, numa, cpumask) => cpu 1 is set cpumask_set_cpu_local_first(9, numa, cpumask) => cpu 3 is set ... cpumask_set_cpu_local_first(15, numa, cpumask) => cpu 15 is set Curently this function will be used by multi queue networking devices to calculate the irq affinity mask, such that as many local cpu's as possible will be utilized to handle the mq device irq's. Signed-off-by: Amir Vadai Signed-off-by: David S. Miller

net: Revert mlx4 cpumask changes.

2014-06-02T04:58:02+00:00

This reverts commit 70a640d0dae3a9b1b222ce673eb5d92c263ddd61 ("net/mlx4_en: Use affinity hint") and commit c8865b64b05b2f4eeefd369373e9c8aeb069e7a1 ("cpumask: Utility function to set n'th cpu - local cpu first") because these changes break the build when SMP is disabled amongst other things. Reported-by: Eric Dumazet Signed-off-by: David S. Miller

cpumask: Utility function to set n'th cpu - local cpu first

2014-06-02T02:16:29+00:00