Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
tools/sched_ext: scx_pair: fix stride == 0 crash on single-CPU systems
nr_cpu_ids / 2 produces stride 0 on a single-CPU system, which later
causes SCX_BUG_ON(i == j) to fire. Validate stride after option
parsing to also catch invalid user-supplied values via -S.
Signed-off-by: David Carlier <devnexen@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
authored by
David Carlier
and committed by
Tejun Heo
625be345
55a24d92
+6
-1
+6
-1
tools/sched_ext/scx_pair.c
+6
-1
tools/sched_ext/scx_pair.c
···
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skel = SCX_OPS_OPEN(pair_ops, scx_pair);
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skel->rodata->nr_cpu_ids = libbpf_num_possible_cpus();
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assert(skel->rodata->nr_cpu_ids > 0);
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skel->rodata->pair_batch_dur_ns = __COMPAT_ENUM_OR_ZERO("scx_public_consts", "SCX_SLICE_DFL");
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/* pair up the earlier half to the latter by default, override with -s */
···
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}
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}
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/* Stride must be positive to pair distinct CPUs. */
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if (stride <= 0) {
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fprintf(stderr, "Invalid stride %d, must be positive\n", stride);
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scx_pair__destroy(skel);
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return -1;
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}
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bpf_map__set_max_entries(skel->maps.pair_ctx, skel->rodata->nr_cpu_ids / 2);
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/* Resize arrays so their element count is equal to cpu count. */