97c8580e85
Annotate cpu_wait implementations using the __cpuidle macro which places these functions in the .cpuidle.text section. This allows cpu_in_idle() to return true for PC values which fall within these functions, allowing nmi_backtrace() to produce cleaner output for CPUs running idle functions. For example: # echo l >/proc/sysrq-trigger [ 38.587170] sysrq: SysRq : Show backtrace of all active CPUs [ 38.593657] NMI backtrace for cpu 1 [ 38.597611] CPU: 1 PID: 161 Comm: sh Not tainted 4.18.0-rc1+ #27 [ 38.604306] Stack : 00000000 00000004 00000006 80486724 00000000 00000000 00000000 00000000 [ 38.613647] 80e17eda 00000034 00000000 00000000 80d20000 80b67e98 8e559c90 0ffe1e88 [ 38.622986] 00000000 00000000 80e70000 00000000 8f61db18 38312e34 722d302e 202b3163 [ 38.632324] 8e559d3c 8e559adc 00000001 6b636162 80d20000 80000000 00000000 80d1cfa4 [ 38.641664] 00000001 80d20000 80d19520 00000000 00000003 80836724 00000004 80e10004 [ 38.650993] ... [ 38.653724] Call Trace: [ 38.656499] [<8040cdd0>] show_stack+0xa0/0x144 [ 38.661475] [<80b67e98>] dump_stack+0xe8/0x120 [ 38.666455] [<80b6f6d4>] nmi_cpu_backtrace+0x1b4/0x1cc [ 38.672189] [<80b6f81c>] nmi_trigger_cpumask_backtrace+0x130/0x1e4 [ 38.679081] [<808295d8>] __handle_sysrq+0xc0/0x180 [ 38.684421] [<80829b84>] write_sysrq_trigger+0x50/0x64 [ 38.690176] [<8061c984>] proc_reg_write+0xd0/0xfc [ 38.695447] [<805aac1c>] __vfs_write+0x54/0x194 [ 38.700500] [<805aaf24>] vfs_write+0xe0/0x18c [ 38.705360] [<805ab190>] ksys_write+0x7c/0xf0 [ 38.710238] [<80416018>] syscall_common+0x34/0x58 [ 38.715558] Sending NMI from CPU 1 to CPUs 0,2-3: [ 38.720916] NMI backtrace for cpu 0 skipped: idling at r4k_wait_irqoff+0x2c/0x34 [ 38.729186] NMI backtrace for cpu 3 skipped: idling at r4k_wait_irqoff+0x2c/0x34 [ 38.737449] NMI backtrace for cpu 2 skipped: idling at r4k_wait_irqoff+0x2c/0x34 Without this we get register value & backtrace output from all CPUs, which is generally useless for those running the idle function & serves only to overwhelm & obfuscate the meaningful output from non-idle CPUs. Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Huacai Chen <chenhc@lemote.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/19598/ |
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casio-e55 | ||
common | ||
ibm-workpad | ||
Kconfig | ||
Platform |