diff options
| author | Paul Burton <paul.burton@mips.com> | 2018-06-22 10:55:47 -0700 |
|---|---|---|
| committer | Paul Burton <paul.burton@mips.com> | 2018-06-28 14:18:54 -0700 |
| commit | 97c8580e85cf81cbc785102a1180f81ff431b1f0 (patch) | |
| tree | a964b7bb7a7a1fde20ec1d8dbf3c2770169af5ed /arch/mips/kernel/idle.c | |
| parent | 829caee7e38273ef27d64207578d4653979c525e (diff) | |
MIPS: Annotate cpu_wait implementations with __cpuidle
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/
Diffstat (limited to 'arch/mips/kernel/idle.c')
| -rw-r--r-- | arch/mips/kernel/idle.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c index 7c246b69c545..046846999efd 100644 --- a/arch/mips/kernel/idle.c +++ b/arch/mips/kernel/idle.c @@ -33,21 +33,21 @@ void (*cpu_wait)(void); EXPORT_SYMBOL(cpu_wait); -static void r3081_wait(void) +static void __cpuidle r3081_wait(void) { unsigned long cfg = read_c0_conf(); write_c0_conf(cfg | R30XX_CONF_HALT); local_irq_enable(); } -static void r39xx_wait(void) +static void __cpuidle r39xx_wait(void) { if (!need_resched()) write_c0_conf(read_c0_conf() | TX39_CONF_HALT); local_irq_enable(); } -void r4k_wait(void) +void __cpuidle r4k_wait(void) { local_irq_enable(); __r4k_wait(); @@ -60,7 +60,7 @@ void r4k_wait(void) * interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes * using this version a gamble. */ -void r4k_wait_irqoff(void) +void __cpuidle r4k_wait_irqoff(void) { if (!need_resched()) __asm__( @@ -75,7 +75,7 @@ void r4k_wait_irqoff(void) * The RM7000 variant has to handle erratum 38. The workaround is to not * have any pending stores when the WAIT instruction is executed. */ -static void rm7k_wait_irqoff(void) +static void __cpuidle rm7k_wait_irqoff(void) { if (!need_resched()) __asm__( @@ -96,7 +96,7 @@ static void rm7k_wait_irqoff(void) * since coreclock (and the cp0 counter) stops upon executing it. Only an * interrupt can wake it, so they must be enabled before entering idle modes. */ -static void au1k_wait(void) +static void __cpuidle au1k_wait(void) { unsigned long c0status = read_c0_status() | 1; /* irqs on */ |