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author | Paul Burton <paul.burton@mips.com> | 2018-06-22 19:55:47 +0200 |
---|---|---|
committer | Paul Burton <paul.burton@mips.com> | 2018-06-28 23:18:54 +0200 |
commit | 97c8580e85cf81cbc785102a1180f81ff431b1f0 (patch) | |
tree | a964b7bb7a7a1fde20ec1d8dbf3c2770169af5ed /arch/mips/vr41xx | |
parent | arch: mips: mm: page: Remove unused function (diff) | |
download | linux-97c8580e85cf81cbc785102a1180f81ff431b1f0.tar.xz linux-97c8580e85cf81cbc785102a1180f81ff431b1f0.zip |
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/vr41xx')
-rw-r--r-- | arch/mips/vr41xx/common/pmu.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/mips/vr41xx/common/pmu.c b/arch/mips/vr41xx/common/pmu.c index 39a0db3e2b34..16e684b59875 100644 --- a/arch/mips/vr41xx/common/pmu.c +++ b/arch/mips/vr41xx/common/pmu.c @@ -17,6 +17,7 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include <linux/cpu.h> #include <linux/errno.h> #include <linux/init.h> #include <linux/ioport.h> @@ -46,7 +47,7 @@ static void __iomem *pmu_base; #define pmu_read(offset) readw(pmu_base + (offset)) #define pmu_write(offset, value) writew((value), pmu_base + (offset)) -static void vr41xx_cpu_wait(void) +static void __cpuidle vr41xx_cpu_wait(void) { local_irq_disable(); if (!need_resched()) |