summaryrefslogtreecommitdiff
path: root/arch/arm/include/asm/stacktrace.h
diff options
context:
space:
mode:
authorZhen Lei <thunder.leizhen@huawei.com>2022-08-25 07:31:54 +0100
committerRussell King (Oracle) <rmk+kernel@armlinux.org.uk>2022-08-31 14:50:08 +0100
commit370d51c84216d1a41f125f0b04614e677ffe54e3 (patch)
treefa1945f22dc9c5c248c0cb732752eee5f0a90af2 /arch/arm/include/asm/stacktrace.h
parentedd61fc1ca4c969c34b877f4aa9fb169138b80e3 (diff)
ARM: 9232/1: Replace this_cpu_* with raw_cpu_* in handle_bad_stack()
The hardware automatically disable the IRQ interrupt before jumping to the interrupt or exception vector. Therefore, the preempt_disable() operation in this_cpu_read() after macro expansion is unnecessary. In fact, function this_cpu_read() may trigger scheduling, see pseudocode below. Pseudocode of this_cpu_read(xx): preempt_disable_notrace(); raw_cpu_read(xx); if (unlikely(__preempt_count_dec_and_test())) __preempt_schedule_notrace(); Therefore, use raw_cpu_* instead of this_cpu_* to eliminate potential hazards. At the very least, it reduces a few lines of assembly code. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm/include/asm/stacktrace.h')
0 files changed, 0 insertions, 0 deletions