Trying to use local APIC timer
I'm trying to use the local APIC timer to send interrupts after a certain interval (for a kernel module I am writing). This is not related to scheduling in Linux.
I set the clocksource in Linux to HPET so that I could free up the local APIC timer for my own use. However, whenever I write to the local APIC timer's registers, it seems that my values get overwritten shortly after by different code in the kernel.
Does anyone know where this is happening? How can I free up the local APIC timer for myself?
$ cat /sys/devices/system/clocksource/clocksource0/current_clocksource
hpet
linux linux-kernel kernel-modules interrupt
asked 5 mins ago
Jack HumphriesJack Humphries
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I'm trying to use the local APIC timer to send interrupts after a certain interval (for a kernel module I am writing). This is not related to scheduling in Linux.
I set the clocksource in Linux to HPET so that I could free up the local APIC timer for my own use. However, whenever I write to the local APIC timer's registers, it seems that my values get overwritten shortly after by different code in the kernel.
Does anyone know where this is happening? How can I free up the local APIC timer for myself?
$ cat /sys/devices/system/clocksource/clocksource0/current_clocksource
hpet
linux linux-kernel kernel-modules interrupt
asked 5 mins ago
Jack HumphriesJack Humphries
1011
New contributor
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
I'm trying to use the local APIC timer to send interrupts after a certain interval (for a kernel module I am writing). This is not related to scheduling in Linux.
I set the clocksource in Linux to HPET so that I could free up the local APIC timer for my own use. However, whenever I write to the local APIC timer's registers, it seems that my values get overwritten shortly after by different code in the kernel.
Does anyone know where this is happening? How can I free up the local APIC timer for myself?
$ cat /sys/devices/system/clocksource/clocksource0/current_clocksource
hpet
linux linux-kernel kernel-modules interrupt
asked 5 mins ago
Jack HumphriesJack Humphries
1011
New contributor
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I'm trying to use the local APIC timer to send interrupts after a certain interval (for a kernel module I am writing). This is not related to scheduling in Linux.
I set the clocksource in Linux to HPET so that I could free up the local APIC timer for my own use. However, whenever I write to the local APIC timer's registers, it seems that my values get overwritten shortly after by different code in the kernel.
Does anyone know where this is happening? How can I free up the local APIC timer for myself?
$ cat /sys/devices/system/clocksource/clocksource0/current_clocksource
hpet
linux linux-kernel kernel-modules interrupt
linux linux-kernel kernel-modules interrupt
asked 5 mins ago
Jack HumphriesJack Humphries
1011
New contributor
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 5 mins ago
Jack HumphriesJack Humphries
1011
New contributor
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 5 mins ago
Jack HumphriesJack Humphries
1011
New contributor
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 5 mins ago
Jack HumphriesJack Humphries
1011
asked 5 mins ago
Jack HumphriesJack Humphries
1011
1011
New contributor
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Jack Humphries is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
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