Re: [PATCH V3 5/5] ocxl: Add new kernel traces

[Frederic Barrat <fbarrat@linux.ibm.com>]

On 24/11/2020 10:58, Christophe Lombard wrote:
> Add specific kernel traces which provide information on mmu notifier and on
> pages range.
> 
> Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
> ---


Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>


>   drivers/misc/ocxl/link.c  |  4 +++
>   drivers/misc/ocxl/trace.h | 64 +++++++++++++++++++++++++++++++++++++++
>   2 files changed, 68 insertions(+)
> 
> diff --git a/drivers/misc/ocxl/link.c b/drivers/misc/ocxl/link.c
> index 129d4eddc4d2..ab039c115381 100644
> --- a/drivers/misc/ocxl/link.c
> +++ b/drivers/misc/ocxl/link.c
> @@ -499,6 +499,7 @@ static void invalidate_range(struct mmu_notifier *mn,
>   	unsigned long addr, pid, page_size = PAGE_SIZE;
> 
>   	pid = mm->context.id;
> +	trace_ocxl_mmu_notifier_range(start, end, pid);
> 
>   	spin_lock(&link->atsd_lock);
>   	for (addr = start; addr < end; addr += page_size)
> @@ -590,6 +591,7 @@ int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr,
>   			/* Use MMIO registers for the TLB Invalidate
>   			 * operations.
>   			 */
> +			trace_ocxl_init_mmu_notifier(pasid, mm->context.id);
>   			mmu_notifier_register(&pe_data->mmu_notifier, mm);
>   		}
>   	}
> @@ -725,6 +727,8 @@ int ocxl_link_remove_pe(void *link_handle, int pasid)
>   	} else {
>   		if (pe_data->mm) {
>   			if (link->arva) {
> +				trace_ocxl_release_mmu_notifier(pasid,
> +								pe_data->mm->context.id);
>   				mmu_notifier_unregister(&pe_data->mmu_notifier,
>   							pe_data->mm);
>   				spin_lock(&link->atsd_lock);
> diff --git a/drivers/misc/ocxl/trace.h b/drivers/misc/ocxl/trace.h
> index 17e21cb2addd..a33a5094ff6c 100644
> --- a/drivers/misc/ocxl/trace.h
> +++ b/drivers/misc/ocxl/trace.h
> @@ -8,6 +8,70 @@
> 
>   #include <linux/tracepoint.h>
> 
> +
> +TRACE_EVENT(ocxl_mmu_notifier_range,
> +	TP_PROTO(unsigned long start, unsigned long end, unsigned long pidr),
> +	TP_ARGS(start, end, pidr),
> +
> +	TP_STRUCT__entry(
> +		__field(unsigned long, start)
> +		__field(unsigned long, end)
> +		__field(unsigned long, pidr)
> +	),
> +
> +	TP_fast_assign(
> +		__entry->start = start;
> +		__entry->end = end;
> +		__entry->pidr = pidr;
> +	),
> +
> +	TP_printk("start=0x%lx end=0x%lx pidr=0x%lx",
> +		__entry->start,
> +		__entry->end,
> +		__entry->pidr
> +	)
> +);
> +
> +TRACE_EVENT(ocxl_init_mmu_notifier,
> +	TP_PROTO(int pasid, unsigned long pidr),
> +	TP_ARGS(pasid, pidr),
> +
> +	TP_STRUCT__entry(
> +		__field(int, pasid)
> +		__field(unsigned long, pidr)
> +	),
> +
> +	TP_fast_assign(
> +		__entry->pasid = pasid;
> +		__entry->pidr = pidr;
> +	),
> +
> +	TP_printk("pasid=%d, pidr=0x%lx",
> +		__entry->pasid,
> +		__entry->pidr
> +	)
> +);
> +
> +TRACE_EVENT(ocxl_release_mmu_notifier,
> +	TP_PROTO(int pasid, unsigned long pidr),
> +	TP_ARGS(pasid, pidr),
> +
> +	TP_STRUCT__entry(
> +		__field(int, pasid)
> +		__field(unsigned long, pidr)
> +	),
> +
> +	TP_fast_assign(
> +		__entry->pasid = pasid;
> +		__entry->pidr = pidr;
> +	),
> +
> +	TP_printk("pasid=%d, pidr=0x%lx",
> +		__entry->pasid,
> +		__entry->pidr
> +	)
> +);
> +
>   DECLARE_EVENT_CLASS(ocxl_context,
>   	TP_PROTO(pid_t pid, void *spa, int pasid, u32 pidr, u32 tidr),
>   	TP_ARGS(pid, spa, pasid, pidr, tidr),
>