[PATCH v2] drm/amdkfd: Differentiate logging message for driver oversubscription

[Kasiviswanathan, Harish]

[AMD Official Use Only - AMD Internal Distribution Only]

I would change the message slightly. See below. But either way this patch is Reviewed-by: Harish Kasiviswanathan <Harish.Kasiviswanathan at amd.com>

-----Original Message-----
From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> On Behalf Of Xiaogang.Chen
Sent: Tuesday, November 12, 2024 1:26 PM
To: amd-gfx at lists.freedesktop.org
Cc: Kuehling, Felix <Felix.Kuehling at amd.com>; Joshi, Mukul <Mukul.Joshi at amd.com>; Chen, Xiaogang <Xiaogang.Chen at amd.com>
Subject: [PATCH v2] drm/amdkfd: Differentiate logging message for driver oversubscription

From: Xiaogang Chen <xiaogang.chen at amd.com>

To have user better understand the causes triggering runlist oversubscription.
No function change.

Signed-off-by: Xiaogang Chen Xiaogang.Chen at amd.com
---
 .../gpu/drm/amd/amdkfd/kfd_packet_manager.c   | 44 +++++++++++++------
 1 file changed, 30 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c
index 37930629edc5..1848578dd5a9 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c
@@ -28,6 +28,10 @@
 #include "kfd_kernel_queue.h"
 #include "kfd_priv.h"

+#define OVER_SUBSCRIPTION_PROCESS_COUNT (1 << 0)
+#define OVER_SUBSCRIPTION_COMPUTE_QUEUE_COUNT (1 << 1)
+#define OVER_SUBSCRIPTION_GWS_QUEUE_COUNT (1 << 2)
+
 static inline void inc_wptr(unsigned int *wptr, unsigned int increment_bytes,
                                unsigned int buffer_size_bytes)
 {
@@ -40,7 +44,7 @@ static inline void inc_wptr(unsigned int *wptr, unsigned int increment_bytes,

 static void pm_calc_rlib_size(struct packet_manager *pm,
                                unsigned int *rlib_size,
-                               bool *over_subscription)
+                               int *over_subscription)
 {
        unsigned int process_count, queue_count, compute_queue_count, gws_queue_count;
        unsigned int map_queue_size;
@@ -58,17 +62,20 @@ static void pm_calc_rlib_size(struct packet_manager *pm,
         * hws_max_conc_proc has been done in
         * kgd2kfd_device_init().
         */
-       *over_subscription = false;
+       *over_subscription = 0;

        if (node->max_proc_per_quantum > 1)
                max_proc_per_quantum = node->max_proc_per_quantum;

-       if ((process_count > max_proc_per_quantum) ||
-           compute_queue_count > get_cp_queues_num(pm->dqm) ||
-           gws_queue_count > 1) {
-               *over_subscription = true;
+       if (process_count > max_proc_per_quantum)
+               *over_subscription |= OVER_SUBSCRIPTION_PROCESS_COUNT;
+       if (compute_queue_count > get_cp_queues_num(pm->dqm))
+               *over_subscription |= OVER_SUBSCRIPTION_COMPUTE_QUEUE_COUNT;
+       if (gws_queue_count > 1)
+               *over_subscription |= OVER_SUBSCRIPTION_GWS_QUEUE_COUNT;
+
+       if (*over_subscription)
                dev_dbg(dev, "Over subscribed runlist\n");
-       }

        map_queue_size = pm->pmf->map_queues_size;
        /* calculate run list ib allocation size */
@@ -89,7 +96,7 @@ static int pm_allocate_runlist_ib(struct packet_manager *pm,
                                unsigned int **rl_buffer,
                                uint64_t *rl_gpu_buffer,
                                unsigned int *rl_buffer_size,
-                               bool *is_over_subscription)
+                               int *is_over_subscription)
 {
        struct kfd_node *node = pm->dqm->dev;
        struct device *dev = node->adev->dev;
@@ -134,7 +141,7 @@ static int pm_create_runlist_ib(struct packet_manager *pm,
        struct qcm_process_device *qpd;
        struct queue *q;
        struct kernel_queue *kq;
-       bool is_over_subscription;
+       int is_over_subscription;

        rl_wptr = retval = processes_mapped = 0;

@@ -212,16 +219,25 @@ static int pm_create_runlist_ib(struct packet_manager *pm,
        dev_dbg(dev, "Finished map process and queues to runlist\n");

        if (is_over_subscription) {
-               if (!pm->is_over_subscription)
-                       dev_warn(
-                               dev,
-                               "Runlist is getting oversubscribed. Expect reduced ROCm performance.\n");
+               if (!pm->is_over_subscription) {
+
+                       dev_warn(dev, "Runlist is getting oversubscribed due to%s%s%s."
+                               " Expect reduced ROCm performance.\n",
+                               is_over_subscription & OVER_SUBSCRIPTION_PROCESS_COUNT ?
+                               " number of processes more than maximum number of processes"
+                               " that HWS can schedule concurrently." : "",

Number of processes are more than hardware VM slots available

+                               is_over_subscription & OVER_SUBSCRIPTION_COMPUTE_QUEUE_COUNT ?
+                               " number of queues is more than assigned compute queues." : "",
Number of compute queues exceeds what can be mapped to hardware at a given time

+                               is_over_subscription & OVER_SUBSCRIPTION_GWS_QUEUE_COUNT ?
+                               " cooperative launch is more than allowed." : "");
+
+               }
                retval = pm->pmf->runlist(pm, &rl_buffer[rl_wptr],
                                        *rl_gpu_addr,
                                        alloc_size_bytes / sizeof(uint32_t),
                                        true);
        }
-       pm->is_over_subscription = is_over_subscription;
+       pm->is_over_subscription = is_over_subscription ? true : false;

        for (i = 0; i < alloc_size_bytes / sizeof(uint32_t); i++)
                pr_debug("0x%2X ", rl_buffer[i]);
--
2.25.1