Present an interface for system monitors to watch the GPU usage as a whole and by individual applications. By consolidating the information into a canonical location, we have a single interface that can track the utilisation of all GPU devices and sub-devices. This is preferrable to asking the system monitors to walk the sysfs, or other interfaces, of each device and parse the custom information presented by each driver.
Opens: - Should we try to name each channel so that it can be shown in UI?
In gnome-system-monitor, we would have a task list: Process ... GPU0% GPU1% and charts that would show the GPU% on/next the CPU overview.
Then we could have a futher expansion of a GPU% into per-channel utilisation. That would be useful to check to see what is saturating a particular channel, e.g. find the video decoder bottleneck.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk --- fs/proc/Makefile | 1 + fs/proc/base.c | 2 + fs/proc/gpu.c | 83 ++++++++++++++++++++++++++++++++++++++++ fs/proc/internal.h | 6 +++ include/linux/proc_gpu.h | 33 ++++++++++++++++ 5 files changed, 125 insertions(+) create mode 100644 fs/proc/gpu.c create mode 100644 include/linux/proc_gpu.h
diff --git a/fs/proc/Makefile b/fs/proc/Makefile index bd08616ed8ba..bdc42b592e3e 100644 --- a/fs/proc/Makefile +++ b/fs/proc/Makefile @@ -16,6 +16,7 @@ proc-y += cmdline.o proc-y += consoles.o proc-y += cpuinfo.o proc-y += devices.o +proc-y += gpu.o proc-y += interrupts.o proc-y += loadavg.o proc-y += meminfo.o diff --git a/fs/proc/base.c b/fs/proc/base.c index b3422cda2a91..062298f5f6c8 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -3266,6 +3266,7 @@ static const struct pid_entry tgid_base_stuff[] = { #ifdef CONFIG_SECCOMP_CACHE_DEBUG ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache), #endif + ONE("gpu", S_IRUGO, proc_pid_gpu), };
static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) @@ -3598,6 +3599,7 @@ static const struct pid_entry tid_base_stuff[] = { #ifdef CONFIG_SECCOMP_CACHE_DEBUG ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache), #endif + ONE("gpu", S_IRUGO, proc_pid_gpu), };
static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) diff --git a/fs/proc/gpu.c b/fs/proc/gpu.c new file mode 100644 index 000000000000..7264bf1f2f7b --- /dev/null +++ b/fs/proc/gpu.c @@ -0,0 +1,83 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/proc_fs.h> +#include <linux/proc_gpu.h> +#include <linux/seq_file.h> +#include <linux/spinlock.h> +#include <linux/list.h> + +#include "internal.h" + +static LIST_HEAD(gpu); +static DEFINE_SPINLOCK(lock); + +void proc_gpu_register(struct proc_gpu *pg) +{ + spin_lock(&lock); + list_add_tail(&pg->link, &gpu); + spin_unlock(&lock); +} +EXPORT_SYMBOL_GPL(proc_gpu_register); + +void proc_gpu_unregister(struct proc_gpu *pg) +{ + spin_lock(&lock); + list_del(&pg->link); + spin_unlock(&lock); +} +EXPORT_SYMBOL_GPL(proc_gpu_unregister); + +static void print_runtime(struct seq_file *m, const struct proc_gpu_runtime *rt) +{ + int i; + + seq_printf(m, "%llu", rt->device); + + for (i = 0; i < rt->nchannel; i++) + seq_printf(m, " %llu", rt->channel[i]); + + seq_printf(m, " %s\n", rt->name); +} + +int proc_pid_gpu(struct seq_file *m, struct pid_namespace *ns, + struct pid *pid, struct task_struct *task) +{ + struct proc_gpu *p, *pn, mark = {}; + struct proc_gpu_runtime rt; + + spin_lock(&lock); + list_for_each_entry_safe(p, pn, &gpu, link) { + if (!p->fn) + continue; + + rt.name[0] = '\0'; + p->fn(p, pid, &rt); + if (!rt.name[0]) + continue; + + list_add(&mark.link, &p->link); + spin_unlock(&lock); + + print_runtime(m, &rt); + + spin_lock(&lock); + list_safe_reset_next(&mark, pn, link); + list_del(&mark.link); + } + spin_unlock(&lock); + + return 0; +} + +static int proc_gpu_show(struct seq_file *m, void *v) +{ + return proc_pid_gpu(m, NULL, NULL, NULL); +} + +static int __init proc_gpu_init(void) +{ + proc_create_single("gpu", 0, NULL, proc_gpu_show); + return 0; +} +fs_initcall(proc_gpu_init); diff --git a/fs/proc/internal.h b/fs/proc/internal.h index f60b379dcdc7..08bf45bec975 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -221,6 +221,12 @@ void set_proc_pid_nlink(void); extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *); extern void proc_entry_rundown(struct proc_dir_entry *);
+/* + * proc_gpu.c + */ +int proc_pid_gpu(struct seq_file *m, struct pid_namespace *ns, + struct pid *pid, struct task_struct *task); + /* * proc_namespaces.c */ diff --git a/include/linux/proc_gpu.h b/include/linux/proc_gpu.h new file mode 100644 index 000000000000..05c1db951c80 --- /dev/null +++ b/include/linux/proc_gpu.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Interface for showing per-gpu/per-process runtimes in /proc. + */ +#ifndef _LINUX_PROC_GPU_H +#define _LINUX_PROC_GPU_H + +#include <linux/list.h> +#include <linux/types.h> + +struct pid; +struct proc_gpu; + +struct proc_gpu_runtime { + char name[60]; + int nchannel; + u64 device; + u64 channel[64]; +}; + +typedef void (*proc_gpu_fn_t)(struct proc_gpu *arg, + struct pid *pid, + struct proc_gpu_runtime *rt); + +struct proc_gpu { + struct list_head link; + proc_gpu_fn_t fn; +}; + +void proc_gpu_register(struct proc_gpu *pg); +void proc_gpu_unregister(struct proc_gpu *pg); + +#endif /* _LINUX_PROC_GPU_H */