[Intel-gfx] [PATCH i-g-t 01/11] lib: Helper library for parsing i915 fdinfo output
Tvrtko Ursulin
tvrtko.ursulin at linux.intel.com
Thu Mar 31 13:22:34 UTC 2022
On 30/03/2022 20:52, Umesh Nerlige Ramappa wrote:
> On Tue, Feb 22, 2022 at 01:55:55PM +0000, Tvrtko Ursulin wrote:
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> Tests and intel_gpu_top will share common code for parsing this file.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>> ---
>> lib/igt_drm_fdinfo.c | 183 +++++++++++++++++++++++++++++++++++++++++++
>> lib/igt_drm_fdinfo.h | 48 ++++++++++++
>> lib/meson.build | 7 ++
>> 3 files changed, 238 insertions(+)
>> create mode 100644 lib/igt_drm_fdinfo.c
>> create mode 100644 lib/igt_drm_fdinfo.h
>>
>> diff --git a/lib/igt_drm_fdinfo.c b/lib/igt_drm_fdinfo.c
>> new file mode 100644
>> index 000000000000..28c1bdbda08e
>> --- /dev/null
>> +++ b/lib/igt_drm_fdinfo.c
>> @@ -0,0 +1,183 @@
>> +/*
>> + * Copyright © 2022 Intel Corporation
>> + *
>> + * Permission is hereby granted, free of charge, to any person
>> obtaining a
>> + * copy of this software and associated documentation files (the
>> "Software"),
>> + * to deal in the Software without restriction, including without
>> limitation
>> + * the rights to use, copy, modify, merge, publish, distribute,
>> sublicense,
>> + * and/or sell copies of the Software, and to permit persons to whom the
>> + * Software is furnished to do so, subject to the following conditions:
>> + *
>> + * The above copyright notice and this permission notice (including
>> the next
>> + * paragraph) shall be included in all copies or substantial portions
>> of the
>> + * Software.
>> + *
>> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
>> EXPRESS OR
>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
>> MERCHANTABILITY,
>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
>> SHALL
>> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
>> OR OTHER
>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
>> ARISING
>> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
>> OTHER DEALINGS
>> + * IN THE SOFTWARE.
>> + *
>> + */
>> +
>> +#include <ctype.h>
>> +#include <sys/types.h>
>> +#include <sys/stat.h>
>> +#include <fcntl.h>
>> +#include <stdio.h>
>> +#include <string.h>
>> +#include <stdlib.h>
>> +#include <unistd.h>
>> +
>> +#include "drmtest.h"
>> +
>> +#include "igt_drm_fdinfo.h"
>> +
>> +static size_t read_fdinfo(char *buf, const size_t sz, int at, const
>> char *name)
>> +{
>> + size_t count;
>> + int fd;
>> +
>> + fd = openat(at, name, O_RDONLY);
>> + if (fd < 0)
>> + return 0;
>> +
>> + buf[sz - 1] = 0;
>
> Wondering if this ^ should be after the read() in case 4096 bytes are read.
Yes, I guess even before and after so it's guaranteed to be null
terminated no matter what.
>
>> + count = read(fd, buf, sz);
>> + close(fd);
>> +
>> + return count;
>> +}
>> +
>> +static int parse_engine(char *line, struct drm_client_fdinfo *info,
>> + size_t prefix_len, uint64_t *val)
>> +{
>> + static const char *e2class[] = {
>> + "render",
>> + "copy",
>> + "video",
>> + "video-enhance",
>> + };
>> + ssize_t name_len;
>> + char *name, *p;
>> + int found = -1;
>> + unsigned int i;
>> +
>> + p = index(line, ':');
>> + if (!p || p == line)
>> + return -1;
>> +
>> + name_len = p - line - prefix_len;
>> + if (name_len < 1)
>> + return -1;
>> +
>> + name = line + prefix_len;
>> +
>> + for (i = 0; i < ARRAY_SIZE(e2class); i++) {
>> + if (!strncmp(name, e2class[i], name_len)) {
>> + found = i;
>> + break;
>> + }
>> + }
>> +
>> + if (found >= 0) {
>> + while (*++p && isspace(*p));
>> + *val = strtoull(p, NULL, 10);
>> + }
>> +
>> + return found;
>> +}
>> +
>> +static const char *find_kv(const char *buf, const char *key, size_t
>> keylen)
>> +{
>> + const char *p = buf;
>> +
>> + p = index(buf, ':');
>> + if (!p || p == buf)
>> + return NULL;
>> +
>> + if ((p - buf) != keylen)
>> + return NULL;
>> +
>> + while (*++p && isspace(*p));
>> + if (*p && !strncmp(buf, key, keylen))
>
> nit: why not just do the strncmp early in this function since buf, key,
> keylen have not changed?
I see what you mean, first check that the key/prefix matches and do the
other checks, right?
I honestly don't remember if there was a special reason why I laid it
out like it is. I know it is an annoyingly hot path and I did do many
tweaks to bring the CPU utilisation low.
But thinking about it now, the strncmp at the start should indeed be
more efficient so I will change it.
>
>> + return p;
>> +
>> + return NULL;
>> +}
>> +
>> +bool
>> +__igt_parse_drm_fdinfo(int dir, const char *fd, struct
>> drm_client_fdinfo *info)
>> +{
>> + char buf[4096], *_buf = buf;
>> + char *l, *ctx = NULL;
>> + unsigned int good = 0;
>> + size_t count;
>> +
>
> Should buf be zeroed out here?
Right, either here or in read_fdinfo as mentioned above.
>> + count = read_fdinfo(buf, sizeof(buf), dir, fd);
>> + if (!count)
>> + return false;
>> +
>> + while ((l = strtok_r(_buf, "\n", &ctx))) {
>> + uint64_t val = 0;
>> + const char *v;
>> + int idx;
>> +
>> + _buf = NULL;
>> +
>> + if ((v = find_kv(l, "drm-driver", strlen("drm-driver")))) {
>> + strncpy(info->driver, v, sizeof(info->driver) - 1);
>> + good++;
>> + } else if ((v = find_kv(l, "drm-pdev", strlen("drm-pdev")))) {
>> + strncpy(info->pdev, v, sizeof(info->pdev) - 1);
>> + } else if ((v = find_kv(l, "drm-client-id",
>> + strlen("drm-client-id")))) {
>> + info->id = atol(v);
>> + good++;
>> + } else if (!strncmp(l, "drm-engine-", 11) &&
>> + strncmp(l, "drm-engine-capacity-", 20)) {
>> + idx = parse_engine(l, info, strlen("drm-engine-"),
>> + &val);
>> + if (idx >= 0) {
>> + if (!info->capacity[idx])
>> + info->capacity[idx] = 1;
>> + info->busy[idx] = val;
>> + info->num_engines++;
>> + }
>> + } else if (!strncmp(l, "drm-engine-capacity-", 20)) {
>> + idx = parse_engine(l, info,
>> + strlen("drm-engine-capacity-"),
>> + &val);
>> + if (idx >= 0)
>> + info->capacity[idx] = val;
>> + }
>> + }
>> +
>> + if (good < 2 || !info->num_engines)
>> + return false; /* fdinfo format not as expected */
>> +
>> + return true;
>> +}
>> +
>> +bool igt_parse_drm_fdinfo(int drm_fd, struct drm_client_fdinfo *info)
>> +{
>> + char fd[64];
>> + int dir, ret;
>> + bool res;
>> +
>> + ret = snprintf(fd, sizeof(fd), "%u", drm_fd);
>> + if (ret < 0 || ret == sizeof(fd))
>> + return false;
>> +
>> + dir = open("/proc/self/fdinfo", O_DIRECTORY | O_RDONLY);
>> + if (dir < 0)
>> + return false;
>> +
>> + res = __igt_parse_drm_fdinfo(dir, fd, info);
>> +
>> + close(dir);
>> +
>> + return res;
>> +}
>> diff --git a/lib/igt_drm_fdinfo.h b/lib/igt_drm_fdinfo.h
>> new file mode 100644
>> index 000000000000..c527bab9a204
>> --- /dev/null
>> +++ b/lib/igt_drm_fdinfo.h
>> @@ -0,0 +1,48 @@
>> +/*
>> + * Copyright © 2022 Intel Corporation
>> + *
>> + * Permission is hereby granted, free of charge, to any person
>> obtaining a
>> + * copy of this software and associated documentation files (the
>> "Software"),
>> + * to deal in the Software without restriction, including without
>> limitation
>> + * the rights to use, copy, modify, merge, publish, distribute,
>> sublicense,
>> + * and/or sell copies of the Software, and to permit persons to whom the
>> + * Software is furnished to do so, subject to the following conditions:
>> + *
>> + * The above copyright notice and this permission notice (including
>> the next
>> + * paragraph) shall be included in all copies or substantial portions
>> of the
>> + * Software.
>> + *
>> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
>> EXPRESS OR
>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
>> MERCHANTABILITY,
>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
>> SHALL
>> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
>> OR OTHER
>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
>> ARISING
>> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
>> OTHER DEALINGS
>> + * IN THE SOFTWARE.
>> + *
>> + */
>> +
>> +#ifndef IGT_DRM_FDINFO_H
>> +#define IGT_DRM_FDINFO_H
>> +
>> +#include <sys/types.h>
>> +#include <dirent.h>
>> +#include <stdint.h>
>> +#include <stdbool.h>
>> +
>> +struct drm_client_fdinfo {
>> + char driver[128];
>> + char pdev[128];
>> + unsigned long id;
>> +
>> + unsigned int num_engines;
>> + unsigned int capacity[16];
>> + uint64_t busy[16];
>
> I see 16 in a lot of places, wondering if it could use a #define?
I can see them here and one mention in igt_drm_clients. The latter it
looks I can un-export igt_drm_client_update and make it take struct
drm_client_fdinfo to better hide this.
And for here I will add a define like DRM_CLIENT_FDINFO_MAX_ENGINES.
Regards,
Tvrtko
>
> Thanks,
> Umesh
>
>> +};
>> +
>> +bool igt_parse_drm_fdinfo(int drm_fd, struct drm_client_fdinfo *info);
>> +
>> +bool __igt_parse_drm_fdinfo(int dir, const char *fd,
>> + struct drm_client_fdinfo *info);
>> +
>> +#endif /* IGT_DRM_FDINFO_H */
>> diff --git a/lib/meson.build b/lib/meson.build
>> index 3e43316d1e36..d00817dc58bc 100644
>> --- a/lib/meson.build
>> +++ b/lib/meson.build
>> @@ -16,6 +16,7 @@ lib_sources = [
>> 'igt_debugfs.c',
>> 'igt_device.c',
>> 'igt_device_scan.c',
>> + 'igt_drm_fdinfo.c',
>> 'igt_aux.c',
>> 'igt_gt.c',
>> 'igt_halffloat.c',
>> @@ -216,6 +217,12 @@ lib_igt_device_scan_build =
>> static_library('igt_device_scan',
>> lib_igt_device_scan = declare_dependency(link_with :
>> lib_igt_device_scan_build,
>> include_directories : inc)
>>
>> +lib_igt_drm_fdinfo_build = static_library('igt_drm_fdinfo',
>> + ['igt_drm_fdinfo.c'],
>> + include_directories : inc)
>> +
>> +lib_igt_drm_fdinfo = declare_dependency(link_with :
>> lib_igt_drm_fdinfo_build,
>> + include_directories : inc)
>> i915_perf_files = [
>> 'igt_list.c',
>> 'i915/perf.c',
>> --
>> 2.32.0
>>
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