[v2,bpf-next,1/2] drm, bpf: Move drm_mm.c to lib to be used by bpf arena

Commit Message

Alexei Starovoitov Nov. 5, 2024, 9:20 p.m. UTC

From: Alexei Starovoitov <[e-mail]>

Move drm_mm.c to lib:
- The next commit will use drm_mm to manage memory regions
  in bpf arena.
- Move drm_mm_print to drivers/gpu/drm/drm_print.c, since
  it's not a core functionality of drm_mm and it depeneds
  on drm_printer while drm_mm is generic and usuable as-is
  by other subsystems.
- Replace DRM_ERROR with pr_err to fix build.
  DRM_ERROR is deprecated in favor of pr_err anyway.
- Also add __maybe_unused to suppress compiler warnings.
- Update MAINTAINERS file as well.

Acked-by: Kumar Kartikeya Dwivedi <[e-mail]>
Signed-off-by: Alexei Starovoitov <[e-mail]>
---
 MAINTAINERS                       |  1 +
 drivers/gpu/drm/Makefile          |  1 -
 drivers/gpu/drm/drm_print.c       | 39 +++++++++++++++++++++++++
 lib/Makefile                      |  1 +
 {drivers/gpu/drm => lib}/drm_mm.c | 48 ++++---------------------------
 5 files changed, 46 insertions(+), 44 deletions(-)
 rename {drivers/gpu/drm => lib}/drm_mm.c (95%)

Comments

Alexei Starovoitov Nov. 8, 2024, 1:20 a.m. UTC | #1

On Tue, Nov 5, 2024 at 1:20 PM Alexei Starovoitov
<[e-mail]> wrote:
>
> From: Alexei Starovoitov <[e-mail]>
>
> Move drm_mm.c to lib:
> - The next commit will use drm_mm to manage memory regions
>   in bpf arena.
> - Move drm_mm_print to drivers/gpu/drm/drm_print.c, since
>   it's not a core functionality of drm_mm and it depeneds
>   on drm_printer while drm_mm is generic and usuable as-is
>   by other subsystems.
> - Replace DRM_ERROR with pr_err to fix build.
>   DRM_ERROR is deprecated in favor of pr_err anyway.
> - Also add __maybe_unused to suppress compiler warnings.
> - Update MAINTAINERS file as well.
>
> Acked-by: Kumar Kartikeya Dwivedi <[e-mail]>
> Signed-off-by: Alexei Starovoitov <[e-mail]>
> ---
>  MAINTAINERS                       |  1 +
>  drivers/gpu/drm/Makefile          |  1 -
>  drivers/gpu/drm/drm_print.c       | 39 +++++++++++++++++++++++++
>  lib/Makefile                      |  1 +
>  {drivers/gpu/drm => lib}/drm_mm.c | 48 ++++---------------------------
>  5 files changed, 46 insertions(+), 44 deletions(-)
>  rename {drivers/gpu/drm => lib}/drm_mm.c (95%)

DRM folks seem unresponsive :(
A simple move of the file shouldn't take a week to acknowledge.
I had plans to tailor drm_mm to bpf needs, but at this pace
it will take too long, so I'm abandoning this approach
and going a different route. It was worth a try. Fail fast.

pw-bot: cr

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 6880a8fac74c..1bfaa335fae7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7504,6 +7504,7 @@  F:	drivers/gpu/vga/
 F:	include/drm/drm
 F:	include/linux/vga*
 F:	include/uapi/drm/
+F:	lib/drm_mm.c
 X:	drivers/gpu/drm/amd/
 X:	drivers/gpu/drm/armada/
 X:	drivers/gpu/drm/etnaviv/
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 784229d4504d..e35d5de2b9f0 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -59,7 +59,6 @@  drm-y := \
 	drm_ioctl.o \
 	drm_lease.o \
 	drm_managed.o \
-	drm_mm.o \
 	drm_mode_config.o \
 	drm_mode_object.o \
 	drm_modes.o \
diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index 0081190201a7..2a8a5e0d691e 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -34,6 +34,7 @@ 
 #include <drm/drm.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_print.h>
+#include <drm/drm_mm.h>
 
 /*
  * __drm_debug: Enable debug output.
@@ -267,6 +268,44 @@  void drm_printf(struct drm_printer *p, const char *f, ...)
 }
 EXPORT_SYMBOL(drm_printf);
 
+static u64 drm_mm_dump_hole(struct drm_printer *p, const struct drm_mm_node *entry)
+{
+	u64 start, size;
+
+	size = entry->hole_size;
+	if (size) {
+		start = drm_mm_hole_node_start(entry);
+		drm_printf(p, "%#018llx-%#018llx: %llu: free\n",
+			   start, start + size, size);
+	}
+
+	return size;
+}
+/**
+ * drm_mm_print - print allocator state
+ * @mm: drm_mm allocator to print
+ * @p: DRM printer to use
+ */
+void drm_mm_print(const struct drm_mm *mm, struct drm_printer *p)
+{
+	const struct drm_mm_node *entry;
+	u64 total_used = 0, total_free = 0, total = 0;
+
+	total_free += drm_mm_dump_hole(p, &mm->head_node);
+
+	drm_mm_for_each_node(entry, mm) {
+		drm_printf(p, "%#018llx-%#018llx: %llu: used\n", entry->start,
+			   entry->start + entry->size, entry->size);
+		total_used += entry->size;
+		total_free += drm_mm_dump_hole(p, entry);
+	}
+	total = total_free + total_used;
+
+	drm_printf(p, "total: %llu, used %llu free %llu\n", total,
+		   total_used, total_free);
+}
+EXPORT_SYMBOL(drm_mm_print);
+
 /**
  * drm_print_bits - print bits to a &drm_printer stream
  *
diff --git a/lib/Makefile b/lib/Makefile
index 773adf88af41..320ae0ac227c 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -58,6 +58,7 @@  obj-$(CONFIG_TEST_HEXDUMP) += test_hexdump.o
 obj-y += kstrtox.o
 obj-$(CONFIG_FIND_BIT_BENCHMARK) += find_bit_benchmark.o
 obj-$(CONFIG_TEST_BPF) += test_bpf.o
+lib-$(CONFIG_DRM) += drm_mm.o
 test_dhry-objs := dhry_1.o dhry_2.o dhry_run.o
 obj-$(CONFIG_TEST_DHRY) += test_dhry.o
 obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o
diff --git a/drivers/gpu/drm/drm_mm.c b/lib/drm_mm.c
similarity index 95%
rename from drivers/gpu/drm/drm_mm.c
rename to lib/drm_mm.c
index 5ace481c1901..c6feaf325fac 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/lib/drm_mm.c
@@ -126,14 +126,14 @@  static void show_leaks(struct drm_mm *mm)
 
 	list_for_each_entry(node, drm_mm_nodes(mm), node_list) {
 		if (!node->stack) {
-			DRM_ERROR("node [%08llx + %08llx]: unknown owner\n",
-				  node->start, node->size);
+			pr_err("node [%08llx + %08llx]: unknown owner\n",
+			       node->start, node->size);
 			continue;
 		}
 
 		stack_depot_snprint(node->stack, buf, BUFSZ, 0);
-		DRM_ERROR("node [%08llx + %08llx]: inserted at\n%s",
-			  node->start, node->size, buf);
+		pr_err("node [%08llx + %08llx]: inserted at\n%s",
+		       node->start, node->size, buf);
 	}
 
 	kfree(buf);
@@ -151,7 +151,7 @@  static void show_leaks(struct drm_mm *mm) { }
 
 INTERVAL_TREE_DEFINE(struct drm_mm_node, rb,
 		     u64, __subtree_last,
-		     START, LAST, static inline, drm_mm_interval_tree)
+		     START, LAST, static inline __maybe_unused, drm_mm_interval_tree)
 
 struct drm_mm_node *
 __drm_mm_interval_first(const struct drm_mm *mm, u64 start, u64 last)
@@ -966,41 +966,3 @@  void drm_mm_takedown(struct drm_mm *mm)
 		show_leaks(mm);
 }
 EXPORT_SYMBOL(drm_mm_takedown);
-
-static u64 drm_mm_dump_hole(struct drm_printer *p, const struct drm_mm_node *entry)
-{
-	u64 start, size;
-
-	size = entry->hole_size;
-	if (size) {
-		start = drm_mm_hole_node_start(entry);
-		drm_printf(p, "%#018llx-%#018llx: %llu: free\n",
-			   start, start + size, size);
-	}
-
-	return size;
-}
-/**
- * drm_mm_print - print allocator state
- * @mm: drm_mm allocator to print
- * @p: DRM printer to use
- */
-void drm_mm_print(const struct drm_mm *mm, struct drm_printer *p)
-{
-	const struct drm_mm_node *entry;
-	u64 total_used = 0, total_free = 0, total = 0;
-
-	total_free += drm_mm_dump_hole(p, &mm->head_node);
-
-	drm_mm_for_each_node(entry, mm) {
-		drm_printf(p, "%#018llx-%#018llx: %llu: used\n", entry->start,
-			   entry->start + entry->size, entry->size);
-		total_used += entry->size;
-		total_free += drm_mm_dump_hole(p, entry);
-	}
-	total = total_free + total_used;
-
-	drm_printf(p, "total: %llu, used %llu free %llu\n", total,
-		   total_used, total_free);
-}
-EXPORT_SYMBOL(drm_mm_print);