Re: [PATCH v4 2/7] cxl/core: Remove CONFIG_CXL_SUSPEND and always build suspend.o

[Koralahalli Channabasappa, Smita]

On 6/9/2025 4:02 AM, Jonathan Cameron wrote:
On Tue, 3 Jun 2025 22:19:44 +0000
Smita Koralahalli <smita.koralahallichannabasa...@amd.com> wrote:

In preparation for soft-reserved resource handling, make the suspend
infrastructure always available by removing the CONFIG_CXL_SUSPEND
Kconfig option.

This ensures cxl_mem_active_inc()/dec() and cxl_mem_active() are
unconditionally available, enabling coordination between cxl_pci and
cxl_mem drivers during region setup and hotplug operations.

If these are no longer just being used for suspend, given there
is nothing else in the file, maybe move them to somewhere else?

There was recommendation to move the wait queue declaration and its
related changes to acpi.c. I was considering that. Let me know if there 
is any other best place for this.

Thanks
Smita



Co-developed-by: Nathan Fontenot <nathan.fonte...@amd.com>
Signed-off-by: Nathan Fontenot <nathan.fonte...@amd.com>
Co-developed-by: Terry Bowman <terry.bow...@amd.com>
Signed-off-by: Terry Bowman <terry.bow...@amd.com>
Signed-off-by: Smita Koralahalli <smita.koralahallichannabasa...@amd.com>
---
  drivers/cxl/Kconfig        | 4 ----
  drivers/cxl/core/Makefile  | 2 +-
  drivers/cxl/core/suspend.c | 5 ++++-
  drivers/cxl/cxlmem.h       | 9 ---------
  include/linux/pm.h         | 7 -------
  5 files changed, 5 insertions(+), 22 deletions(-)

diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
index cf1ba673b8c2..d09144c2002e 100644
--- a/drivers/cxl/Kconfig
+++ b/drivers/cxl/Kconfig
@@ -118,10 +118,6 @@ config CXL_PORT
        default CXL_BUS
        tristate
  
-config CXL_SUSPEND
-       def_bool y
-       depends on SUSPEND && CXL_MEM
-
  config CXL_REGION
        bool "CXL: Region Support"
        default CXL_BUS
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index 086df97a0fcf..035864db8a32 100644
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -1,6 +1,6 @@
  # SPDX-License-Identifier: GPL-2.0
  obj-$(CONFIG_CXL_BUS) += cxl_core.o
-obj-$(CONFIG_CXL_SUSPEND) += suspend.o
+obj-y += suspend.o
  
  ccflags-y += -I$(srctree)/drivers/cxl
  CFLAGS_trace.o = -DTRACE_INCLUDE_PATH=. -I$(src)
diff --git a/drivers/cxl/core/suspend.c b/drivers/cxl/core/suspend.c
index 29aa5cc5e565..5ba4b4de0e33 100644
--- a/drivers/cxl/core/suspend.c
+++ b/drivers/cxl/core/suspend.c
@@ -8,7 +8,10 @@ static atomic_t mem_active;
  
  bool cxl_mem_active(void)
  {
-       return atomic_read(&mem_active) != 0;
+       if (IS_ENABLED(CONFIG_CXL_MEM))
+               return atomic_read(&mem_active) != 0;
+
+       return false;
  }
  
  void cxl_mem_active_inc(void)
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 3ec6b906371b..1bd1e88c4cc0 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -853,17 +853,8 @@ int cxl_trigger_poison_list(struct cxl_memdev *cxlmd);
  int cxl_inject_poison(struct cxl_memdev *cxlmd, u64 dpa);
  int cxl_clear_poison(struct cxl_memdev *cxlmd, u64 dpa);
  
-#ifdef CONFIG_CXL_SUSPEND
  void cxl_mem_active_inc(void);
  void cxl_mem_active_dec(void);
-#else
-static inline void cxl_mem_active_inc(void)
-{
-}
-static inline void cxl_mem_active_dec(void)
-{
-}
-#endif
  
  int cxl_mem_sanitize(struct cxl_memdev *cxlmd, u16 cmd);
  
diff --git a/include/linux/pm.h b/include/linux/pm.h
index f0bd8fbae4f2..415928e0b6ca 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -35,14 +35,7 @@ static inline void pm_vt_switch_unregister(struct device 
*dev)
  }
  #endif /* CONFIG_VT_CONSOLE_SLEEP */
  
-#ifdef CONFIG_CXL_SUSPEND
  bool cxl_mem_active(void);
-#else
-static inline bool cxl_mem_active(void)
-{
-       return false;
-}
-#endif
  
  /*
   * Device power management