[PATCH v2 07/16] dmaengine: idxd: create kmem cache for event log fault items

From: Fenghua Yu
Date: Mon Mar 06 2023 - 11:46:01 EST


From: Dave Jiang <dave.jiang@xxxxxxxxx>

Add a kmem cache per device for allocating event log fault context. The
context allows an event log entry to be copied and passed to a software
workqueue to be processed. Due to each device can have different sized
event log entry depending on device type, it's not possible to have a
global kmem cache.

Tested-by: Tony Zhu <tony.zhu@xxxxxxxxx>
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Co-developed-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
---
drivers/dma/idxd/idxd.h | 10 ++++++++++
drivers/dma/idxd/init.c | 9 +++++++++
drivers/dma/idxd/sysfs.c | 1 +
3 files changed, 20 insertions(+)

diff --git a/drivers/dma/idxd/idxd.h b/drivers/dma/idxd/idxd.h
index 6e56361ae658..c5d99c179902 100644
--- a/drivers/dma/idxd/idxd.h
+++ b/drivers/dma/idxd/idxd.h
@@ -274,6 +274,15 @@ struct idxd_evl {
u16 head;
};

+struct idxd_evl_fault {
+ struct work_struct work;
+ struct idxd_wq *wq;
+ u8 status;
+
+ /* make this last member always */
+ struct __evl_entry entry[];
+};
+
struct idxd_device {
struct idxd_dev idxd_dev;
struct idxd_driver_data *data;
@@ -331,6 +340,7 @@ struct idxd_device {

unsigned long *opcap_bmap;
struct idxd_evl *evl;
+ struct kmem_cache *evl_cache;

struct dentry *dbgfs_dir;
struct dentry *dbgfs_evl_file;
diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
index d19bc6389221..a7c98fac7a85 100644
--- a/drivers/dma/idxd/init.c
+++ b/drivers/dma/idxd/init.c
@@ -346,6 +346,15 @@ static int idxd_init_evl(struct idxd_device *idxd)

spin_lock_init(&evl->lock);
evl->size = IDXD_EVL_SIZE_MIN;
+
+ idxd->evl_cache = kmem_cache_create(dev_name(idxd_confdev(idxd)),
+ sizeof(struct idxd_evl_fault) + evl_ent_size(idxd),
+ 0, 0, NULL);
+ if (!idxd->evl_cache) {
+ kfree(evl);
+ return -ENOMEM;
+ }
+
idxd->evl = evl;
return 0;
}
diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
index 163fdfaa5022..8b9dfa0d2b99 100644
--- a/drivers/dma/idxd/sysfs.c
+++ b/drivers/dma/idxd/sysfs.c
@@ -1718,6 +1718,7 @@ static void idxd_conf_device_release(struct device *dev)
kfree(idxd->wqs);
kfree(idxd->engines);
kfree(idxd->evl);
+ kmem_cache_destroy(idxd->evl_cache);
ida_free(&idxd_ida, idxd->id);
bitmap_free(idxd->opcap_bmap);
kfree(idxd);
--
2.37.1