This is a note to let you know that I've just added the patch titled
scsi: hisi_sas: Allocate DFX memory during dump trigger
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-hisi_sas-allocate-dfx-memory-during-dump-trigge.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 79e22c0c4b2a961b8942f2f788cbf3c7dda7017d
Author: Yihang Li <liyihang9@xxxxxxxxxx>
Date: Wed Sep 13 10:15:27 2023 +0800
scsi: hisi_sas: Allocate DFX memory during dump trigger
[ Upstream commit 63f0733d07ce60252e885602b39571ade0441015 ]
Currently, if CONFIG_SCSI_HISI_SAS_DEBUGFS_DEFAULT_ENABLE is enabled, the
memory space used by DFX is allocated during device initialization, which
occupies a large number of memory resources. The memory usage before and
after the driver is loaded is as follows:
Memory usage before the driver is loaded:
$ free -m
total used free shared buff/cache available
Mem: 867352 2578 864037 11 735 861681
Swap: 4095 0 4095
Memory usage after the driver which include 4 HBAs is loaded:
$ insmod hisi_sas_v3_hw.ko
$ free -m
total used free shared buff/cache available
Mem: 867352 4760 861848 11 743 859495
Swap: 4095 0 4095
The driver with 4 HBAs connected will allocate about 110 MB of memory
without enabling debugfs.
Therefore, to avoid wasting memory resources, DFX memory is allocated
during dump triggering. The dump may fail due to memory allocation
failure. After this change, each dump costs about 10 MB of memory, and each
dump lasts about 100 ms.
Signed-off-by: Yihang Li <liyihang9@xxxxxxxxxx>
Signed-off-by: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1694571327-78697-4-git-send-email-chenxiang66@xxxxxxxxxxxxx
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Stable-dep-of: 9f564f15f884 ("scsi: hisi_sas: Create all dump files during debugfs initialization")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index 3d511c44c02d..1e4550156b73 100644
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -343,7 +343,7 @@ struct hisi_sas_hw {
u8 reg_index, u8 reg_count, u8 *write_data);
void (*wait_cmds_complete_timeout)(struct hisi_hba *hisi_hba,
int delay_ms, int timeout_ms);
- void (*debugfs_snapshot_regs)(struct hisi_hba *hisi_hba);
+ int (*debugfs_snapshot_regs)(struct hisi_hba *hisi_hba);
int complete_hdr_size;
const struct scsi_host_template *sht;
};
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
index 10f048b5a489..cea548655629 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -558,7 +558,7 @@ static int experimental_iopoll_q_cnt;
module_param(experimental_iopoll_q_cnt, int, 0444);
MODULE_PARM_DESC(experimental_iopoll_q_cnt, "number of queues to be used as poll mode, def=0");
-static void debugfs_snapshot_regs_v3_hw(struct hisi_hba *hisi_hba);
+static int debugfs_snapshot_regs_v3_hw(struct hisi_hba *hisi_hba);
static u32 hisi_sas_read32(struct hisi_hba *hisi_hba, u32 off)
{
@@ -3867,37 +3867,6 @@ static void debugfs_create_files_v3_hw(struct hisi_hba *hisi_hba)
&debugfs_ras_v3_hw_fops);
}
-static void debugfs_snapshot_regs_v3_hw(struct hisi_hba *hisi_hba)
-{
- int debugfs_dump_index = hisi_hba->debugfs_dump_index;
- struct device *dev = hisi_hba->dev;
- u64 timestamp = local_clock();
-
- if (debugfs_dump_index >= hisi_sas_debugfs_dump_count) {
- dev_warn(dev, "dump count exceeded!\n");
- return;
- }
-
- do_div(timestamp, NSEC_PER_MSEC);
- hisi_hba->debugfs_timestamp[debugfs_dump_index] = timestamp;
-
- debugfs_snapshot_prepare_v3_hw(hisi_hba);
-
- debugfs_snapshot_global_reg_v3_hw(hisi_hba);
- debugfs_snapshot_port_reg_v3_hw(hisi_hba);
- debugfs_snapshot_axi_reg_v3_hw(hisi_hba);
- debugfs_snapshot_ras_reg_v3_hw(hisi_hba);
- debugfs_snapshot_cq_reg_v3_hw(hisi_hba);
- debugfs_snapshot_dq_reg_v3_hw(hisi_hba);
- debugfs_snapshot_itct_reg_v3_hw(hisi_hba);
- debugfs_snapshot_iost_reg_v3_hw(hisi_hba);
-
- debugfs_create_files_v3_hw(hisi_hba);
-
- debugfs_snapshot_restore_v3_hw(hisi_hba);
- hisi_hba->debugfs_dump_index++;
-}
-
static ssize_t debugfs_trigger_dump_v3_hw_write(struct file *file,
const char __user *user_buf,
size_t count, loff_t *ppos)
@@ -3905,9 +3874,6 @@ static ssize_t debugfs_trigger_dump_v3_hw_write(struct file *file,
struct hisi_hba *hisi_hba = file->f_inode->i_private;
char buf[8];
- if (hisi_hba->debugfs_dump_index >= hisi_sas_debugfs_dump_count)
- return -EFAULT;
-
if (count > 8)
return -EFAULT;
@@ -3918,7 +3884,10 @@ static ssize_t debugfs_trigger_dump_v3_hw_write(struct file *file,
return -EFAULT;
down(&hisi_hba->sem);
- debugfs_snapshot_regs_v3_hw(hisi_hba);
+ if (debugfs_snapshot_regs_v3_hw(hisi_hba)) {
+ up(&hisi_hba->sem);
+ return -EFAULT;
+ }
up(&hisi_hba->sem);
return count;
@@ -4704,7 +4673,7 @@ static int debugfs_alloc_v3_hw(struct hisi_hba *hisi_hba, int dump_index)
{
const struct hisi_sas_hw *hw = hisi_hba->hw;
struct device *dev = hisi_hba->dev;
- int p, c, d, r, i;
+ int p, c, d, r;
size_t sz;
for (r = 0; r < DEBUGFS_REGS_NUM; r++) {
@@ -4784,11 +4753,48 @@ static int debugfs_alloc_v3_hw(struct hisi_hba *hisi_hba, int dump_index)
return 0;
fail:
- for (i = 0; i < hisi_sas_debugfs_dump_count; i++)
- debugfs_release_v3_hw(hisi_hba, i);
+ debugfs_release_v3_hw(hisi_hba, dump_index);
return -ENOMEM;
}
+static int debugfs_snapshot_regs_v3_hw(struct hisi_hba *hisi_hba)
+{
+ int debugfs_dump_index = hisi_hba->debugfs_dump_index;
+ struct device *dev = hisi_hba->dev;
+ u64 timestamp = local_clock();
+
+ if (debugfs_dump_index >= hisi_sas_debugfs_dump_count) {
+ dev_warn(dev, "dump count exceeded!\n");
+ return -EINVAL;
+ }
+
+ if (debugfs_alloc_v3_hw(hisi_hba, debugfs_dump_index)) {
+ dev_warn(dev, "failed to alloc memory\n");
+ return -ENOMEM;
+ }
+
+ do_div(timestamp, NSEC_PER_MSEC);
+ hisi_hba->debugfs_timestamp[debugfs_dump_index] = timestamp;
+
+ debugfs_snapshot_prepare_v3_hw(hisi_hba);
+
+ debugfs_snapshot_global_reg_v3_hw(hisi_hba);
+ debugfs_snapshot_port_reg_v3_hw(hisi_hba);
+ debugfs_snapshot_axi_reg_v3_hw(hisi_hba);
+ debugfs_snapshot_ras_reg_v3_hw(hisi_hba);
+ debugfs_snapshot_cq_reg_v3_hw(hisi_hba);
+ debugfs_snapshot_dq_reg_v3_hw(hisi_hba);
+ debugfs_snapshot_itct_reg_v3_hw(hisi_hba);
+ debugfs_snapshot_iost_reg_v3_hw(hisi_hba);
+
+ debugfs_create_files_v3_hw(hisi_hba);
+
+ debugfs_snapshot_restore_v3_hw(hisi_hba);
+ hisi_hba->debugfs_dump_index++;
+
+ return 0;
+}
+
static void debugfs_phy_down_cnt_init_v3_hw(struct hisi_hba *hisi_hba)
{
struct dentry *dir = debugfs_create_dir("phy_down_cnt",
@@ -4875,7 +4881,6 @@ static void debugfs_exit_v3_hw(struct hisi_hba *hisi_hba)
static void debugfs_init_v3_hw(struct hisi_hba *hisi_hba)
{
struct device *dev = hisi_hba->dev;
- int i;
hisi_hba->debugfs_dir = debugfs_create_dir(dev_name(dev),
hisi_sas_debugfs_dir);
@@ -4892,14 +4897,6 @@ static void debugfs_init_v3_hw(struct hisi_hba *hisi_hba)
debugfs_phy_down_cnt_init_v3_hw(hisi_hba);
debugfs_fifo_init_v3_hw(hisi_hba);
-
- for (i = 0; i < hisi_sas_debugfs_dump_count; i++) {
- if (debugfs_alloc_v3_hw(hisi_hba, i)) {
- debugfs_exit_v3_hw(hisi_hba);
- dev_dbg(dev, "failed to init debugfs!\n");
- break;
- }
- }
}
static int
