On 05/23/2018 05:17 PM, Marcin Dziegielewski wrote:
In some cases, users can want set write buffer size manually, e.g. to
adjust it to specific workload. This patch provides the possibility to set
write buffer size via module parameter feature.
Signed-off-by: Marcin Dziegielewski <marcin.dziegielewski@xxxxxxxxx>
Signed-off-by: Igor Konopko <igor.j.konopko@xxxxxxxxx>
---
drivers/lightnvm/pblk-init.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
index d65d2f9..9a7213e 100644
--- a/drivers/lightnvm/pblk-init.c
+++ b/drivers/lightnvm/pblk-init.c
@@ -20,6 +20,11 @@
#include "pblk.h"
+unsigned int write_buffer_size;
+
+module_param(write_buffer_size, uint, 0644);
+MODULE_PARM_DESC(write_buffer_size, "number of entries in a write buffer");
+
static struct kmem_cache *pblk_ws_cache, *pblk_rec_cache, *pblk_g_rq_cache,
*pblk_w_rq_cache;
static DECLARE_RWSEM(pblk_lock);
@@ -172,10 +177,15 @@ static int pblk_rwb_init(struct pblk *pblk)
struct nvm_tgt_dev *dev = pblk->dev;
struct nvm_geo *geo = &dev->geo;
struct pblk_rb_entry *entries;
- unsigned long nr_entries;
+ unsigned long nr_entries, buffer_size;
unsigned int power_size, power_seg_sz;
- nr_entries = pblk_rb_calculate_size(pblk->pgs_in_buffer);
+ if (write_buffer_size)
+ buffer_size = write_buffer_size;
+ else
+ buffer_size = pblk->pgs_in_buffer;
+
+ nr_entries = pblk_rb_calculate_size(buffer_size);
Would it make sense to include a check to make sure that buffer size
does not become less than pblk->pgs_in_buffer?
entries = vzalloc(nr_entries * sizeof(struct pblk_rb_entry));
if (!entries)
