[PATCH v2 4/8] clk: tegra: bpmp: Convert to printbuf

Kent Overstreet
2022-04-21T23:50:41Z

This converts from seq_buf to printbuf, which is similar but heap
allocates the string buffer.

Previously in this code the string buffer was allocated on the stack;
this means we've added a new potential memory allocation failure. This
is fine though since it's only for a dev_printk() message.

Memory allocation context: printbuf doesn't take gfp flags, instead we
prefer the new memalloc_no*_(save|restore) interfaces to be used. Here
the surrounding code is already allocating with GFP_KERNEL, so
everything is fine.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
---
drivers/clk/tegra/clk-bpmp.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/tegra/clk-bpmp.c b/drivers/clk/tegra/clk-bpmp.c
index 6ecf18f71c..77a8c47806 100644
--- a/drivers/clk/tegra/clk-bpmp.c
+++ b/drivers/clk/tegra/clk-bpmp.c
@@ -5,7 +5,7 @@

#include <linux/clk-provider.h>
#include <linux/device.h>
-#include <linux/seq_buf.h>
+#include <linux/printbuf.h>
#include <linux/slab.h>

#include <soc/tegra/bpmp.h>
@@ -360,39 +360,38 @@ static void tegra_bpmp_clk_info_dump(struct tegra_bpmp *bpmp,
const struct tegra_bpmp_clk_info *info)
{
const char *prefix = "";
- struct seq_buf buf;
+ struct printbuf buf = PRINTBUF;
unsigned int i;
- char flags[64];
-
- seq_buf_init(&buf, flags, sizeof(flags));

if (info->flags)
- seq_buf_printf(&buf, "(");
+ pr_buf(&buf, "(");

if (info->flags & TEGRA_BPMP_CLK_HAS_MUX) {
- seq_buf_printf(&buf, "%smux", prefix);
+ pr_buf(&buf, "%smux", prefix);
prefix = ", ";
}

if ((info->flags & TEGRA_BPMP_CLK_HAS_SET_RATE) == 0) {
- seq_buf_printf(&buf, "%sfixed", prefix);
+ pr_buf(&buf, "%sfixed", prefix);
prefix = ", ";
}

if (info->flags & TEGRA_BPMP_CLK_IS_ROOT) {
- seq_buf_printf(&buf, "%sroot", prefix);
+ pr_buf(&buf, "%sroot", prefix);
prefix = ", ";
}

if (info->flags)
- seq_buf_printf(&buf, ")");
+ pr_buf(&buf, ")");

dev_printk(level, bpmp->dev, "%03u: %s\n", info->id, info->name);
- dev_printk(level, bpmp->dev, " flags: %lx %s\n", info->flags, flags);
+ dev_printk(level, bpmp->dev, " flags: %lx %s\n", info->flags, printbuf_str(&buf));
dev_printk(level, bpmp->dev, " parents: %u\n", info->num_parents);

for (i = 0; i < info->num_parents; i++)
dev_printk(level, bpmp->dev, " %03u\n", info->parents[i]);
+
+ printbuf_exit(&buf);
}

static int tegra_bpmp_probe_clocks(struct tegra_bpmp *bpmp,
--
2.35.2