Hi Arnd, On 11/18/2021 8:54 PM, Arnd Bergmann wrote:
On Mon, Nov 15, 2021 at 12:33 PM Sai Prakash Ranjan <quic_saipraka@xxxxxxxxxxx> wrote:/* * Generic IO read/write. These perform native-endian accesses. */ -#define __raw_writeb __raw_writeb -static inline void __raw_writeb(u8 val, volatile void __iomem *addr) +static inline void arch_raw_writeb(u8 val, volatile void __iomem *addr) { asm volatile("strb %w0, [%1]" : : "rZ" (val), "r" (addr)); }Woundn't removing the #define here will break the logic in include/asm-generic/io.h, making it fall back to the pointer-dereference version for the actual access?
#defines for these are added in mmio-instrumented.h header which is included in arm64/asm/io.h, so it won't break the logic by falling back to pointer-dereference.
+#if IS_ENABLED(CONFIG_TRACE_MMIO_ACCESS) && !(defined(__DISABLE_TRACE_MMIO__)) +DECLARE_TRACEPOINT(rwmmio_write); +DECLARE_TRACEPOINT(rwmmio_read); + +void log_write_mmio(const char *width, volatile void __iomem *addr); +void log_read_mmio(const char *width, const volatile void __iomem *addr); + +#define __raw_write(v, a, _l) ({ \ + volatile void __iomem *_a = (a); \ + if (tracepoint_enabled(rwmmio_write)) \ + log_write_mmio(__stringify(write##_l), _a); \ + arch_raw_write##_l((v), _a); \ + })This feels like it's getting too big to be inlined. Have you considered integrating this with the lib/logic_iomem.c infrastructure instead? That already provides a way to override MMIO areas, and it lets you do the logging from a single place rather than having it duplicated in every single caller. It also provides a way of filtering it based on the ioremap() call.
Thanks for the suggestion, will look at the logic_iomem.c and see if it fits our
usecase. Thanks, Sai
