Michael, ping in case that you might forget this one forever as well.
On Mon, 2019-07-15 at 14:32 -0400, Qian Cai wrote: > At the beginning of setup_64.c, it has, > > #ifdef DEBUG > #define DBG(fmt...) udbg_printf(fmt) > #else > #define DBG(fmt...) > #endif > > where DBG() could be compiled away, and generate warnings, > > arch/powerpc/kernel/setup_64.c: In function 'initialize_cache_info': > arch/powerpc/kernel/setup_64.c:579:49: warning: suggest braces around > empty body in an 'if' statement [-Wempty-body] > DBG("Argh, can't find dcache properties !\n"); > ^ > arch/powerpc/kernel/setup_64.c:582:49: warning: suggest braces around > empty body in an 'if' statement [-Wempty-body] > DBG("Argh, can't find icache properties !\n"); > > Fix it by using the suggestions from Michael: > > "Neither of those sites should use DBG(), that's not really early boot > code, they should just use pr_warn(). > > And the other uses of DBG() in initialize_cache_info() should just be > removed. > > In smp_release_cpus() the entry/exit DBG's should just be removed, and > the spinning_secondaries line should just be pr_debug(). > > That would just leave the two calls in early_setup(). If we taught > udbg_printf() to return early when udbg_putc is NULL, then we could just > call udbg_printf() unconditionally and get rid of the DBG macro > entirely." > > Suggested-by: Michael Ellerman <m...@ellerman.id.au> > Signed-off-by: Qian Cai <c...@lca.pw> > --- > > v4: Use the suggestions from Michael and __func__ per checkpatch. > v3: Use no_printk() macro, and make sure that format and argument are always > verified by the compiler using a more generic form ##__VA_ARGS__ per Joe. > v2: Fix it by using a NOP while loop per Tyrel. > > arch/powerpc/kernel/setup_64.c | 26 ++++++-------------------- > arch/powerpc/kernel/udbg.c | 14 ++++++++------ > 2 files changed, 14 insertions(+), 26 deletions(-) > > diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c > index 44b4c432a273..d2af4c228970 100644 > --- a/arch/powerpc/kernel/setup_64.c > +++ b/arch/powerpc/kernel/setup_64.c > @@ -68,12 +68,6 @@ > > #include "setup.h" > > -#ifdef DEBUG > -#define DBG(fmt...) udbg_printf(fmt) > -#else > -#define DBG(fmt...) > -#endif > - > int spinning_secondaries; > u64 ppc64_pft_size; > > @@ -305,7 +299,7 @@ void __init early_setup(unsigned long dt_ptr) > /* Enable early debugging if any specified (see udbg.h) */ > udbg_early_init(); > > - DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr); > + udbg_printf(" -> %s(), dt_ptr: 0x%lx\n", __func__, dt_ptr); > > /* > * Do early initialization using the flattened device > @@ -362,11 +356,11 @@ void __init early_setup(unsigned long dt_ptr) > */ > this_cpu_enable_ftrace(); > > - DBG(" <- early_setup()\n"); > + udbg_printf(" <- %s()\n", __func__); > > #ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX > /* > - * This needs to be done *last* (after the above DBG() even) > + * This needs to be done *last* (after the above udbg_printf() even) > * > * Right after we return from this function, we turn on the MMU > * which means the real-mode access trick that btext does will > @@ -436,8 +430,6 @@ void smp_release_cpus(void) > if (!use_spinloop()) > return; > > - DBG(" -> smp_release_cpus()\n"); > - > /* All secondary cpus are spinning on a common spinloop, release them > * all now so they can start to spin on their individual paca > * spinloops. For non SMP kernels, the secondary cpus never get out > @@ -456,9 +448,7 @@ void smp_release_cpus(void) > break; > udelay(1); > } > - DBG("spinning_secondaries = %d\n", spinning_secondaries); > - > - DBG(" <- smp_release_cpus()\n"); > + pr_debug("spinning_secondaries = %d\n", spinning_secondaries); > } > #endif /* CONFIG_SMP || CONFIG_KEXEC_CORE */ > > @@ -551,8 +541,6 @@ void __init initialize_cache_info(void) > struct device_node *cpu = NULL, *l2, *l3 = NULL; > u32 pvr; > > - DBG(" -> initialize_cache_info()\n"); > - > /* > * All shipping POWER8 machines have a firmware bug that > * puts incorrect information in the device-tree. This will > @@ -576,10 +564,10 @@ void __init initialize_cache_info(void) > */ > if (cpu) { > if (!parse_cache_info(cpu, false, &ppc64_caches.l1d)) > - DBG("Argh, can't find dcache properties !\n"); > + pr_warn("Argh, can't find dcache properties !\n"); > > if (!parse_cache_info(cpu, true, &ppc64_caches.l1i)) > - DBG("Argh, can't find icache properties !\n"); > + pr_warn("Argh, can't find icache properties !\n"); > > /* > * Try to find the L2 and L3 if any. Assume they are > @@ -604,8 +592,6 @@ void __init initialize_cache_info(void) > > cur_cpu_spec->dcache_bsize = dcache_bsize; > cur_cpu_spec->icache_bsize = icache_bsize; > - > - DBG(" <- initialize_cache_info()\n"); > } > > /* > diff --git a/arch/powerpc/kernel/udbg.c b/arch/powerpc/kernel/udbg.c > index a384e7c8b01c..01595e8cafe7 100644 > --- a/arch/powerpc/kernel/udbg.c > +++ b/arch/powerpc/kernel/udbg.c > @@ -120,13 +120,15 @@ int udbg_write(const char *s, int n) > #define UDBG_BUFSIZE 256 > void udbg_printf(const char *fmt, ...) > { > - char buf[UDBG_BUFSIZE]; > - va_list args; > + if (udbg_putc) { > + char buf[UDBG_BUFSIZE]; > + va_list args; > > - va_start(args, fmt); > - vsnprintf(buf, UDBG_BUFSIZE, fmt, args); > - udbg_puts(buf); > - va_end(args); > + va_start(args, fmt); > + vsnprintf(buf, UDBG_BUFSIZE, fmt, args); > + udbg_puts(buf); > + va_end(args); > + } > } > > void __init udbg_progress(char *s, unsigned short hex)