feat(util/printk): new more readable and robust printk implemenation

A from-sratch improved implementation of printk that allows printing strings larger than the allocated print buffer. It also makes this buffer statically allocated instead of allocating it on the printing cpu stack. Finally, it removes the per-uart implementation uart_puts function as this is essnetially replicated behavior, only the uart_putc is needed. This logic is now part of the console itself. The format printf attribute is also added so that errors in the format string type identifiers are detected at compile time. Signed-off-by: Jose Martins <josemartins90@gmail.com>
bao-project · Oct 13, 2023 · 93edbbb · 93edbbb
1 parent dafd38b
commit 93edbbb
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Showing 19 changed files with 221 additions and 216 deletions.
diff --git a/src/arch/armv8/aarch32/aborts.c b/src/arch/armv8/aarch32/aborts.c
@@ -10,10 +10,10 @@
 void internal_abort_handler(unsigned long gprs[]) {
 
     for(ssize_t i = 14; i >= 0; i--) {
-        printk("x%d:\t\t0x%0lx\n", i, gprs[14 - i]);
+        console_printk("x%d:\t\t0x%0lx\n", i, gprs[14 - i]);
     }
-    printk("ESR:\t0x%0lx\n", sysreg_esr_el2_read());
-    printk("ELR:\t0x%0lx\n", sysreg_elr_el2_read());
-    printk("FAR:\t0x%0lx\n", sysreg_far_el2_read());
+    console_printk("ESR:\t0x%0lx\n", sysreg_esr_el2_read());
+    console_printk("ELR:\t0x%0lx\n", sysreg_elr_el2_read());
+    console_printk("FAR:\t0x%0lx\n", sysreg_far_el2_read());
     ERROR("cpu%d internal hypervisor abort - PANIC\n", cpu()->id);
 }
diff --git a/src/arch/armv8/aarch64/aborts.c b/src/arch/armv8/aarch64/aborts.c
@@ -10,11 +10,11 @@
 void internal_abort_handler(unsigned long gprs[]) {
 
     for(size_t i = 0; i < 31; i++) {
-        printk("x%d:\t\t0x%0lx\n", i, gprs[i]);
+        console_printk("x%d:\t\t0x%0lx\n", i, gprs[i]);
     }
-    printk("SP:\t\t0x%0lx\n", gprs[31]);
-    printk("ESR:\t0x%0lx\n", sysreg_esr_el2_read());
-    printk("ELR:\t0x%0lx\n", sysreg_elr_el2_read());
-    printk("FAR:\t0x%0lx\n", sysreg_far_el2_read());
+    console_printk("SP:\t\t0x%0lx\n", gprs[31]);
+    console_printk("ESR:\t0x%0lx\n", sysreg_esr_el2_read());
+    console_printk("ELR:\t0x%0lx\n", sysreg_elr_el2_read());
+    console_printk("FAR:\t0x%0lx\n", sysreg_far_el2_read());
     ERROR("cpu%d internal hypervisor abort - PANIC\n", cpu()->id);
 }
diff --git a/src/arch/riscv/sync_exceptions.c b/src/arch/riscv/sync_exceptions.c
@@ -13,11 +13,11 @@
 void internal_exception_handler(unsigned long gprs[]) {
 
     for(int i = 0; i < 31; i++) {
-        printk("x%d:\t\t0x%0lx\n", i, gprs[i]);
+        console_printk("x%d:\t\t0x%0lx\n", i, gprs[i]);
     }
-    printk("sstatus:\t0x%0lx\n", CSRR(sstatus));
-    printk("stval:\t\t0x%0lx\n", CSRR(stval));
-    printk("sepc:\t\t0x%0lx\n", CSRR(sepc));
+    console_printk("sstatus:\t0x%0lx\n", CSRR(sstatus));
+    console_printk("stval:\t\t0x%0lx\n", CSRR(stval));
+    console_printk("sepc:\t\t0x%0lx\n", CSRR(sepc));
     ERROR("cpu%d internal hypervisor abort - PANIC\n", cpu()->id);
 }
 

diff --git a/src/core/console.c b/src/core/console.c
@@ -11,10 +11,12 @@
 #include <mem.h>
 #include <fences.h>
 #include <spinlock.h>
+#include <printk.h>
+#include <util.h>
 
-volatile bao_uart_t *uart;
-bool ready = false;
-static spinlock_t print_lock = SPINLOCK_INITVAL;
+static volatile bao_uart_t *uart;
+static bool console_ready = false;
+static spinlock_t console_lock = SPINLOCK_INITVAL;
 
 void console_init()
 {
@@ -31,16 +33,40 @@ void console_init()
         uart_init(uart);
         uart_enable(uart);
 
-        ready = true;
+        console_ready = true;
     }
 
     cpu_sync_and_clear_msgs(&cpu_glb_sync);
 }
 
-void console_write(char const* const str)
+
+void console_write(const char* buf, size_t n)
 {
-    if (!ready) return;
-    spin_lock(&print_lock);
-    uart_puts(uart, str);
-    spin_unlock(&print_lock);
+    while (!console_ready);
+    for (size_t i = 0; i < n; i++) {
+        if (buf[i] == '\n') {
+            uart_putc(uart, '\r');
+        }
+        uart_putc(uart, buf[i]);
+    }
+}
+
+#define PRINTF_BUFFER_LEN   (256)
+static char console_bufffer[PRINTF_BUFFER_LEN];
+
+__attribute__((format(printf, 1, 2))) void console_printk(const char* fmt, ...)
+{
+    va_list args;
+    size_t chars_writen;
+    const char* fmt_it = fmt;
+
+    va_start(args, fmt);
+    spin_lock(&console_lock);
+    while (*fmt_it != '\0') {
+        chars_writen =
+            vsnprintk(console_bufffer, PRINTF_BUFFER_LEN, &fmt_it, &args);
+        console_write(console_bufffer, min(PRINTF_BUFFER_LEN, chars_writen));
+    }
+    spin_unlock(&console_lock);
+    va_end(args);
 }
diff --git a/src/core/inc/bao.h b/src/core/inc/bao.h
@@ -11,20 +11,20 @@
 #ifndef __ASSEMBLER__
 
 #include <types.h>
-#include <printk.h>
+#include <console.h>
 #include <util.h>
 
 #define INFO(args, ...) \
-    printk("BAO INFO: " args "\n" __VA_OPT__(, ) __VA_ARGS__);
+    console_printk("BAO INFO: " args "\n" __VA_OPT__(, ) __VA_ARGS__);
 
 #define WARNING(args, ...) \
-    printk("BAO WARNING: " args "\n" __VA_OPT__(, ) __VA_ARGS__);
+    console_printk("BAO WARNING: " args "\n" __VA_OPT__(, ) __VA_ARGS__);
 
-#define ERROR(args, ...)                                            \
-    {                                                               \
-        printk("BAO ERROR: " args "\n" __VA_OPT__(, ) __VA_ARGS__); \
-        while (1)                                                   \
-            ;                                                       \
+#define ERROR(args, ...)                                                    \
+    {                                                                       \
+        console_printk("BAO ERROR: " args "\n" __VA_OPT__(, ) __VA_ARGS__); \
+        while (1)                                                           \
+            ;                                                               \
     }
 
 #endif /* __ASSEMBLER__ */

diff --git a/src/core/inc/console.h b/src/core/inc/console.h
@@ -9,6 +9,7 @@
 #include <bao.h>
 
 void console_init();
-void console_write(char const* const str);
+void console_write(const char* buf, size_t n);
+void console_printk(const char* fmt, ...);
 
 #endif /* __CONSOLE_H__ */
diff --git a/src/core/init.c b/src/core/init.c
@@ -27,7 +27,7 @@ void init(cpuid_t cpu_id, paddr_t load_addr)
     console_init();
 
     if (cpu()->id == CPU_MASTER) {
-        printk("Bao Hypervisor\n\r");
+        console_printk("Bao Hypervisor\n\r");
     }
 
     interrupts_init();

diff --git a/src/lib/inc/printk.h b/src/lib/inc/printk.h
@@ -7,7 +7,9 @@
 #define __PRINTK_H
 
 #include <bao.h>
+#include <stdarg.h>
 
-size_t printk(const char *fmt, ...);
+size_t vsnprintk(char* buf, size_t buf_size, const char** fmt,
+    va_list* args);
 
 #endif /* __PRINTK_H */